WO2013013098A1

WO2013013098A1 - System and method for creation of cox maze lesions

Info

Publication number: WO2013013098A1
Application number: PCT/US2012/047484
Authority: WO
Inventors: James L. Cox; Jay J. Eum
Original assignee: Adagio Medical, Inc.
Priority date: 2011-07-19
Filing date: 2012-07-19
Publication date: 2013-01-24

Abstract

A catheter system and a method for creating Cox maze lesions in the heart.

Description

SYSTEM AND METHOD FOR CREATION OF COX MAZE LESIONS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims the benefit of priority to U.S. Provisional Patent Application No. 61/572,611, filed July 19, 2011, and U.S. Provisional Patent Application No. 61/510,007, filed July 20, 2011, the entire disclosures of which are hereby incorporated herein by reference in their entirety.

FIELD

[0002] The present disclosure relates generally to medical devices, systems and methods for treating atrial fibrillation by creating transmural lesions in the heart.

BACKGROUND

Introduction

[0003] Atrial fibrillation is a heart condition in which the left or right atrium of the heart does not beat properly. It is often caused by aberrant electrical behavior of some portion of the atrial wall. Certain parts of the atria, or nearby structures such as the pulmonary veins, can misfire in their production or conduction of the electrical signals that control contraction of the heart, creating abnormal electrical signals that prompt the atria to contract between normal contractions caused by the normal cascade of electrical impulses. This can be caused by spots of ischemic tissue, referred to as ectopic foci, or by electrically active fibers in the pulmonary veins, for example. Currently, the Cox Maze procedure, developed by Dr. James Cox in the 1980's, is the surest method of eliminating atrial fibrillation. In the Cox Maze procedure, the atrial wall is cut with a scalpel in particular patterns which isolate the foci of arrhythmia from the rest of the atrial wall, and then sewn back together. Upon healing, the resultant scar tissue serves to interrupt ectopic re-entry pathways and other aberrant electrical conduction and prevent arrhythmia and fibrillation. There are several variations of the Cox maze procedure, each involving variations in the number and placement of lesions created.

[0004] The original Cox maze procedure was an open chest procedure requiring surgically opening the atrium after opening the chest. The procedure itself has a high success rate, though due to the open chest/open heart nature of the procedure, and the requirement to stop the heart and establish a coronary bypass, it is reserved for severe cases of atrial fibrillation. [0005] The Cox maze procedure has been performed using ablation catheters in both transthoracic epicardial approaches and transvascular endocardial approaches. In transthoracic epicardial approaches, catheters or small probes are used to create linear lesions in the heart wall along lines corresponding to the maze of the Cox maze procedure. In the transvascular endocardial approaches, a catheter is navigated through the vasculature of the patient to the atrium, pressed against the inner wall of the atrium, and energized to create lesions corresponding to the maze of the Cox maze procedure. In either approach, various ablation catheters have been proposed for creation of the lesion, including flexible cryoprobes or cryocatheters, bipolar RF catheters, monopolar RF catheters (using ground patches on the patient's skin), microwave catheters, laser catheters, and ultrasound catheters. These approaches are attractive because they are minimally invasive and can be performed on a beating heart. However, these approaches have a low success rate. We theorize that the low success rate may be due to incomplete lesion formation. A fully transmural lesion is required to ensure that the electrical impulse causing atrial fibrillation are completely isolated from the remainder of the atrium, and this is difficult to achieve with beating heart procedures.

[0006] A major challenge to the effective epicardial application of ablative energy sources to cardiac tissue without the use of the heart-lung machine ("off-pump") is that during normal heart function the atria are filled with blood at 37 °C that is moving through the atria at roughly 5 liters per minute. If cryothermia energy is applied epicardially, this atrial blood flow acts as a "cooling sink," warming the heart wall and making it difficult to lower the endocardial surface of the atrial wall to a lethal temperature (roughly -30°C). Thus, lesion transmurality is extremely difficult to attain. Similarly, if heat-based energy sources such as RF, microwave, laser, or HIFU are applied to the epicardial surface without using the heart-lung machine to empty the atria, the blood flowing through the atrium acts as a heat sink, cooling the heart wall making it difficult to raise the endocardial surface of the atrial wall to a lethal temperature (roughly 55°C). These problems can theoretically be overcome by using a clamp in which both tines of the clamps are capable of delivering ablative energy such as RF or cryothermia. However, this approach requires that one of the tines of the camp be placed inside the atrium and cannot be used to create all of the Cox maze lesions without using the heart-lung machine. SUMMARY

[0007] The devices and methods described below provide for minimally invasive accomplishment of the Cox maze procedure. The method is accomplished with a catheter system including two catheters. An endocardial catheter is navigated through the patient's aorta or vena cava to the inside of the heart, while an epicardial catheter is inserted into the chest and navigated to a position outside the heart. The distal segments are roughly aligned on opposite sides of the heart wall, and along the line of a desired lesion, and then secured to each other, across the heart wall, with magnets fixed to each distal segment. After the position of the catheters along the line of the desired lesion is confirmed, one of the catheters is operated to ablate the heart wall along the line of the desired lesion to create a lesion of the Cox maze. The two catheters are repositioned and operated to create all the lesions of the Cox Maze procedure. In this method, the Cox maze lesions may be created to cure atrial fibrillation on a beating heart, without placing the patient on bypass, stopping the heart, or opening the patient's chest.

[0008] After creation of each lesion, the catheter system may be used to check the lesion and ensure that it extends completely across the wall of the atrium and encompasses the endocardial wall of the atrium. Because the endocardial catheter is held securely in place along the lesion line during the procedure, electrodes on the endocardial catheter can be used to check the impedance of the heart wall and apply pacing pulses to the heart wall, along the line of the lesion, and thereby ascertain whether the lesion is complete or incomplete before magnetically releasing the epicardial catheter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 shows a cross-sectional view of the human heart depicting the location of a few of the lesions created in the vicinity of the pulmonary veins in a Cox Maze procedure.

[0010] Figure 2 shows a cross-sectional view of the human heart depicting the placement of the endocardial catheter for the production of the Superior Left Atrial Lesion.

[0011] Figure 3 shows a view of the epicardial surface of the human heart depicting the placement of the epicardial catheter for the production of the Superior Left Atrial Lesion.

[0012] Figures 4, 5 and 6 illustrate the apposition of the epicardial catheter and endocardial catheter and the process of aligning the catheters. [0013] Figure 7 illustrates the use of electrodes on the endocardial catheter to test the atrial wall to determine if a lesion created by the system is completely transmural, suitably contiguous and in the correct position.

[0014] Figure 8 shows schematic views of the human heart depicting the effect of the Maze VII lesion pattern on macro re-entrant circuits.

[0015] Figure 9 is a schematic diagram of a view of the human heart showing the SVC-IVC Maze VII lesion, which extends between the superior vena cava (SVC) and inferior vena cava (IVC).

[0016] Figure 10 is a schematic diagram of a view of the human heart showing the location of the "T" lesion in relation to the SVC-IVC lesion.

[0017] Figure 11 is a schematic diagram of a view of the human heart showing the location of the RA lateral lesion in relation to the SVC-IVC and T lesions.

[0018] Figure 12 is a schematic diagram of a view of the human heart showing the location of the Coronary Sinus lesion in relation to the SVC-IVC lesion, the T lesion and the RA lateral lesion.

[0019] Figure 13 is a schematic diagram is a schematic diagram of a view of the human heart showing the location of the Inferior LA lesion in relation to the Coronary Sinus, SVC-IVC, T and the RA lateral lesions.

[0020] Figure 14 is a schematic diagram of a view of the human heart showing the location of the Superior LA lesion in relation to the Inferior LA, Coronary Sinus, SVC-IVC, T and RA lateral lesions.

[0021] Figure 15 is a schematic diagram of a view of the human heart showing the location of the right PV lesion across the ostia of the right pulmonary veins in relation to the Superior and Inferior LA lesions.

[0022] Figure 16 is a schematic diagram of a view of the human heart showing the location of the Sub-LAA lesion.

DETAILED DESCRIPTION

[0023] The embodiments described herein relate to the provision of systems, devices and methods for performing minimally invasive interventional treatment of atrial fibrillation. As described herein, the present embodiments provide an improved approach to generating conduction blocking lesions in cardiac tissue where ablative energy is applied "off -pump". The dual catheter-based systems and methods described herein allow for the efficient generation of transmural lesions while maintaining versatility in generating complex lesion patterns. The dual catheter-based systems and methods described herein may be used exclusively to effectively generate the full pattern of lesions in off-pump Maze procedures, or it can be used in combination with other minimally invasive surgical and catheter based techniques. The methods, systems and devices described herein may be used to create one or more lesions, and in some embodiments the full complement of lesions, in a traditional Maze, Mini-Maze, Left-sided Maze, Maze VII or other variation of a maze-based or ablation dependent interventional treatment of AF. In some embodiments, the dual catheter-based ablation systems and methods described herein may be used in combination with any other device deliverable or otherwise positionable proximate to a tissue region for treatment through the vasculature and/or by gaining access to the pericardial space to generate the full complement of Maze lesions. For example, in a complete Maze procedure, the dual catheter-based systems or methods may be used in combination with one or more of a probe, a pair of probes, a clamp, a catheter, and a balloon-catheter.

[0024] The dual catheter-based systems and methods described herein may be utilized in a closed-chest procedure using a minimally invasive access technique, such as, small left mini- thorocotomy, scope, and the like. The dual catheter-based systems and methods described herein may be performed using any surgical or electrophysiological technique or any combination therefore.

[0025] Several embodiments described herein relate to methods, systems and devices where a first catheter is provided endocardially and aligned with an epicardially provided catheter along the line of a desired lesion to provide ablative energy to the epicardial surface, the endocardial surface, or both surfaces of the heart wall. In some embodiments, a surgeon watches the placement of the epicardially provided catheter endoscopically, for example through a subxiphoid scope. In some embodiments, the endocardial catheter and/or the epicardial catheter are provided through a lumen in the scope or through a thoracic incision. In some embodiments, the endocardial catheter may be provided to the lesion site through an access point in the heart, for example through right or left atrial appendage. In some embodiments, the endocardial catheter may be provided to the lesion site through various vessels, for example, the catheter may gain access to the endocardial space through the aorta (accessed through the femoral artery), the superior vena cava (accessed through the subclavian veins) and the inferior vena cava (accessed through the femoral vein). In some embodiments, the epicardial catheter is inserted into the pericardium, in the subxiphoid position, and navigated to a position outside the heart near the atrial surface.

[0026] In some embodiments, the catheters comprise one or more magnets, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more magnets, that may be utilized to align the catheters on opposite sides of the heart wall, and then secure the catheters to each other across the heart wall. These magnets may be permanent magnets or selectively activated electromagnets. In some embodiments, each electromagnet may be energized and thus magnetized singly, independently of the other magnets, so as to allow greater control in the positioning and alignment of the catheters and/or in the amount of pressure exerted by the catheters on the intervening tissue due to the attractive force. In some embodiments, the electromagnets may be energized sequentially such that the attractive forces "zip" the catheters together. The endocardial catheter, being pressed to the endocardial wall of the atrium, serves to insulate the atrial wall from the cooling/warming effect of the significant blood flow in the atrium, thus ensuring that the ablation proceeds without hindrance from the thermal protection provided by the normal blood flow.

[0027] Either catheter, or both catheters, may be configurable so that they can be shaped to correspond to the desired lesion curvature. In some embodiments, a system for creating a transmural lesion comprises a first catheter comprising a distal segment configured to correspond to a desired lesion curvature that is relatively stiff and non-compliant with the heart and a second catheter comprising a distal segment that is relatively flexible and configured to conform to the tissue surface in response to an attractive force emitted by the first catheter, wherein the desired lesion curve corresponds to any one of the Maze lesions. In some embodiments, the first catheter is placed endocardially and the second catheter is placed epicardially. In some embodiments, the first catheter is placed epicardially and the second catheter is placed endocardially. In some embodiments, the endocardial catheter is positioned as desired at the lesion site and is then operable to magnetically attract the epicardial catheter into the proper position. In some embodiments, the epicardial catheter is positioned as desired at the lesion site and is then operable to magnetically attract the endocardial catheter into the proper position. Attraction between the two catheters holds the catheters in the proper position for the creation of the lesion, monitoring of the development of that lesion, and checking the completeness of the lesion. The two catheters can be repositioned and operated to create all the lesions that are desired in the atria or elsewhere in the heart.

[0028] Either catheter, or both catheters, may be an ablation catheter, operable to create transmural lesions with ablative energy or by chemical ablation. The ablation catheter may be operable to apply ablation energy to the heart tissue along the entire ablative surface of the catheter, or the ablation catheter may be operable to apply ablation energy to the heart tissue along a selected portion of the ablative surface. The ablative energy provided may come from any source capable of damaging cardiac tissue to generate conduction-blocking scar tissue. For example, the ablative energy may be cryogenic energy, high intensity focused ultrasound (HIFU), laser energy, radiofrequency (RF) energy, heat energy and/or microwave energy. In some embodiments, lesions are formed by applying ablative energy to the epicardium. In other embodiments lesions are formed by applying ablative energy to the endocardium. In some embodiments, ablative energy may be applied to both the endocardial and epicardial surfaces, either simultaneously or sequentially. Application of ablative energy simultaneously from both sides may help promote the formation of a lesion that spans a significant portion of the thickness of the tissue. In some embodiments, tissue may be ablated using a combination of different mechanisms, as suitable for the target tissue.

[0029] The application of ablation energy (e.g., phase, magnitude, pulse sequence, etc.), type of ablation energy (e.g., radiofrequency, laser, high intensity focused ultrasound, cryogenic agents, microwave energy, heat energy, etc.), as well as the positioning and the shape and size of the ablation device may be varied according to the geometry of the tissue and the ablation profile desired. For example, in some embodiments, one or more lesions may be formed by cryogenic endocardial ablation, while one or more other lesions may be formed by epicardial application of heat energy. Alternatively, in some embodiments, one or more lesions may be formed by the endocardial application of heat energy, while one or more other lesions may be formed by cryogenic epicardial ablation. In other variations, one or more lesions may be formed by the endocardial application of HIFU, while one or more other lesions may be formed by the epicardial application of microwave energy. The type(s) of ablation energy used as well as the positioning, type and the shape and size of the ablation device may be selected to limit damage to non-target peripheral tissue.

[0030] Further optionally, a catheter may be such that it may be used for one or more of ablation guidance, supplying ablation energy, application of pressure between the catheters, temperature monitoring, protection of tissues adjacent to the lesion site, and insulation of the lesion site from arterial blood flow. In some embodiments, the endocardial catheter and/or epicardial catheter comprises a temperature sensor that is configured to detect a temperature indicative of a lesion that has reached a sufficient state of transmurality. In some embodiments, the endocardial catheter and/or epicardial catheter may include one or more sensors to monitor the operating parameters throughout the system, including for example, pressure, temperature, flow rates, volume, or the like.

[0031] After creation of each lesion, the catheter system may be used to test the integrity of the lesion to determine if it extends completely transmurally across the cardiac wall. To this end, the endocardial catheter and/or the epicardial catheter may be operable to pace and test the impedance of the heart wall (and optionally operable to serve as ground electrodes in conjunction with the epicardial catheter if the epicardial catheter is operable as a monopolar RF catheter). In some embodiments, the catheter may contain a number of electrodes, which, in combination with electrophysiology controls attached to the catheter proximal end, can be used to apply pacing energy to the cardiac wall or test the impedance of the heart wall. If it is also desired to use RF energy for ablation necessary to create the desired lesions, these electrodes may also serve as ground electrodes for RF electrodes on the endocardial catheter, or as RF electrodes (in bipolar operation between these electrodes, or in cooperation with a surface patch electrode, or in cooperation with electrodes on the endocardial catheter). If the epicardial catheter is a cryocatheter operable to create lesions with the application of cryogenic temperature to the heart wall, it is unnecessary to provide electrodes suitable for RF ablation. The electrodes can also be operated to apply pacing energy to the cardiac wall to ensure that the pacing does not affect the electrical activity of the cardiac wall, thus indicating successful created of the lesion. Where a lesion has not extended completely through the heart wall, the impedance between the electrodes will be relatively low, especially as compared to the impedance between electrodes where the lesion is completely through the wall. By comparing the impedance to normal values, and comparing the impedance between various pairs of electrodes, the appearance of the lesion at the cardiac wall can be confirmed, and the incompleteness of a lesion can be detected and remedied by application of additional ablation energy. In addition to electrodes, the endocardial catheter and/or the epicardial catheter may include temperature sensors to detect a change in heart wall temperature and thus monitor the ablative heating or cooling accomplished by the ablation means.

[0032] Figure 1 shows a heart 1 of the patient and the location of several of the left atrium lesions created in the Cox Maze procedure. Basic structures of the heart shown in this figure include the right atrium 2, the left atrium 3, the right ventricle 4 and the left ventricle 5. Catheters may be inserted into these chambers of the heart through various vessels, including the aorta 6 (accessed through the femoral artery), the superior vena cava 6a (accessed through the subclavian veins) and the inferior vena cava 6b (accessed through the femoral vein).

[0033] The following discussion will focus on specific embodiments for performing the left atrium lesion of the Cox maze VII procedure, but the procedure for producing these lesions can be used to create all the lesions of the Cox maze VII procedure, as well as other variation of the Cox maze procedure. In Figure 1, a few of the left atrium lesions of the Cox maze VII lesion set are illustrated. Cox maze lesions 7, 8 and 9 are shown on the inner wall of the left atrium. These correspond to the superior left atrial lesion (item 7) spanning the atrium over the left and right superior pulmonary vein entries into the atrium, the inferior left atrial lesion (item 8) spanning the atrium under the left and right inferior pulmonary vein entries into the atrium, and the vertical lesion (item 9) connecting the superior left atrial lesion and inferior left atrial lesion so that the right pulmonary veins are within the area defined by the lesions. Previously, these lesions have been made in the open heart procedure or with endocardial catheters.

[0034] Figures 2 and 3 illustrate an example of the placement of endocardial and epicardial catheters for the production of a transmural lesion in the left atrium of the heart. Two catheters are used in the procedure. Figure 2 shows an example of the placement of the endocardial catheter into the left atrium via the inferior vena cava into the right atrium and then transeptally into the left atrium, while Figure 3 shows the placement of the corresponding epicardial ablation catheter for the performance of the lineal lesion above the two superior pulmonary veins. As shown in Figure 2, an endocardial catheter 10 is used to establish the desired line of a lesion and hold the epicardial catheter 11 in place on the epicardial surface (the outer surface) of the left atrium. The distal segment lOd of the endocardial catheter is steerable so that it can be deflected within the endocardial space of the atrium and held firmly against the endocardial wall of the left atrium, and may be relatively stiff and non-compliant with the heart wall. This is illustrated in Figure 2, where the distal segment lOd has been configured and steered to cover the superior left atrial lesion 7. The distal segment l id of the epicardial catheter 11 is also steerable so that it can be deflected within the epicardial space surrounding the heart and held firmly against the epicardial (outside) surface of the atrium. This is shown in Figure 3, where the epicardial catheter has been inserted into the thorax of the patient and the distal segment l id has been navigated to a position outside the left atrium but proximate the distal segment of the endocardial catheter distal segment. The distal segment is inserted into the pericardium, which surrounds the heart. The pericardium may be inflated using either a gas or a liquid to separate its inner surface from the epicardium of the heart. A pericardial scope may be used for visualization. The epicardial catheter is inserted into the pericardium, in the subxiphoid position, and navigated to a position outside the heart near the atrial surface.

[0035] Both catheters may also be configurable so that they can be shaped to correspond to the desired lesion curvature. As described in more detail below in reference to Figures 4, 5, 6 and 7, the endocardial catheter and epicardial catheter are magnetized or selectively magnetizable (with electromagnets) so that the attract each other through the myocardium (the wall of the atrium). Either catheter, or both catheters, may be an ablation catheter, operable to create transmural lesions with RF energy (bipolar or monopolar), microwave, laser, or cryoablation. In some embodiments, the endocardial catheter is operable to magnetically attract the epicardial catheter, and operable to pace and test the endocardial surface of the heart, (and optionally operable to serve as ground electrodes in conjunction with the epicardial catheter if the epicardial catheter is operable as a monopolar RF catheter) while the epicardial catheter is operable to magnetically attract the endocardial catheter, and operable to ablate heart tissue along the line of the catheter. [0036] Figures 4, 5, 6 and 7 illustrate one embodiment of the apposition of the epicardial catheter and endocardial catheter and the process of aligning the catheters. Figure 4 shows the relationship of the epicardial catheter and the endocardial catheter in preparation for creation of the lesion above the pulmonary veins. Figure 5 demonstrates how the magnets are used to position the two catheters in the correct position. Figure 6 shows the two catheters held in proper position for the creation of the lesion, monitoring of the development of that lesion, and checking the completeness of the lesion.

[0037] In Figure 4, the distal segment lOd of the endocardial catheter 10 has been inserted into the left atrium 3, and the distal segment has been configured (curved to match the superior left atrial lesion) and steered to locate the distal segment along the desired line of the superior left atrial lesion. The steering and bending of the distal segment may be accomplished with pull wires, bending ribbons, deflection tubes and any other such conventional steering and bending means.

[0038] The distal segment lOd of the endocardial catheter 10 includes a number of magnets 12p, 12i and 12d (proximal, intermediate, and distal) disposed within or on the outer surface of the distal segment, of sufficient power to attract a magnet on the outside of the heart, across the wall 13 of the atrium. These magnets may be permanent magnets or selectively activated electromagnets (that is, each electromagnet may be energized and thus magnetized singly, independently of the other magnets on the distal segment). The system and method is illustrated with three magnets, but any number of magnets may be used. The distal segment of the endocardial catheter also includes a number of electrodes 14a, b, c, d and e (shown in Figure 7). These electrodes, in combination with electrophysiology controls attached to the catheter proximal end, can be used to apply pacing energy to the atrial wall, test the impedance of the heart wall. These electrodes may also serve as ground electrodes for RF electrodes on the epicardial catheter, or as RF electrodes (in bipolar operation between these electrodes, or in cooperation with a surface patch electrode, or in cooperation with electrodes on the epicardial catheter).

[0039] Also shown in the embodiment of Figure 4 is the distal segment l id of the epicardial catheter 11. As illustrated, this distal segment has been inserted through transthoracic access ports so that the distal segment is proximate the distal segment lOd of the endocardial catheter. The distal segment l id of the epicardial catheter includes a number of magnets 15p, 15i and 15d (proximal, intermediate, and distal) disposed within or on the outer surface of the distal segment, of sufficient power to attract a magnet on the inside of the heart (any one of the magnets on the endocardial catheter), across the wall 13 of the atrium. These magnets may be permanent magnets or selectively activated electromagnets (that is, each electromagnet may be energized and thus magnetized singly, independently of the other magnets on the distal segment). The distal segment of the epicardial catheter may also include a number of electrodes 16a, b, c, d and e (shown in Figure 7. These electrodes, in combination with electrophysiology controls attached to the catheter proximal end, can be used to apply pacing energy to the atrial wall or test the impedance of the heart wall. If it is also desired to use RF energy for ablation necessary to create the desired lesions, these electrodes may also serve as ground electrodes for RF electrodes on the endocardial catheter, or as RF electrodes (in bipolar operation between these electrodes, or in cooperation with a surface patch electrode, or in cooperation with electrodes on the endocardial catheter). If the epicardial catheter is a cryocatheter operable to create lesions with the application of cryogenic temperature to the heart wall, it is unnecessary to provide electrodes suitable for RF ablation.

[0040] Figures 4, 5 and 6 also illustrate an embodiment of the method of co-locating the endocardial catheter and the epicardial catheter on opposite sides of the atrial wall 13 but along the same line, established by the endocardial catheter. In the embodiment shown in Figure 4, a first pair of magnets, such as electromagnet 12d on the endocardial catheter and electromagnet 15p on the epicardial catheter, are energized when they are proximate each other on opposite sides of the atrial wall. This will fix them in place relative to each other. This is shown in Figure 4. In Figure 5, with the first point of magnetic attachment and fixation established between magnets 12d and 15p, a second pair of magnets is energized. As shown, magnets 12i and 15i are energized to attract each other. Some additional steering or bending of the epicardial catheter may be necessary to bring the magnet 15i into proximity to magnet 12i. Next, in Figure 6, with the first and second points of magnetic attachment established, magnets 12p and 15d are energized to attract each other and fix the corresponding portions of the catheter relative to each other and the atrial wall. [0041] In some embodiments, fixation is performed under fluoroscopy, with an interventional radiologist controlling the endocardial catheter to fix it along the desired lesion line and a cardiac surgeon operating the epicardial catheter to locate it proximate the endocardial catheter and, after fixation is achieved, operate an ablating means on the epicardial catheter to create the desired lesion. After proper placement is confirmed, the epicardial catheter is operated to create the desired lesion.

[0042] Figure 7 illustrates an embodiment of the use of electrodes on the endocardial catheter to test the atrial wall to determine if a lesion created by the system is complete. As shown in Figure 7, ablative energy is applied through the epicardial catheter to create a lesion 17. While ablating energy is applied, the endocardial catheter remains fixed in place due to the magnetic attraction established by the magnets. The endocardial electrode, being pressed to the endocardial wall of the atrium, serves to insulate the atrial wall from the cooling/warming effect of the significant blood flow in the atrium, thus ensuring that the ablation proceeds without hindrance from the thermal protection provided by the normal blood flow. Also, the electrodes on the endocardial catheter are operated to test the atrial wall. The electrodes can be used to sense the impedance of the heart wall, which will increase significantly when the wall surface is ablated, indicating that the intended lesion extends completely through the atrial wall. The electrodes can also be operated to apply pacing energy to the atrial wall to ensure that the pacing does not affect the electrical activity of the atrial wall, thus indicating successful created of the lesion. For example, between electrodes 14a and 14b, the lesion has not extended completely through the heart wall. Consequently, the impedance between the two electrodes will be relatively low, especially as compared to the impedance between electrodes 14c and 14d, where the lesion is completely through the wall. By comparing the impedance to normal values, and comparing the impedance between various pairs of electrodes, the appearance of the lesion at the atrial wall can be confirmed, and the incompleteness of a lesion can be detected. In addition to electrode, the endocardial catheter and the epicardial catheter may include temperature sensors to detect a change in heart wall temperature and thus monitor the ablative heating or cooling accomplished by the ablation means.

[0043] The two catheters can be repositioned and operated to create all the lesions that are desired in the atria or elsewhere in the heart. [0044] The endocardial catheter may contain multiple recording electrodes, multiple pacing electrodes, multiple impedance detectors, and multiple thermocouples (thermistors) along its length so that the transmurality and contiguity of each lesion can be documented throughout the length of the lesion. This is made possible by securing this endocardial monitoring catheter in its proper relationship to the epicardial ablation catheter using the multiple magnets in both catheters. After the completion of each lesion and documentation that it is both transmural and contiguous with no gaps, the securing magnets will be de-magnetized enough to allow both catheters to be repositioned for the next lesion.

[0045] Permanent magnets may be used on both the epicardial and endocardial catheters, but the use of electromagnets on at least one of the catheters will provide easier control of the sequence of magnetic matching of the corresponding magnets of each catheter, and thus facilitate the desired sequential magnet connection between pairs of magnets. Also, while the lesions of the left atrium and the Cox maze VII procedure has been used to illustrate the system and method of making lesions, they may be employed to create transmural lesions for any treatment of the heart. Where appropriate, the method and system may be adopted for treatment of other hollow body organs where transmural lesions are created for therapeutic effect, such as the esophagus, with one catheter positioned inside the hollow body organ and the other catheter positioned outside the hollow body organ.

[0046] Several embodiments described herein relate to devices systems and methods for performing a minimally invasive interventional procedure, comprising a pattern of conduction-blocking lesions in the heart that is effective for the treatment of all forms of AF. The pattern of Maze VII lesions creates a planned "maze" of scar tissue that serves as barriers, blocking the formation of aberrant macro-reentry circuits and guiding irregular cardiac electrical signals back to more normal pathways. (See, e.g., Figure 8.) The pattern of conduction-blocking lesions of the Maze VII procedure comprises a first conduction-blocking lesion extending along a line between the inferior and superior vena cava (See, e.g., Figure 9), a second conduction- blocking lesion extending transversely across the right atrium and intersecting the first conduction-blocking lesion between the inferior and superior vena cava (See, e.g., Figure 10), a third conduction-blocking lesion extending laterally along the right atrium and intersecting the second conduction-blocking lesion (See, e.g., Figure 11), a fourth conduction-blocking lesion in the coronary sinus (See, e.g., Figure 12), a fifth conduction-blocking lesion extending along a transverse line located below the right and left inferior pulmonary veins (See, e.g., Figure 13), a sixth conduction-blocking lesion extending along a transverse line located above the right and left superior pulmonary veins (See, e.g., Figure 14), a seventh conduction-blocking lesion comprised of a plurality of lesions extending along the anterior interatrial groove proximate the origins of the right superior and inferior pulmonary veins and intersecting the fifth conduction- blocking lesion below the right inferior pulmonary vein and the sixth conduction-blocking lesion above the right superior pulmonary vein (See, e.g., Figure 15) and an eighth conduction-blocking lesion located along a line extending from the base of the left atrial appendage to a location proximate the mitral annulus (See, e.g., Figure 16). Although the lesions are labeled first, second, third, etc., this is for ease of reference and the lesions may be made in any order.

[0047] In some embodiments, a lesion along the superior to inferior vena cava may be made using a pair of catheters, in which at lest one catheter comprises an ablation member at or near its distal end. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In several embodiments, a first catheter is positioned endocardially in the desired SVC-LVC lesion pattern and a second catheter is provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. In several embodiments, a first catheter is positioned epicardially in the desired SVC-LVC lesion pattern and a second catheter is provided endocardially and aligned with the first catheter through magnetic attraction through the myocardium. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion. In some embodiments, placement of the epicardial catheter is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a catheter may be placed through a lumen in the scope. [0048] In some embodiments, a lesion along the superior to inferior vena cava may be made using a single catheter comprising an ablation member at or near its distal end. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In several embodiments, a catheter delivers ablation energy from the endocardium transmurally to the epicardium. Optionally, formation of the lesion may be visually observed endoscopically on the epicardial surface. In some embodiments, lesion formation is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a probe may be placed through a lumen in the scope such that it may be used for one or more of ablation guidance, supplying ablation energy, application of pressure between the working portion of the ablation member, temperature monitoring, and protection of tissues adjacent to the lesion site.

[0049] In some embodiments for producing a superior to inferior vena cava lesion, a probe comprising an ablation member may be used to create the lesion. In some embodiments, the probe may create a transmural lesion from the epicardium. In some embodiments, the probe may be passed through a lumen in a scope placed through a subxiphoid access incision or may be passed through a secondary access port in the thorax or abdomen. In some embodiments, the probe may create a transmural superior to inferior vena cava lesion from the endocardium by being placed through a further access point in the heart, for example an access point in the right atrial appendage using means such as a purse string suture or valved sheath to prevent or minimize the escape of blood from the beating heart.

[0050] In some embodiments for producing a superior to inferior vena cava lesion, a clamp comprising an ablation member is used to create a superior to inferior vena cava lesion. In some embodiments, the clamp is configured to comprise two opposing jaws that when actuated may open or close to apply pressure there between. One jaw of the clamp may be placed along the surface of the endocardium through a further access point in the heart, for example an access point in the right atrial appendage and optionally blood is prevented from escaping the beating heart using means such as a purse string suture. The other jaw of the clamp may remain external to the heart along the surface of the epicardium such that the wall of the heart is positioned between the jaws of the clamp and subjected to pressure when the clamp jaws are in a closed position. In one embodiment, both clamp jaws comprise an ablation member configured such that a transmural lesion may be made by application of ablation energy to both the internal and external surfaces of the heart adjacent the clamp. In another embodiment, one jaw comprises an ablation member and the other jaw comprises a temperature sensor that is configured to detect a temperature indicative of a lesion that has reached a sufficient state of transmurality. In several embodiments, the jaws of a clamp configured to generate a superior to inferior vena cava lesion may be a configured to allow for actuation independent of one another.

[0051] Optionally, in any of the aforementioned embodiments, a probe comprising an ablation member may be used to finalize the superior to inferior vena cava lesion so as to reduce the possibility of making contact of adjacent tissue, such as the phrenic nerve. In some embodiments, the probe may create the transmural lesion from the epicardium and may optionally be passed through a lumen in a scope placed through a subxiphoid access incision or may be passed through a secondary access port in the thorax or abdomen. In some embodiments, the probe may further comprise an insulation sheath or other such similar adjustable means configured to control the amount of surface area exposed on the working portion of the ablation member such that precise control of ablation lesion formation may be achieved in areas where sensitive tissue may be adjacent to the targeted lesion zone. By way of a non-limiting example, if an insulating sheath were actuated to expose only the very most tip of the ablation member, fine tuning or touching up of the superior to inferior vena cava lesion may be accomplished with increased precision in a manner analogous to the drawing of a line on paper using a marking pen and a fine-tipped pen.

[0052] Several embodiments relate to systems, methods and apparatus for creating a right-side "T" lesion roughly perpendicular to the superior to inferior vena cava lesion. The right-side "T" lesion may be created using the same or similar variety of systems and apparatus used to create the superior to inferior vena cava lesion.

[0053] In some embodiments, a "T" lesion may be made using a pair of catheters, in which at lest one catheter comprises an ablation member at or near its distal end. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In several embodiments, a first catheter, which may optionally be configured to steer or otherwise be turned about 90 degrees to the direction to the axis of the vena cava so that it may be positioned to create a lesion across the right side of the heart transverse to the vena cava about mid way between the superior and inferior vena cava and traversing the right side of the heart, is positioned endocardially in the desired T lesion pattern and a second catheter is provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. In several embodiments, a first catheter, which may optionally be configured to steer or otherwise be turned about 90 degrees to the direction to the axis of the vena cava so that it may be positioned to create a lesion across the right side of the heart transverse to the vena cava about mid way between the superior and inferior vena cava and traversing the right side of the heart, is positioned epicardially in the desired SVC-LVC lesion pattern and a second catheter is provided endocardially and aligned with the first catheter through magnetic attraction through the myocardium. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion. In some embodiments, placement of the epicardial catheter is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a catheter may be placed through a lumen in the scope. Further optionally, a probe may be placed through a lumen in the scope such that it may be used for one or more of ablation guidance, supplying ablation energy, application of pressure between the working portion of the ablation member, temperature monitoring, and protection of tissues adjacent to the lesion site.

[0054] In some embodiments, a single endocardial catheter, comprising an ablation member at or near its distal end, may be used to conduct ablation energy to the targeted tissue to create the right-side T lesion. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In some embodiments, a catheter comprising an ablation member delivers ablation energy from the endocardium transmurally to the epicardium. The catheter may optionally be configured to steer or otherwise be turned about 90 degrees to the direction to the axis of the vena cava so that it may be positioned to create a lesion across the right side of the heart transverse to the vena cava, most preferably about mid way between the superior and inferior vena cava and traversing the right side of the heart. Optionally, formation of the lesion may be visually observed endoscopically on the epicardial surface. In some embodiments, lesion formation is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a probe may be placed through a lumen in the scope such that it may be used for one or more of ablation guidance, supplying ablation energy, application of pressure between the working portion of the ablation member, temperature monitoring, and protection of tissues adjacent to the lesion site.

[0055] In some embodiments, a probe comprising an ablation member may be used to create the right-side T lesion. In some embodiments, the probe may create a transmural lesion from the epicardium. In some embodiments, the probe may be passed through a lumen in a scope placed through a subxiphoid access incision or may be passed through a secondary access port in the thorax or abdomen. In some embodiments, the probe may create the transmural lesion from the endocardium by being placed through a further access point through the heart, for example, the probe may be placed through an access point in the right atrial appendage, optionally using means such as a purse string suture or valved sheath to prevent the escape of blood from the beating heart. In some embodiments, the probe may be configured to steer or be bent so that the roughly 90 degree turn from the vena cava may be accomplished. In some embodiments, the probe may be constructed of a flexible material that allows the probe to be bent to the preferred shape and then inserted into the vena cava to navigate transverse from the vena cava across the right side of the heart to make the desired lesion. In some embodiments, the probe may be pre- configured in a shape that allows the probe to be inserted into the vena cava to navigate transverse from the vena cava across the right side of the heart to make the desired lesion.

[0056] In some embodiments, a clamp comprising an ablation member may be used to create the right-side T lesion. In some embodiments, the clamp may be passed through a secondary access port in the thorax. In some embodiments, the clamp is configured to comprise two opposing jaws that when actuated may open or close to apply pressure there between. One jaw of the clamp may be placed along the surface of the endocardium through a further access point through the heart, for example through an access point in the right atrial appendage, optionally using means such as a purse string suture that may prevent the escape of blood from the beating heart. The other jaw of the clamp may remain external to the heart along the surface of the epicardium such that the wall of the heart is positioned between the jaws of the clamp and subjected to pressure when the clamp jaws are actuated closed. In one embodiment, both clamp jaws comprise an ablation member and are configured such that a transmural lesion may be made from both the internal and external surfaces of the heart adjacent the clamp. In another embodiment, the clamp is configured such that one jaw comprises an ablation member and the other jaw comprises a temperature sensor that is configured to detect a temperature indicative of a lesion that has reached a sufficient state of transmurality. In some embodiments, the jaws of a clamp configured to create the right-side T lesion may be a configured to allow for actuation independent of one another. The clamp may optionally be configured to steer or be bent so that the right-side T lesion may be made at about 90 degrees from the point of access. In some embodiments, the clamp may be constructed of a flexible material that allows the clamp to be bent to the preferred shape and then inserted and positioned across the right side of the heart to make the desired lesion. In some embodiments, the clamp may pre-configured in the desired shape to create the right-side T lesion.

[0057] Several embodiments relate to systems, methods and apparatus for creating a right-side lateral lesion roughly parallel to the superior to inferior vena cava. The right-side lateral lesion may be created using the same or similar variety of systems and apparatus used to create the superior to inferior vena cava lesion.

[0058] In some embodiments, a right-side lateral lesion may be made using a pair of catheters, in which at lest one catheter comprises an ablation member at or near its distal end. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In several embodiments, a first catheter, which may be configured to steer or otherwise be turned about 180 degrees to the direction to the axis of the vena cava so that it may be positioned to create a lesion extending roughly perpendicular from the right-side T and terminating in proximity to the right atrial appendage, is positioned endocardially in the desired RA Lateral lesion pattern and a second catheter is provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. In several embodiments, a first catheter, which may be configured to steer or otherwise be turned about 180 degrees to the direction to the axis of the vena cava so that it may be positioned to create a lesion extending roughly perpendicular from the right-side T and terminating in proximity to the right atrial appendage, is positioned epicardially in the desired RA Lateral lesion pattern and a second catheter is provided endocardially and aligned with the first catheter through magnetic attraction through the myocardium. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion.

[0059] In some embodiments, a single endocardial catheter comprising an ablation member at or near its distal end, may be used to conduct ablation energy to the targeted tissue to create the right-side lateral lesion. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In some embodiments, a catheter comprising an ablation member delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, the catheter may be configured to steer or otherwise be turned about 180 degrees to the direction to the axis of the vena cava so that it may be positioned to create a lesion extending roughly perpendicular from the right-side T and terminating in proximity to the right atrial appendage. Optionally, formation of the lesion may be visually observed endoscopically on the epicardial surface. In some embodiments, lesion formation is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a probe may be placed through a lumen in the scope such that it may be used for one or more of ablation guidance, supplying ablation energy, application of pressure between the working portion of the ablation member, temperature monitoring, and protection of tissues adjacent to the lesion site.

[0060] In some embodiments, a probe comprising an ablation member may be used to create the right-side lateral lesion. In some embodiments, the probe may create a transmural lesion from the epicardium. In some embodiments, the probe may be passed through a lumen in a scope placed through a subxiphoid access incision or may be passed through a secondary access port in the thorax or abdomen. In some embodiments, the probe may create the transmural lesion from the endocardium by being placed through a further access point through the heart, for example, the probe may be placed through an access point in the right atrial appendage, optionally using means such as a purse string suture or valved sheath to prevent the escape of blood from the beating heart. The probe may be configured to steer or be bent so that the roughly 180 degree turn from the vena cava may be accomplished. In some embodiments, the probe may be constructed of a flexible material that allows the probe to be bent to the preferred shape and then inserted into the vena cava to navigate transverse from the vena cava across the right side of the heart and about 180 degrees to make the desired lesion vertically along the right atrium. In some embodiments, the probe may be preconfigured in the desired shape and then inserted into the vena cava to navigate transverse from the vena cava across the right side of the heart and about 180 degrees to make the desired lesion vertically along the right atrium.

[0061] In some embodiments, a clamp comprising an ablation member may be used to create the right-side lateral lesion. In some embodiments, a clamp configured to create the right-side lateral lesion may be passed through a secondary access port in the thorax. In some embodiments, the clamp is configured to have two opposing jaws that when actuated may open or close to apply pressure there between. One jaw of the clamp may be placed along the surface of the endocardium through a further access point through the heart, for example through an access point in the right atrial appendage, optionally using means such as a purse string suture to prevent the escape of blood from the beating heart. The other jaw of the clamp may remain external to the heart along the surface of the epicardium such that the wall of the heart is positioned between the jaws of the clamp and subjected to pressure when the clamp jaws are actuated closed. In one embodiment, both clamp jaws comprise an ablation member configured such that a transmural lesion may be made from both the internal and external surfaces of the heart adjacent the clamp. In another embodiment one jaw comprises an ablation member and the other jaw comprises a temperature sensor configured to detect a temperature indicative of a lesion that has reached a sufficient state of transmurality. In some embodiments, the jaws of a clamp configured to create the right-side lateral lesion may be configured to allow for actuation independent of one another. The clamp may optionally be configured to steer or be bent so that the right-side lateral lesion may be made at about 180 degrees from the point of access. In some embodiments, the clamp may be constructed of a flexible material that may allow the clamp to be bent to the preferred shape and then inserted and positioned across the right side of the heart to make the right-side lateral lesion. In some embodiments, the clamp pre-configured in the desired shape to make the right-side lateral lesion.

[0062] Several embodiments relate to systems, methods and apparatus for placing a lesion inside the coronary sinus.

[0063] In some embodiments, a lesion inside the coronary sinus may be made using a pair of catheters, in which at lest one catheter comprises an ablation member at or near its distal end. In some embodiments, catheter access may be through the vena cava or other such suitable route amenable to catheter navigation. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In several embodiments, a first catheter, which may be configured to comprise an expanding member that may be expanded to contact the inner lumen of the coronary sinus, is positioned endocardially in the coronary sinus and a second catheter is provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. The expanding member may be in any form sufficient to contact and conform to the shape of the coronary sinus inner lumen. In some embodiments, the expanding member may be an inflatable balloon configured to transmit the ablative energy for the creation of a lesion in the coronary sinus. In other embodiments, the expanding member may be an expandable framework, such as a basket or cage, configured to transmit the ablative energy for the creation of a lesion in the coronary sinus. The ablation member may be of any length suitable for sufficient ablative energy transfer. In some embodiments, the ablation member may be of a length that minimizes the number of ablation cycles necessary to form a lesion of sufficient surface area to block macro-reentrant circuits. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion. In some embodiments, placement of the epicardial catheter is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a catheter may be placed through a lumen in the scope.

[0064] In some embodiments, a single catheter comprising an ablation means at its distal end may be used to create a lesion inside the coronary sinus. In some embodiments, catheter access may be through the vena cava or other such suitable route amenable to catheter navigation. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. The ablation member may be further configured to comprise an expanding member that may be expanded to contact the inner lumen of the coronary sinus. The expanding member may be in any form sufficient to contact and conform to the shape of the coronary sinus inner lumen. In some embodiments, the expanding member may be an inflatable balloon configured to transmit the ablative energy for the creation of a lesion in the coronary sinus. In other embodiments, the expanding member may be an expandable framework, such as a basket or cage, configured to transmit the ablative energy for the creation of a lesion in the coronary sinus. The ablation member may be of any length suitable for sufficient ablative energy transfer. In some embodiments, the ablation member may be of a length that minimizes the number of ablation cycles necessary to form a lesion of sufficient surface area to block macro-reentrant circuits. Optionally, formation of the lesion may be visually observed endoscopically on the epicardial surface. In some embodiments, lesion formation is visually observed via a scope placed through a subxiphoid access incision.

[0065] In some embodiments, a probe comprising an ablation member may be used for the creation of a lesion in the coronary sinus. In some embodiments, the probe may create the lesion by being placed through an access point in the heart, for example, the probe may be placed through an access point in the right atrial appendage, optionally using means such as a purse string suture or valved sheath to prevent the escape of blood from the beating heart. The probe may be configured to comprise an expanding structure such as a balloon, a basket, a coil, a loop, or the like, that is configured to deliver ablation energy of the types described herein to the targeted tissue to create a lesion in the coronary sinus. In some embodiments, the probe is configured to comprise an expanding structure such as a balloon, a basket, a coil, a loop, or the like, that is configured to deliver a cryogen ablative energy source to the targeted tissue to create a lesion in the coronary sinus.

[0066] In the embodiments described herein, left-side lesions may be formed using a variety of surgical and electrophysiological tools. In some embodiments, access is gained to the heart for creating left-side lesions through a small thorocotomy incision located at an interstitial location between the left-side rib bones of the chest.

[0067] In some embodiments, lesions are placed traversing the left side of the heart, with one lesion traversing a path extending across the left and right inferior pulmonary veins, and a second lesion traversing a path extending across the left and right superior pulmonary veins (the "PV lesions"). In some embodiments, the PV lesions intersect at a point in proximity to the left atrial appendage and then diverge along a superior and inferior path of traverse. In some embodiments, an additional lesion may be placed to intersect the PV lesions at a point in proximity to the left atrial appendage. An ablation member may be used to conduct ablation energy to the targeted tissue to create the PV lesions. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen.

[0068] In some embodiments, the PV lesions may be made using a pair of catheters, in which at least one catheter comprises an ablation member at or near its distal end. In several embodiments, a first catheter is positioned in the left atrium endocardially to either traverse a path extending across the left and right inferior pulmonary veins (for the Inferior LPV lesion) or to traverse a path extending across the left and right superior pulmonary veins (for the Superior LPV lesion) via the inferior vena cava into the right atrium and then transeptally into the left atrium. A second catheter is then provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion. In some embodiments, placement of the epicardial catheter is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a catheter may be placed through a lumen in the scope.

[0069] In some embodiments where the PV lesions are made using a pair of catheters, the endocardial catheter may gain access to the left ventricle through an access point in the wall of the heart. In some embodiments, a endocardial catheter configured to create the PV lesions may be passed through a left-side thorocotomy and placed along the surface of the endocardium either traversing a path extending across the left and right inferior pulmonary veins (for the Inferior LPV lesion) or traversing a path extending across the left and right superior pulmonary veins (for the Superior LPV lesion) through a further access point through the heart, for example the endocardial catheter may be placed through an access point in the left atrial appendage, optionally using means such as a purse string suture or valved sheath to prevent the escape of blood from the beating heart. The epicardial catheter is provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion. After ablation is complete, the catheters are repositioned to create the alternate LPV lesion. In some embodiments, placement of the epicardial catheter is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a catheter may be placed through a lumen in the scope.

[0070] In some embodiments, the PV lesions may be formed using a clamp comprising an ablation member. In some embodiments, a clamp configured to create the PV lesions may be passed through a left-side thorocotomy. The clamp may be configured to comprise two opposing jaws that when actuated may open or close to apply pressure there between. One jaw of the clamp may be placed along the surface of the endocardium through a further access point through the heart, for example the clamp may be placed through an access point in the left atrial appendage, optionally using means such as a purse string suture to prevent the escape of blood from the beating heart. The other jaw of the clamp may remain external to the heart along the surface of the epicardium such that the wall of the heart is positioned between the jaws of the clamp and subjected to pressure when the clamp jaws are actuated closed. In one embodiment, both clamp jaws comprise an ablation member such that a transmural lesion may be made from both the internal and external surfaces of the heart adjacent the clamp. In another embodiment one jaw comprises an ablation member and the other jaw comprises a temperature sensor configured to detect a temperature indicative of a lesion that has reached a sufficient state of transmurality. In some embodiments, the jaws of the clamp configured to create the PV lesions may be configured to allow for actuation independent of one another. Optionally, the jaws of the clamp may further comprise magnets that contribute to the clamping pressure such that lesion formation may be aided by the additional pressure.

[0071] In some embodiments, a probe comprising an ablation member may be used for formation of the PV lesions. In some embodiments, the probe may create a transmural lesion from the endocardium. In some embodiments, the probe may be placed through an access point through the heart, for example, the probe may be placed through an access point in the left atrial appendage, optionally using means such as a purse string suture or valved sheath that may prevent the escape of blood from the beating heart.

[0072] Optionally, formation of the lesion may be visually observed endoscopically on the epicardial surface. In some embodiments, lesion formation is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a probe may be placed through a lumen in the scope such that it may be used for one or more of ablation guidance, supplying ablation energy, application of pressure between the working portion of the ablation member, temperature monitoring, and protection of tissues adjacent to the lesion site.

[0073] In several embodiments described herein, the right pulmonary veins are further isolated by forming lesions that close off the divergent portion of the PV lesions (the "RPV lesions"). An ablation member may be used to conduct ablation energy to the targeted tissue to create the RPV lesions. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen.

[0074] In some embodiments, a lesion connecting the superior left atrial lesion and inferior left atrial lesion may be made using a pair of catheters, in which at lest one catheter comprises an ablation member at or near its distal end. In several embodiments, a first catheter is positioned endocardially in a configuration that connects the superior left atrial lesion and inferior left atrial lesion to isolate the pulmonary veins and a second catheter is provided epicardially and aligned with the first catheter through magnetic attraction through the myocardium. In several embodiments, a first catheter is positioned epicardially in a configuration that connects the superior left atrial lesion and inferior left atrial lesion to isolate the pulmonary veins and a second catheter is provided endocardially and aligned with the first catheter through magnetic attraction through the myocardium. In some embodiments, the epicardial catheter is positioned on the epicardium proximate the anterior interatrial groove near the origin of the right pulmonary veins such that a lesion may be created along the perimeter of the pulmonary veins to complete the RPV lesions and a second catheter is provided endocardially and aligned with the first catheter through magnetic attraction through the myocardium and ablation energy is applied to the epicardial and/or endocardial surface, thereby forming a contiguous lesion extending from a point proximate the left atrial appendage which traverses superior and inferior to the pulmonary veins and which forms a closed loop along the origins of the right pulmonary veins. In some embodiments, the endocardial catheter delivers ablation energy from the endocardium transmurally to the epicardium. In some embodiments, an epicardial catheter delivers ablation energy from the epicardium transmurally to the endocardium. In some embodiments both catheters deliver ablation energy across the cardiac wall. Optionally, the catheters may monitor the formation of the lesion. In some embodiments, placement of the epicardial catheter is visually observed via a scope placed through a subxiphoid access incision. Further optionally, a catheter may be placed through a lumen in the scope. In some embodiments, a probe comprising an ablation member at its distal end may be placed through a lumen of an endoscope placed through a subxiphoid access point and used for the formation of the RPV lesions. In some embodiments, the probe is positioned on the epicardium proximate the anterior interatrial groove near the origin of the right pulmonary veins such that a lesion may be created along the perimeter of the pulmonary veins to complete the RPV lesions, thereby preferably forming a contiguous lesion extending from a point proximate the left atrial appendage which traverses superior and inferior to the pulmonary veins and which forms a closed loop along the origins of the right pulmonary veins.

[0075] In some embodiments, a balloon catheter may be positioned and inflated to expand the ostium of each of the right pulmonary veins so as to temporarily diminish the heat sink effect of cavitary blood passing through the vein in proximity to the RPV lesion as it is being formed. Secondarily, the resultant expansion of the ostium from the inflation of the balloon may expose a larger and more accessible surface area of the epicardium where the probe is placed for RPV lesion formation. Any acceptable means for catheter access may be used. In some embodiments, access is gained through the left atrial appendage using means such as a purse string suture or valved sheath to prevent the escape of blood from the beating heart.

[0076] In some embodiments for forming the RPV lesion, a probe may be configured to comprise a shaped end that facilitates the shaping of the RPV lesion from the endocardium. In some embodiments, the probe distal portion may comprise a loop-like feature or plurality of loop-like features to aid in providing the desired contact pressure against the endocardium. In some embodiments, the probe distal end may be exposed from a sheath such that the loop-like feature or features are unconstrained and allowed to be formed by mechanical action or thermal action if a shape memory alloy is used. In the instance of a single loop-like feature, the feature provides locating force against the endocardium and also provides the working ablative surface for lesion formation. In the instance of a plurality of loop-like features, one or more features may be used for locating and securement while one or more features may be used for ablation. Hooks, barbs or other such means may be further used to aid in securement in any endocardial probe embodiment.

[0077] In several embodiments described herein, a lesion is formed along the left atrial appendage. In some embodiments, an ablation probe comprising an ablation member at its distal portion is placed on the surface of the endocardium to form the lesion. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. The lesion may serve to isolate the electrical path along the left atrial appendage.

[0078] In several embodiments for forming the left atrial appendage lesion, the probe may either be steerable or curved to conform along the left atrial appendage access point to the mitral annulus. In some embodiments, the probe may be configured to steer or be bent so that a roughly 180 degree turn may be accomplished. In some embodiments, the probe may be constructed of a flexible material that allows the probe to be bent to the preferred shape prior to insertion by either manually forming the desired bend or by having a bend that increases as the probe tip is unrestrained from a sheath. In some embodiments, the probe tip may be steered by means that are controlled from the distal end by the operator.

[0079] Optionally, for any portion of the procedure, pericardium may be insufflated with a gas or biocompatible fluid such that the pericardium is lifted away from the epicardium to improve the viewing of lesion formation when observed by endoscope. [0080] Several embodiments relate to a catheter comprising an ablation member at its distal end comprised of an ablation surface with an ablation energy source providing energy to the ablation surface. The ablation energy may be of any type sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen. In some embodiments, the distal end of the catheter further comprises one or more permanent magnets or selectively activated electromagnets (that is, each electromagnet may be energized and thus magnetized singly, independently of the other magnets on the distal segment).

[0081] In some embodiments, the distal portion of the catheter may further comprise an expanding structure that comprises the ablation surface or a plurality of ablation surfaces. In some embodiments, the expanding structure may expand by thermal action, such as by use of shape memory materials, or may be mechanically actuated. In some embodiments, the expandable structure may be comprised of any of a balloon, one or more of coils or loops, a basket, a cage, a flange or bell-like structure and the like.

[0082] Several embodiments described herein relate to a cryosurgical clamp comprising an ablation member configured to create ablation lesions leading to formation of conduction-blocking scar tissue at the lesion site. In some embodiments, the clamp is configured to have two opposing jaws that when actuated may open or close to apply pressure there between. In some embodiments, one or more jaws of the clamp are configured to comprise an ablation member configured to conduct ablation energy to the targeted tissue to create the desired lesion. Ablation energy supplied by the ablation member may be of any source sufficient to damage the target tissue leading to formation of conduction-blocking scar tissue at the lesion site. For example, the source of ablation energy may be selected from the group consisting of radio frequency (RF) energy, microwave energy, thermal energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some embodiments, the source of ablation energy is a cryogen.

[0083] In some embodiments, the cryosurgical clamp may have a thin shaft so that it may be introduced though a very small opening, such as that of a mini-thorocotomy in the chest wall or an endoscope. For example, when closed, the clamp may be inserted through a very small chest wall incision. After it is positioned inside the chest, the clamp jaws may be opened wide enough to preferably be able to clamp large structures. In some embodiments, the clamp may be manipulated by the clamp's handle which is well outside the chest.

[0084] In some embodiments, the clamp may be bipolar, having an ablative surface on the opposing surfaces of the two jaws. Alternately, the clamp may be monopolar with an ablative surface on one jaw. In some embodiments, the clamp may be configured such that one or both jaws further comprise a temperature sensor that is configured to detect a temperature indicative of a lesion that has reached a sufficient state of transmurality.

[0085] In several embodiments described herein, a steerable cryoprobe may be used to perform one or more of the lesions of the procedure described herein. In some embodiments, the probe may be comprised of an ablation surface at its distal portion. In some embodiments, the probe may further comprise a retractable sheath or shaft which surrounds the ablation surface. In some embodiments, the ablation surface is sized to provide a desirable combination of access size, stiffness, and working surface area. In some embodiments, the inner cryoprobe may be freely moveable through the handle and shaft so that it can be lengthened or withdrawn completely inside the shaft.

[0086] In some embodiments, the shaft of the instrument may provide sufficient stiffness to provide strength when pressure is applied for surface contact during lesion formation while remaining malleable so that it can be shaped. In one embodiment, steering or shaping may be performed by hand before insertion and use.

[0087] Also described here are kits for performing any of the interventional procedures described herein. One variation of a kit may comprise a first ablation device configured to place one or more of: a lesion extending along a line between the inferior and superior vena cava, a lesion extending transversely across the right atrium and intersecting the lesion between the inferior and superior vena cava, and a lesion extending laterally along the right atrium and intersecting the transverse lesion along the right atrium; and one or more of a second ablation device configured to place a lesion in the coronary sinus; a third ablation device configured to place one or more of a lesion extending along a transverse line located below the right and left inferior pulmonary veins and a lesion extending along a transverse line located above the right and left superior pulmonary veins; a fourth ablation device configured to place a plurality of lesions extending along the anterior interatrial groove proximate the origins of the right superior and inferior pulmonary veins; and a fifth ablation device configured to place a lesion extending from the base of the left atrial appendage to a location proximate the mitral annulus, wherein the aforementioned ablation devices comprise at least one ablation member configured to deliver ablative energy to the targeted tissue, and wherein the ablative energy is selected from the group consisting of RF energy, microwave energy, cryogenic energy, laser energy, and high-frequency ultrasound energy and wherein one or more of the aforementioned ablation devices are selected from a group consisting of: a dual catheter system, a clamp, a surgical probe and a single catheter. In some variations, the kit comprises a first and a second device as described above. In some variations, the kit comprises a first, a second and a third device as described above. In some variations, the kit comprises a first, a second, a third, and a fourth device as described above. In some variations, the kit comprises a first, a second, a third, a fourth and a fifth devices as described above. In certain variations, any of the kits described above may further comprise one or more of: a surgical clip to be placed at the base of the LAA, a surgical scope and an inflatable balloon configured to be positioned and inflated proximate the internal ostium of a pulmonary vein.

[0088] One variation of a kit may comprise a first ablation device configured to place one or more of: a lesion extending along a line between the inferior and superior vena cava, a lesion extending transversely across the right atrium and intersecting the lesion between the inferior and superior vena cava, and a lesion extending laterally along the right atrium and intersecting the transverse lesion along the right atrium, wherein the first ablation device is an ablation catheter comprising a distal portion having an ablation member configured to deliver ablative energy to the targeted tissue or a dual-catheter system configured to deliver ablative energy to the targeted tissue; and one or more of a second ablation device configured to place a lesion in the coronary sinus, wherein the second ablation device is an ablation catheter comprising an expandable structure a distal portion, wherein the expandable structure comprises an ablation member; a third ablation device configured to place one or more of a lesion extending along a transverse line located below the right and left inferior pulmonary veins and a lesion extending along a transverse line located above the right and left superior pulmonary veins, wherein the third ablation device is an ablation clamp having two opposing jaws comprising at least one ablation surface on one jaw; a fourth ablation device configured to place a plurality of lesions extending along the anterior interatrial groove proximate the origins of the right superior and inferior pulmonary veins, wherein the fourth ablation device is a flexible ablation probe comprising a flexible sheath and a flexible ablation member; and a fifth ablation device configured to place a lesion extending from the base of the left atrial appendage to a location proximate the mitral annulus wherein the fifth ablation device is a flexible ablation probe comprised of a flexible sheath and flexible ablation member; and wherein the aforementioned ablation members are configured to deliver ablative energy to the targeted tissue, wherein the ablative energy is selected from the group consisting of RF energy, microwave energy, cryogenic energy, laser energy, and high-frequency ultrasound energy. In some variations, the kit comprises a first and a second device as described above. In some variations, the kit comprises a first, a second and a third device as described above. In some variations, the kit comprises a first, a second, a third, and a fourth device as described above. In some variations, the kit comprises a first, a second, a third, a fourth and a fifth devices as described above. In certain variations, any of the kits described above may further comprise one or more of: a surgical clip to be placed at the base of the LAA, a surgical scope and an inflatable balloon configured to be positioned and inflated proximate the internal ostium of a pulmonary vein.

[0089] While some embodiments of the devices and methods have been described in reference to the environment in which they were developed, they are merely illustrative of principles and are provided by way of example and for clarity of understanding, those of skill in the art will recognize that a variety of modification, adaptations and changes may be employed. The elements of the various embodiments may be incorporated into each of the other species to obtain the benefits of those elements in combination with such other species, and the various beneficial features may be employed in embodiments alone or in combination with each other. Other embodiments and configurations may be devised without departing from the spirit of the inventions and the scope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A method of securing an epicardial catheter to the heart, said method comprising: inserting into an endocardial space an endocardial catheter having a magnet disposed on or within a distal segment of said endocardial catheter;

inserting an epicardial catheter having a magnet disposed on or within a distal segment of said endocardial catheter into the epicardial space surrounding heart, such that the epicardial catheter distal segment is proximate the endocardial catheter distal segment, such the magnet disposed on or within a distal segment of the endocardial catheter magnetically attracts the magnet disposed on or within the distal segment of the epicardial catheter across the wall of the heart.

2. A method of treating atrial fibrillation in the heart of a patient, said method comprising the steps of:

providing an epicardial catheter having a distal segment adapted for insertion into the thorax of a patient, said endocardial catheter having at least one magnet disposed on or within the distal segment, said epicardial catheter having means for creating a lesion in the heart wall, said means disposed on or within the distal segment of the epicardial catheter;

providing an endocardial catheter having a distal segment adapted for insertion into an atrium of the patient's heart, said endocardial catheter having at least one magnet disposed on or within the distal segment;

disposing the epicardial catheter distal segment proximate an epicardial surface of the heart;

disposing the endocardial catheter distal segment proximate an endocardial surface of the heart;

magnetically attracting the epicardial catheter distal segment to the endocardial catheter distal segment;

operating the means for creating a lesion while the epicardial catheter distal segment and the endocardial catheter distal segment are magnetically attracted to each other.

3. A method of treating atrial fibrillation in the heart of a patient by creating one or more Maze lesions, said method comprising the steps of:

4. A method of treating atrial fibrillation in the heart of a patient by creating Cox maze lesions, said method comprising the steps of:

providing an epicardial catheter having a distal segment adapted for insertion into the thorax of a patient, said endocardial catheter having a plurality of electromagnets disposed on or within the distal segment thereof, said epicardial catheter having means for creating a lesion in the heart wall, said means disposed on or within the distal segment of the epicardial catheter;

providing an endocardial catheter having a distal segment adapted for insertion into an atrium of the patient's heart, said endocardial catheter having a plurality of electromagnets disposed on or within the distal segment thereof; disposing the epicardial catheter distal segment proximate an epicardial surface of the heart, along an intended line of a transmural lesion to be created;

disposing the epicardial catheter distal segment proximate an endocardial surface of the heart, in apposition to the endocardial distal segment;

energizing a first electromagnet on the endocardial catheter distal segment, and energizing a first electromagnet on the epicardial catheter distal segment to magnetically attract a first pair of electromagnets to each other across the heart wall;

energizing a second electromagnet on the endocardial catheter distal segment, and energizing a second electromagnet on the epicardial catheter distal segment to magnetically attract a second pair of electromagnets to each other across the heart wall; operating the means for creating a lesion while the epicardial catheter distal segment and the endocardial catheter distal segment are magnetically attracted to each other.

5. The method of claims 1, 2 3, or 4, further comprising the steps of: testing the impedance of the heart wall through electrodes disposed on the endocardial catheter distal segment.

6. The method of claims 1, 2 3, or 4, further comprising the steps of: testing the electrical conduction of the heart wall through electrodes disposed on the endocardial catheter distal segment.

7. A system for creating transmural lesions in the wall of the heart of the patient, said system comprising:

a first catheter having a distal segment, said distal segment of the first catheter having an ablation member and one or more electromagnets disposed on or within the distal segment; and

a second catheter having a distal segment, said distal segment of the second catheter having an ablation member and one or more magnetic elements chosen from permanent magnets, paramagnetic elements, or ferromagnetic elements disposed on or within the distal segment; and

a means for operating the electromagnets of the first catheter to selectively attract magnets on the first catheter to magnetic elements on the second catheter.

8. A system for creating transmural lesions in the wall of the heart of the patient, said system comprising:

a first catheter having a distal segment, said first catheter having a plurality of electromagnets disposed on or within the distal segment thereof; and

a second catheter having a distal segment, said first catheter having a plurality of electromagnets disposed on or within the distal segment thereof; and

means for operating the electromagnets of the first and second catheter to selectively attract electromagnets on the first catheter to electromagnets on the second catheter;

means for creating a lesion in the wall of the heart through the first catheter.

9. The system of claim 7 or 8, wherein the first catheter is a cryogenic catheter operable to apply cryogenic cooling to the heart wall.

10. The system of claim 7 or 8, wherein the first catheter is a RF ablation catheter operable to radiofrequency energy to the heart wall.

11. A method of creating transmural lesions for the purpose of treating atrial fibrillation comprising the steps of:

placing a lesion with an ablation device, the lesion extending along a line between the inferior and superior vena cava;

placing a lesion with an ablation device, the lesion extending transversely across the right atrium and intersecting the lesion between the inferior and superior vena cava; placing a lesion with an ablation device, the lesion extending laterally along the right atrium and intersecting the transverse lesion along the right atrium;

placing a lesion with an ablation device, the lesion being placed in the coronary sinus;

placing a lesion with an ablation device, the lesion extending along a transverse line located below the right and left inferior pulmonary veins;

placing a lesion with an ablation device, the lesion extending along a transverse line located above the right and left superior pulmonary veins;

placing a plurality of lesions with an ablation device, the plurality of lesions extending along the anterior interatrial groove proximate the origins of the right superior and inferior pulmonary veins and intersecting the transverse lesions above and below the pulmonary veins; and

placing a lesion with an ablation device, the lesion located along a line extending from the base of the left atrial appendage to a location proximate the mitral annulus.

12. The method of claim 11 wherein the ablation device for placing the lesion between the inferior and superior vena cava comprises a first and second ablation catheter, wherein the first ablation catheter comprises a distal segment, said distal segment comprising an ablation member and one or more electromagnets disposed on or within the distal segment, and wherein the second ablation catheter comprises a distal portion having an ablation member and one or more magnetic elements chosen from permanent magnets, paramagnetic elements, or ferromagnetic elements disposed on or within the distal segment.

13. The method of claim 11 or 12 wherein the ablation device for placing the lesion in the coronary sinus is an ablation catheter having a distal portion comprising an expandable structure comprising an ablation member.

14. The method of claim 11, 12, or 13 wherein the ablation device for placing the plurality of lesions along the origin of the right inferior and superior pulmonary veins is a flexible ablation probe comprising a flexible sheath and flexible ablation member.

15. The method of claim 11, 12, 13 or 14 wherein the ablation device for placing the lesion from the base of the left atrial appendage to a location proximate the mitral annulus is a flexible ablation probe comprising a flexible sheath and flexible ablation member.

16. The method of any one of claims 11-15, wherein the ablation member is configured to deliver ablation energy selected from the group consisting of: RF energy, microwave energy, cryogenic energy, laser energy, and high-frequency ultrasound energy.

17. The method of any one of claims 11-16, further comprising placing a surgical clip at the base of the LAA to occlude the LAA.