MXPA00011661A - Augmentation of muscle contractility by biphasic stimulation - Google Patents
Augmentation of muscle contractility by biphasic stimulationInfo
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- MXPA00011661A MXPA00011661A MXPA/A/2000/011661A MXPA00011661A MXPA00011661A MX PA00011661 A MXPA00011661 A MX PA00011661A MX PA00011661 A MXPA00011661 A MX PA00011661A MX PA00011661 A MXPA00011661 A MX PA00011661A
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- phase
- stimulation
- muscle
- amplitude
- muscle tissue
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Abstract
Augmentation of electrical conduction and contractility by biphasic stimulation of muscle tissue. A first stimulation phase has a first phase polarity, amplitude, and duration. The first stimulation phase, which acts as a conditioning mechanism, is administered at no more than a maximum subthreshold amplitude. A second stimulation phase has a second polarity, amplitude, and duration. The two phases are applied sequentially. Contrary to current thought, anodal stimulation is applied as the first stimulation phase, followed by cathodal stimulation as the second stimulation phase. In this fashion, pulse conduction through muscle is improved, together with an increase in contractility. Furthermore, this mode of biphasic stimulation reduces the electrical energy required to elicit contraction. In addition, the conditioning first stimulation phase decreases the stimulation threshold by reducing the amount of electrical current required for the second stimulation phase to elicit contraction. The muscle tissue encompassed by the present invention includes skeletal (striated) muscle, cardiac muscle, and smooth muscle.
Description
INCREASE OF THE. MUSCLE CONTRACTIBILITY BY BIPHYSICAL STIMULATION
FIELD OF THE INVENTION The present invention relates in general to a method for the stimulation of muscle tissue. In particular, the present invention relates to a method for stimulating muscle tissue with biphasic waves that reduce the electrical energy required to induce contraction. BACKGROUND OF THE INVENTION The function of the cardiovascular system is vital for survival. Through the blood circulation, the tissues of the body obtain the necessary nutrients and oxygen, and discard waste substances. In the absence of circulation, the cells begin to undergo irreversible changes that lead to death. The muscular contractions of the heart are the driving force behind the circulation. In the heart muscle, the muscle fibers are interconnected in networks that spread in all directions through the heart. When any portion of this network is stimulated, a wave of depolarization passes to all its parts and the entire structure contracts as a unit. Before a muscle fiber can be
Ref: 125394 stimulated to contract, its membrane must be polarized. A muscle fiber generally remains polarized until it is stimulated by some change in its environment. A membrane can be stimulated electrically, chemically, mechanically or by a change in temperature. The minimum force of stimulus needed to induce a contraction is known as the stimulus threshold. The maximum amplitude of stimulus that can be administered without inducing a contraction is the maximum subthreshold amplitude. When the membrane is electrically stimulated, the pulse amplitude required to induce a response depends on a number of factors. The first is the duration of the current flow. Since the total load transferred is equal to the current amplitude for the duration of the pulse, the increase in the duration of the stimulus is associated with a decrease in the threshold current amplitude. Secondly, the percentage of applied current that actually passes through the membrane varies inversely proportional to the size of the electrode. Third, the percentage of applied current that actually passes through the membrane varies directly in proportion to the proximity of the electrode to the tissue. Fourth, the pulse amplitude required to induce a response depends on the moment of stimulation within the excitability cycle.
Groups and fibers of specialized cardiac muscle tissue exist in a large part of the heart. This tissue comprises the cardiac conduction system and serves to initiate and distribute the depolarization waves throughout the myocardium. Any interference or blockage in the conduction of the cardiac impulse, can cause an arrhythmia or a marked change in the pulse or rhythm of the heart. - Sometimes a patient who suffers from a driving disorder, can be helped by an artificial pacemaker. Each device contains a small electric battery stimulator. When the artificial pacemaker is installed, the electrodes are usually threaded through the veins to the right ventricle or into the right atrium and right ventricle, and the stimulator is implanted under the skin in the shoulder or abdomen. The wires are implanted in close contact with the heart tissue. Then, the pacemaker transmits rhythmic electrical impulses to the heart and the myocardium responds rhythmically contracting. Implantable medical devices for marking the passage of the heart are well known in the art and have been used in humans since about the mid-1960s. Cathodic or anodic current can be used to stimulate the myocardium. However, it is thought that the anodic current is not clinically useful. The cathodic current comprises electrical pulses of negative polarity. This type of current depolarizes the cell membrane by discharging the capacitor of the membrane and directly reduces the membrane potential to the threshold level. The cathodic current, by directly reducing the remaining membrane potential to the threshold, it has from one half to one third of the threshold current in the late diastole compared to the anodic current. The anodic current comprises electrical pulses of positive polarity. The effect of the anodic current is to hyperpolarize the membrane at rest. When the anodic pulse is suddenly terminated, the membrane potential returns to the resting level, it shoots up to the threshold and a propagated response occurs. The use of anodic current to stimulate the myocardium is generally discouraged due to its higher stimulation threshold, which leads to the use of a higher current, resulting in the battery of the implanted device running out and having a shorter longevity. Additionally, the use of the anodic current for cardiac stimulation is discouraged due to the suspicion that the anodic contribution to depolarization, particularly at higher voltages, may contribute to an arrhythmogenesis.
Virtually all artificial pacemakers are manufactured using stimuli of negative polarity or, in the case of bipolar systems, the cathode is closer to the myocardium than the anode. When the use of anodic current is described, it is usually a charge of minute magnitude used to dissipate the residual charge at the electrode. This does not affect the condition of the myocardium itself. Such use was described in the North American Patent No. 4,543,956 of Herscovici. The use of a three-phase wave has been described in US Patents Nos. 4,903,700 and 4,821,724 of Whigham et al. and in U.S. Patent 4,343,312 to Cals et al. In this case, the first and third phases have nothing to do with the myocardium itself, but only have the purpose of affecting the surface of the electrode. Thus, the load applied in these patients is very low amplitude. Finally, biphasic stimulation is described in U.S. Patent 4,402,322 to Duggan. The goal of this description is to produce a double voltage without the need for a large capacitor in the output circuit. The phases of the biphasic stimulation described are of equal magnitude and duration. What is needed is an improved mechanism to stimulate muscle tissue, where induced contraction increases and tissue damage adjacent to the electrode decreases. A better myocardial function is obtained through the biphasic pacemaker of the present invention. The combination of cathode and anodic pulses, either stimulating or of a conditioning nature, preserves the improved conduction and contractibility of the anodic pacemaker, while eliminating the inconvenience of increasing the stimulus threshold. The result is a depolarization wave with a higher propagation speed. This increased velocity of propagation results in a superior cardiac contraction, leading to an improvement in blood flow. A better stimulus at a lower voltage level also causes the reduction of energy consumption and increases the life of the pacemaker batteries. As with the cardiac muscle, the striated muscle can also be stimulated electrically, chemically, mechanically or by a change in temperature. When the muscle fiber is stimulated by a motor neuron, the neuron transmits an impulse that activates all the muscle fibers under its control, that is, those muscle fibers that are in its motor unit. Depolarization in the membrane region stimulates adjacent regions to depolarize as well, resulting in a depolarization wave traveling on the membrane in all directions away from the stimulus site. So, when a motor neuron transmits an impulse, all the muscle fibers of its motor unit are stimulated to contract simultaneously. The minimum force to induce a contraction is called the threshold stimulus. Once this level of stimulation is reached, it is generally thought that increasing the level will not increase the contraction. Additionally, as the muscle fibers of each muscle are organized into motor units and each motor unit is controlled by a single motor neuron, all the muscle fibers of a motor unit are stimulated at the same time. However, the entire muscle is controlled by many different motor units that respond to different stimulus thresholds. So, when a given stimulus is applied to a muscle, some motor units can respond, while others do not. The combination of the cathodic and anodic pulses of the present invention also provides better contraction of striated muscle, in cases where muscle stimulation is indicated due to neurological or muscular damage. When the nerve fibers have been damaged due to trauma or disease, the muscle fibers of the regions supplied by the damaged nerve fiber tend to suffer atrophy and deteriorate. A muscle that can not be exercised can decrease to half its normal size in a few months. When there is no stimulus, not only the muscle fibers will diminish in size, but they will fragment and degenerate, and they will be replaced by connective tissue. Through electrical stimulation, one can maintain muscle tone, so that, by healing or regenerating the nerve fiber, there is still viable muscle tissue and, in this way, the overall regenerative process is improved and favored. The stimulation of the striated muscle can also serve to conserve the neural path, so that, by healing the nerve fibers associated with the stimulated tissue, the patient "remembers" how to contract that particular muscle. The intensification of the contraction of the striated muscle is obtained through the biphasic stimulation of the present invention. The combination of cathode and anodic pulses, either stimulating or conditioning, results in the contraction of a greater number of motor units at a lower voltage level, thus causing a superior muscular response. Finally, biphasic stimulation according to the present invention may be desirable to stimulate smooth muscle tissue, such as those muscles responsible for the movements that push the food through the digestive tract, the muscles contracting the blood vessels and those that empty the urinary bladder. For example, appropriate stimulation could rectify the difficulties associated with incontinence. SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide better electrical stimulation of the cardiac muscle. Another objective of the present invention is to extend the life of the batteries of implantable electrical stimulation devices. Another objective of the present invention is to obtain effective muscle stimulation at a lower voltage level. Another objective of the present invention is to provide stimulation of muscle tissue, particularly striated muscle. Another objective of the present invention is to provide contraction of a greater number of motor muscle units at a lower voltage level. Another objective of the present invention is to provide contraction of a greater number of motor muscle units at a lower level of electric current.
A method and apparatus for muscle stimulation in accordance with the present invention includes the administration of biphasic stimulation to muscle tissue, wherein both cathodic and anodic pulses are administered. In accordance with another aspect of the present invention, the stimulation is administered to the muscle tissue to induce a muscular response. The stimulation can be administered directly or indirectly to the muscle tissue, where indirect administration includes stimulation through the skin. By using the present invention, lower ls of electrical energy (voltage and / or current) are required to reach the stimulus threshold, compared to conventional stimulation methods. The muscle tissue that can benefit from stimulation in accordance with the present invention includes skeletal muscle (striatum), cardiac muscle and smooth muscle. The electronic components required for the implantable stimulation devices necessary for practicing the method of the present invention are known to those skilled in the art. Current implantable stimulation devices are capable of being programmed to deliver a variety of pulses, including those described herein.
In addition, the electronic components required for indirect muscle stimulation are also known to those skilled in the art and are easily modified for practicing the method of the present invention. The method and apparatus of the present invention comprises a first and a second stimulation phase, wherein each stimulation phase has a polarity, amplitude, shape and duration. In a preferred embodiment, the first and second phases have different polarities. In an alternative mode, the two phases are of different amplitude. In a second alternative mode, the two phases are of different duration. In a third alternative mode, the first phase is a phase in the form of a shock wave. In a fourth alternative mode, the amplitude of the first phase is increased. In a preferred alternative embodiment, the first stimulation phase is an anodic pulse at a maximum subthreshold amplitude of long duration and the second stimulation phase is a cathode pulse of short duration and high amplitude. It is noted that the aforementioned alternative modalities can be combined in different ways. It should also be noted that these alternative modalities are intended to be presented by way of examples only and not in a limiting manner. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic representation of an anodic biphasic phase advance stimulation. Figure 2 is a schematic representation of a two-phase cathodic phase advance stimulation. Figure 3 is a schematic representation of an anodal stimulation of low l and long duration phase advance, followed by a conventional cathodic stimulation. Figure 4 is a schematic representation of an anodic stimulation of phase advance of low l in increase and long duration, followed by a conventional cathodic stimulation. Figure 5 is a schematic representation of an anodic stimulation of low l and short duration phase advance, administered in series, followed by a conventional cathodic stimulation. Figure 6 is a graph of the cross-fiber conduction velocity versus the step duration resulting from the biphasic anodic phase advance pulse. Figure 7 is a graph of the conduction velocity parallel to the fiber versus the duration of the step resulting from the biphasic anodic pulse of phase advance. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the biphasic electrical stimulation of muscle tissue. Figure 1 illustrates the biphasic electrical stimulation wherein a first stimulation phase comprising the anodic stimulus 102, it is administered with an amplitude 104 and a duration 106. This first stimulation phase is immediately followed by a second stimulation phase comprising a cathodic stimulation 108 of equal intensity and duration. Figure 2 illustrates biphasic electrical stimulation, wherein a first stimulus phase comprising a cathodic stimulus 202 having an amplitude 204 and a duration 206 is administered. This first stimulation phase is immediately followed by a second stimulation phase comprising an anodic stimulus 208 of equal intensity and duration. Figure 3 illustrates a preferred embodiment of the present invention, wherein a first stimulation phase comprising a low level, long duration anodic stimulation 302 having an amplitude 304 and a duration 306 is administered. This first stimulation phase is followed immediately by a second stimulation phase comprising a cathode stimulus 308 of conventional intensity and duration. In an alternative embodiment of the present invention, the anodic stimulus 302 is at a maximum subthreshold amplitude. In still another alternative embodiment of the present invention, the anodic stimulus 302 is less than three volts. In another alternative embodiment of the present invention, the anodic stimulus 302 has a duration of about two to eight milliseconds. In yet another alternative embodiment of the present invention, the cathode stimulus 308 is of short duration. In yet another embodiment of the present invention, the cathode stimulus 308 is from about 0.3 to 0.8 milliseconds. In yet another alternative embodiment of the present invention, the cathode stimulus 308 is of high amplitude. In another alternative embodiment of the present invention, the cathode stimulus 308 is in a range of approximately three to twenty volts. In yet another alternative embodiment of the present invention, the cathode stimulus 308 has a duration of less than 0.3 milliseconds and a voltage greater than 20 volts. In another alternative embodiment of the present invention, the cathode stimulus 308 lasts as long as 6.0 milliseconds and has a voltage as low as 200 millivolts. In the manner described by these modalities, as well as those alterations and modifications that are obvious upon reading the present description, a maximum membrane potential is achieved without activation in the first stimulation phase. Figure 4 illustrates an alternative preferred embodiment of the present invention wherein a first stimulation phase, comprising the anodic stimulus 402, is administered in a period 404 with the raising of the intensity level 406. The form of the elevation of the level of intensity 406 can be linear or non-linear and the slope can vary. This anodic stimulation is immediately followed by a second stimulation phase comprising the cathode stimulus 408 of conventional intensity and duration. In an alternative embodiment of the present invention, the anodic stimulus 402 is raised to a maximum subthreshold amplitude. In still another alternative embodiment of the present invention, the anodic stimulus 402 rises to a maximum amplitude that is less than three volts. In another alternative embodiment of the present invention, the anodic stimulus 402 has a duration of about two to eight milliseconds. In yet another alternative embodiment of the present invention, the cathode stimulus 408 is of short duration. In another alternative embodiment of the present invention, the cathode stimulus 408 is from about 0.3 to 0.8 milliseconds. In yet another alternative embodiment of the present invention, the cathode stimulus 408 is of high amplitude. In another alternative embodiment of the present invention, the cathode stimulus 408 is in the range of about three to twenty volts. In yet another alternative embodiment of the present invention, the cathode stimulus 408 has a duration less than 0.3 milliseconds at a voltage greater than twenty volts. In another alternative embodiment of the present invention, the cathodic stimulus 408 lasts as long as 6.0 milliseconds and has a voltage as low as 200 millivolts. In the manner described by these embodiments, as well as those alterations and modifications that may be obvious upon reading the present description, a maximum membrane potential is reached without activation in the first stimulation phase. Figure 5 illustrates the biphasic electrical stimulation wherein a first stimulation phase comprises a series 502 of anodic pulses, being administered at an amplitude 504. In one embodiment, the rest period 506 is of equal duration to the stimulation period 508 and is administered to the amplitude of the baseline. In an alternative embodiment, the rest period 506 has a duration different from the stimulation period 508 and is administered at the amplitude of the baseline. The rest period 506 occurs after each stimulation period 508, with the exception that a second stimulation phase comprising the cathodic stimulus 510 of conventional intensity and duration, follows immediately after the completion of the 502 series. In an alternative embodiment of In the present invention, the total charge transferred through the 502 series of anodic stimuli is at the maximum subthreshold level. In another alternative embodiment of the present invention, the cathodic stimulus 510 is of short duration. In yet another alternative embodiment of the present invention, the cathodic stimulus 510 is from about 0.3 to 0.8 milliseconds. In another alternative embodiment of the present invention, the cathodic stimulus 510 is of high amplitude. In yet another alternative embodiment of the present invention, the cathodic stimulus 510 is in the approximate range of 3 to 20 volts. In another alternative embodiment of the present invention, the cathodic stimulus 510 has a duration less than 0.3 milliseconds at a voltage greater than 20 volts. In another alternative embodiment of the present invention, the cathodic stimulus 510 lasts as long as 6.0 milliseconds and has a voltage as low as 200 millivolts. EXAMPLE 1 The characteristics of stimulation and propagation of the myocardium in isolated hearts were studied, using pulses of different polarities and phases. The experiments were carried out in five isolated hearts of rabbit with perfusion of Langendorff. The conduction velocity in the epicardium was measured using an array of bipolar electrodes. Measurements were made between six millimeters and nine millimeters from the stimulation site. The transmembrane potential was recorded using a floating intracellular microelectrode. The following protocols were examined: monophasic cathodic pulse, monophasic anodic pulse, biphasic cathodic phase advance pulse and biphasic anodic phase advance pulse. Table 1 describes the conduction velocity transverse to the direction of the fibers for each stimulation protocol administered, with stimulations of three, four and five volts and a pulse of two milliseconds in duration. TABLE 1 Transverse Conduction Speed to the Direction of the Fibers, 2 msec duration
Table 2 describes the speed of; conduction along the direction of the fiber for each stimulation protocol administered, with stimulations of three, four and five volts and pulses of two milliseconds in duration. TABLE 2 Conduction Speed along the Fiber Direction, 2 msec duration
It was found that differences in conduction velocities between monophasic cathodic, monophasic anodic, biphasic cathodic phase advance and biphasic anodic phase advance stimuli were significant (p <0.001). From the transmembrane potential measurements, the maximum upward stroke
((dV / dt) max) of the action potentials was found to correlate well with changes in the conduction velocity in the longitudinal direction. For a four-volt pulse lasting two milliseconds, the (dV / dt) max was 63.5 1 2.4 V / sec for the cathode pulse and 75.5 1 5.6 V / sec for the anodic pulses. EXAMPLE 2 The effects of various passage protocols on cardiac electrophysiology were analyzed using isolated rabbit hearts with Langendorff perfusion. The stimulation was applied to the heart to a rectangular pulse of constant voltage. The following protocols were examined: monophasic anodic pulse, monophasic cathodic pulse, biphasic anodic pulse of phase advance and biphasic cathodic pulse of phase advance. The administered voltage was increased in stages of one volt from one to five volts for both anodic stimulation and cathodic stimulation. The duration increased in two millisecond increments from two to ten milliseconds. The epicardial conduction velocities were measured along and transversely to the direction of the fibers of the left ventricle, at a distance between three and six millimeters from the free wall of the left ventricle. Figures 6 and 7 illustrate the effects of the duration of the stimulation pulses and the administered stimulation protocol on driving speeds. Figure 6 illustrates the speeds measured between three and six millimeters transverse to the direction of the fiber. In this region, the cathodic monophasic stimulation 602 demonstrates the slowest conduction velocity for each pulse duration of stimulation tested. This was followed by the anopic monophasic stimulation 604 and the cathodic biphasic stimulation of phase advance 606. The fastest conduction velocity was demonstrated with the biphasic anodic stimulation of phase advance 608. Figure 7 illustrates the speeds measured between three and six millimeters, parallel to the direction of the fiber. In this region, cathodic monophasic stimulation 702 demonstrated the slowest conduction velocity for each pulse duration of stimulation tested. The results of the speed of the anodic monophasic stimulation 704 and the biphasic stimulation of phase advance 706 are similar to those obtained with the anodic monophasic stimulation, but show slightly higher speeds. The fastest conduction velocity was demonstrated by the biphasic anodic phase advancement of 708. In one aspect of the present invention, an electrical stimulus was administered to the heart muscle. The component of anodic stimulation of biphasic electrical stimulation, increases cardiac contractibility and hyperpolarizes the tissue before its excitation, causing a faster impulse conduction, a greater intracellular calcium release and obtaining a superior cardiac contraction. The component of cathodic stimulation eliminates the drawbacks of anodic stimulation, obtaining an effective cardiac stimulation at a lower voltage level compared to what would be necessary for anodic stimulation alone. This, in turn, extends the life of the pacemaker battery and reduces tissue damage. In a second aspect of the present invention, biphasic electrical stimulation was administered to a cardiac blood mixture.; that is, the blood that enters and that is in the surroundings of the heart. This makes cardiac stimulation possible without the need to place electrical cables in intimate contact with the cardiac tissue, thus decreasing the possibility of damaging this tissue. The stimulation threshold of the biphasic stimulation administered through the blood mixture is in the same range as the standard stimuli delivered directly to the cardiac muscle. Through the use of biphasic electrical stimulation to the cardiac blood mixture, therefore, it is possible to achieve a better cardiac contraction without contraction of the skeletal muscle, without damage to the cardiac muscle or adverse effects on the blood mixture. In a third aspect of the present invention, biphasic electrical stimulation is applied to striated (skeletal) muscle tissue. The combination of anodic and cathodic stimulation results in the contraction of a greater number of muscular motor units at lower levels of voltage and / or electric current, obtaining a better muscular response. The benefits of the present invention are achieved when there is direct stimulation, as well as when the stimulation is indirect (through the skin). The benefits can be achieved in physical therapy and in the context of muscle rehabilitation, for example, stimulating the muscles over time while waiting for damaged nerves to regenerate. In a fourth aspect of the present invention, biphasic electrical stimulation is applied to smooth muscle tissue. Visceral smooth muscle is found in the walls of hollow visceral organs such as the stomach, intestines, urinary bladder and uterus. The fibers of the smooth muscles are capable of stimulating each other. Thus, once a fiber is stimulated, the wave of depolarization that moves on its surface can excite the adjacent fibers, which, in turn, stimulate others. The benefits of such stimulation can be achieved, for example, in situations where incontinence has been caused by trauma or disease. Having thus described the basic concept of the present invention, it will be readily apparent to those skilled in the art that the detailed description was presented as an example only and is not limiting. Technicians in the field may make various alterations, improvements and modifications, which are not expressly indicated here. These modifications, alterations and improvements can be suggested here and are within the scope of the present invention. In addition, the stimulating pulses described herein are within the capabilities of the existing electronics, with appropriate programming. The biphasic stimulation provided in the present invention may be desirable in additional situations where electrical stimulation is indicated; such as, stimulation of nervous tissue and stimulation of bone tissue. Accordingly, the present invention will be limited only by the following claims and equivalents thereto. With regard to this date, the best method known by the applicant to carry out said invention is the conventional one for the manufacture of the objects to which it refers.
Claims (32)
- CLAIMS Having described the invention as an antecedent, the content of the following claims is claimed as property: 1. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase amplitude is increased from a baseline value to a second value.
- 2. The muscle tissue stimulation method with biphasic waves according to claim 1, characterized in that the first phase amplitude is equal to or less than a maximum subthreshold amplitude.
- 3. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase amplitude is increased from a baseline value to a second value and wherein the absolute value of the second value is equal to the absolute value of the second phase amplitude.
- 4. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase of stimulation further comprises a series of stimulating pulses of predetermined amplitude, polarity and duration.
- 5. The method for stimulating muscle tissue with biphasic waves according to claim 4, characterized in that the first stimulation phase also comprises a series of rest periods.
- 6. The method for stimulating muscle tissue with biphasic waves according to claim 5, characterized in that the application of the first stimulation phase further comprises applying a resting period of a baseline amplitude after at least one stimulation pulse.
- 7. The method for stimulating muscle tissue with biphasic waves according to claim 6, characterized in that the rest period is of equal duration to the duration of the stimulating pulse.
- 8. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase polarity is positive and the maximum subthreshold amplitude is approximately 0.5 to 3.5 volts.
- 9. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase duration is at least as long as the second phase duration and the first phase duration is approximately 1 to 9 milliseconds.
- 10. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase durition, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase duration is at least as long as the second phase duration and the second phase duration is approximately 0.2 to 0.9 milliseconds.
- 11. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase durcition, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the second phase amplitude is from about 2 to 20 volts.
- 12. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the second phase duration is less than 0.3 milliseconds and the second phase amplitude is greater than 20 volts.
- 13. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the second value is at a maximum subthreshold amplitude.
- 14. The method for stimulating muscle tissue with biphasic waves according to claim 13, characterized in that the subthreshold amplitude. maximum is approximately 0.5 to 3.5 volts.
- 15. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the first phase duration is at least as long as the second phase duration.
- 16. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the first phase duration is approximately 1 to 9 milliseconds.
- 17. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the second phase duration is approximately 0.2 to 0.9 milliseconds.
- 18. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the second phase amplitude is approximately 2 to 20 volts.
- 19. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the phase duration is less than 0.3 milliseconds and the second phase amplitude is greater than 20 volts.
- 20. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises: defining a first phase of stimulation with a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation; defining a second phase of stimulation with a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and applying the first phase of stimulation and the second phase of stimulation in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the stimulation to the muscle is selected from the group consisting of direct stimulation to the muscle and indirect stimulation to the muscle; and where indirect stimulation is administered through the skin.
- 21. The method for stimulating muscle tissue with biphasic waves according to claim 1, characterized in that the second phase duration is less than about 6 milliseconds and the second phase amplitude is at least 200 millivolts.
- 22. A method for stimulating muscle tissue with biphasic waves, characterized in that it comprises the steps of: defining a first phase of stimulation with a positive polarity, a first phase amplitude, a first phase form and a first phase duration, wherein the first phase amplitude is about 0.5 to 3.5 volts and the first phase duration is about 1 to 9 milliseconds; defining a second phase of stimulation with a negative polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration, wherein the second phase amplitude is approximately 2 to 20 volts and the second phase duration is approximately 0.2 to 0.9 milliseconds; and applying the first stimulation phase and the second stimulation phase in sequence to the muscle tissue, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle, and wherein the stimulation to the muscle is selected from the group consisting of direct stimulation to the muscle and indirect stimulation to the muscle.
- 23. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, defining the pulse a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase amplitude rises from a baseline value to a second value.
- 24. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase amplitude is raised from a baseline value to a second value, and wherein the absolute value of the second value is equal to the absolute value of the second phase amplitude.
- 25. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic pulse generating components that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase of stimulation further comprises a series of stimulating pulses of predetermined amplitude, polarity and duration.
- 26. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase polarity is positive and the maximum subthreshold amplitude is approximately 0.5 to 3.5 volts.
- 27. An apparatus to stimulate tissue? muscle with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase duration is at least as long as the second phase duration and the first phase duration is approximately 1 to 9 milliseconds.
- 28. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the first phase duration is at least as long as the second phase duration and the second phase duration is approximately 0.2 to 0.9 milliseconds.
- 29. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components that generate pulses that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, for preconditioning the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the second phase amplitude is from about 2 to 20 volts.
- 30. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, defining the pulse a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the second phase duration is less than 0.3 milliseconds and the second phase amplitude is greater than 20 volts.
- 31. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components generating pulses that generate a pulse, defining the pulse a first phase of stimulation and defining a second phase of stimulation, wherein the first phase of stimulation has a first phase polarity, a first phase amplitude, a first phase form and a first phase duration, to precondition the muscle tissue to accept a subsequent stimulation, and wherein the second phase of stimulation has a polarity opposite to the first phase polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle; wherein the stimulation to the muscle is selected from the group consisting of direct stimulation to the muscle and indirect stimulation to the muscle; and where indirect stimulation is administered through the skin.
- 32. An apparatus for stimulating muscle tissue with biphasic waves, characterized in that it comprises: electronic components that generate pulses that generate a pulse, the pulse defining a first phase of stimulation and defining a second phase of stimulation; wherein the first stimulation phase has a positive polarity a first phase amplitude, a first phase form and a first phase duration wherein the first phase amplitude is approximately 0.5 to 3.5 volts and the first phase duration is approximately 1 to 9 milliseconds; and wherein the second phase of stimulation has a negative polarity, a second phase amplitude that is greater in absolute value than the first phase amplitude, a second phase form and a second phase duration, wherein the second phase amplitude is approximately 2 to 20 volts and the second phase duration is approximately 0.2 to 0.9 milliseconds; and cables connected to the electronic pulse generating components and which are adapted to apply the first stimulation phase and the second stimulation phase to the muscle tissue in sequence, wherein the muscle tissue is selected from the group consisting of striated muscle, smooth muscle and mixed muscle and wherein the stimulation to the muscle is selected from the group consisting of direct stimulation to the muscle and indirect stimulation to the muscle.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US09085360 | 1998-05-27 |
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MXPA00011661A true MXPA00011661A (en) | 2002-07-25 |
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