Source: https://patents.google.com/patent/EP0599567A2/en
Timestamp: 2019-08-17 23:40:59
Document Index: 784010085

Matched Legal Cases: ['art 104', 'art 104', 'art 104', 'art 104', 'art 104', 'Application No. 07']

EP0599567A2 - System and method for stimulating a heart having undergone cardiac myoplasty using a single-chamber pacemaker - Google Patents
EP0599567A2
EP0599567A2 EP93309258A EP93309258A EP0599567A2 EP 0599567 A2 EP0599567 A2 EP 0599567A2 EP 93309258 A EP93309258 A EP 93309258A EP 93309258 A EP93309258 A EP 93309258A EP 0599567 A2 EP0599567 A2 EP 0599567A2
EP93309258A
EP0599567A3 (en
1992-11-20 Priority to US979502 priority Critical
1992-11-20 Priority to US07/979,502 priority patent/US5328442A/en
1993-11-19 Application filed by Siemens AG, Pacesetter AB, Pacesetter Inc filed Critical Siemens AG
1994-06-01 Publication of EP0599567A2 publication Critical patent/EP0599567A2/en
1996-08-28 Publication of EP0599567A3 publication Critical patent/EP0599567A3/en
The causes of congestive heart failure are multiple. In the United States and Europe, the most common cause is coronary artery disease resulting in myocardial infarctions (heart attacks) which destroy a portion of the heart muscle, thereby weakening the heart. The heart may also be affected by a viral or other infections (such as Trypanosoma cruzi, most common in South America), toxins (the most common of which is alcohol), or unknown causes (referred to as "idiopathic"). It is estimated that there are over 100,000 new patients each year with congestive heart failure.
In recent years, it has been postulated that strong skeletal muscle tissue could be trained to repeatedly contract, and yet not fatigue. If such "trained" muscle tissue were translocated within a patient so that it were wrapped around the failing heart, then such translocated muscle tissue could assist, if not take over for, the failing cardiac muscle tissue, thereby allowing the heart to better perform its function of a pump. The idea is that when the stronger skeletal muscle tissue contracts, after it has been wrapped around the heart, it compresses the heart from the outside, thereby augmenting the vigor with which the heart ejects (pumps) blood. Such translocation of skeletal or other strong muscle tissue around the heart is referred to as "cardiac myoplasty".
Cardiac myoplasty offers the advantage of avoiding some of the more common and serious problems associated with cardiac transplant, namely a limited supply of donor hearts, rejection of the donated heart, or infection due to the immunosuppressive agents used to prevent rejection. Advantageously, there is almost always some healthy skeletal or other muscle tissue of the patient that may be translocated and wrapped around the patient's heart. Thus, unlike transplanted hearts (which are in limited supply; are usually only located after diligent searching and long waiting; and, when found, must still be safely transported to a medical facility where the transplant operation can take place), the skeletal or other muscle tissue is with the patient at all times. Further, because the translocated muscle tissue is the patient's own tissue, there is no risk of rejection, as commonly occurs when a heart is transplanted. Using translocated muscle tissue also eliminates the need for lifetime pharmacological therapy with agents designed to prevent rejection, yet which agents have a high incidence of side effects (such as atherosclerosis, altered post-immunocompetence resulting in infection and malignancy). Such agents also tend to be very expensive. Hence, cardiac myoplasty offers a very attractive alternative to cardiac transplant.
In order for cardiac myoplasty to be a viable option for a patient suffering from congestive heart failure, there is a need in the art for a quick and safe method or technique of training the muscle tissue that has been translocated around the heart. Such training of the muscle tissue involves repetitive stimulation of the muscle tissue with a stimulation device, e.g., a pulse generator.
There are two types of pulse generators currently in use to provide the dual-chamber stimulation: a demand-type "DDD" pacemaker, and a dedicated cardiac myostimulator. A myostimulator system typically comprises a first intramuscular lead near the nerve branches of the translocated muscle tissue, a second intramuscular lead placed distal from the first to act as the anode, and a third lead for sensing native depolarizations of the heart.
The present invention includes a pulse generator, means for sensing the native heartbeat, and means for simultaneously delivering an output pulse of the pacemaker to a desired stimulation location. More specifically, the present invention utilizes a single-chamber bipolar pacemaker operating in a triggered mode (e.g., the VVT mode). In the VVT mode, stimulation pulses are generated or "triggered" upon the electrical sensing of depolarization signals (R-waves) in the ventricle. In the prior art, the triggered stimulation was used exclusively for diagnostic purposes (e.g., to verify proper sensing by marking sensed cardiac signals with a pulse) and generally not used for long-term pacing since the triggered pulse accelerated battery depletion. The present invention advantageously redirects the triggered stimulation pulse to the translocated muscle tissue to contract in synchrony with the natural cardiac tissue around which the translocated tissue is wrapped. Advantageously, the pulse generator is an off-the-shelf single-chamber pacemaker, thereby allowing it to be smaller and less cqstly than either a dual-chamber device or a custom myoplasty stimulator. Furthermore, the single-chamber pacemaker may be easily modified to programmably generate either a single pulse or a train of closely-spaced pulses.
A stimulation system made in accordance with the present invention is designed for a patient who has received cardiac myoplasty (translocated muscle tissue around the heart). Such system may be characterized as including: (1) a single-chamber implantable pulse generator having means for sensing ventricular depolarization at a ventricular tissue location and means for generating a stimulation pulse in response thereto; and (2) delivery means for delivering a stimulation pulse generated by the stimulation device to the translocated muscle tissue. With such system, the translocated muscle tissue placed around the patient's heart may be stimulated to contract at the same time that the ventricular cardiac tissue is sensed to depolarize.
A method of stimulating a heart that has undergone cardiac myoplasty in accordance with the present invention uses a cardiac pacemaker operating in a single-chamber mode. Such method includes the steps of: (a) implanting a first electrode so as to contact ventricular tissue; (b) implanting a second electrode so as to contact translocated muscle tissue placed around the heart by the cardiac myoplasty; (c) electrically connecting both the first and second electrodes to an output terminal of a single-chamber pacemaker; and (d) operating the pacemaker in a triggered single-chamber mode of operation, so that depolarization of the ventricular tissue is sensed by the pacemaker, and so that a stimulation pulse generated by the pacemaker is delivered to the translocated muscle tissue. The triggered single-chamber mode of operation advantageously generates a stimulation pulse upon sensing a cardiac depolarization. Hence, a stimulation pulse is delivered to the translocated muscle tissue in synchrony with the sensed depolarization of the ventricular tissue, i.e., in synchrony with the contraction of the ventricles of the heart.
Thus it can be seen that the present invention advantageously provides various techniques, components and/or aids that may be used with a patient having undergone cardiac myoplasty. Each of these techniques, components and/or aids may be considered as a different embodiment of the invention. Such embodiments include, but are not necessarily limited to: (1) a stimulation system, including a stimulation device and delivery means (such as a bifurcated lead adapter with leads, or a bifurcated lead) that delivers a stimulation pulse to transplanted muscle tissue in synchrony with the heart's natural rhythm; (2) a bifurcated lead adapter that allows two stimulation leads to be connected to the single output connector of a single-chamber pacemaker; (3) a bifurcated lead that allows two widely spaced tissue stimulation locations, one of which may be an endocardial or epicardial location and the other of which may be translocated muscle tissue, to be electrically coupled to the single output connector of a single-chamber pacemaker; or (4) a method of stimulating a heart having undergone cardiac myoplasty.
It is still an additional feature of the invention to provide a method of stimulating a patient's heart that has undergone cardiac myoplasty.
FIG. 3 illustrates a pulse generator coupled to a Latissimus dorsi muscle for training the muscle in anticipation of translocating the muscle in a cardiomyoplasty procedure;
In FIG. 2, a dedicated myostimulator system is shown as is known in the art. Such system includes a myostimulator device 106 in contact with the heart 104 of the patient 100, where the heart 104 has had translocated muscle tissue 103 wrapped therearound. A first intramuscular lead 108 is used cathodically (-) and placed near the nerve branches 110 of the translocated Latissimus dorsi tissue 103. A second intramuscular lead 112 is used anodically (+) and is placed distally in the muscle 103. A third lead 114 is used to sense native depolarization of the heart 104. Such placement of the leads 108, 112, and 114 is further illustrated in FIG. 3. Upon detection of a native depolarization through the sensing lead 114, the myostimulator device 106 initiates a synchronization delay, and then stimulates the translocated muscle 103 with a burst of stimulation pulses delivered through the leads 108 and 112.
As has been indicated, the present invention relates to a system and method of stimulating a heart that has undergone cardiac myoplasty. More specifically, the invention provides a system and method for stimulating translocated muscle tissue wrapped around the heart using a pacemaker that operates in a single-chamber triggered mode, e.g., the VVT mode.
The design, operation and use of implantable pacemakers is well known in the art, and will not be repeated herein. See, e.g., Furman et al., A Practice of Cardiac Pacing, Futura Publishing Co., Inc. Mt. Kisco, N.Y. (1986); U.S. Patent No. 4,712,555, issued to Thornander et al. (relating to a physiologically responsive pacemaker); and/or U.S. Patent No. 4,940,052, issued to Mann et al. (relating to a microprocessor-controlled pacemaker). The '555 and '052 patents are incorporated herein by reference.
In accordance with the present invention, the triggered mode is advantageously used to assure that translocated muscle tissue (e.g., skeletal tissue, placed around the heart in accordance with cardiac myoplasty) is stimulated in synchrony with the natural contraction of the ventricle. To this end, there is shown in FIG. 4, a system 120 embodying various features of the present invention. Such system 120 includes a bifurcated bipolar lead adapter 122, such as is commercially available from Siemens Pacesetter, Inc., of Sylmar, California, as Model No. 501205. The adapter 122 has a male proximal connector 124 that is electrically connected to the bipolar output connector 126 of a single-chamber pacemaker 128. The adapter 122 further includes distal female connectors 130 and 132. The male proximal ends of standard unipolar pacing leads 134 and 136 are connected to the female connectors 130 and 132, respectively, of the adapter 122. A suitable unipolar pacing lead that may be used for the pacing leads 134 and 136 is the Model 1015M pacing lead (passive fixation) or the Model 1028 T pacing lead (active fixation), both of which are also commercially available from Siemens Pacesetter, Inc.
As shown in FIG. 6, a distal tip electrode 139 of the lead 134 is secured or positioned within the right ventricle of a patient's heart 104, in conventional manner. (Alternately, the distal tip electrode 139 could be secured or positioned on or to epicardial ventricular tissue.) In contrast, a distal tip electrode 141 of the lead 136 is secured to translocated skeletal muscle tissue 103 that has been wrapped around the left ventricle of the heart 104 using cardiac myoplasty techniques.
A first and a second distal female connector 70 and 90 may be provided at the distal ends of the adapter 60. The first distal female connector 70 is constructed using the same techniques and standards as are used in constructing the output connector of a pacemaker. See, e.g., U.S. Patent Nos. 4,764,132 and 4,848,346, incorporated herein by reference. Essentially, this construction includes a first conductive block 72 and a second conductive ring terminal 74. The conductive block 72 has a hole through its center adapted to receive a proximal connector pin 82 of a conventional bipolar or unipolar lead 80. The conductive block 72 and ring terminal 74 are spaced apart a prescribed distance by means of a nonconductive substrate 76. The nonconductive substrate 76 is shaped and formed so as to be compatible with the applicable standard of the pacemaker lead. Thus, the substrate is formed and/or machined so as to have a cavity 78 therein into which the proximal end of a pacemaker lead may be inserted.
Typically, the conductive block 72 has a set screw 73 therein, or equivalent. This set screw provides a means for detachably securing the connector pin 82 of the lead 80 within the connector 70. A set screw may also be used to make secure electrical connection with the ring electrode 81; however, in the preferred embodiment, a canted coil garter spring is used. For a more complete description of canted coil garter springs, see U.S. Patent No. 5,012,807, issued 05/07/91, which patent is assigned to the same assignee as is the present application and is hereby incorporated herein by reference.
Alternately, the lead 40, or the adapter 122 or 60, could be made using a "thin bipolar" configuration as described in U.S. Patent Application No. 07/716,032, filed 6/14/91, assigned to the same assignee as is the present application and incorporated herein by reference. "Thin bipolar," as used in the above-identified patent application, refers to a coaxial bipolar lead wherein individual filars are electrically insulated from each other by a thin polymer insulative coating and then coaxially wound together. The insulative coating may be the polymer materials sold under the trademarks TEFLON and TEFZEL, manufactured by DuPont, which materials have good electrical insulating properties without adding significant bulk. Typically, each conductor is comprised of two filars for redundancy.
The treatment method next involves operating the pacemaker in a VVT mode. This mode causes a stimulus to be released in response to a sensed R-wave. Thus, a native R-wave is detected across the ventricular electrode and the other electrode. In response to sensing the R-wave, the pacemaker releases an output stimulus consistent with the VVT triggered mode of operation, which pulse is applied across the electrodes to stimulate the translocated muscle tissue. Stimulation of the translocated muscle tissue causes it to contract, thereby assisting the overall heart contraction by squeezing the ventricle.
It is further seen that the present invention provides, in one embodiment, a lead adapter for use with a single-chamber pacemaker that allows two otherwise conventional pacing leads to be electrically connected to the single output connector, and hence the single output amplifier of the single-chamber pacemaker. In another embodiment, the invention provides a lead for use with a single-chamber pacemaker that allows the single output amplifier of the pacemaker to be in simultaneous electrical contact with two widely spaced tissue locations.
The invention also extends to a method of stimulating a heart having undergone cardiac myoplasty using a pacemaker, the pacemaker having an output connector with a first and a second terminal, the cardiac myoplasty including translocating muscle tissue from one body location and wrapping it around the outside of the ventricle of the heart, the method comprising the steps of: (a) implanting a first electrode so as to contact ventricular tissue; (b) implanting a second electrode so as to be coupled to the translocated muscle tissue; (c) electrically connecting the first electrode to the first terminal of the output connector of the pacemaker; (d) electrically connecting the second electrode to the second terminal of the output connector of the pacemaker; (e) programming the pacemaker to sense cardiac signals and to provide a stimulus across the first and second electrodes in response thereto so that the translocated muscle contracts in synchrony with sensing the ventricular deplorisation.
Preferably, the translocated muscle tissue includes a neurovascular bundle, wherein: step (a) comprises implanting the first electrode endocardially to contact the ventricular tissue; and step (b) comprises implanting the second electrode so as to contact the neurovascular bundle.
The invention also extends to a method of stimulating a heart having undergone cardiac myoplasty using a single-chamber bipolar pacemaker, the cardiac myoplasty including translocating muscle tissue from one body location, such as skeletal muscle, and wrapping it around the outside of the heart, the method comprising the steps of: (a) implanting a first electrode so as to contact ventricular tissue; (b) implanting a second electrode so as to contact the translocated muscle tissue or a neurovascular bundle leading to the translocated muscle tissue; (c) electrically connecting both the first and second electrodes to a single-chamber bipolar output connector of the pacemaker so that ventricular activity sensed through the first electrode may be sensed by the pacemaker, and so that a stimulus generated by the pacemaker is delivered to the translocated muscle tissue; and (d) operating the pacemaker in a specified single-chamber mode of operation, whereby cardiac activity is sensed and stimuli are delivered to both the ventricular tissue and translocated muscle tissue as dictated by the single-chamber mode of operation.
Preferably the specified single-chamber mode of operation comprises a triggered mode of operation wherein a stimulus is generated upon sensing ventricular activity. Preferably, the first electrode is implanted so as to be in contact with the right ventricle of the heart, and wherein the specified single-chamber mode of operation of the pacemaker comprises a VVT mode of operation. Preferably the step of electrically connecting both the first and second electrodes to the output connector of the pacemaker comprises: connecting a bifurcated adapter to the output connector of the pacemaker; and detachably connecting the proximal connector of first and second pacemaker leads to the bifurcated adapter, the first and second electrodes being located at a distal end of the first and second pacemaker leads; the bifurcated adapter having means for electrically connecting both of the pacemaker leads to the output connector of the pacemaker.
A stimulation system for stimulating translocated muscle tissue in a patient having cardiac myoplasty, comprising:
delivery means having a first distal electrode for contact with a first tissue location and a second distal electrode for contact with a second, widely-spaced, tissue location, the first and second distal electrode in electrical contact with the first and second output terminals, respectively, for sensing cardiac signals at the first tissue location and delivering the stimulus generated by the pulse generator to the second, widely-spaced, tissue location, the first tissue location including translocated muscle tissue, the second, widely-spaced, tissue location including muscle ventricular tissue;
whereby the delivery means enables the implantable pulse generator to sensed cardiac signals originating in the ventricles and to synchronously triggers the translocated muscle tissue, at the widely-spaced tissue location, to contract.
The stimulation system, as set forth in Claim 1, wherein the delivery means includes means for electrically connecting the first output terminal to the translocated muscle tissue and for electrically connecting the second output terminal to the ventricular tissue.
The stimulation system, as set forth in Claim 2, wherein the implantable pulse generator comprises means for operating in a single-chamber mode of operation.
The stimulation system, as set forth in Claim 1, wherein the bipolar output channel comprises:
a connector top having a receptacle for receiving the delivery means, the receptacle having the first and second output terminals axially disposed therein and electrically isolated therebetween, so that the first and second output terminals are in-line.
The stimulation system, as set forth in Claim 4, wherein the delivery means comprises:
The stimulation system, as set forth in Claim 5, wherein the first and second stimulation leads comprise first and second unipolar leads, respectively.
The stimulation system, as set forth in Claim 5, wherein the Y-shaped lead adapter comprises a bifurcated lead adapter.
The stimulation system, as set forth in Claim 5, wherein the implantable pulse generator comprises a single-chamber pulse generator.
The stimulation system, as set forth in Claim 1, further comprising:
The stimulation system, as set forth in Claim 5, wherein the sensing means includes means for sensing cardiac signals between the between the distal electrode of the first stimulation lead in contact the translocated muscle tissue and the distal electrode of the second stimulation lead in contact the ventricular tissue.
The stimulation system, as set forth in Claim 11, wherein the means for generating a stimulus includes means for generating the stimulus between the distal electrode of the first stimulation lead in contact the translocated muscle tissue and the distal electrode of the second stimulation lead in contact the ventricular tissue.
The stimulation system, as set forth in Claim 1, wherein:
the first and second output terminals comprise a cathode terminal and an anode terminal; and
the delivery means includes means for electrically connecting the cathode terminal to the translocated muscle tissue and for electrically connecting the anode and cathode terminals to the ventricular tissue, such that a sensed cardiac signal sensed will trigger a stimulus simultaneously to the translocated muscle tissue and to the ventricular tissue.
A stimulation system for stimulating translocated muscle tissue in a patient having cardiac myoplasty, comprising: an implantable pulse generator having means for sensing cardiac signals and pulse generating means for synchronously triggering a stimulus in response thereto, the implantable pulse generator having a bipolar output channel, the bipolar output channel having first and second output terminals, the sensing means being coupled to the first and second output terminals so that cardiac signals are sensed therebetween, the pulse generating means being coupled to the first and second output terminals so that the first and second output terminals act as a cathode and an anode terminal, respectively; and delivery means having a ring and a first tip electrode for contact with ventricular tissue and a second tip electrode for contact with the translocated muscle tissue, the first and second tip electrode in electrical contact with the first output terminal, the ring electrode in electrical contact with the second output terminal; whereby the delivery means enables the implantable pulse generator to sense cardiac signals and to trigger an electrical stimulus simultaneously to the translocated muscle tissue and to the ventricular tissue.
The stimulation system, as set forth in Claim 16, wherein the delivery means comprises: a first stimulation lead having a proximal pin and a proximal ring terminal electrically connected to the first tip and the ring electrode; a second stimulation lead having a proximal pin terminal electrically connected to the second tip electrode; and a Y-shaped lead adapter having a proximal male connector and first and second distal female connectors, the proximal male connector including a pin and a ring terminal, the first and second female connectors dimensioned to receive the first and second stimulation leads, respectively, the first female connector having means for electrically connecting the proximal pin and the proximal ring terminals of the first stimulation lead to the pin and ring terminals of the adapter, the second female connector having means for electrically connecting the proximal pin terminal of the second stimulation lead to the pin terminal of the adapter, so that when the proximal male connector is inserted into the bipolar output channel of the implantable pulse generator, and when the first and second leads are inserted into the first and second female connectors, respectively, the tip electrodes of the first and second leads are electrically connected to the cathode terminal and the ring electrode is connected to the anode terminal.
The stimulation system, as set forth in Claim 17, wherein the first and second stimulation leads comprise a bipolar and unipolar lead, respectively.
The stimulation system, as set forth in Claim 17, wherein the implantable pulse generator further comprises: a case electrode; and switching means for programmably selecting one of the case electrode or the ring electrode of the first stimulation lead to act as a reference electrode for the sensing means; whereby the sensing means selectively senses cardiac signals in one of a unipolar fashion between the first tip electrode and the case electrode or in a bipolar fashion between the first tip and ring electrodes.
The stimulation system as set forth in Claim 16, wherein the delivery means comprises: a Y-shaped lead having a male connector at a proximal end dimensioned to fit within the bipolar output channel of the implantable pulse generator, the male connector including a pin terminal and a ring terminal, the lead further having first and second branches, the first branch having a distal tip electrode and a ring electrode electrically connected to the pin and ring terminals, the second branch having a distal tip electrode electrically connected to the pin terminal, the tip electrodes of the first and second branches for contacting the ventricular tissue and the translocated muscle tissue, respectively, so that when the male connector is inserted into the bipolar output channel connector of the implantable pulse generator, the tip electrodes of the first and second branches are electrically connected to the cathode terminal, and the ring electrode is connected to the anode terminal.
The stimulation system, as set forth in any preceding Claim, wherein the stimulus generated by the pulse generating means comprises one of a single pulse or a burst of closely-spaced pulses.
A stimulation system for controlling a patient's heart having translocated muscle tissue wrapped therearound by cardiac myoplasty, comprising: stimulation/sensing means, having an input/output connector having a cathodic and an anodic terminal, for sensing the depolarisation of the ventricle and for generating a stimulus in response thereto; first conducting means having a distal end connected for contact with the ventricle of a heart and a proximal end electrically connected to the anodic terminal; and second conducting means having a distal end for contact with the translocated muscle tissue and a proximal end electrically connected to the cathodic terminal, the translocated tissue being widely-spaced from the ventricular tissue; whereby cardiac signals are sensed and a stimulus is delivered between two widely-spaced tissue sites.
The stimulation system as set forth in Claim 22, wherein the first and second conducting means comprise: a first and second pacing lead; and an adapter configured to connect the first and second pacing leads to the anodic and the cathodic terminals, respectively, of the input/output connector of the stimulation/sensing means.
The stimulation system, as set forth in Claim 23 wherein the first and second pacing leads comprise unipolar pacing leads.
A stimulation system for controlling a patient's heart having translocated muscle tissue wrapped therearound by cardiac myoplasty, comprising: stimulation/sensing means, having an input/output connector having a cathodic and an anodic terminal, for sensing the depolarisation of the ventricle and for generating a stimulus in response thereto; and a delivery means having a first tip electrode for contact with translocated muscle tissue and a second tip electrode for contact with ventricular tissue, the first and second tip electrode being electrically connected to the cathode, the delivery means further having a distal ring electrode for contact with the ventricular tissue and electrically connected to the anode; whereby the delivery means enables the implantable pulse generator to generate a stimulus simultaneously to the translocated muscle tissue and to the ventricular tissue in response to a sensed cardiac signal.
A stimulation system for stimulating translocated muscle tissue in a patient having cardiac myoplasty, comprising: an implantable pulse generator having means for sensing cardiac signals and pulse generating means for synchronously triggering a stimulus in response thereto, the implantable pulse generator having a bipolar output channel with first and second output terminals, the implantable pulse generator further having a case electrode, the pulse generating means being coupled to the first output terminal and one of the case electrode or the second output terminal so that the first output terminal acts as a cathode, the sensing means being coupled to the second output terminal and one of the case electrode or the first output terminal; and delivery means having a first distal electrode for contact with the first tissue location and a second distal electrode for contact with a second, widely-spaced, tissue location, the first tissue location including translocated muscle tissue, the second, widely-spaced, tissue location including ventricular tissue, the first and second distal electrode in electrical contact with the first and second output terminals, respectively; whereby the delivery means enables the implantable pulse generator to sense cardiac signals at a first tissue location and provide electrical stimulus to a second, widely-spaced, tissue location.
EP93309258A 1992-11-20 1993-11-19 System and method for stimulating a heart having undergone cardiac myoplasty using a single-chamber pacemaker. Withdrawn EP0599567A3 (en)
US979502 1992-11-20
US07/979,502 US5328442A (en) 1992-11-20 1992-11-20 System and method for stimulating a heart having undergone cardiac myoplasty using a single-chamber pacemaker
EP0599567A2 true EP0599567A2 (en) 1994-06-01
EP0599567A3 EP0599567A3 (en) 1996-08-28
EP93309258A Withdrawn EP0599567A3 (en) 1992-11-20 1993-11-19 System and method for stimulating a heart having undergone cardiac myoplasty using a single-chamber pacemaker.
AU (1) AU662701B2 (en)
1992-11-20 US US07/979,502 patent/US5328442A/en not_active Expired - Fee Related
1993-11-19 EP EP93309258A patent/EP0599567A3/en not_active Withdrawn
1993-11-22 JP JP31607593A patent/JPH06197994A/en active Pending
1993-11-22 AU AU51851/93A patent/AU662701B2/en not_active Expired - Fee Related
AU5185193A (en) 1994-06-02
US5328442A (en) 1994-07-12
JPH06197994A (en) 1994-07-19
EP0599567A3 (en) 1996-08-28
AU662701B2 (en) 1995-09-07