CA2460033A1 - Methods and apparatus for reducing the likelihood of atrial fibrillation - Google Patents
Methods and apparatus for reducing the likelihood of atrial fibrillation Download PDFInfo
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- CA2460033A1 CA2460033A1 CA002460033A CA2460033A CA2460033A1 CA 2460033 A1 CA2460033 A1 CA 2460033A1 CA 002460033 A CA002460033 A CA 002460033A CA 2460033 A CA2460033 A CA 2460033A CA 2460033 A1 CA2460033 A1 CA 2460033A1
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N1/00—Electrotherapy; Circuits therefor
- A61N1/18—Applying electric currents by contact electrodes
- A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
- A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
- A61N1/362—Heart stimulators
- A61N1/3621—Heart stimulators for treating or preventing abnormally high heart rate
- A61N1/3622—Heart stimulators for treating or preventing abnormally high heart rate comprising two or more electrodes co-operating with different heart regions
Abstract
Methods and apparatus for reducing the incidence of atrial fibrillation includes selecting a desired ventricular rate, pacing the ventricle of the heart at the desired ventricular rate, and pacing the atrium of the heart at twice the desired ventricular rate while the desired ventricular rate is les s than a preferred rate. Some methods of the present invention include pacing the atrium of the heart at the desired ventricular rate while the desired ventricular rate is greater than the preferred rate. Other methods of the present invention include pacing the atrium of the heart at a predetermined/preferred atrial rate while the desired ventricular rate is greater than the preferred rate.
Description
METHODS AND APPARATUS FOR REDUCING THE
LIKELIHOOD OF ATRIAL FIBRILLATION
The present invention relates generally to cardiac pacemakers. More particularly, the present invention relates to cardiac pacemakers for treating atrial fibrillation.
BackEround of the Invention An arrhythmia is a heart rhythm disorder which interferes with the life sustaining blood circulation activities of the heart. Examples of arrhythmias include ventricular fibrillation and atrial fibrillation. Ventricular fibrillation affects the lower chambers of the heart (the ventricles) and atrial fibrillation affects the upper chambers of the heart (the atria). Ventricular fibrillation is a rapid and disorganized firing of muscle fibers within the ventricular myocardium. During ventricular fibrillation, the ventricles do not contract in an organized manner, no blood is pumped, and blood pressure falls to zero.
Patient death may occur within 4 minutes from the onset of ventricular fibrillation.
Companies such as Medtronic, Inc., have developed implantable defibrillators which may be used to successfully treat ventricular fibrillation by delivering a defibrillating shock to the heart when fibrillation is detected.
Atrial fibrillation occurs more frequently than ventricular fibrillation. It has been estimated that atrial fibrillation affects more than 5 million people worldwide. As people age, their chances of developing atrial fibrillation increase dramatically. In fact, approximately 70% of all people with atrial fibrillation are over 65 years of age. Although atrial fibrillation occurs with great frequency, successful therapies for atrial fibrillation have been difficult to identify.
The symptoms of atrial fibrillation may include shortness of breath, loss of the ability to exercise, chest pain, rapid heart beating, light headedness, and loss of consciousness. When atrial fibrillation occurs, the upper chambers of the heart (the atria) rapidly quiver instead of contracting in an organized manner. The atria of the heart may beat/quiver at a rate of between 350 and 600 times per minute during an episode of atrial fibrillation.
Because the pumping function of the upper chambers does not work properly during atrial fibrillation, blood is not completely emptied from the heart's chambers, causing it to stagnate in the upper chambers of the heart. Over time, clots may form in this stagnant blood. Occasionally, clots may break free and enter the blood stream.
When one of these blood clots lodges in the blood vessels of the brain, a stroke may result. It has been estimated that atrial fibrillation is responsible for over 70,000 strokes each year.
Because treating atrial fibrillation is an important way to prevent strokes from occurring, the American Heart Association has called for aggressive treatment of atrial fibrillation.
Summary of the Invention The present invention relates generally to cardiac pacemakers. More particularly, the present invention relates to cardiac pacemakers for treating atrial fibrillation. The structures and methods in accordance with the present invention may be utilized to reduce the likelihood of atrial fibrillation in a heart. One such method comprises the steps of selecting a desired ventricular rate and pacing the ventricle of the heart at this desired ventricular rate.
In certain implementations, the atrium of the heart is paced at twice the desired ventricular rate while the desired ventricular rate is less than a preferred rate. In these advantageous implementations, the atrium of the heart is paced at the desired ventricular rate while the desired ventricular rate is greater than the preferred rate.
The preferred rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient.
In other implementations, the atrium of the heart is paced at an advantageous atrial rate while the desired ventricular rate is greater than the preferred rate.
While the desired ventricular rate is less than the preferred rate, the atrium of the heart may be paced at twice the desired ventricular rate.
In one aspect of the present invention, an atrial pulse is delivered synchronously with each ventricle pulse. In another aspect of the present invention, a ventricular pulse is delivered substantially synchronous with each atrial pulse while the desired ventricular rate is greater than the preferred rate. While the desired ventricular rate is less than the preferred rate, a ventricle pulse may be advantageously delivered synchronously with one out of two atrial pulses. The synchronous arrangement allows an offset between atrial and ventricular pulses.
In certain implementations, the step of selecting the desired ventricular rate may include the steps of sensing spontaneous ventricular signals, and determining a desired ventricular rate in response to the sensed ventricle signals. Methods in accordance with the present invention may include the step of severing a conductive path between the atrium and the ventricle as one of many preferred surgical procedures in implementing one aspect of the present invention. The step of severing the conductive path between the atrium and the ventricle may comprise, for example, the step of ablating an A-V node of the heart.
A pacing system in accordance with the present invention may include a pacemaker having a controller. The controller may comprise, for example, a microprocessor. The controller may direct a ventricular pulse generator of the pacemaker to provide pacing pulses to a ventricle via one or more leads coupled to one or more ventricular electrodes. The controller may also direct an atrial pulse generator to provide pacing pulses to an atrium via one or more leads coupled to one or more atrial electrodes.
The atrial pulse generator and the ventricular pulse generator may each include one or more capacitors, and a switching circuit capable of charging the capacitors) by coupling the capacitors) to an energy source and discharging the capacitors) through the electrodes.
A pacemaker in accordance with the present invention may also include a signal processor for sensing and processing spontaneous signals from heart.
Spontaneous signals from the heart may be used in determining a desired ventricular rate. In some implementations of the present invention, the signal processor may include one or more amplifiers, and one or more filters. Further rate responses may be established using methods and structures disclosed in U.S. Patent No. 5,052,388 to Sivula which is incorporated herein in its entirety by reference.
A pacemaker in accordance with the present invention may further include a memory. The memory may be used to store operating instructions for the controller. The memory may also be used to store values in accordance with the present invention.
Examples of values that may be stored include a preferred rate and a desired ventricular rate and/or a desired atrial rate. The pacemaker may also include a telemetry antenna.
The telemetry antenna may be used in conjunction with the controller to load instructions and values into the memory.
Description of the Drawings Figure 1 is a cross-sectional view of a heart having ventricles and atria.
Figure 2 is a diagrammatic view of a pacing system in accordance with the present invention.
Figure 3 is a flow diagram illustrating a method of pacing a heart in accordance with the present invention.
Figure 4 is a simplified timing diagram illustrating a sequence of atrial pulses and ventricular pulses which may be produced in accordance with an exemplary method of the present invention.
Figure 5 is a diagrammatic representation of a sequence of atrial pulses and ventricular pulses which may be produced in accordance with an exemplary method of the present invention.
Figure 6 is a diagrammatic representation of a sequence of atrial pulses and ventricular pulses which may be produced in accordance with an exemplary method of the present invention.
Figure 7 is a block diagram of a pacing system in accordance with an exemplary embodiment of the present invention.
Figure 8 is a flow diagram illustrating a method of pacing a heart in accordance with the present invention.
Detailed Descriution of the Preferred Embodiment The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Examples of constructions, materials, dimensions, and manufacturing processes are provided for selected elements. All other elements employ that which is known to those of skill in the field of the invention. Those skilled in the art will recognize that many of the examples provided have suitable alternatives that can be utilized.
Figure 1 is a cross-sectional view of a heart 102 having ventricles 108 and 120. In Figure 1, it may be appreciated that heart 102 includes a conductive path 128 extending between auricle 130 and ventricles 104. In heart 102, conductive path 128 includes an atrioventricular (AV) node 130, a bundle of His 132, a right bundle branch 134, and a left bundle branch 136.
Heart 102 also includes a sinoatrial (SA) node 138. In a healthy heart, the SA
node 5 acts as a natural pacemaker controlling the heart rate. At appropriate times, an electrical impulse arising from the SA node is transmitted to the right and left atrial chambers. This impulse causes muscle tissue of the atria to depolarize and contract which results in a P-wave on the electrocardiogram. Impulses propagated from the SA node travel to and through the atrioventricular (AV) node. The impulse from the AV node is transmitted through the bundle of His, the right bundle branch, the left bundle branches, and a plurality of Purkinje fibers that cover most of the endocardial surface of the ventricles.
The ventricular muscle tissue depolarizes, then contracts. This forces blood held in the ventricles through the arteries and to various body locations. This action is repeated in a rhythmic cycle in which the atrial and ventricular chambers alternately contract and pump, then relax and fill.
Figure 2 is a diagrammatic view of a pacing system 140 in accordance with the present invention. Pacing system 140 includes a pacemaker 142 that is coupled to heart 102 of Figure 1 by a pluarality of leads 144 and electrodes 146. Pacemaker 142 may be used to treat a heart in which the natural pacing system has ceased performing properly.
Pacemaker 142 may have a single electrode operation in which pacing current flows between an electrode 146 and a housing of pacemaker 142. Pacemaker 142 may also have a dual electrode operation in which pacing current flows between two or more electrodes.
Some methods in accordance with the present invention may include the step of severing the conductive path between atria 122 and ventricles 104. In some methods, the step of severing the conductive path may include the step of ablating the AV
node of a heart. The step of ablating the AV node may be accomplished, for example, using a catheter including an ablation electrode coupled to a source of radio frequency energy. By comparing Figure 1 and Figure 2, it may be appreciated that the AV node of heart 102 has been ablated in the embodiment of Figure 2.
Figure 3 is a flow diagram 148 illustrating a method of pacing a heart in accordance with the present invention. The method of Figure 3 may be used, for example, in conjunction with pacing system 140 of Figure 2. At block 150A of flow diagram 148 a preferred rate is selected and stored. In the method of Figure 3, the preferred rate is used to make decisions relating to the pacing of the heart of a patient. The preferred rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient. The preferred rate may be stored, for example, in a memory of pacemaker 142 of pacing system 140 of Figure 2.
At block 1 SOB of flow diagram 148, a desired ventricular rate is selected. In some methods in accordance with the present invention, the step of selecting the desired ventricular rate may include the steps of sensing spontaneous ventricular signals, and determining a desired ventricular rate in response to the sensed ventricle signals.
At block 150C of flow diagram 148, the ventricle is paced at the desired ventricular rate. Pacing pulses may be delivered to the ventricle, for example, via one or more leads coupled to one or more electrodes. A pulse generator in accordance with the present invention may include one or more capacitors, and a switching circuit capable of charging the capacitors) by coupling the capacitors) to an energy source and discharging the capacitors) through the electrodes.
At block 1 SOD, a determination is made as to whether or not the desired ventricular rate is greater than the preferred rate. In the method of Figure 3, the atrium will be paced at the desired ventricular rate (block 1 SOE) if the desired ventricular rate is greater than the preferred rate. Also in the method of Figure 3, the atrium will be paced at twice the desired ventricular rate (block 1 SOF) if the desired ventricular rate is less than the preferred rate.
Figure 4 is a simplified timing diagram illustrating an sequence of atrial pulses 152 and ventricular pulses 154 which may be produced in accordance with an exemplary method of the present invention. In the embodiment of Figure 4, ventricular pulses 154 are being delivered to at least one ventricle of a heart at a desired ventricular rate. A
desired ventricular period 156 associated with the desired ventricular rate is illustrated in Figure 4.
In the embodiment of Figure 4, atrial pulses 152 are being delivered to the atria of the heart at a desired atrial rate. A desired atrial period 158 associated with the desired atrial rate is illustrated in Figure 4. In Figure 4, atrial period 158 is half the ventricular period 156. Thus, in the embodiment of Figure 4, the atria are being paced at twice the desired ventricular rate. In Figure 4 it may be appreciated that the ratio of the atrial rate to the ventricular rate (A-V ratio) may be described as being 2:1.
Figure 5 is a diagrammatic representation of a sequence of atrial pulses 252 and ventricular pulses 254 which may be produced in accordance with an exemplary method of the present invention. In the embodiment of Figure 5, the atrium and the ventricle are both being paced at a desired ventricular rate. Thus, in Figure 5, the A-V
ratio is 1:1. In the embodiment of Figure 5, an atrial pulse is delivered approximately substantially synchronous with each ventricle pulse.
Referring again, briefly, to Figure 4 it may be appreciated that in the method of Figure 4, a ventricle pulse is delivered synchronously with one out of two atrial pulses.
Referring again to Figure 5, an atrial period 258 and a ventricular period 256 are illustrated in Figure 5. In Figure 5 it may be appreciated that atrial period 258 has the same length as ventricular period 256.
In some methods in accordance with the present invention, the atrium is paced at twice the desired ventricular rate (2:1 A-V ratio) while the desired ventricular rate is less than a preferred rate. Also in some methods in accordance with the present invention, the atrium is paced at the desired ventricular rate (1:1 A-V ratio) while the desired ventricular rate is greater than the preferred rate. In some methods, in accordance with the present invention, there is a transition period during which the atrial rate transitions from a 2:1 A-V ratio to a 1:1 A-V ratio. In these methods there may also be a transition period during which the atrial rate transitions from a 1:1 A-V ratio to a 2:1 A-V ratio.
During these transition periods, the atrial period may be incrementally changed until the desired A-V
ratio is reached.
Figure 6 is a diagrammatic representation of a sequence of atrial pulses 352 and ventricular pulses 354 which may be produced in accordance with an exemplary method of the present invention. Figure 6 includes a proximal region 364, a distal region 366, and a transition region 368 disposed between proximal region 364 and distal region 366. In the embodiment of Figure 6, atrial pulses 352 and ventricular pulses 370 of proximal region 364 exhibit an A-V ratio of about 2:1. Also in Figure 6, atrial pulses 352 and ventricular pulses 354 of distal region 366 exhibit an A-V ratio of 1:1.
In Figure 6 it may be appreciated that the atrium and the ventricle are being synchronously paced in proximal region 364 and distal region 366. In Figure 6 it may also be appreciated that the atrium and the ventricle are being asynchronously paced in transition region 368. In the embodiment of Figure 6, the atrial pulses 352 disposed in transitional region 368 are separated by transitional pacing periods 374.
Methods in accordance with the present invention are possible in which these transitional pacing periods 374 are incrementally changed until a desired A-V ratio is obtained.
Methods in accordance with the present invention are possible in which the atrial rate is slowly incremented until A-V synchrony is reached.
Figure 7 is a block diagram of a pacing system 340 in accordance with an exemplary embodiment of the present invention. As shown in Figure 7, pacing system 340 comprises a pacemaker 342 including a controller 376. Controller 376 may comprise, for example, a microprocessor.
A ventricular pulse (VP) generator 378 of pacemaker 342 provides pacing pulses, generated under the control of controller 376, for delivery through a ventricle pulse VP-lead 380 to one or more ventricular electrodes 346. In the embodiment of Figure 7, a ventricular electrode 346 is shown disposed in a right ventricle 320 of a heart 302. It is to be appreciated that methods and apparatus in accordance with the present invention may be used with multiple chamber pacing. Thus, in some applications, one or more ventricular electrodes may also be located in or near a left ventricle 308 of heart 302. An atrial pulse generator 386 of pacemaker 342 provides atrial pulses, also generated under the control of controller 376, for delivery through an atrial pulse AP-lead 388 to one or more atrial electrodes 384. Atrial pulse generator 386 and ventricular pulse generator 378 may each include one or more capacitors, and a switching circuit capable of charging the capacitors) by coupling the capacitors) to an energy source and discharging the capacitors) through the electrodes.
Pacemaker 342 also includes a signal processor 390 which may be used to sense and process spontaneous signals from heart 302. For example, signals may be sensed from right atrium 326 via atrial electrode 384. By way of a second example, signals from right ventricle 320 may be sensed via ventricular electrode 346. A method in accordance with the present invention may include the steps of sensing spontaneous signals from heart 302 and determining a desired ventricular rate in response to the sensed ventricle signals.
Signal processor 390 may comprise, for example, one or more amplifiers, and one or more filters.
Pacemaker 342 also includes a memory 394. Memory 394 may be used to store operating instructions for controller 376. Memory 394 may also be used to store values in accordance with the present invention. Examples of values which may be stored include a preferred rate and a desired ventricular rate. Pacemaker 342 also includes a telemetry antenna 396. Telemetry antenna may be used, for example, to load instructions and values into memory 394 via controller 376.
Figure 8 is a flow diagram 548 illustrating a method of pacing a heart in accordance with the present invention. The method of Figure 8 may be used, for example, 1 S in conjunction with pacing system 540 of Figure 7. At block SSOA of flow diagram 548 an advantageous rate is selected and stored. The advantageous rate may be stored, for example, in memory 594 of pacemaker 542 of pacing system 540 of Figure 7.
At block SSOB of flow diagram 548 a preferred rate is selected and stored. In a useful embodiment of the present method, the preferred rate may be chosen from a range of between about 60 beats per minute and about 100 beats per minute. The preferred rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient. In some embodiments, the preferred rate may be, for example, about 80 beats per minute. In the method of Figure 8, the preferred rate is used to make decisions relating to the pacing of the heart of a patient.
At block SSOC of flow diagram 548, a desired ventricular rate is selected. In some methods in accordance with the present invention, the step of selecting the desired ventricular rate may include the steps of sensing spontaneous ventricular signals, and determining a desired ventricular rate in response to the sensed ventricle signals.
At block SSOD of flow diagram 548, the ventricle is paced at the desired ventricular rate. Pacing pulses may be delivered to the ventricle, for example, via one or more leads coupled to one or more electrodes. The method of Figure 8 also includes the step of pacing the atrium, however, the atrial rate is selected based upon a determination made at block 550E.
At block 550E, a determination is made as to whether or not the desired ventricular rate is greater than the preferred rate. In the method of Figure 8, the atrium will be paced 5 at the advantageous pacing rate (block 550F) if the desired ventricular rate is greater than the preferred rate. Also in the method of Figure 8, the atrium will be paced at twice the desired ventricular rate (block 550G) if the desired ventricular rate is less than the preferred rate.
In a preferred embodiment, the advantageous rate is selected to be fast enough to 10 reduce the likelihood that atrial fibrillation will occur. The advantageous rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient. In a useful embodiment of the present method, the advantageous rate may be chosen from a range of between about 120 beats per minute and about 180 beats per minute. In some embodiments, the preferred rate may be, for example, about 160 beats per minute.
Several forms of invention have been shown and described, and other forms will now be apparent to those skilled in art. It will be understood that embodiments shown in drawings and described above are merely for illustrative purposes, and are not intended to limit the scope of invention defined claims which follow.
LIKELIHOOD OF ATRIAL FIBRILLATION
The present invention relates generally to cardiac pacemakers. More particularly, the present invention relates to cardiac pacemakers for treating atrial fibrillation.
BackEround of the Invention An arrhythmia is a heart rhythm disorder which interferes with the life sustaining blood circulation activities of the heart. Examples of arrhythmias include ventricular fibrillation and atrial fibrillation. Ventricular fibrillation affects the lower chambers of the heart (the ventricles) and atrial fibrillation affects the upper chambers of the heart (the atria). Ventricular fibrillation is a rapid and disorganized firing of muscle fibers within the ventricular myocardium. During ventricular fibrillation, the ventricles do not contract in an organized manner, no blood is pumped, and blood pressure falls to zero.
Patient death may occur within 4 minutes from the onset of ventricular fibrillation.
Companies such as Medtronic, Inc., have developed implantable defibrillators which may be used to successfully treat ventricular fibrillation by delivering a defibrillating shock to the heart when fibrillation is detected.
Atrial fibrillation occurs more frequently than ventricular fibrillation. It has been estimated that atrial fibrillation affects more than 5 million people worldwide. As people age, their chances of developing atrial fibrillation increase dramatically. In fact, approximately 70% of all people with atrial fibrillation are over 65 years of age. Although atrial fibrillation occurs with great frequency, successful therapies for atrial fibrillation have been difficult to identify.
The symptoms of atrial fibrillation may include shortness of breath, loss of the ability to exercise, chest pain, rapid heart beating, light headedness, and loss of consciousness. When atrial fibrillation occurs, the upper chambers of the heart (the atria) rapidly quiver instead of contracting in an organized manner. The atria of the heart may beat/quiver at a rate of between 350 and 600 times per minute during an episode of atrial fibrillation.
Because the pumping function of the upper chambers does not work properly during atrial fibrillation, blood is not completely emptied from the heart's chambers, causing it to stagnate in the upper chambers of the heart. Over time, clots may form in this stagnant blood. Occasionally, clots may break free and enter the blood stream.
When one of these blood clots lodges in the blood vessels of the brain, a stroke may result. It has been estimated that atrial fibrillation is responsible for over 70,000 strokes each year.
Because treating atrial fibrillation is an important way to prevent strokes from occurring, the American Heart Association has called for aggressive treatment of atrial fibrillation.
Summary of the Invention The present invention relates generally to cardiac pacemakers. More particularly, the present invention relates to cardiac pacemakers for treating atrial fibrillation. The structures and methods in accordance with the present invention may be utilized to reduce the likelihood of atrial fibrillation in a heart. One such method comprises the steps of selecting a desired ventricular rate and pacing the ventricle of the heart at this desired ventricular rate.
In certain implementations, the atrium of the heart is paced at twice the desired ventricular rate while the desired ventricular rate is less than a preferred rate. In these advantageous implementations, the atrium of the heart is paced at the desired ventricular rate while the desired ventricular rate is greater than the preferred rate.
The preferred rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient.
In other implementations, the atrium of the heart is paced at an advantageous atrial rate while the desired ventricular rate is greater than the preferred rate.
While the desired ventricular rate is less than the preferred rate, the atrium of the heart may be paced at twice the desired ventricular rate.
In one aspect of the present invention, an atrial pulse is delivered synchronously with each ventricle pulse. In another aspect of the present invention, a ventricular pulse is delivered substantially synchronous with each atrial pulse while the desired ventricular rate is greater than the preferred rate. While the desired ventricular rate is less than the preferred rate, a ventricle pulse may be advantageously delivered synchronously with one out of two atrial pulses. The synchronous arrangement allows an offset between atrial and ventricular pulses.
In certain implementations, the step of selecting the desired ventricular rate may include the steps of sensing spontaneous ventricular signals, and determining a desired ventricular rate in response to the sensed ventricle signals. Methods in accordance with the present invention may include the step of severing a conductive path between the atrium and the ventricle as one of many preferred surgical procedures in implementing one aspect of the present invention. The step of severing the conductive path between the atrium and the ventricle may comprise, for example, the step of ablating an A-V node of the heart.
A pacing system in accordance with the present invention may include a pacemaker having a controller. The controller may comprise, for example, a microprocessor. The controller may direct a ventricular pulse generator of the pacemaker to provide pacing pulses to a ventricle via one or more leads coupled to one or more ventricular electrodes. The controller may also direct an atrial pulse generator to provide pacing pulses to an atrium via one or more leads coupled to one or more atrial electrodes.
The atrial pulse generator and the ventricular pulse generator may each include one or more capacitors, and a switching circuit capable of charging the capacitors) by coupling the capacitors) to an energy source and discharging the capacitors) through the electrodes.
A pacemaker in accordance with the present invention may also include a signal processor for sensing and processing spontaneous signals from heart.
Spontaneous signals from the heart may be used in determining a desired ventricular rate. In some implementations of the present invention, the signal processor may include one or more amplifiers, and one or more filters. Further rate responses may be established using methods and structures disclosed in U.S. Patent No. 5,052,388 to Sivula which is incorporated herein in its entirety by reference.
A pacemaker in accordance with the present invention may further include a memory. The memory may be used to store operating instructions for the controller. The memory may also be used to store values in accordance with the present invention.
Examples of values that may be stored include a preferred rate and a desired ventricular rate and/or a desired atrial rate. The pacemaker may also include a telemetry antenna.
The telemetry antenna may be used in conjunction with the controller to load instructions and values into the memory.
Description of the Drawings Figure 1 is a cross-sectional view of a heart having ventricles and atria.
Figure 2 is a diagrammatic view of a pacing system in accordance with the present invention.
Figure 3 is a flow diagram illustrating a method of pacing a heart in accordance with the present invention.
Figure 4 is a simplified timing diagram illustrating a sequence of atrial pulses and ventricular pulses which may be produced in accordance with an exemplary method of the present invention.
Figure 5 is a diagrammatic representation of a sequence of atrial pulses and ventricular pulses which may be produced in accordance with an exemplary method of the present invention.
Figure 6 is a diagrammatic representation of a sequence of atrial pulses and ventricular pulses which may be produced in accordance with an exemplary method of the present invention.
Figure 7 is a block diagram of a pacing system in accordance with an exemplary embodiment of the present invention.
Figure 8 is a flow diagram illustrating a method of pacing a heart in accordance with the present invention.
Detailed Descriution of the Preferred Embodiment The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Examples of constructions, materials, dimensions, and manufacturing processes are provided for selected elements. All other elements employ that which is known to those of skill in the field of the invention. Those skilled in the art will recognize that many of the examples provided have suitable alternatives that can be utilized.
Figure 1 is a cross-sectional view of a heart 102 having ventricles 108 and 120. In Figure 1, it may be appreciated that heart 102 includes a conductive path 128 extending between auricle 130 and ventricles 104. In heart 102, conductive path 128 includes an atrioventricular (AV) node 130, a bundle of His 132, a right bundle branch 134, and a left bundle branch 136.
Heart 102 also includes a sinoatrial (SA) node 138. In a healthy heart, the SA
node 5 acts as a natural pacemaker controlling the heart rate. At appropriate times, an electrical impulse arising from the SA node is transmitted to the right and left atrial chambers. This impulse causes muscle tissue of the atria to depolarize and contract which results in a P-wave on the electrocardiogram. Impulses propagated from the SA node travel to and through the atrioventricular (AV) node. The impulse from the AV node is transmitted through the bundle of His, the right bundle branch, the left bundle branches, and a plurality of Purkinje fibers that cover most of the endocardial surface of the ventricles.
The ventricular muscle tissue depolarizes, then contracts. This forces blood held in the ventricles through the arteries and to various body locations. This action is repeated in a rhythmic cycle in which the atrial and ventricular chambers alternately contract and pump, then relax and fill.
Figure 2 is a diagrammatic view of a pacing system 140 in accordance with the present invention. Pacing system 140 includes a pacemaker 142 that is coupled to heart 102 of Figure 1 by a pluarality of leads 144 and electrodes 146. Pacemaker 142 may be used to treat a heart in which the natural pacing system has ceased performing properly.
Pacemaker 142 may have a single electrode operation in which pacing current flows between an electrode 146 and a housing of pacemaker 142. Pacemaker 142 may also have a dual electrode operation in which pacing current flows between two or more electrodes.
Some methods in accordance with the present invention may include the step of severing the conductive path between atria 122 and ventricles 104. In some methods, the step of severing the conductive path may include the step of ablating the AV
node of a heart. The step of ablating the AV node may be accomplished, for example, using a catheter including an ablation electrode coupled to a source of radio frequency energy. By comparing Figure 1 and Figure 2, it may be appreciated that the AV node of heart 102 has been ablated in the embodiment of Figure 2.
Figure 3 is a flow diagram 148 illustrating a method of pacing a heart in accordance with the present invention. The method of Figure 3 may be used, for example, in conjunction with pacing system 140 of Figure 2. At block 150A of flow diagram 148 a preferred rate is selected and stored. In the method of Figure 3, the preferred rate is used to make decisions relating to the pacing of the heart of a patient. The preferred rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient. The preferred rate may be stored, for example, in a memory of pacemaker 142 of pacing system 140 of Figure 2.
At block 1 SOB of flow diagram 148, a desired ventricular rate is selected. In some methods in accordance with the present invention, the step of selecting the desired ventricular rate may include the steps of sensing spontaneous ventricular signals, and determining a desired ventricular rate in response to the sensed ventricle signals.
At block 150C of flow diagram 148, the ventricle is paced at the desired ventricular rate. Pacing pulses may be delivered to the ventricle, for example, via one or more leads coupled to one or more electrodes. A pulse generator in accordance with the present invention may include one or more capacitors, and a switching circuit capable of charging the capacitors) by coupling the capacitors) to an energy source and discharging the capacitors) through the electrodes.
At block 1 SOD, a determination is made as to whether or not the desired ventricular rate is greater than the preferred rate. In the method of Figure 3, the atrium will be paced at the desired ventricular rate (block 1 SOE) if the desired ventricular rate is greater than the preferred rate. Also in the method of Figure 3, the atrium will be paced at twice the desired ventricular rate (block 1 SOF) if the desired ventricular rate is less than the preferred rate.
Figure 4 is a simplified timing diagram illustrating an sequence of atrial pulses 152 and ventricular pulses 154 which may be produced in accordance with an exemplary method of the present invention. In the embodiment of Figure 4, ventricular pulses 154 are being delivered to at least one ventricle of a heart at a desired ventricular rate. A
desired ventricular period 156 associated with the desired ventricular rate is illustrated in Figure 4.
In the embodiment of Figure 4, atrial pulses 152 are being delivered to the atria of the heart at a desired atrial rate. A desired atrial period 158 associated with the desired atrial rate is illustrated in Figure 4. In Figure 4, atrial period 158 is half the ventricular period 156. Thus, in the embodiment of Figure 4, the atria are being paced at twice the desired ventricular rate. In Figure 4 it may be appreciated that the ratio of the atrial rate to the ventricular rate (A-V ratio) may be described as being 2:1.
Figure 5 is a diagrammatic representation of a sequence of atrial pulses 252 and ventricular pulses 254 which may be produced in accordance with an exemplary method of the present invention. In the embodiment of Figure 5, the atrium and the ventricle are both being paced at a desired ventricular rate. Thus, in Figure 5, the A-V
ratio is 1:1. In the embodiment of Figure 5, an atrial pulse is delivered approximately substantially synchronous with each ventricle pulse.
Referring again, briefly, to Figure 4 it may be appreciated that in the method of Figure 4, a ventricle pulse is delivered synchronously with one out of two atrial pulses.
Referring again to Figure 5, an atrial period 258 and a ventricular period 256 are illustrated in Figure 5. In Figure 5 it may be appreciated that atrial period 258 has the same length as ventricular period 256.
In some methods in accordance with the present invention, the atrium is paced at twice the desired ventricular rate (2:1 A-V ratio) while the desired ventricular rate is less than a preferred rate. Also in some methods in accordance with the present invention, the atrium is paced at the desired ventricular rate (1:1 A-V ratio) while the desired ventricular rate is greater than the preferred rate. In some methods, in accordance with the present invention, there is a transition period during which the atrial rate transitions from a 2:1 A-V ratio to a 1:1 A-V ratio. In these methods there may also be a transition period during which the atrial rate transitions from a 1:1 A-V ratio to a 2:1 A-V ratio.
During these transition periods, the atrial period may be incrementally changed until the desired A-V
ratio is reached.
Figure 6 is a diagrammatic representation of a sequence of atrial pulses 352 and ventricular pulses 354 which may be produced in accordance with an exemplary method of the present invention. Figure 6 includes a proximal region 364, a distal region 366, and a transition region 368 disposed between proximal region 364 and distal region 366. In the embodiment of Figure 6, atrial pulses 352 and ventricular pulses 370 of proximal region 364 exhibit an A-V ratio of about 2:1. Also in Figure 6, atrial pulses 352 and ventricular pulses 354 of distal region 366 exhibit an A-V ratio of 1:1.
In Figure 6 it may be appreciated that the atrium and the ventricle are being synchronously paced in proximal region 364 and distal region 366. In Figure 6 it may also be appreciated that the atrium and the ventricle are being asynchronously paced in transition region 368. In the embodiment of Figure 6, the atrial pulses 352 disposed in transitional region 368 are separated by transitional pacing periods 374.
Methods in accordance with the present invention are possible in which these transitional pacing periods 374 are incrementally changed until a desired A-V ratio is obtained.
Methods in accordance with the present invention are possible in which the atrial rate is slowly incremented until A-V synchrony is reached.
Figure 7 is a block diagram of a pacing system 340 in accordance with an exemplary embodiment of the present invention. As shown in Figure 7, pacing system 340 comprises a pacemaker 342 including a controller 376. Controller 376 may comprise, for example, a microprocessor.
A ventricular pulse (VP) generator 378 of pacemaker 342 provides pacing pulses, generated under the control of controller 376, for delivery through a ventricle pulse VP-lead 380 to one or more ventricular electrodes 346. In the embodiment of Figure 7, a ventricular electrode 346 is shown disposed in a right ventricle 320 of a heart 302. It is to be appreciated that methods and apparatus in accordance with the present invention may be used with multiple chamber pacing. Thus, in some applications, one or more ventricular electrodes may also be located in or near a left ventricle 308 of heart 302. An atrial pulse generator 386 of pacemaker 342 provides atrial pulses, also generated under the control of controller 376, for delivery through an atrial pulse AP-lead 388 to one or more atrial electrodes 384. Atrial pulse generator 386 and ventricular pulse generator 378 may each include one or more capacitors, and a switching circuit capable of charging the capacitors) by coupling the capacitors) to an energy source and discharging the capacitors) through the electrodes.
Pacemaker 342 also includes a signal processor 390 which may be used to sense and process spontaneous signals from heart 302. For example, signals may be sensed from right atrium 326 via atrial electrode 384. By way of a second example, signals from right ventricle 320 may be sensed via ventricular electrode 346. A method in accordance with the present invention may include the steps of sensing spontaneous signals from heart 302 and determining a desired ventricular rate in response to the sensed ventricle signals.
Signal processor 390 may comprise, for example, one or more amplifiers, and one or more filters.
Pacemaker 342 also includes a memory 394. Memory 394 may be used to store operating instructions for controller 376. Memory 394 may also be used to store values in accordance with the present invention. Examples of values which may be stored include a preferred rate and a desired ventricular rate. Pacemaker 342 also includes a telemetry antenna 396. Telemetry antenna may be used, for example, to load instructions and values into memory 394 via controller 376.
Figure 8 is a flow diagram 548 illustrating a method of pacing a heart in accordance with the present invention. The method of Figure 8 may be used, for example, 1 S in conjunction with pacing system 540 of Figure 7. At block SSOA of flow diagram 548 an advantageous rate is selected and stored. The advantageous rate may be stored, for example, in memory 594 of pacemaker 542 of pacing system 540 of Figure 7.
At block SSOB of flow diagram 548 a preferred rate is selected and stored. In a useful embodiment of the present method, the preferred rate may be chosen from a range of between about 60 beats per minute and about 100 beats per minute. The preferred rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient. In some embodiments, the preferred rate may be, for example, about 80 beats per minute. In the method of Figure 8, the preferred rate is used to make decisions relating to the pacing of the heart of a patient.
At block SSOC of flow diagram 548, a desired ventricular rate is selected. In some methods in accordance with the present invention, the step of selecting the desired ventricular rate may include the steps of sensing spontaneous ventricular signals, and determining a desired ventricular rate in response to the sensed ventricle signals.
At block SSOD of flow diagram 548, the ventricle is paced at the desired ventricular rate. Pacing pulses may be delivered to the ventricle, for example, via one or more leads coupled to one or more electrodes. The method of Figure 8 also includes the step of pacing the atrium, however, the atrial rate is selected based upon a determination made at block 550E.
At block 550E, a determination is made as to whether or not the desired ventricular rate is greater than the preferred rate. In the method of Figure 8, the atrium will be paced 5 at the advantageous pacing rate (block 550F) if the desired ventricular rate is greater than the preferred rate. Also in the method of Figure 8, the atrium will be paced at twice the desired ventricular rate (block 550G) if the desired ventricular rate is less than the preferred rate.
In a preferred embodiment, the advantageous rate is selected to be fast enough to 10 reduce the likelihood that atrial fibrillation will occur. The advantageous rate may be selected to match a particular patient, for example, by taking into account physical characteristics of that patient. In a useful embodiment of the present method, the advantageous rate may be chosen from a range of between about 120 beats per minute and about 180 beats per minute. In some embodiments, the preferred rate may be, for example, about 160 beats per minute.
Several forms of invention have been shown and described, and other forms will now be apparent to those skilled in art. It will be understood that embodiments shown in drawings and described above are merely for illustrative purposes, and are not intended to limit the scope of invention defined claims which follow.
Claims (16)
1. An implantable medical device comprising:
means for selecting a desired ventricular rate;
means for pacing a ventricular of the heart at the desired ventricular rate;
means for pacing an atrium of the heart at twice the desired ventricular rate while the desired ventricular rate is less than a preferred rate; and means for pacing the atrium of the heart at the desired ventricular rate while the desired ventricular rate is greater than the preferred rate.
means for selecting a desired ventricular rate;
means for pacing a ventricular of the heart at the desired ventricular rate;
means for pacing an atrium of the heart at twice the desired ventricular rate while the desired ventricular rate is less than a preferred rate; and means for pacing the atrium of the heart at the desired ventricular rate while the desired ventricular rate is greater than the preferred rate.
2. The device of claim 2 wherein the preferred rate is between about 60 beats per minute and about 100 beats per minute.
3. The device of claim 1 or 2 wherein the preferred rate is about 80 beats per minute.
4. The device of claim 1 or 2 wherein the means for selecting the desired ventricular rate includes means for sensing spontaneous ventricular signals and means for determining a desired ventricular in response to the sensed ventricle signals.
5. The device of claim 1 wherein an atrial pulse is delivered synchronously with each ventricular pulse.
6. The device of claim 1 wherein a ventricle pulse is delivered synchronously with each atrial pulse white the desired ventricular rate is greater than the preferred rate.
7. The device of claim 1 wherein a ventricle pulse is delivered synchronously with one of two atrial pulses while the desired ventricular rate is less than the preferred rate.
8. An implantable medical device implemented fob reducing the likelihood of atrial fibrillation in a heart, the device comprising:
means for selecting an advantageous atrial rate;
means for selecting a desired ventricular rate;
means for pacing the ventricle of the heart at the desired ventricular rate;
means for pacing the atrium of the heart at twice the desired ventricular rate while the desired ventricular rate is lest than the preferred rate; and means for pacing the atrium of the heart at an advantageous atrial rate while the desired ventricular rate is greater than the preferred rate.
means for selecting an advantageous atrial rate;
means for selecting a desired ventricular rate;
means for pacing the ventricle of the heart at the desired ventricular rate;
means for pacing the atrium of the heart at twice the desired ventricular rate while the desired ventricular rate is lest than the preferred rate; and means for pacing the atrium of the heart at an advantageous atrial rate while the desired ventricular rate is greater than the preferred rate.
9. The device of claim 8 wherein the advantageous atrial rate is between about 120 beats per minute and about 180 beats per minute.
10. The device of claim 9 wherein the advantageous atrial rate is about 160 beats per minute.
11. The device of claim 9 or 10 wherein the preferred rate is between about 60 beats per minute and about 100 beats per minute.
12. The device of claim 11 wherein the preferred rate is about 80 beats per minute.
13. The device of claim 8 wherein the means for selecting the desired ventricular rate includes means for sensing spontaneous ventricular signals and means for determining a desired ventricular rate in response to sensed ventricle signals.
14. The device of claim 8 wherein an initial pulse is delivered synchronously with each ventricle pulse.
15. The device of claim 8 wherein the ventricular pulse is delivered synchronously with each atrial pulse while the desired ventricular rate is greater than the preferred rate.
16. The device of claim 8 wherein a ventricle pulse is delivered synchronously with one out of two atrial pulses while the desired ventricular rate is less than the preferred rate.
The amendments provided by new claims 1-16 do not have any impact on the description or the drawings.
The documents considered to be relevant have been reviewed and, in the opinion of the Applicant, these references, either individually or in combination, do neither anticipate nor render obvious tire inventive elements of the present invention. Claims 1-8 have been cancelled and new claims 1-16 have been written to comply with rule 39.1 (iv). Applicant intends to comply with any other matters of formality when the application enters the national stage.
Accordingly, the new claims 1-16 clearly are novel and present an inventive step over the cited references identified in the ;International Search Report.
The amendments provided by new claims 1-16 do not have any impact on the description or the drawings.
The documents considered to be relevant have been reviewed and, in the opinion of the Applicant, these references, either individually or in combination, do neither anticipate nor render obvious tire inventive elements of the present invention. Claims 1-8 have been cancelled and new claims 1-16 have been written to comply with rule 39.1 (iv). Applicant intends to comply with any other matters of formality when the application enters the national stage.
Accordingly, the new claims 1-16 clearly are novel and present an inventive step over the cited references identified in the ;International Search Report.
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US10/003,936 | 2001-10-30 | ||
US10/003,936 US6668195B2 (en) | 2001-10-30 | 2001-10-30 | Methods and apparatus for reducing the likelihood of atrial fibrillation |
PCT/US2002/031286 WO2003037426A1 (en) | 2001-10-30 | 2002-10-01 | Methods and apparatus for reducing the likelihood of atrial fibrillation |
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CA2460033A1 true CA2460033A1 (en) | 2003-05-08 |
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CA002460033A Abandoned CA2460033A1 (en) | 2001-10-30 | 2002-10-01 | Methods and apparatus for reducing the likelihood of atrial fibrillation |
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US (1) | US6668195B2 (en) |
EP (1) | EP1441808B1 (en) |
JP (1) | JP3947738B2 (en) |
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CA (1) | CA2460033A1 (en) |
DE (1) | DE60203318T2 (en) |
WO (1) | WO2003037426A1 (en) |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8086315B2 (en) | 2004-02-12 | 2011-12-27 | Asap Medical, Inc. | Cardiac stimulation apparatus and method for the control of hypertension |
US8165674B2 (en) | 2005-03-02 | 2012-04-24 | Backbeat Medical, Inc. | Methods and apparatus to increase secretion of endogenous naturetic hormones |
US7869874B2 (en) | 2006-09-25 | 2011-01-11 | G&L Consulting, Llc | Methods and apparatus to stimulate heart atria |
US8340763B2 (en) | 2008-09-08 | 2012-12-25 | Backbeat Medical, Inc. | Methods and apparatus to stimulate heart atria |
US10695126B2 (en) | 2008-10-06 | 2020-06-30 | Santa Anna Tech Llc | Catheter with a double balloon structure to generate and apply a heated ablative zone to tissue |
US9008769B2 (en) | 2012-12-21 | 2015-04-14 | Backbeat Medical, Inc. | Methods and systems for lowering blood pressure through reduction of ventricle filling |
US9370662B2 (en) | 2013-12-19 | 2016-06-21 | Backbeat Medical, Inc. | Methods and systems for controlling blood pressure by controlling atrial pressure |
BR112015017891A2 (en) * | 2013-12-20 | 2017-07-11 | Koninklijke Philips Nv | apparatus for determining the occurrence of a qrs complex in captured ecg data of an individual being monitored, apparatus for detecting the occurrence of a qrs complex in captured ecg data of an individual being monitored, ecg monitoring system, method intended for to determine the occurrence of a qrs complex in captured ecg data of an individual being monitored, and method for detecting the occurrence of a qrs complex in captured ecg data of an individual being monitored. |
US10342982B2 (en) | 2015-09-11 | 2019-07-09 | Backbeat Medical, Inc. | Methods and systems for treating cardiac malfunction |
US10485658B2 (en) | 2016-04-22 | 2019-11-26 | Backbeat Medical, Inc. | Methods and systems for controlling blood pressure |
US11331140B2 (en) | 2016-05-19 | 2022-05-17 | Aqua Heart, Inc. | Heated vapor ablation systems and methods for treating cardiac conditions |
Family Cites Families (63)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4059116A (en) | 1974-12-09 | 1977-11-22 | Medtronic, Inc. | Synchronous pacemaker with upper rate stabilization and method of use |
US4312355A (en) | 1977-01-12 | 1982-01-26 | Medtronic B.V. | Heart pacemaker |
US4248238A (en) | 1979-03-26 | 1981-02-03 | Joseph Simon P | Heart stimulating apparatus |
US4280502A (en) | 1979-08-08 | 1981-07-28 | Intermedics, Inc. | Tachycardia arrester |
US4284082A (en) | 1979-12-12 | 1981-08-18 | Medtronic B.V.Kerkrade | Ventricular synchronized atrial pacemaker and method of operation |
US4343311A (en) | 1980-04-30 | 1982-08-10 | Medtronic, Inc. | Atrial refractory control for R-wave rejection in pacemakers |
US4421116A (en) | 1980-10-14 | 1983-12-20 | Medtronic, Inc. | Heart pacemaker with separate A-V intervals for atrial synchronous and atrial-ventricular sequential pacing modes |
US4363325A (en) | 1981-01-19 | 1982-12-14 | Medtronic, Inc. | Mode adaptive pacer |
US4407287A (en) | 1981-02-17 | 1983-10-04 | Medtronic, Inc. | Atrial and ventricular-only pacemaker responsive to premature ventricular contractions |
US4401119A (en) | 1981-02-17 | 1983-08-30 | Medtronic, Inc. | Prolongation of timing intervals in response to ectopic heart beats in atrial and ventricular pacemakers |
US4452248A (en) | 1981-10-13 | 1984-06-05 | Keller Jr J Walter | Bidirectional pacemaker |
US4428378A (en) | 1981-11-19 | 1984-01-31 | Medtronic, Inc. | Rate adaptive pacer |
SE8107269L (en) | 1981-12-04 | 1983-06-05 | Siemens Elema Ab | DEVICE FOR ENDING A TAKYCARDI |
US4429697A (en) | 1982-04-12 | 1984-02-07 | Telectronics Pty. Ltd. | Dual chamber heart pacer with improved ventricular rate control |
DE3240430A1 (en) | 1982-11-02 | 1984-05-03 | Siemens AG, 1000 Berlin und 8000 München | METHOD AND PACEMAKER TO END TACHYCARDIA |
US4554921A (en) | 1983-02-11 | 1985-11-26 | Vitafin N.V. | Dual chamber pacemaker with automatic high rate limit mode determination |
US4523593A (en) | 1983-06-15 | 1985-06-18 | Medtronic, Inc. | Constant A-A interval control for DVI and DDD cardiac pacemakers |
US4527568A (en) | 1983-12-27 | 1985-07-09 | Vitafin N.V. | Dual chamber pacer with alternative rate adaptive means and method |
US4515161A (en) | 1984-01-10 | 1985-05-07 | Vitafin N.V. | Dual chamber pacemaker system with V-A time measurement apparatus and method |
US4624260A (en) | 1985-05-07 | 1986-11-25 | Intermedics, Inc. | Pacemaker with conditional atrial tracking capability |
US4738250A (en) | 1985-10-01 | 1988-04-19 | Mems Technology, Incorporated | Apparatus and method for micro-electric medical stimulation of cells of living animal tissue |
DE3535568A1 (en) | 1985-10-04 | 1987-04-09 | Siemens Ag | Atrial controlled pacemaker |
US4890617A (en) | 1987-11-25 | 1990-01-02 | Medtronic, Inc. | Dual chamber activity responsive pacer |
US5154172A (en) | 1989-11-13 | 1992-10-13 | Cyberonics, Inc. | Constant current sources with programmable voltage source |
US5052388A (en) | 1989-12-22 | 1991-10-01 | Medtronic, Inc. | Method and apparatus for implementing activity sensing in a pulse generator |
US4998974A (en) | 1990-01-05 | 1991-03-12 | Telectronics Pacing Systems, Inc. | Apparatus and method for antitachycardia pacing in dual chamber arrhythmia control system |
US5144947A (en) | 1990-04-03 | 1992-09-08 | Telectronics Pacing Systems, Inc. | Apparatus and method for antitachycardia pacing in a arrhythmia control systems |
US5086772A (en) | 1990-07-30 | 1992-02-11 | Telectronics Pacing Systems, Inc. | Arrhythmia control system employing arrhythmia recognition algorithm |
US5107850A (en) | 1990-11-02 | 1992-04-28 | Cardiac Pacemakers, Inc. | Method and apparatus for classifying and treating cardiac arrhythmias based on atrial and ventricular activity |
US5193550A (en) | 1990-11-30 | 1993-03-16 | Medtronic, Inc. | Method and apparatus for discriminating among normal and pathological tachyarrhythmias |
US5133350A (en) | 1991-01-31 | 1992-07-28 | Medtronic, Inc. | Mode switching pacemaker |
US5144949A (en) | 1991-03-15 | 1992-09-08 | Medtronic, Inc. | Dual chamber rate responsive pacemaker with automatic mode switching |
US5335657A (en) | 1991-05-03 | 1994-08-09 | Cyberonics, Inc. | Therapeutic treatment of sleep disorder by nerve stimulation |
US5215089A (en) | 1991-10-21 | 1993-06-01 | Cyberonics, Inc. | Electrode assembly for nerve stimulation |
JP2709981B2 (en) | 1992-02-03 | 1998-02-04 | メドトロニック インコーポレーテッド | Two-chamber cardiac pacemaker |
JPH07504596A (en) | 1992-06-30 | 1995-05-25 | メドトロニック インコーポレーテッド | Electrical medical stimulators and electrical stimulation methods |
SE9202825D0 (en) * | 1992-09-30 | 1992-09-30 | Siemens Elema Ab | HJAERTSTIMULATOR |
US5391185A (en) | 1993-02-22 | 1995-02-21 | Angeion Corporation | Atrial cardioverter with ventricular protection |
US5403356A (en) | 1993-04-28 | 1995-04-04 | Medtronic, Inc. | Method and apparatus for prevention of atrial tachy arrhythmias |
US5411524A (en) | 1993-11-02 | 1995-05-02 | Medtronic, Inc. | Method and apparatus for synchronization of atrial defibrillation pulses |
US5562708A (en) | 1994-04-21 | 1996-10-08 | Medtronic, Inc. | Method and apparatus for treatment of atrial fibrillation |
DE69509650T2 (en) | 1994-04-21 | 1999-12-30 | Medtronic Inc | TREATMENT OF ATRIAL FIBRILLATIONS |
US5522852A (en) | 1994-04-26 | 1996-06-04 | Incontrol, Inc. | Selective cardiac activity analysis atrial fibrillation detection system and method and atrial defibrillator utilizing same |
US5601615A (en) | 1994-08-16 | 1997-02-11 | Medtronic, Inc. | Atrial and ventricular capture detection and threshold-seeking pacemaker |
US5549642A (en) | 1994-08-19 | 1996-08-27 | Medtronic, Inc. | Atrial defibrillator and method of use |
US5480413A (en) | 1994-11-30 | 1996-01-02 | Telectronics Pacing Systems, Inc. | Apparatus and method for stabilizing the ventricular rate of a heart during atrial fibrillation |
US5609613A (en) | 1995-05-03 | 1997-03-11 | Intermedics, Inc. | Control of pacing rate in dual-chamber, rate-adaptive pacemakers |
US5630834A (en) | 1995-05-03 | 1997-05-20 | Medtronic, Inc. | Atrial defibrillator with means for delivering therapy in response to a determination that the patient is likely asleep |
US5814083A (en) | 1995-09-29 | 1998-09-29 | Medtronic, Inc | Pacemaker tachy determination based blocked on 2:1 sensing |
US5700282A (en) | 1995-10-13 | 1997-12-23 | Zabara; Jacob | Heart rhythm stabilization using a neurocybernetic prosthesis |
US5690681A (en) | 1996-03-29 | 1997-11-25 | Purdue Research Foundation | Method and apparatus using vagal stimulation for control of ventricular rate during atrial fibrillation |
US5690686A (en) | 1996-04-30 | 1997-11-25 | Medtronic, Inc. | Atrial defibrillation method |
US5792193A (en) | 1996-11-05 | 1998-08-11 | Vitatron Medical, B.V. | Pacemaker system and method with ventricular rate smoothing during high rate atrial arrhythmia |
US5840079A (en) | 1997-03-27 | 1998-11-24 | Medtronic, Inc. | Method and apparatus for treatment of atrial fibrillation |
US5954755A (en) | 1997-06-06 | 1999-09-21 | Medtronic, Inc. | Facilitated atrial pacing threshold testing |
US5928271A (en) | 1998-02-25 | 1999-07-27 | Medtronic, Inc. | Atrial anti-arrhythmia pacemaker and method using high rate atrial and backup ventricular pacing |
US6246906B1 (en) * | 1998-03-19 | 2001-06-12 | Cardiac Pacemakers, Inc. | System and method for treating atrial arrhythmias |
US6161047A (en) | 1998-04-30 | 2000-12-12 | Medtronic Inc. | Apparatus and method for expanding a stimulation lead body in situ |
US5876422A (en) | 1998-07-07 | 1999-03-02 | Vitatron Medical B.V. | Pacemaker system with peltier cooling of A-V node for treating atrial fibrillation |
US6292701B1 (en) | 1998-08-12 | 2001-09-18 | Medtronic Xomed, Inc. | Bipolar electrical stimulus probe with planar electrodes |
US6280414B1 (en) | 1998-09-30 | 2001-08-28 | Medtronic Ave, Inc. | Method and apparatus for local delivery of therapeutic agent |
US6256537B1 (en) | 1999-03-17 | 2001-07-03 | Medtronic, Inc. | Pacemaker system with inhibition of AV node for rate regulation during atrial fibrillation |
US6272380B1 (en) | 1999-08-19 | 2001-08-07 | Medtronic, Inc. | Apparatus for treating atrial tachy arrhythmias with synchronized shocks |
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- 2002-10-01 EP EP02773690A patent/EP1441808B1/en not_active Expired - Lifetime
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- 2002-10-01 CA CA002460033A patent/CA2460033A1/en not_active Abandoned
- 2002-10-01 WO PCT/US2002/031286 patent/WO2003037426A1/en active IP Right Grant
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- 2002-10-01 DE DE60203318T patent/DE60203318T2/en not_active Expired - Lifetime
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WO2003037426A1 (en) | 2003-05-08 |
US20030083706A1 (en) | 2003-05-01 |
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JP2005507719A (en) | 2005-03-24 |
JP3947738B2 (en) | 2007-07-25 |
DE60203318T2 (en) | 2005-07-21 |
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