Source: https://patents.google.com/patent/US6442427B1/en
Timestamp: 2019-03-23 18:07:05
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Matched Legal Cases: ['art 8', 'art 8', 'art 8', 'art 8', 'art 8', 'art 8', 'art 8', 'art 8', 'art 8', 'art\n2000']

US6442427B1 - Method and system for stimulating a mammalian heart - Google Patents
Method and system for stimulating a mammalian heart Download PDF
US6442427B1
US6442427B1 US09/559,048 US55904800A US6442427B1 US 6442427 B1 US6442427 B1 US 6442427B1 US 55904800 A US55904800 A US 55904800A US 6442427 B1 US6442427 B1 US 6442427B1
US09/559,048
2000-04-27 Application filed by Medtronic Inc filed Critical Medtronic Inc
2000-04-27 Priority to US09/559,048 priority Critical patent/US6442427B1/en
2001-08-30 Assigned to MEDTRONIC, INC. reassignment MEDTRONIC, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BOUTE, WILLEM, VAN BOLHUIS, HARM HUGO
2002-08-27 Publication of US6442427B1 publication Critical patent/US6442427B1/en
A method for instantaneously stimulating a mammalian heart is provided. The mammalian heart includes a first atrium and a second atrium. A commencement signal is received. At least one additional signal is received. A plurality of intervals corresponding to the time between two successive signals is measured. An average interval is calculated. One of the plurality of intervals is compared to the average interval. Finally, a contraction signal is instantly transmitted to the second atrium when a difference between the average interval and one of the plurality of intervals is greater than a predetermined time period, instantaneously transmitting a contraction signal to the second atrium.
The present invention relates to cardial pacing systems, and, in particular, to cardial pacing systems providing for the immediate contractual stimulation of an atrium of a mammalian heart upon the detection of a premature atrial contraction in a second atrium.
The cardiovascular system provides oxygenated blood to various structures of the body. In a normally functioning heart, the body's demand for oxygenated blood varies, and the heart responds by increasing or decreasing its rate and force of contraction to meet the demand. An electrical signal generated by the sinus node in the upper right atrial wall near the base of the heart is transmitted through the two upper heart chambers, i.e., the right and left atria, which causes them to synchronously contract. The contraction of the two upper heart chambers forces blood, pooled within the chambers, through open heart valves and into the right and left ventricles, the two lower heart chambers. The atrial electrical depolarization wave arrives at the atrio-ventricular (AV) node, superior to the ventricles, and triggers the conduction of a ventricular depolarization wave down the bundle of His in the septum between the right and left ventricles to the apex of the heart. The two ventricles contract after a brief AV delay time following the sinus node depolarization as the depolarization wave then advances superiorly, posteriorly, and anteriorly throughout the outer ventricular wall of the heart. The two lower heart chambers contract and force the blood through the vascular system of the body. The contraction of the right and left ventricles then proceeds in an organized fashion which optimizes the emptying of the ventricular chambers. The synchronous electrical depolarization of the atrial and ventricular chambers can be electrically sensed and displayed, and the electrical waveform is characterized by accepted convention as the “PQRST” complex. The PQRST complex includes the P-wave, which corresponds to the atrial depolarization wave; the R-wave, corresponding to the ventricular depolarization wave; and the T-wave, which represents the re-polarization of the cardiac cells.
A number of proposals have been advanced for providing pacing therapies to alleviate theses conditions and restore synchronous depolarization of right and left, upper and lower, heart chambers. The proposals appearing in U.S. Pat. Nos. 3,937,266, 4,088,140, 4,548,203, 4,458,677 and 4,332,259 are summarized in U.S. Pat. Nos. 4,928,688 and 5,674,259, all incorporated herein by reference. The advantages of providing sensing at pace/sense electrodes located in both the right and left heart chambers are addressed in the '688 and '259 patents, as well as in U.S. Pat. Nos. 4,354,497, 5,174,289, 5,267,560, 5,514,161, 5,584,867, also all incorporated herein by reference. Typically, the right atrium is paced at expiration of an A-A escape interval, and the left atrium is simultaneously paced or synchronously paced after a short delay time. Similarly, the right ventricle is paced at expiration of a V-V escape interval, and the left ventricle is simultaneously paced or synchronously paced after a short delay. Some of these patents propose limited forms of DDD pacing having “bi-ventricular” or “bi-atrial” demand or triggered pacing functions. In all cases, a pacing pulse delivered at the end of the escape internal or AV delay (a “paced event”) triggers the simultaneous or slightly delayed delivery of the pacing pulse to the other heart chamber. They do not propose pacing a right or left heart chamber at the end of the escape interval or AV delay and then inhibiting pacing in the other of the right or left heart chamber if a conducted depolarization is detected in that other heart chamber within a physiologic time related to the location of the pace/sense electrodes.
A double atrial, triple chamber pacing system is described in the '161 and '867 patents. Such a pacing system is used for treating dysfunctional atrial conduction using a programmable DDD pacemaker for pacing both atria simultaneously when an atrial sensed event is detected from either chamber or at the expiration of a V-A escape interval. The IPG includes atrial sense amplifiers coupled to atrial pace/sense electrodes positioned with respect to electrode sites in or adjacent the right and left atria and a ventricular sense amplifier coupled to ventricular pace/sense electrodes located in or on the right ventricle. In the '161 patent, ventricular pacing pulses are applied to the ventricular pace/sense electrodes at the end of an AV delay timed from the atrial paced events unless the sensed atrial rate exceeds a rate limit. In the '867 patent, a fall back mode is commenced to limit the ventricular pacing rate if the sensed P-wave are deemed “premature”. Clinical experience in use of double atrial, three chamber, pacing systems appears in abstracts by Daubert et al., including “Permanent Dual Atrium Pacing in Major Intratrial Conduction Blocks: A Four Years Experience” appearing in PACE (Vol.16, Part II, NASPE Abstract 141, p. 885, April 1993). In these systems, atrial pacing pulses are delivered simultaneously in a triggered mode to both atria that is wasteful of electrical energy and fails to maintain a physiologic delay between the evoked depolarizations of the atria.
Further clinical experience with two, three and four heart chamber pacing is also reported by Daubert et al. in “Permanent Left Ventricular Pacing With Transvenous Leads Inserted Into The Coronary Veins” appearing in PACE (Vol. 21, Part II, pp. 239-245, January 1998). In the two heart chamber context, there is disclosed a method of implanting conventional DDDR IPGs with the atrial pace/sense terminals coupled to a left ventricular lead having pace/sense electrodes located in relation to the left ventricle. The ventricular pace/sense terminals were coupled to right ventricular leads having pace/sense electrodes located in relation to the right ventricle. The IPG was programmed to operate in the WIR mode with short AV delays, e.g. 30 ms, for timing delivery of a pacing pulse to the right ventricle when an R-wave was first sensed in or a pacing pulse was delivered to the left ventricle at the end of the programmed V-A escape interval. In this bi-ventricular pacing system, ventricular pacing pulses were not delivered in a triggered mode to both ventricles, but only the conduction delay from the left ventricle to the right ventricle could be programmed.
A four chamber DDD pacing system providing right and left chamber pacing and sensing is described in the above article, and in an article by Cazeau et al., entitled “Four Chamber Pacing in Dilated Cardiomyopathy” appearing in PACE (Vol. 17, Part II, pp. 1974-1979, November 1994). In these and other four chamber systems, right and left atrial leads are coupled “in series” through a bifurcated bipolar adaptor with atrial pace/sense connector block terminals, and right and left ventricular leads are coupled “in series” through a bifurcated bipolar adaptor with ventricular pace/sense connector block terminals. Right atrial and right ventricular leads are connected to the cathode ports, while left atrial and left ventricular leads are connected to the anode ports of each bipolar bifurcated adaptor. The IPG is programmed in the DDD mode and in a bipolar pacing mode with a common AV delay that is connected by the delivery of atrial pacing pulses. The earliest right or left atrial sensed event (i.e., the P-wave) within a V-A escape interval or the expiration of the V-A escape interval triggers delivery of atrial pacing pulses to both of the pace/sense electrodes in both atrial chambers through the series connected, right and left atrial leads. It appears that the sensing “in series” of either a right or left ventricular R-wave across the right and left pace/sense electrode during the AV delay terminates the AV delay and triggers delivery of ventricular pace pulses across the right and left pace/sense electrode pair. In this pacing system, both atrial and ventricular pacing pulses are delivered to both atria and both ventricles on the sensing the P-wave and on the sensing R-wave, respectively, which is wasteful of electrical energy. Furthermore, the resulting simultaneous depolarization of the right and left atria or the right and left ventricles in not physiologically beneficial in many instances.
In these approaches, the atrial and/or ventricular pace/sense electrodes are located in a variety of locations and manner with respect to the right and left atria and/or the right and left ventricles. In the '688 patent, one ventriclar pace/sense electrode is located at the distal end of an endocardial lead introduced deeply into the great vein extending from the coronary sinus to place it adjacent to the left ventricle. It is also known that pace/sense electrode of an endocardial lead can be placed closer to the entrance to the coronary sinus and adjacent the left atrium. Such an approach is shown in the above referenced Cazeau et al. article and in an abstract by Daubert et al., “Renewal of Permanent Left Atrial Pacing via the Coronary Sinus”, appearing in PACE (Vol. 15, Part II, NASPE Abstract 255, p. 572, April 1992), also incorporated herein by reference. Epicardial screw-in, pace/sense electrodes can also be placed epicardially on the right and left ventricles because the myocardial walls are thick enough to not be perforated in the process as also shown in the above referenced Cazeau article. In addition, a bi-ventricular pacemaker is proposed in the above-incorporated '259 patent having an array of ventricular pace/sense electrodes fitting about the apex of the heart to provide a plurality of usable epicardial pacing and/or sensing electrode sites about the apical region of the heart.
Additionally, “Coronary Sinus Pacing Prevents Induction of Atrial Fibrillation,” by Papageorgiou et al., proposes a simultaneous high right atrial and coronary sinus pacing to prevent the induction of atrial fibrillation. That is, Papageorgiou proposes that distal coronary sinus pacing suppresses the propensity of high right atrial extra stimulus to induce atrial fibrillation by limiting their prematurity at the posterior triangle of Koch, while not allowing local conduction delay and local reentry to occur.
Furthermore, in “Multiple Channel, Sequential, Cardiac Pacing Systems,” Struble et al. discloses an invention directed to providing symmetrically operating left and right heart chamber pacing systems. The pacing systems described in Struble overcome the problems and limitations, disclosed and described above, and provide a great deal of flexibility in tailoring the delivered pacing therapy to needs of the individual patient's heart.
Finally, in the Diva Functional Product Description, Regarding PVC synchronous atrial stimulation, a Vitatron device allows for PVC synchronous pacing. That is, when the mode of the pacing system is programmed to ‘On,’ the PVC synchronous atrial pacing feature paces the atrium of the patient's heart within 20 ms after recording a single PVC event. Furthermore, no atrial pacing function is released from the pacing system within a predetermined period of time from the last event, and the PVC synchronous atrial pacing feature is limited to the first PVC in a row of PVCs.
3,937,266 02-10-76 Cordone et al.
4,088,140 05-09-78 Rockland et al.
4,332,259 06-01-82 McCorkle, Jr.
4,354,497 10-19-82 Kahn
4,458,677 07-10-84 McCorkle, Jr.
4,548,203 10-22-85 Tracker, Jr. et al.
4,928,688 05-29-90 Mower
5,174,289 12-29-92 Cohen
5,267,560 12-07-93 Cohen
5,514,161 05-07-96 Limousin
5,584,867 12-17-96 Limousin et al.
5,674,259 10-07-97 Gray
The present invention is therefore directed to providing a method and system for instantaneously stimulating the contraction of an atrium of a mammalian heart. Such a system of the present invention overcomes the problems, disadvantages and limitations of the prior art described above, and provides a more efficient and accurate means of immediately contractually stimulating the left atrium of a mammalian heart.
FIG. 1 is a simplified schematic view of one embodiment of implantable medical device (“IMD”) 10 of the present invention. The IMD 10 shown in FIG. 1 is a pacemaker comprising at least one of pacing and sensing leads 16 and 18 attached to hermetically sealed enclosure 14 and implanted near human or mammalian heart 8. Pacing and sensing leads 16 and 18 sense electrical signals attendant to the depolarization and re-polarization of the heart 8, and further provide pacing pulses for causing depolarization of cardiac tissue in the vicinity of the distal ends thereof. Leads 16 and 18 may have unipolar or bipolar electrodes disposed thereon, as is well known in the art. Examples of IMD 10 include implantable cardiac pacemakers disclosed in U.S. Pat. No. 5,158,078 to Bennett et al., U.S. Pat. No. 5,312,453 to Shelton et al. or U.S. Pat. No. 5,144,949 to Olson, all of which are hereby incorporated by reference, each in their respective entireties.
A dual-chamber pacemaker may be used in a bi-atrial pacing system, such as that used in an embodiment of the present invention, to alleviate the problems caused by unstable atrial arrythmias, such as, for example, atrial tachyarrythmia. One lead (such as, for example, the sensing lead 7 including electrodes 9, 13 in FIG. 4) is preferably placed in the right atrium of the mammalian heart 8. A second lead (such as, for example, a pacing lead 41 including electrode 21 in FIG. 4) is preferably placed in the coronary sinus (i.e., the left atrium). Alternatively, the sensing lead 7 may be placed in the left atrium, and the pacing lead 41 in the right. As a result, a sensed or paced event (preferably corresponding to a PAC) in the “sensed” atrium may trigger the immediate contractual stimulation of the “paced” atrium. The “AV-delay,” or, in this case, the delay between the first and second atrial pacing signals, is preferably very short. The purpose for this short delay is to ensure the instantaneous contractual stimulation of the left atrium (i.e., the resetting of the sinusrhythm). Additionally, it should be noted that in such a pacing therapy, it would preferably be optimal to have the option to program the AV-delay to 0 ms (or, potentially, even a negative value) in order to obtain optimal synchrony between the atria and the ventricles on both the right and left sides of the heart 8.
FIG. 6 depicts a flow chart illustrating one embodiment of an algorithm for instantaneously stimulating the contraction of an atrium of a mammalian heart 8 after a PAC has been detected, in accordance with the present invention. In Blocks 100 and 200, the IMD 10 (or, more specifically, the microprocessor 64 within the IMD 10) begins to receive heartbeats from one atrium (the “sensed” atrium) of the mammalian heart 8. Preferably, the reception of the heartbeats may occur through the following method. First, the microprocessor 64 receives a commencement signal from one of the sensing leads 7 disposed in the sensed atrium. This is shown in Block 100. Second, in Block 200, the microprocessor 64 receives another signal from the sensing lead 7. Preferably, both of the signals received correspond to a heartbeat of the mammalian heart 8. Alternatively, the signals may correspond to other events of the mammalian heart 8 which may signify the start of a PAC.
In Block 600, if the difference between the interval and average interval is less than the predetermined factor (i.e., if a PAC is not detected), the microprocessor 64 continues to process the signals from the sensing lead. However, upon the detection of a PAC in the first atrium (i.e., in which case the difference between the interval and average interval is greater than the predetermined factor), the IMD 10 then immediately transmits a signal to the “paced” atrium (Block 700). That is, the microprocessor 64 transmits the signal, via a data communication bus 72, to the digital controller 74, which then transmits the signal through the output amplifier 96 to the mammalian heart 8 via pacing lead 41. The electrical signal transmitted to the “paced” atrium stimulates the “paced” atrium to contract. Additionally, the transmission of the signal to the “paced” atrium, and the subsequent contraction thereof, occurs instantaneously. That is, there is no measurable delay between the steps of detecting the PAC, transmitting the signal from the IMD 10 to the “paced” atrium and contracting the “paced” atrium. At this point, the microprocessor 64 returns to Block 200, to resume the monitoring process, described above, continuing the detection of potential PACs.
1. A method for instantaneously stimulating a mammalian heart, the mammalian heart including a first atrium and a second atrium, comprising:
receiving a commencement signal;
receiving at least one additional signal;
measuring a plurality of intervals corresponding to the time between two successive signals;
calculating an average interval;
comparing one of the plurality of intervals to the average interval; and
when a difference between the average interval and one of the plurality of intervals is greater than a predetermined time period, instantaneously transmitting a contraction signal to the second atrium.
2. The method of claim 1, wherein the commencement signal is transmitted from the first atrium.
at least one sensing lead operably connected to the controller; and
a signal is instantaneously sent from the controller to one of the at least one pacing leads to contract a paced atrium when at least one interval calculated from at least two signals received from a sensed atrium via one of the at least one sensing leads is less than an average interval by a predetermined time factor.
14. The implantable medical device of claim 13, wherein each of the at least one sensing leads has one end, the one end being positioned in the sensed atrium.
means for receiving a commencement signal;
means for receiving at least one additional signal;
means for measuring a plurality of intervals corresponding to the time between two successive signals;
means for calculating an average interval;
means for comparing one of the plurality of intervals to the average interval; and
when a difference between the average interval and one of the plurality of intervals is greater than a predetermined time period, means for instantaneously transmitting a contraction signal to the second atrium.
31. The implantable medical device system of claim 30, wherein the commencement signal is transmitted from the first atrium.
when a difference between the average interval and one of the plurality of intervals is greater than a predetermined time period, transmitting a contraction signal to the left atrium.
43. The method of claim 42, wherein the commencement signal is transmitted from the right atrium.
US09/559,048 2000-04-27 2000-04-27 Method and system for stimulating a mammalian heart Expired - Fee Related US6442427B1 (en)
US09/559,048 US6442427B1 (en) 2000-04-27 2000-04-27 Method and system for stimulating a mammalian heart
DE2001120310 DE10120310A1 (en) 2000-04-27 2001-04-26 Method and system for pacing a heart of a mammal
FR0105743A FR2808214B1 (en) 2000-04-27 2001-04-27 Method and system for stimulating a heart of mammal
US6442427B1 true US6442427B1 (en) 2002-08-27
US09/559,048 Expired - Fee Related US6442427B1 (en) 2000-04-27 2000-04-27 Method and system for stimulating a mammalian heart
2000-04-27 US US09/559,048 patent/US6442427B1/en not_active Expired - Fee Related
2001-04-26 DE DE2001120310 patent/DE10120310A1/en not_active Withdrawn
2001-04-27 FR FR0105743A patent/FR2808214B1/en not_active Expired - Fee Related
"Diva Functional Product Description" by Vitatron (product description of a PVC synchronous pacing device).
Cazeau et al, "Four Chamber Pacing in Dilated Cardiomyopathy" PACE (vol.17 Part II), p.1974-1979, Nov. 1994.
Daubert et al, "Permanent Atrial Resynchronization by synchronous bi-strial Pacing in the Preventive Treatment of Atrial Flutter Associated with High Degree Interatrial Block", Arch Mal Coeur Vaiss, 1994 Nov. 1987 (11 Suppl), pp. 1535-1546.
Daubert et al, "Permanent Left Ventricular Pacing with transvenous Leads inserted into the coronary veins" PACE (vol. 21 Part II) p. 239-245, Jan. 1998.
Daubert et al, Permanent Dual Atrium Pacing in Major Intratrial Conduction Blocks: a four years experience. PACE (vol. 16. Part II) Naspe abstract 141, p. 885, Apr. 1993.
Daubert et al. Renewal of Permanent Left Atrial Pacing via the Coronary Sinus: PACE (vol. 15, Part II) NASPE Abstract 255 p. 572, Apr. 1992.
Papageorgiou et al, "Coronary Sinus Pacing Prevents Induction of Atrial Fibrillation", Circulation, 1997, Sep. 16, vol. 96, No.6, pp. 1893-1898.
WO2007127553A1 (en) * 2006-04-26 2007-11-08 Medtronic, Inc. Method and apparatus for prevention of atrial tachyarrhythmias
FR2808214A1 (en) 2001-11-02
DE10120310A1 (en) 2001-12-06
FR2808214B1 (en) 2006-02-17
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BOUTE, WILLEM;VAN BOLHUIS, HARM HUGO;REEL/FRAME:012334/0586