text:
Patent US7363083 - Flexible subcutaneous implantable cardioverter-defibrillator - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsOne embodiment of the present invention provides an implantable cardioverter-defibrillator for subcutaneous positioning over a patient's ribcage, the implantable cardioverter-defibrillator including a housing, wherein the housing conforms to the patient's ribcage when subcutaneously positioned; an electrode...http://www.google.com/patents/US7363083?utm_source=gb-gplus-sharePatent US7363083 - Flexible subcutaneous implantable cardioverter-defibrillatorAdvanced Patent SearchPublication numberUS7363083 B2Publication typeGrantApplication numberUS 11/112,159Publication dateApr 22, 2008Filing dateApr 22, 2005Priority dateSep 18, 2000Fee statusPaidAlso published asCA2465754A1, CA2465754C, EP1444007A1, EP1444007B1, US7120495, US20020103510, US20050192639, WO2003039668A1Publication number11112159, 112159, US 7363083 B2, US 7363083B2, US-B2-7363083, US7363083 B2, US7363083B2InventorsGust H. Bardy, Riccardo Cappato, William J. Rissmann, Alan H. Ostroff, Paul J. ErlingerOriginal AssigneeCameron Health, Inc.Export CitationBiBTeX, EndNote, RefManPatent Citations (99), Non-Patent Citations (15), Referenced by (3), Classifications (14), Legal Events (1) External Links: USPTO, USPTO Assignment, EspacenetFlexible subcutaneous implantable cardioverter-defibrillator
US 7363083 B2Abstract
One embodiment of the present invention provides an implantable cardioverter-defibrillator for subcutaneous positioning over a patient's ribcage, the implantable cardioverter-defibrillator including a housing, wherein the housing conforms to the patient's ribcage when subcutaneously positioned; an electrode disposed upon a portion of the housing; and an electrical circuit located within the housing, wherein the electrical circuit is electrically coupled to the electrode.
1. An implantable cardioverter/defibrillator of the type including a plurality of components, the implantable cardioverter/defibrillator comprising:
a battery, a capacitor, and circuitry connected thereto, the circuitry being configured for detecting an abnormal heart rhythm, charging the capacitor, and discharging the capacitor to provide a cardioversion/defibrillation shock;
a first structural portion supporting a first cardioversion/defibrillation electrode adapted to be implanted at a first subcutaneous implantation site about the patient's thorax and adapted to direct the first cardioversion/defibrillation electrode toward the patient's heart;
a second structural portion supporting a second cardioversion/defibrillation electrode adapted to be implanted at a second subcutaneous implantation site about the patient's thorax and adapted to direct the second cardioversion/defibrillation electrode toward the patient's heart; and
a connecting structure including one or more conductors connecting the first and second structural portions together,
wherein the components of the implantable cardioverter/defibrillator are distributed between the first and second structural portions, and the one or more conductors of the connecting structure interconnect the plurality of components to enable generation and delivery of cardioversion/defibrillation shocks between the first and second cardioversion/defibrillation electrodes.
2. The implantable cardioverter/defibrillator of claim 1, wherein the circuitry is adapted to detect tachycardias.
3. The implantable cardioverter/defibrillator of claim 1, wherein the first and second structural portions and the connecting structure are configured to enable implantation in a patient such that the heart will be disposed substantially between the first and second cardioversion/defibrillation electrodes.
4. The implantable cardioverter/defibrillator of claim 1, wherein the first structural portion is a first housing segment and the second structural portion is a second housing segment.
5. The implantable cardioverter/defibrillator of claim 1, wherein the first structural portion is a first canister section and the second structural portion is a second canister section.
6. The implantable cardioverter/defibrillator of claim 1, wherein the first and second structural portions are hermetically sealed.
7. The implantable cardioverter/defibrillator of claim 1, wherein the battery is enclosed within the second structural portion.
8. The implantable cardioverter/defibrillator of claim 1, wherein the capacitor and circuitry are enclosed within the first structural portion.
9. The implantable cardioverter/defibrillator of claim 1, wherein the connecting structure includes a first end and a second end, and is coupled at the first end to the first structural portion and at the second end to the second structural portion.
10. The implantable cardioverter/defibrillator of claim 1, wherein the connecting structure includes a first end and a second end, and wherein at least one of the first and second ends of the connecting structure can be disconnected from the respective first and second structural portions to enable replacement of the first or second structural portions.
11. The implantable cardioverter/defibrillator of claim 1, wherein the connecting structure includes a first end and a second end, and wherein the connecting structure is permanently coupled at the first end to the first structural portion and at the second end to the second structural portion.
12. The implantable cardioverter/defibrillator of claim 1, further including two or more far-field sensing electrodes adapted to provide far-field sensing of cardiac electrical activity.
13. The implantable cardioverter/defibrillator of claim 12, wherein the circuitry includes sensing circuitry coupled to the far-field sensing electrodes.
14. The implantable cardioverter/defibrillator of claim 1, wherein:
the first structural portion supports a first pacing electrode;
the second structural portion supports a second pacing electrode; and
the circuitry further comprises a pacing pulse generator for generating pacing pulses, the pacing pulse generator coupled to the first pacing electrode.
15. The implantable cardioverter/defibrillator of claim 14, wherein the connector structure comprises a pacing conductor coupled between the pacing pulse generator and the second pacing electrode, whereby the pacing pulse generator is configured to generate pacing pulses for delivery to the heart using the first and second pacing electrodes.
16. The implantable cardioverter/defibrillator of claim 1, further including a third cardioversion/defibrillation electrode and means for selectively delivering cardioversion/defibrillation shocks among selected pairs of the first, second and third cardioversion/defibrillation electrodes.
17. The implantable cardioverter/defibrillator of claim 1, further comprising means for selectively delivering cardioversion/defibrillation shocks having one of a monophasic waveform or a biphasic waveform.
18. An implantable cardioverter/defibrillator comprising:
a first structure supporting a first cardioversion/defibrillation electrode adapted to be implanted at a first subcutaneous implantation site about the patient's thorax and adapted to direct the first cardioversion/defibrillation electrode toward the patient's heart;
a second structure supporting a second cardioversion/defibrillation electrode adapted to be implanted at a second subcutaneous implantation site about the patient's thorax and adapted to direct the second cardioversion/defibrillation electrode toward the patient's heart,
a connection structure connecting the first and second structures together;
cardioversion/defibrillation shock generating means enclosed within the first or second structure and coupled to the first and second cardioversion/defibrillation electrodes;
a battery enclosed within the first or second structure and coupled to the cardioversion/defibrillation shock generating means; and
means for triggering generation and delivery of cardioversion/defibrillation shocks between the first and second cardioversion/defibrillation electrodes;
wherein the first and second structures and the connection structure are adapted to allow placement within a patient's body such that the patient's heart can be disposed substantially between the first and second cardioversion/defibrillation electrodes:
wherein the first structure is a first canister section and the second structure is a second canister section.
19. The implantable cardioverter/defibrillator of claim 18, wherein the first and second structures are hermetically sealed.
20. The implantable cardioverter/defibrillator of claim 18, wherein the means for triggering generation and delivery of cardioversion/defibrillation shocks comprises at least one capacitor, and circuitry for detecting a tachyarrhythmia, charging the capacitor, and discharging the capacitor to provide a cardioversion/defibrillation shock.
21. The implantable cardioverter/defibrillator of claim 18, wherein the battery is enclosed within the second structure.
22. The implantable cardioverter/defibrillator of claim 18, wherein the cardioversion/defibrillation shock generating means and the means for triggering generation and delivery of cardioversion/defibrillation shocks are enclosed within the first structure.
23. The implantable cardioverter/defibrillator of claim 18, wherein the first and second structures supporting the electrodes each include a first end and a second end, the first end being free and the second end being attached to the connection structure, the first and second structures also each including a width and a greater thickness; and wherein the free end of at least one of the first and second structures is tapered from the greater thickness to a lesser thickness to ease subcutaneous advancement.
24. An implantable cardioverter/defibrillator comprising:
wherein the first structure is a first housing segment and the second structure is a second housing; and
the first and second structures and the connection structure are adapted to allow placement within a patient's body such that the patient's heart can be disposed substantially between the first and second cardioversion/defibrillation electrodes.
25. A method of implanting an implantable cardioverter-defibrillator within a patient, the method comprising:
providing a cardioverter-defibrillator comprising a battery, one or more power capacitors, and control circuitry coupled thereto, as well as a first structural portion, a second structural portion and a connecting structure interconnecting the first and second structural portions, wherein the battery, one or more power capacitors, and control circuitry are distributed among the first and second structural portions, and each of the first and second structural portions includes a defibrillation electrode disposed thereon;
making a surgical incision into subcutaneous space between the patient's skin and ribcage;
inserting the first structural portion through the incision and advancing the first structural portion subcutaneously to a first subcutaneous implantation site;
inserting the second structural portion through the incision and advancing the second structural portion subcutaneously to a second subcutaneous implantation site spaced from the first subcutaneous implantation site so that the connecting structure is disposed subcutaneously between the first and second structural portions and the heart is disposed between the first and second defibrillation electrodes; and
26. The method of claim 25, wherein the first structural portion is a first housing segment and the second structural portion is a second housing segment.
27. The method of claim 25, wherein the first structural portion is a first canister section and the second structural portion is a second canister section.
28. The method of claim 25, wherein the first and second structural portions are hermetically sealed.
29. The method of claim 25, wherein the first and second structural portions each include a first end and a second end, the first end being free and the second end being attached to the connecting structure, the first and second structures also each including a width and a greater thickness; and wherein the free end of at least one of the first and second structural portions is tapered from the greater thickness to a lesser thickness to ease the subcutaneous inserting and advancing steps.
This application is a continuation of U.S. application Ser. No. 10/011,956, filed Nov. 5, 2001, now U.S. Pat. No. 7,120,495; which is a continuation-in-part of U.S. application Ser. No. 09/940,599, filed Aug. 27, 2001, now U.S. Pat. No. 6,950,705; which is a continuation-in-part of U.S. application Ser. No. 09/663,607, filed Sep. 18, 2000, now U.S. Pat. No. 6,721,597; and a continuation-in-part of U.S. application Ser. No. 09/663,606, filed Sep. 18, 2000, now U.S. Pat. No. 6,647,292, the entire disclosures of which are all incorporated herein by reference.
Defibrillation/cardioversion is a technique employed to counter arrhythmic heart conditions including some tachycardias in the atria and/or ventricles. Typically, electrodes are employed to stimulate the heart with electrical impulses or shocks, of a magnitude substantially greater than pulses used in cardiac pacing. Because current density is a key factor in both defibrillation and pacing, implantable devices may improve what is capable with the standard waveform where the current and voltage decay over the time of pulse deliver. Consequently, a waveform that maintains a constant current over the duration of delivery to the myocardium may improve defibrillation as well as pacing.
Defibrillation/cardioversion systems include body implantable electrodes that are connected to a hermetically sealed container housing the electronics, battery supply and capacitors. The entire system is referred to as implantable cardioverter/defibrillators (ICDs). The electrodes used in ICDs can be in the form of patches applied directly to epicardial tissue, or, more commonly, are on the distal regions of small cylindrical insulated catheters that typically enter the subclavian venous system, pass through the superior vena cava and, into one or more endocardial areas of the heart. Such electrode systems are called intravascular or transvenous electrodes. U.S. Pat. Nos. 4,603,705; 4,693,253; 4,944,300; and 5,105,810; the disclosures of which are all incorporated herein by reference, disclose intravascular or transvenous electrodes, employed either alone, in combination with other intravascular or transvenous electrodes, or in combination with an epicardial patch or subcutaneous electrodes. Compliant epicardial defibrillator electrodes are disclosed in U.S. Pat. Nos. 4,567,900 and 5,618,287, the disclosures of which are incorporated herein by reference. A sensing epicardial electrode configuration is disclosed in U.S. Pat No. 5,476,503, the disclosure of which is incorporated herein by reference.
Recent efforts to improve the efficiency of ICDs have led manufacturers to produce ICDs which are small enough to be implanted in the pectoral region. In addition, advances in circuit design have enabled the housing of the ICD to form a subcutaneous electrode. Some examples of ICDs in which the housing of the ICD serves as an optional additional electrode are described in U.S. Pat. Nos. 5,133,353; 5,261,400; 5,620,477; and 5,658,321, the disclosures of which are incorporated herein by reference.
FIG. 12 is a schematic view of yet a further embodiment where the canister of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient;
FIG. 13 is a schematic of a different embodiment where the canister of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient;
FIG. 16 is a schematic view of the method of making a subcutaneous path from the preferred incision for implanting the US-ICD;
FIG. 17 is a schematic view of an introducer for performing the method of US-ICD implantation;
FIG. 18 is an exploded schematic view of an alternate embodiment of the present invention with a plug-in portion that contains operational circuitry and means for generating cardioversion/defibrillation shock waves;
FIG. 26B is a front elevational view of the S-ICD canister of FIG. 26A depicting the curved proximal segment and the planar distal segment of the multi-segment canister housing;
FIG. 26C is a front elevational view of the S-ICD canister of FIG. 26A depicting the curved proximal segment and the curved distal segment of the multi-segment canister housing;
FIG. 27 is a perspective view of a US-ICD comprised, in part, of a compliant material;
FIG. 28A is a front elevational view of an alternative S-ICD canister of the present invention having a multi-segment canister housing;
FIG. 28B is an enlarged perspective view of a hinge of the multi-segment canister housing of FIG. 28A;
FIG. 29A is a bottom plan view of an alternative S-ICD canister of the present invention having a section of the canister housing that is pleated; and
FIG. 29B is a front elevational view of the S-ICD canister of FIG. 29A.
Turning now to FIG. 1, the S-ICD of the present invention is illustrated. The S-ICD consists of an electrically active canister 11 and a subcutaneous electrode 13 attached to the canister. The canister has an electrically active surface 15 that is electrically insulated from the electrode connector block 17 and the canister housing 16 via insulating area 14. The canister can be similar to numerous electrically active canisters commercially available in that the canister will contain a battery supply, capacitor and operational circuitry. Alternatively, the canister can be thin and elongated to conform to the intercostal space. The circuitry will be able to monitor cardiac rhythms for tachycardia and fibrillation, and if detected, will initiate charging the capacitor and then delivering cardioversion/defibrillation energy through the active surface of the housing and to the subcutaneous electrode. Examples of such circuitry are described in U.S. Pat. Nos. 4,693,253 and 5,105,810 the entire disclosures of which are herein incorporated by reference. The canister circuitry can provide cardioversion/defibrillation energy in different types of waveforms. In one embodiment, a 100 uF biphasic waveform is used of approximately 10-20 ms total duration and with the initial phase containing approximately ⅔ of the energy, however, any type of waveform can be utilized such as monophasic, biphasic, multiphasic or alternative waveforms as is known in the art.
Another optional aspect of the present invention is that the operational circuitry can detect the presence of atrial fibrillation as described in Olson, W. et al. �Onset And Stability For Ventricular Tachyarrhythmia Detection in an Implantable Cardioverter and Defibrillator,� Computers in Cardiology (1986) pp. 167-170. Detection can be provided via R-R Cycle length instability detection algorithms. Once atrial fibrillation has been detected, the operational circuitry will then provide QRS synchronized atrial defibrillation/cardioversion using the same shock energy and waveshape characteristics used for ventricular defibrillation/cardioversion.
In addition to use of the sense circuitry for detection of V-Fib or V-Tach by examining the QRS waves, the sense circuitry can check for the presence or the absence of respiration. The respiration rate can be detected by monitoring the impedance across the thorax using subthreshold currents delivered across the active canister and the high voltage subcutaneous lead electrode and monitoring the frequency in undulation in the waveform that results from the undulations of transthoracic impedance during the respiratory cycle. If there is no undulation, then the patient is not respiring and this lack of respiration can be used to confirm the QRS findings of cardiac arrest. The same technique can be used to provide information about the respiratory rate or estimate cardiac output as described in U.S. Pat. Nos. 6,095,987, 5,423,326, 4,450,527, the entire disclosures of which are incorporated herein by reference.
The most distal electrode on the composite subcutaneous electrode is a coil electrode 27 that is used for delivering the high voltage cardioversion/defibrillation energy across the heart. The coil cardioversion/defibrillation electrode is about 5-10 cm in length. Proximal to the coil electrode are two sense electrodes, a first sense electrode 25 is located proximally to the coil electrode and a second sense electrode 23 is located proximally to the first sense electrode. The sense electrodes are spaced far enough apart to be able to have good QRS detection. This spacing can range from 1 to 10 cm with 4 cm being presently preferred. The electrodes may or may not be circumferential with the preferred embodiment. Having the electrodes non-circumferential and positioned outward, toward the skin surface, is a means to minimize muscle artifact and enhance QRS signal quality. The sensing electrodes are electrically isolated from the cardioversion/defibrillation electrode via insulating areas 29. Similar types of cardioversion/defibrillation electrodes are currently commercially available in a transvenous configuration. For example, U.S. Pat. No. 5,534,022, the entire disclosure of which is herein incorporated by reference, discloses a composite electrode with a coil cardioversion/defibrillation electrode and sense electrodes. Modifications to this arrangement are contemplated within the scope of the invention. One such modification is illustrated in FIG. 2 where the two sensing electrodes 25 and 23 are non-circumferential sensing electrodes and one is located at the distal end, the other is located proximal thereto with the coil electrode located in between the two sensing electrodes. In this embodiment the sense electrodes are spaced about 6 to about 12 cm apart depending on the length of the coil electrode used. FIG. 3 illustrates yet a further embodiment where the two sensing electrodes are located at the distal end to the composite electrode with the coil electrode located proximally thereto. Other possibilities exist and are contemplated within the present invention. For example, having only one sensing electrode, either proximal or distal to the coil cardioversion/defibrillation electrode with the coil serving as both a sensing electrode and a cardioversion/defibrillation electrode.
The active canister housing will provide energy and voltage intermediate to that available with ICDs and most AEDs. The typical maximum voltage necessary for ICDs using most biphasic waveforms is approximately 750 Volts with an associated maximum energy of approximately 40 Joules. The typical maximum voltage necessary for AEDs is approximately 2000-5000 Volts with an associated maximum energy of approximately 200-360 Joules depending upon the model and waveform used. The S-ICD and the US-ICD of the present invention uses maximum voltages in the range of about 50 to about 3500 Volts and is associated with energies of about 0.5 to about 350 Joules. The capacitance of the devices can range from about 25 to about 200 micro farads.
FIG. 5 illustrates a different placement of the present invention. The S-ICD canister with the active housing is located in the left posterior axillary line approximately lateral to the tip of the inferior portion of the scapula. This location is especially useful in children. The lead 21 of the subcutaneous electrode traverses in a subcutaneous path around the thorax terminating with its distal electrode end at the anterior precordial region, ideally in the inframammary crease. FIG. 6 illustrates the embodiment of FIG. 1 subcutaneously implanted in the thorax with the proximal sense electrodes 23 and 25 located at approximately the left axillary line with the cardioversion/defibrillation electrode just lateral to the tip of the inferior portion of the scapula.
FIG. 7 schematically illustrates the method for implanting the S-ICD of the present invention. An incision 31 is made in the left anterior axillary line approximately at the level of the cardiac apex. This incision location is distinct from that chosen for S-ICD placement and is selected specifically to allow both canister location more medially in the left inframammary crease and lead positioning more posteriorly via the introducer set (described below) around to the left posterior axillary line lateral to the left scapula. That said, the incision can be anywhere on the thorax deemed reasonably by the implanting physician although in the preferred embodiment, the S-ICD of the present invention will be applied in this region. A subcutaneous pathway 33 is then created medially to the inframammary crease for the canister and posteriorly to the left posterior axillary line lateral to the left scapula for the lead.
FIGS. 10 and 11 illustrate another embodiment of the present S-lCD invention. In this embodiment there are two subcutaneous electrodes 13 and 13′ of opposite polarity to the canister. The additional subcutaneous electrode 13′ is essentially identical to the previously described electrode. In this embodiment the cardioversion/defibrillation energy is delivered between the active surface of the canister and the two coil electrodes 27 and 27′. Additionally, provided in the canister is means for selecting the optimum sensing arrangement between the four sense electrodes 23, 23′, 25, and 25′. The two electrodes are subcutaneously placed on the same side of the heart. As illustrated in FIG. 11, one subcutaneous electrode 13 is placed inferiorly and the other electrode 13′ is placed superiorly. It is also contemplated with this dual subcutaneous electrode system that the canister and one subcutaneous electrode are the same polarity and the other subcutaneous electrode is the opposite polarity.
The circuitry of this canister is similar to the circuitry described above. Additionally, the canister can optionally have at least one sense electrode located on either the active surface or the inactive surface and the circuitry within the canister can be programmable as described above to allow for the selection of the best sense electrodes. It is presently preferred that the canister have two sense electrodes 26 and 28 located on the inactive surface of the canisters as illustrated, where the electrodes are spaced from about 1 to about 10 cm apart with a spacing of about 3 cm being presently preferred. However, the sense electrodes can be located on the active surface as described above.
FIGS. 14 to 18 depict particular US-ICD embodiments of the present invention. The various sensing, shocking and pacing circuitry, described in detail above with respect to the S-ICD embodiments, may additionally be incorporated into the following US-ICD embodiments. Furthermore, particular aspects of any individual S-ICD embodiment discussed above may be incorporated, in whole or in part, into the US-ICD embodiments depicted in the following figures.
Turning now to FIG. 14, the US-ICD of the present invention is illustrated. The US-ICD consists of a curved housing 1211 with a first and second end. The first end 1413 is thicker than the second end 1215. This thicker area houses a battery supply, capacitor and operational circuitry for the US-ICD. The circuitry will be able to monitor cardiac rhythms for tachycardia and fibrillation, and if detected, will initiate charging the capacitor and then delivering cardioversion/defibrillation energy through the two cardioversion/defibrillating electrodes 1417 and 1219 located on the outer surface of the two ends of the housing. The circuitry can provide cardioversion/defibrillation energy in different types of waveforms. In one embodiment, a 100 uF biphasic waveform is used of approximately 10-20 ms total duration and with the initial phase containing approximately ⅔ of the energy, however, any type of waveform can be utilized such as monophasic, biphasic, multiphasic or alternative waveforms as is known in the art.
The two cardioversion/defibrillation electrodes on the housing are used for delivering the high voltage cardioversion/defibrillation energy across the heart. In the preferred embodiment, the cardioversion/defibrillation electrodes are coil electrodes, however, other cardioversion/defibrillation electrodes could be used such as having electrically isolated active surfaces or platinum alloy electrodes. The coil cardioversion/defibrillation electrodes are about 5-10 cm in length. Located on the housing between the two cardioversion/defibrillation electrodes are two sense electrodes 1425 and 1427. The sense electrodes are spaced far enough apart to be able to have good QRS detection. This spacing can range from 1 to 10 cm with 4 cm being presently preferred. The electrodes may or may not be circumferential with the preferred embodiment. Having the electrodes non-circumferential and positioned outward, toward the skin surface, is a means to minimize muscle artifact and enhance QRS signal quality. The sensing electrodes are electrically isolated from the cardioversion/defibrillation electrode via insulating areas 1423. Analogous types of cardioversion/defibrillation electrodes are currently commercially available in a transvenous configuration. For example, U.S. Pat. No. 5,534,022, the entire disclosure of which is herein incorporated by reference, discloses a composite electrode with a coil cardioversion/defibrillation electrode and sense electrodes. Modifications to this arrangement are contemplated within the scope of the invention. One such modification is to have the sense electrodes at the two ends of the housing and have the cardioversion/defibrillation electrodes located in between the sense electrodes. Another modification is to have three or more sense electrodes spaced throughout the housing and allow for the selection of the two best sensing electrodes. If three or more sensing electrodes are used, then the ability to change which electrodes are used for sensing would be a programmable feature of the US-ICD to adapt to changes in the patient physiology and size over time. The programming could be done via the use of physical switches on the canister, or as presently preferred, via the use of a programming wand or via a wireless connection to program the circuitry within the canister.
The S-ICD and US-ICD, in alternative embodiments, have the ability to detect and treat atrial rhythm disorders, including atrial fibrillation. The S-ICD and US-ICD have two or more electrodes that provide a far-field view of cardiac electrical activity that includes the ability to record the P-wave of the electrocardiogram as well as the QRS. One can detect the onset and offset of atrial fibrillation by referencing to the P-wave recorded during normal sinus rhythm and monitoring for its change in rate, morphology, amplitude and frequency content. For example, a well-defined P-wave that abruptly disappeared and was replaced by a low-amplitude, variable morphology signal would be a strong indication of the absence of sinus rhythm and the onset of atrial fibrillation. In an alternative embodiment of a detection algorithm, the ventricular detection rate could be monitored for stability of the R-R coupling interval. In the examination of the R-R interval sequence, atrial fibrillation can be recognized by providing a near constant irregularly irregular coupling interval on a beat-by-beat basis. A R-R interval plot during AF appears �cloudlike� in appearance when several hundred or thousands of R-R intervals are plotted over time when compared to sinus rhythm or other supraventricular arrhythmias. Moreover, a distinguishing feature compared to other rhythms that are irregularly irregular, is that the QRS morphology is similar on a beat-by-beat basis despite the irregularity in the R-R coupling interval. This is a distinguishing feature of atrial fibrillation compared to ventricular fibrillation where the QRS morphology varies on a beat-by-beat basis. In yet another embodiment, atrial fibrillation may be detected by seeking to compare the timing and amplitude relationship of the detected P-wave of the electrocardiogram to the detected QRS (R-wave) of the electrocardiogram. Normal sinus rhythm has a fixed relationship that can be placed into a template matching algorithm that can be used as a reference point should the relationship change.
Once atrial fibrillation is detected, the arrhythmia can be treated by delivery of a synchronized shock using energy levels up to the maximum output of the device therapy for terminating atrial fibrillation or for other supraventricular arrhythmias. The S-ICD or US-ICD electrode system can be used to treat both atrial and ventricular arrhythmias not only with shock therapy but also with pacing therapy. In a further embodiment of the treatment of atrial fibrillation or other atrial arrhythmias, one may be able to use different electrode systems than what is used to treat ventricular arrhythmias. Another embodiment would be to allow for different types of therapies (amplitude, waveform, capacitance, etc.) for atrial arrhythmias compared to ventricular arrhythmias.
FIGS. 19-26 refer generally to alternative S-ICD/US-ICD canister embodiments. Although the following canister designs, various material constructions, dimensions and curvatures discussed in detail below may be incorporated into either S-ICD or US-ICD canister embodiments, hereinafter these attributes will be discussed solely with respect to S-ICDs.
The canisters illustrated in these Figures possess a configuration that may 1) aid in the initial canister implantation; 2) restrict canister displacement once properly positioned; 3) create a consistently focused array of energy delivered toward the recipient's heart with less disbursement to other areas of the thorax; 4) allow for good signal reception from the heart by an S-ICD system; or 5) provide significant comfort and long-term wearability in a broad spectrum of patients with differing thoracic sizes and shapes. More particularly, FIGS. 19-26 detail various material constructions, dimensions and curvatures that are incorporated within the numerous S-ICD canister designs detailed in FIGS. 19-26C.
The S-ICD devices of the present invention provide an energy (electric field strength (V/cm), current density (A/cm2), voltage gradient (V/cm) or other measured unit of energy) to a patient's heart. S-ICD devices of the present invention will generally use voltages in the range of 700 V to 3150 V, requiring energies of approximately 40 J to 210 J. These energy requirements will vary, however, depending upon the form of treatment, the proximity of the canister from the patient's heart, the relative relationship of the S-ICD canister's electrode to the lead electrode, the nature of the patient's underlying heart disease, the specific cardiac disorder being treated, and the ability to overcome diversion of the S-ICD electrical output into other thoracic tissues.
Ideally, the emitted energy from the S-ICD device will be directed into the patient's anterior mediastinum, through the majority of the heart, and out to the coupled lead electrode positioned in the posterior, posterolateral and/or lateral thoracic locations. Furthermore, it is desirable that the S-ICD canister 190 be capable of delivering this directed energy, as a general rule, at an adequate effective field strength of about 3-5 V/cm to approximately 90 percent of a patient's ventricular myocardium using a biphasic waveform. This delivered effective field strength should be adequate for defibrillation of the patient's heart�an intended application of an embodiment of the present invention.
Compliant canister housings 192 often provide increased comfort when implanted in patient recipients. S-ICD canisters 190 formed from such materials permit limited, but significant, deflection of the canister housing 192 with certain thoracic motions. Examples of permitted deflections are ones that are applied to the canister housing 192 by surrounding muscle tissue. The use of a compliant canister housing is particularly beneficial in canister housing 192 embodiments that extend over a significant portion of a patient's thorax. For example, a compliant canister housing 192 is particularly beneficial in US-ICD devices.
FIG. 27 illustrates a US-ICD canister housing embodiment 310 comprising, in part, of a compliant material. The US-ICD canister housing 310 includes a first end 312 and a second end 314. As described in detail above, US-ICD canister housing 310 further comprise a plurality of electrodes contained on the canister housing 310. In particular embodiments, and as depicted in FIG. 27, two electrodes are used, a first electrode 316 and a second electrode 318 (shown in phantom). In this embodiment, the two electrodes 316 and 318 are positioned at each end 312 and 314 of the US-ICD canister housing 310. Additionally, a connecting member 320 is positioned between the two ends 312 and 314 of the canister housing 310 to join the canister housing's two ends and encase the US-ICD's electronic circuitry. In this particular embodiment, a compliant or otherwise pliable material is used to form the connecting member 320.
The length of the US-ICD canister housing 310 allows the single unitary device to correctly position the electrodes 316 and 318 within the patient to form a depolarization vector (described in detail below) with respect to the patient's heart. To accommodate the individual body shape of the patient recipient, however, embodiments of the present invention utilize compliant materials to adjust the positioning of the US-ICD device to obtain this proper depolarization vector. The compliant materials used in these embodiments may comprise a portion of the US-ICD canister housing 310, or alternatively, may comprise the canister housing 310 in its entirety.
Compliant materials suitable for the S-ICD canister housings 192 (and US-ICD canister housings 310) of the present invention include polyurethanes, polyamides, polyetheretherketones (PEEK), polyether block amides (PEBA), polytetrafluoroethylene (PTFE), polyethylene, silicones, and mixtures thereof.
The use of compliant materials allows the US-ICD depicted in FIG. 27 to bend and conform specifically to an individual's ribcage. Thus, the use of compliant materials permits the proper sizing of the US-ICD canister housing 310 to numerous patients, without requiring the manufacturer to generate numerous canister housings 310 of various specific shapes and sizes. Moreover, the correct material selection (or combination thereof) for the US-ICD device is helpful in eliminating patient awareness of the device and in improving the long-term wearability of the implanted device.
The size of the electrically conductive surface of an electrode 204, in one particular embodiment, is approximately 500 square millimeters in area. In alternate embodiments, it is desirable to maintain the size of the electrically conductive surface between approximately 100 square millimeters and approximately 2000 square millimeters in area. As with the size of the canister housing 192, the size of the electrically conductive surface may vary to accommodate the particular patient recipient. Furthermore, the shape and size of an electrode 204 may vary to accommodate the placement of the electrode 204 on the canister housing 192. The shape and size of an electrode may also be varied to adapt to specified diagnostic and therapeutic functions performed by the canister 190. For example, the electrode's 204 size and shape may be altered to minimize energy loss to surrounding bodily tissues, or for minimizing the diversion of current away from the heart.
As discussed above, electrodes 204 may vary in shape and size to accommodate an assortment of canister housing 192 designs. For illustrative purposes, FIG. 20 and FIGS. 23A-25A show various electrode shapes disposed upon various canister housings 192. The canister housings 192 depicted in these figures, however, are not limited to the electrode shape specifically illustrated.
Generally, it is desirable to have the electrode's longest conductive surface plane positioned perpendicular to the extending ribs within a recipient's rib cage. Aligning the electrode 204 in this manner removes the longest conductive plane from possibly extending directly over any one particular rib. If the longest conductive surface were to extend along the length of a rib, a greater percentage of emitted energy would be distributed through the rib material, and consequently, may fail to reach the heart muscle. When aligned perpendicular to the ribs, only a portion of the conductive surface is directly over any particular rib. This alignment permits only a small percentage of the emitted energy to be obstructed by the impeding rib material. Therefore, in particular S-ICD canister 190 embodiments that extend parallel with a recipient's rib cage, the width 205 of the electrode's conductive surface is approximately greater than or equal to the length 207 of the electrode's conductive surface. This electrode 204 sizing is best illustrated with reference to FIG. 20. The conductive surface of the thumbnail-shaped electrode in FIG. 20 is depicted as both shallow and wide. In contrast, S-ICD canister 190 embodiments that extend perpendicular with a recipient's rib cage can have their conductive surface's length 207 being greater than their conductive surface's width 205. The appropriate S-ICD canister 190 alignment, and subsequently the appropriate electrode 204 alignment, is determined by the style of S-ICD canister 190 chosen for the patient recipient. FIGS. 23A-26C illustrate numerous S-ICD canister housing embodiments 192 for properly positioning an electrode 204 over a recipient's heart. The embodiments depicted, however, are for illustrative purposes only, and are not intended to limit the scope of the present invention.
The depth of the canister housing 192 is shown as being very narrow as to the canister housing's length 207. The canister's housing depth is less than approximately 15 millimeters. In alternate embodiments, the depth of the canister's housing depth is approximately 5 millimeters to approximately 10 millimeters. At the tapered distal end 200, the canister housing may have a depth of approximately 1-4 millimeters.
In particular embodiments, a physician advances both the S-ICD canister 190 and the lead electrode 191 within the patient to form a depolarization vector with respect to the patient's heart 218. The depolarization vector is a vector having an origin, a first end point and a second end point.
In order to obtain the desired degree of separation for the depolarization vector, generally one device (either the S-ICD canister 190 or the lead electrode 191) must be advanced anteriorly while the other device is advanced posteriorly from the initial incision 210. Accordingly, when the S-ICD canister 190 is advanced subcutaneously and anteriorly from the incision 210, the lead electrode 191 must be advanced subcutaneously and posteriorly from the incision 210. With this particular embodiment, a physician may advance the S-ICD canister 190 medially toward the patient's left inframammary crease to a location proximate the patient's sternum 212.
Alternatively, the physician may advance, and subsequently position the S-ICD canister 190 within the anterior portion of the patient's ribcage 216. This anterior placement may further include the patient's left parasternal region, an anterior placement within the region of the patient's third and the patient's twelfth rib 214, or generally any subcutaneous ribcage 216 placement anterior to the patient's heart 218. In order to complement the S-ICD canister's 190 placement, and obtain the correct depolarization vector, the lead electrode 191 must be advanced posteriorly toward the paraspinal or parascapular region of the patient's ribcage 216.
In alternative embodiments, the origin 199 of the curvature vector θ may originate at a point other than the center of the S-ICD canister 190. Origins 199 shifted from the center of the S-ICD canister 190 produce regions of greater curvature, as well as areas of lesser curvature, in the same S-ICD canister 190. Similarly, a S-ICD canister 190 may possess multiple curvature vectors θ having origins 199 throughout the length of the S-ICD canister 190. Multiple curvature vectors θ produce various non-linear or nonsymmetrical curves that, in certain circumstances, remain generally arc-shaped. Canister housings possessing multiple curvature vectors θ are particularly suitable for S-ICD canister 190 placement near the patient's sides (generally in the area under the patient's arms where the thorax has a more marked degree of curvature). Canister housings 192 incorporating a nonsymmetrical curvature are generally longer S-ICD canisters 190 that span over the front and sides of the patient's ribcage. In particular, these S-ICD canisters 190 span areas of the ribcage 216 that are generally planar (around the patient's sternum 212), as well as areas that are highly curved (generally in the area under the patient's arms).
FIGS. 23A-26C depict particular S-ICD canister 190 designs. In each of these particular S-ICD canister designs, the various material constructions, dimensions and curvatures, discussed in detail above, may be incorporated within each individual S-ICD canister design. Furthermore, particular aspects of any individual S-ICD canister design may be incorporated, in whole or in part, into another depicted S-ICD canister design.
Turning now to FIG. 23A, a S-ICD canister 220 having a duckbill-shaped canister housing 222 is shown. The duckbill-shaped canister housing 222 has a proximal end 226 and a distal end 234. The proximal end 226 of the duckbill-shaped canister housing 222 further includes a main housing member 228 and a distal housing member 230. The distal housing member 230 is an elongated segment extending distally from the distal end of the main housing member 228. Although the two segments differ in their size and shape, the distal housing member 230 and main housing member 228 are generally contiguously and fluidly attached to one another and may be formed from a single mold. In alternative embodiments, however, the distal housing member 230 may be hinged to the main housing member 228. The distal housing member 230 also generally comprises a material that is similar in composition to that forming the main housing member 228. In alternate embodiments, however, the distal housing member 230 may include a material that possesses enhanced electrically insulated characteristics.
The main housing member 228 generally encases the operational circuitry, batteries and capacitors of the duckbill-shaped S-ICD canister 220. The width and length of the main housing member 228 enable the main housing member 228 to accommodate batteries and capacitors for delivering a shocking energy of approximately 50 J of energy, 75 J of energy, 100 J of energy, 125 J of energy, 150 J of energy and 200 J of energy.
In certain embodiments of the present invention, an associated feature of the electrode 236 at the distal end is the presence of a margin of insulated material 237 around the active electrode 236. The margin of insulated material 237 may aid in directing emitted energy from the electrode 236 inwardly toward the patient's heart instead of dispersing energy outward toward the patient's chest wall. This margin of insulated material 237 typically ranges from 1-5 mm in width and may extend to the margin of the housing. Moreover, in certain embodiments, the margin of insulated material 237 comprises a ceramic material or other material designed to facilitate focusing of current inward toward the heart.
In certain embodiments of the present invention, the electronic components (e.g., circuitry, batteries and capacitors) of the S-ICD canister 220 are generally absent from the distal housing member 230. As such, the depth of the distal housing member 230 may be greatly reduced. In these embodiments, a depth of approximately 1 millimeter may be obtained at the distal head 234 of the duckbill-shaped S-ICD canister 220.
FIG. 25A depicts yet another embodiment of a S-ICD canister having a �tongue depressor-shaped� canister housing 260. The tongue depressor-shaped canister housing 260 includes a top surface 261, a bottom surface (not shown) and surrounding sides 262 connecting these two surfaces. The tongue depressor-shaped canister housing 260 further includes a distal end 264 and a proximal end 266. The distal end 264 and the proximal end 266 of the tongue depressor-shaped canister housing 260, however, are rounded. In one embodiment, the rounded ends extend outwardly away from the canister housing 260 in either the corresponding distal or proximal direction. The rounded ends generally are circular arc-shaped curves. However, the rounded ends may also be elliptical or nonsymmetrical arc-shaped curves.
FIGS. 26A-26C illustrate another embodiment of a S-ICD canister having a multi-segment canister housing 280. The multi-segment canister housing 280 includes at least two canister housing segments that are coupled together. The S-ICD canister depicted in FIG. 26A, 26B and 26C specifically have a distal segment 282 and a proximal segment 284 hinged, or otherwise coupled, together.
FIG. 28A illustrate another embodiment of an S-ICD canister having a multi-segment canister housing 330. The multi-segment canister housing 330 includes at least two canister housing segments that are coupled together. The S-ICD canister depicted in FIG. 28A specifically include a distal segment 332 and a proximal segment 334 coupled together. The coupling of adjacent segments occurs through a hinging mechanism. As illustrated in FIG. 28A, a first hinging mechanism 336 and a second hinging mechanism 338 are positioned between the proximal segment 334 and the distal segment 332 of the multi-segment canister housing 330. Although two hinging mechanisms 336 and 338 are specifically depicted, any number of hinging mechanisms may be utilized in coupling adjacent segments. Moreover, the hinging mechanisms may be positioned at any suitable location on the canister housing 330 that enables adjacent segments to pivot about the hinging mechanism.
FIG. 28B generally depicts one embodiment of the present invention for hinging the proximal end 334 of the multi-segment canister 330 to the distal segment 332 of the multi-segment canister 330. More specifically, FIG. 28B illustrates the first hinging mechanism 336 of FIG. 28A.
As shown, the proximal segment 334 includes a threaded hole 340 that traverses through the entire depth of the proximal segment's canister housing 334. The distal segment 332, in contrast, includes a threaded ball 342 (a ball having a single orifice that is threaded) retained by a plurality of leaf springs 344. The leaf springs 344 in the distal segment 332 prevent the displacement of the threaded ball 342 from the distal segment 332, while permitting rotational movement of the threaded ball 342. In certain embodiments of the present invention, four leaf springs 344 are utilized to apply a positive pressure against the threaded ball 342.
The coupling of the proximal segment 334 with the distal segment 332 occurs by advancing a screw 346 through the threaded hole 340 of the proximal segment 334 and into the threaded ball 342 held within the distal segment 332. The length of the screw 346 enables a portion of the screw 346 to be retained within both the proximal segment 334 and the distal segment 332 of the multi-segment canister housing 330. As such, the two segments permit some pivoting action between the segments while remaining positively coupled together. Moreover, the screw 346 may further act as a conduit for the transfer of electrical energy between segments. Electrical energy may be transferred from an electrical circuit in one segment, through the screw 346, and into an adjacent segment.
The use of a threaded ball 342 enables a degree of rotational freedom between the two segments. The segments, therefore, may be translated in numerous directions with respect to one another. This added freedom permits the multi-segment canister housing 340 to conform to an array of shapes, and subsequently, to an array of patient recipient body types.
FIG. 29A is a bottom plan view of an alternative S-ICD canister 350 of the present invention having a canister housing region that is pliable. The pliable region of the canister housing 350 comprises a plurality of pleats 352 in the material forming the canister housing 350. In particular embodiments, materials forming the pleated sections 354 of the canister housing 350 include polymeric materials such as polyurethanes, polyamides, polyetheretherketones (PEEK), polyether block amides (PEBA), polytetrafluoroethylene (PTFE), polyethylenes, silicones, and mixtures thereof. Metallic materials suitable for the pleated sections 354 of the canister housing 350 include stainless steel, and titanium. Alloys suitable for the pleated sections 354 of the canister housing 350 include stainless steel alloys and titanium alloys such as nickel titanium.
FIG. 29B is a side view of the S-ICD canister embodiment of FIG. 29A. As depicted, the individual pleats 352 in the pleated section 354 may uniformly expand or contract; enabling the canister housing 350 to either increase or decrease its overall length. Moreover, individual pleats 352 may expand in one region and contract in another to allow the canister housing 350 to bend either inwardly or outwardly. For example, the pleats 352 may expand along the top surface 356 of the canister housing 350 while contract along the bottom surface 358 of the canister housing 350 to enable the canister housing 350 to reduce the degree of separation in the canister housing's curvature vector θ (described in detail above).
The use of a pleated section 354 in a canister housing 350 allows the S-ICD/US-ICD to bend and conform specifically to an individual's ribcage. Thus, the use of a pleated section 354 permits the proper sizing of a single canister housing 350 in numerous patients, without requiring the manufacturer to generate numerous canister housings of various specific shapes and sizes. Moreover, the use of pleated canister housings 350 is helpful in eliminating patient awareness of the implanted device and in improving the long-term wearability of the implanted device.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS3653387May 8, 1970Apr 4, 1972Cardiac Electronics IncProtector circuit for cardiac apparatusUS3710374Aug 17, 1970Jan 9, 1973Wester Instr IncDual-slope and analog-to-digital converter wherein two analog input signals are selectively integrated with respect to timeUS3911925May 23, 1974Oct 14, 1975Tillery Jr Joe BEar trimming forcepsUS4157720Sep 16, 1977Jun 12, 1979Greatbatch WCardiac pacemakerUS4191942Jun 8, 1978Mar 4, 1980National Semiconductor CorporationSingle slope A/D converter with sample and holdUS4223678May 3, 1978Sep 23, 1980Mieczyslaw MirowskiArrhythmia recorder for use with an implantable defibrillatorUS4248237Mar 9, 1978Feb 3, 1981Needle Industries LimitedCardiac pacemakersUS4291707Apr 30, 1979Sep 29, 1981Mieczyslaw MirowskiImplantable cardiac defibrillating electrodeUS4314095Apr 30, 1979Feb 2, 1982Mieczyslaw MirowskiDevice and method for making electrical contactUS4402322Mar 25, 1981Sep 6, 1983Medtronic, Inc.Pacer output circuitUS4407288Mar 16, 1981Oct 4, 1983Mieczyslaw MirowskiImplantable heart stimulator and stimulation methodUS4424818Feb 18, 1982Jan 10, 1984Medtronic, Inc.Electrical lead and insertion toolUS4450527Jun 29, 1982May 22, 1984Bomed Medical Mfg. Ltd.Noninvasive continuous cardiac output monitorUS4567900Jun 4, 1984Feb 4, 1986Moore J PaulInternal deployable defibrillator electrodeUS4602637Jan 11, 1984Jul 29, 1986Siemens AktiengesellschaftHeart pacemaker systemUS4603705May 4, 1984Aug 5, 1986Mieczyslaw MirowskiIntravascular multiple electrode unitary catheterUS4693253Mar 23, 1981Sep 15, 1987Medtronic, Inc.Automatic implantable defibrillator and pacerUS4765341Aug 25, 1983Aug 23, 1988Mieczyslaw MirowskiCardiac electrode with attachment finUS4800883Apr 2, 1986Jan 31, 1989Intermedics, Inc.Apparatus for generating multiphasic defibrillation pulse waveformUS4830005Jul 23, 1987May 16, 1989Siemens-Pacesetter, Inc.Disposable in-package load test element for pacemakersUS4944300Jan 12, 1990Jul 31, 1990Sanjeev SaksenaMethod for high energy defibrillation of ventricular fibrillation in humans without a thoracotomyUS5105810Jul 24, 1990Apr 21, 1992Telectronics Pacing Systems, Inc.Implantable automatic and haemodynamically responsive cardioverting/defibrillating pacemaker with means for minimizing bradycardia support pacing voltagesUS5109842Sep 24, 1990May 5, 1992Siemens Pacesetter, Inc.Implantable tachyarrhythmia control system having a patch electrode with an integrated cardiac activity systemUS5129392Dec 20, 1990Jul 14, 1992Medtronic, Inc.Apparatus for automatically inducing fibrillationUS5133353Apr 25, 1990Jul 28, 1992Cardiac Pacemakers, Inc.Implantable intravenous cardiac stimulation system with pulse generator housing serving as optional additional electrodeUS5144946Aug 5, 1991Sep 8, 1992Siemens Pacesetter, Inc.Combined pacemaker substrate and electrical interconnect and method of assemblyUS5184616Oct 21, 1991Feb 9, 1993Telectronics Pacing Systems, Inc.Apparatus and method for generation of varying waveforms in arrhythmia control systemUS5191901Aug 29, 1991Mar 9, 1993Mieczyslaw MirowskiControlled discharge defibrillation electrodeUS5203348Jun 6, 1990Apr 20, 1993Cardiac Pacemakers, Inc.Body implantable tissue stimulating electrode assemblyUS5230337Jul 14, 1992Jul 27, 1993Cardiac Pacemakers, Inc.Process for implanting subcutaneous defibrillation electrodesUS5255692Sep 4, 1992Oct 26, 1993Siemens AktiengesellschaftSubcostal patch electrodeUS5261400Feb 12, 1992Nov 16, 1993Medtronic, Inc.A human heartUS5292338Jul 30, 1992Mar 8, 1994Medtronic, Inc.Atrial defibrillator employing transvenous and subcutaneous electrodes and method of useUS5300106Jun 7, 1991Apr 5, 1994Cardiac Pacemakers, Inc.Insertion and tunneling tool for a subcutaneous wire patch electrodeUS5331966Dec 16, 1993Jul 26, 1994Medtronic, Inc.Subcutaneous multi-electrode sensing system, method and pacerUS5342407Jul 13, 1992Aug 30, 1994Cardiac Pacemakers, Inc.Body implantable defibrillation systemUS5366496Apr 1, 1993Nov 22, 1994Cardiac Pacemakers, Inc.Subcutaneous shunted coil electrodeUS5376103Mar 19, 1992Dec 27, 1994Angeion CorporationElectrode system for implantable defibrillatorUS5376104Feb 2, 1993Dec 27, 1994Nihon Kohden CorporationDefibrillator with electrocardiogram monitorUS5385574Jul 24, 1992Jan 31, 1995Cardiac Pacemakers, Inc.Implantable intravenous cardiac stimulation system with pulse generator housing serving as optional additional electrodeUS5391200Mar 10, 1994Feb 21, 1995Cardiac Pacemakers, Inc.Defibrillation patch electrode having conductor-free resilient zone for minimally invasive deploymentUS5405363Jun 21, 1994Apr 11, 1995Angelon CorporationImplantable cardioverter defibrillator having a smaller displacement volumeUS5411539Aug 31, 1993May 2, 1995Medtronic, Inc.Active can emulator and method of useUS5411547Aug 9, 1993May 2, 1995Pacesetter, Inc.Implantable cardioversion-defibrillation patch electrodes having means for passive multiplexing of discharge pulsesUS5413591Jul 22, 1993May 9, 1995Angeion CorporationCurrent truncated waveform defibrillatorUS5423326May 14, 1993Jun 13, 1995Drexel UniversityApparatus and method for measuring cardiac outputUS5447521Oct 12, 1994Sep 5, 1995Angeion CorporationSafety system for an implantable defibrillatorUS5470345Jun 16, 1994Nov 28, 1995Medtronic, Inc.For the outer packaging of an implantable medical deviceUS5476503Mar 28, 1994Dec 19, 1995Pacesetter, Inc.Sense array intelligent patch lead for an implantable defibrillator and methodUS5509923Dec 21, 1990Apr 23, 1996Raychem CorporationDevice for dissecting, grasping, or cutting an objectUS5509928Mar 2, 1995Apr 23, 1996Pacesetter, Inc.Internally supported self-sealing septumUS5531765Jul 15, 1994Jul 2, 1996Ventritex, Inc.Method and apparatus for producing configurable biphasic defibrillation waveformsUS5531766Jan 23, 1995Jul 2, 1996Angeion CorporationImplantable cardioverter defibrillator pulse generator kite-tail electrode systemUS5534019Dec 9, 1994Jul 9, 1996Ventritex, Inc.Cardiac defibrillator with case that can be electrically active or inactiveUS5534022Nov 22, 1994Jul 9, 1996Ventritex, Inc.Lead having an integrated defibrillation/sensing electrodeUS5597956Aug 18, 1995Jan 28, 1997Murata Manufacturing Co., Ltd.Of an electrostatic servo systemUS5601607Jan 23, 1995Feb 11, 1997Angeion CorporationImplantable cardioverter defibrillator housing plated electrodeUS5603732Nov 6, 1995Feb 18, 1997Cardiac Pacemakers, Inc.Subcutaneous defibrillation electrodesUS5618287Mar 17, 1995Apr 8, 1997Thomas J. FogartyMethods of surgically implanting a defibrillator electrode within a patientUS5620477May 31, 1995Apr 15, 1997Ventritex, Inc.Pulse generator with case that can be active or inactiveUS5643328Jul 19, 1996Jul 1, 1997Sulzer Intermedics Inc.Implantable cardiac stimulation device with warning system having elongated stimulation electrodeUS5645586Jul 8, 1994Jul 8, 1997Ventritex, Inc.Conforming implantable defibrillatorUS5658317Aug 14, 1995Aug 19, 1997Cardiac Pacemakers, Inc.Threshold templating for digital AGCUS5658321Jun 9, 1995Aug 19, 1997Ventritex, Inc.Conductive housing for implantable cardiac deviceUS5674260Feb 23, 1996Oct 7, 1997Pacesetter, Inc.Apparatus and method for mounting an activity sensor or other component within a pacemaker using a contoured hybrid lidUS5690648Mar 22, 1996Nov 25, 1997Thomas J. FogartyMethods and apparatus for rolling a defibrillator electrodeUS5690683Jun 19, 1995Nov 25, 1997Cardiac Pacemakers, Inc.After potential removal in cardiac rhythm management deviceUS5697953Jan 11, 1996Dec 16, 1997Angeion CorporationImplantable cardioverter defibrillator having a smaller displacement volumeUS5713926Jan 30, 1995Feb 3, 1998Cardiac Pacemakers, Inc.Implantable intravenous cardiac stimulation system with pulse generator housing serving as optional additional electrodeUS5766226Dec 9, 1996Jun 16, 1998Angeion CorporationSwitched discharge pathways for ICD having multiple output capacitorsUS5776169Apr 28, 1997Jul 7, 1998Sulzer Intermedics Inc.Implantable cardiac stimulator for minimally invasive implantationUS5814090Nov 18, 1996Sep 29, 1998Angeion CorporationImplantable medical device having heat-shrink conforming shieldUS5836976Apr 30, 1997Nov 17, 1998Medtronic, Inc.Cardioversion energy reduction systemUS5895414Apr 10, 1997Apr 20, 1999Sanchez-Zambrano; SergioPacemaker housingUS5919211Jun 27, 1997Jul 6, 1999Adams; Theodore P.ICD power source using multiple single use batteriesUS5919222Jan 6, 1998Jul 6, 1999Medtronic Inc.Adjustable medical electrode leadUS5925069Nov 7, 1997Jul 20, 1999Sulzer Intermedics Inc.Removing conformal insulative material from implantable medical device using excimer laserUS5935154Dec 8, 1997Aug 10, 1999Cardiac Pacemakers, Inc.Implantable tissue stimulator incorporating deposited multilayer capacitorUS5941904Sep 12, 1997Aug 24, 1999Sulzer Intermedics Inc.Electromagnetic acceleration transducer for implantable medical deviceUS6014586Feb 27, 1997Jan 11, 2000Pacesetter, Inc.Vertically integrated semiconductor package for an implantable medical deviceUS6026325Jun 18, 1998Feb 15, 2000Pacesetter, Inc.Implantable medical device having an improved packaging system and method for making electrical connectionsUS6058328Jan 24, 1997May 2, 2000Pacesetter, Inc.Implantable stimulation device having means for operating in a preemptive pacing mode to prevent tachyarrhythmias and method thereofUS6093173Sep 9, 1998Jul 25, 2000Embol-X, Inc.Introducer/dilator with balloon protection and methods of useUS6095987Sep 19, 1997Aug 1, 2000Imagyn Medical Techonologies California, Inc.Apparatus and methods of bioelectrical impedance analysis of blood flowUS6128531Apr 1, 1998Oct 3, 2000Pacesetter, Inc.Delivery of ICD shock capacitor energy via a controlled current sourceUS6144866Oct 30, 1998Nov 7, 2000Medtronic, Inc.Multiple sensor assembly for medical electric leadUS6176879Dec 11, 1998Jan 23, 2001Implex Aktienegesellschaft Hearing TechnologyMedical implantUS6185450Jan 26, 1998Feb 6, 2001Physio-Control Manufacturing CorporationDigital sliding pole fast-restore for an electrocardiograph displayUS6411844Oct 19, 1999Jun 25, 2002Pacesetter, Inc.Fast recovery sensor amplifier circuit for implantable medical deviceUS6647292Sep 18, 2000Nov 11, 2003Cameron HealthUnitary subcutaneous only implantable cardioverter-defibrillator and optional pacerUS6721597Sep 18, 2000Apr 13, 2004Cameron Health, Inc.Subcutaneous only implantable cardioverter defibrillator and optional pacerUS7069075Nov 19, 2003Jun 27, 2006Medtronic, Inc.Subcutaneous implantable cardioverter/defibrillatorUS20010027330Jan 12, 2001Oct 4, 2001Physio-Control Manufacturing CorporationCircuit for performing external pacing and biphasic defibrillationUS20020042630Aug 27, 2001Apr 11, 2002Cameron Health, Inc.Canister designs for implantable cardioverter-defibrillatorsUS20050055056Nov 19, 2003Mar 10, 2005Olson Walter H.Subcutaneous implantable cardioverter/defibrillatorUS20060217770May 19, 2006Sep 28, 2006Olson Walter HSubcutaneous implantable cardioverter/defibrillatorUSH1905Mar 21, 1997Oct 3, 2000Medtronic, Inc.Mechanism for adjusting the exposed surface area and position of an electrode along a lead bodyDE29801807U1Feb 3, 1998Jun 4, 1998Mathar RalphVorrichtung zur Verwendung bei operativen Eingriffen, insbesondere bei BypassoperationenEP0095727A1May 26, 1983Dec 7, 1983Purdue Research FoundationMethod and apparatus for inserting a defibrillator electrode and defibrillator electrodeNon-Patent CitationsReference1Bardy, Gust H. et al., "Multicenter Experience with a Pectoral Unipolar Implantable Cardioverter-Defibrillator," JACC, Aug. 1996, vol. 28, No. 2, pp. 400-410.2Friedman, Richard A. et al., "Implantable Defibrillators In Children: From Whence to Shock," Journal of Cardiovascular Electrophysiology, vol. 12, No. 3, Mar. 2001, pp. 361-362.3Gradaus, Rainer et al., "Nonthoracotomy Implantable Cardioverter Defibrillator Placement in Children: Use of Subcutaneous Array Leads and Abdominally Placed Implantable Cardioverter Defibrillators in Children," Journal of Cardiovascular Electrophysiology, vol. 12, No. 3, Mar. 2001, pp. 356-360.4Higgins, Steven L. et al., "The First Year Experience with the Dual Chamber ICD," PACE, Jan. 2000, vol. 23, pp. 18-25.5Mirowski, M. et al., "Automatic Detection and Defibrillation of Lethal Arrhythmias-A New Concept," JAMA, vol. 213, No. 4, Jul. 27, 1970, pp. 615-616.6Olson, Walter H. et al., "Onset and Stability for Ventricular Tachyarrhythmia Detection in an Implantable Pacer-Cardioverter-Defribrillator," IEEE, (1987) pp. 167-170.7Schuder, John C. et al., "Experimental Ventricular Defibrillation with an Automatic and Completely Implanted System," Trans. Amer. Soc. Artif. Int. Organs, vol. XVI (1970) pp. 207-212.8Schuder, John C. et al., "Standby Implanted Defibrillators," Arch Intern. Med. vol. 127, Feb. 1971, p. 317 (single sheet).9Schuder, John C. et al., "Transthoracic Ventricular Defibrillation in the Dog with Truncated and Untruncated Exponential Stimuli," IEEE Transactions on Bio-Medical Engineering, vol. BME-18, No. 6, Nov. 1971, pp. 410-415.10Schuder, John C., "Completely Implantable Defibrillator," JAMA, vol. 214, No. 6, Nov. 9, 1970, p. 1123 (single sheet).11Schuder, John C., "The Role of an Engineering Oriented Medical Research Group in Developing Improved Methods and Devices for Achieving Ventricular Defibrillation: The University of Missouri Experience," PACE, vol. 16, Jan. 1993, pp. 95-124.12Schwacke, H. et al., "Komplikationen mit Sonden bei 340 Patienten mit einem Implantierbaren Kardioverter/Defibrillator," Z Kardiol (1999)vol. 88, No. 8, pp. 559-565.13Tietze U. et al., "Halbleiter-Schaltungstechnik," (C) Springer-Verlag (Berlin, Germany), (1991), pp. 784-786.14Valenzuela, Terrence D. et al., "Outcomes of Rapid Defibrillation by Security Officers After Cardiac Arrest in Casinos," The New England Journal of Medicine, Oct. 26, 2000, vol. 343, No. 17, pp. 1206-1209.15Walters, R.A. et al., "Analog to Digital Conversion Techniques in Implantable Devices," Annual International Conference of the IEEE Engineering in Medicine and Biology Society, vol. 13. No. 4 (1991) p. 1674-1676.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS8838234Mar 5, 2013Sep 16, 2014Cameron Health, Inc.Methods for implanting a subcutaneous defibrillatorUS20130023946 *Mar 20, 2012Jan 24, 2013Board Of Regents, The University Of TexasLow Power Apparatus and Method to Measure Complex Electrical Admittance or ImpedanceWO2012134891A1 *Mar 20, 2012Oct 4, 2012Admittance Technologies, Inc.Low power apparatus and method to measure complex electrical admittance or impedance* Cited by examinerClassifications U.S. Classification607/36, 607/5, 607/4International ClassificationA61N1/375, A61N1/39Cooperative ClassificationA61N1/3968, A61N1/375, A61N1/3956, A61N1/3756, A61N1/3975, A61N1/3906European ClassificationA61N1/39M, A61N1/375, A61N1/39NLegal EventsDateCodeEventDescriptionSep 23, 2011FPAYFee paymentYear of fee payment: 4RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services

value: This website is a search engine provided by Google. Handling over 3.5 billion searches per day, it has a 92% share of the global search engine market.


text:
Black Adjustable Bar Stools - Walmart.com
Electrode, Comp-888373859, DC-prod-az-southcentralus-15, ENV-prod-a, PROF-PROD, VER-20.0.17-EBF, SHA-4910456e606ca1d8e8baccbe01eef196e98107d2, CID-f78e02f8-32a-1712f239fbc809, Generated: Tue, 31 Mar 2020 05:49:56 GMT
AC Pacific Acme Furniture Amazing Choice Armen Living Avery Bella Vita Belleze Best Master Furniture BetterPosture Boraam Buff Bake Butler Specialty Company Carolina Classic Furniture Chintaly Imports Coaster Company CorLiving Costway Displays2go East End Imports Easyfashion FDW Flash Furniture Furniture of America Generic Hillsdale Furniture Jobri Joveco Ktaxon Legacy Décor Leopard Outdoor Leopard Outdoor Products Linon LumiSource Magshion Mainstays Mayakoba Modern Home Modway Monarch Muddy National Public Seating Noble House ONLINE Oakeskaran Offex Ore Porthos Home Powell Roundhill Furniture Safavieh Safco Signature Design by Ashley Silver Fox Simple Relax TMS TOV Furniture Trademark Global TygerClaw Uspridefurniture Vandue Corporation Vogue Furniture Direct WHI Winsome Yaheetech ZENY Zimtown Zuo Modern
Product TitleMainstays Benson Adjustable Height Swivel Barstool, ...
Product Title2pcs X-Large Bar Stools Adjustable Modern PU Leather ...
Current Price$75.00$75.00List Price$80.00$80.00
Electrode, Comp-28ce15fa-3c21-4ccd-a075-7615d6bb6c87, DC-scus-prod-a1, ENV-prod-m, PROF-PROD, VER-9.24.0, SHA-029f7be1826d3d1698d1d25afad11f1537a3b118, CID-6e4a0b27-007-1712f2c25f23e9, Generated: Tue, 31 Mar 2020 05:59:15 GMT

type: global

value: This website is an American multinational retail corporation that operates a chain of hypermarkets , discount department stores, and grocery stores from the United States, headquartered in Bentonville, Arkansas.