Cardiac Stimulation system
Some embodiments of pacing systems employ wireless electrode assemblies to provide pacing therapy. The wireless electrode assemblies may wirelessly receive energy via an inductive coupling so as to provide electrical stimulation to the surrounding heart tissue. In certain embodiments, the wireless electrode assembly may include one or more biased tines that shift from a first position to a second position to secure the wireless electrode assembly into the inner wall of the heart chamber.
Latest Boston Scientific Scimed, Inc. Patents:
This application claims priority to U.S. Provisional Application Ser. No. 60/748,964 filed on Dec. 9, 2005 and entitled “CARDIAC STIMULATION SYSTEM,” the contents of which are incorporated herein by reference.
TECHNICAL FIELDThis document relates to systems that electrically stimulate cardiac or other tissue.
BACKGROUNDPacing instruments can be used to treat patients suffering from a heart condition, such as a reduced ability to deliver sufficient amounts of blood from the heart. For example, some heart conditions may cause or be caused by conduction defects in the heart. These conduction defects may lead to irregular or ineffective heart contractions. Some pacing instruments (e.g., a pacemaker) may be implanted in a patient's body so that pacing electrodes in contact with the heart tissue provide electrical stimulation to regulate electrical conduction in the heart tissue. Such regulated electrical stimulation may cause the heart to contract and hence pump blood.
Conventionally, pacemakers include a pulse generator that is implanted, typically in a patient's pectoral region just under the skin. One or more wired leads extend from the pulse generator so as to contact various portions of the heart. An electrode at a distal end of a lead may provide the electrical contact to the heart tissue for delivery of the electrical pulses generated by the pulse generator and delivered to the electrode through the lead.
The use of wired leads may limit the number of sites of heart tissue at which electrical energy may be delivered. For example, most commercially available pacing leads are not indicated for use in the left side of the heart. One reason is that the high pumping pressure on the left side of the heart may cause a thrombus or clot that forms on a bulky wired lead to eject into distal arteries, thereby causing stroke or other embolic injury. Thus, in order to pace the left side of the heart with a wired lead, most wired leads are directed through the cardiac venous system to a site (external to the left heart chambers) in a cardiac vein over the left side of the heart. While a single lead may occlude a cardiac vein over the left heart locally, this is overcome by the fact that other cardiac veins may compensate for the occlusion and deliver more blood to the heart. Nevertheless, multiple wired leads positioned in cardiac veins can cause significant occlusion, thereby limiting the number of heart tissue sites at which electrical energy may be delivered to the left side of the heart.
Some pacing systems may use wireless electrodes that are attached to the epicardial surface of the heart (external to the heart chambers) to stimulate heart tissue. In these systems, the wireless electrodes are screwed into the outside surface of the heart wall, which can reduce the effectiveness of the electrical stimulation in some circumstances.
SUMMARYSome embodiments of pacing systems employ wireless electrode assemblies to provide pacing therapy. The wireless electrode assemblies may receive energy via an inductive coupling so as to provide electrical stimulation to the surrounding heart tissue. In certain embodiments, a wireless electrode assembly may be directed through a guide catheter in a heart chamber to deliver at least a portion of the wireless electrode assembly through the endocardium. For example, the electrode assembly may include first and second fixation devices to secure the electrode assembly to the heart chamber wall. In such circumstances, the first fixation device may oppose rearward migration of the electrode assembly out of the heart chamber wall, and the second fixation device may oppose forward migration into the heart chamber wall. Accordingly, the wireless electrode assembly can be readily secured to the heart chamber wall and incorporated into the surrounding heart tissue over a period of time.
In some embodiments, a wireless electrode assembly may include a body portion that at least partially contains a circuit to electrically stimulate an electrode. The wireless electrode assembly may also include first and second biased tines to shift from a loaded condition to an outwardly extended condition to secure the body portion to a heart chamber wall. The first and second biased tines may be generally opposed to one another.
Particular embodiments may include an electrode delivery system for delivering a wireless electrode assembly into a heart chamber. The system may include a wireless electrode assembly including a body portion and first and second biased tines to shift from a loaded condition to an outwardly extended condition to secure the body portion to a heart chamber wall. The first and second biased tines may oppose one another. The system may also include a delivery catheter to direct the wireless electrode assembly through a heart chamber and toward a heart chamber wall. The delivery catheter may include an opening in a distal end such that, when the wireless electrode assembly is separated from the opening in the distal end of the catheter, the first and second biased tines shift from the loaded condition to the outwardly extended condition.
Some embodiments may include a method of inserting a wireless electrode assembly into a heart chamber wall. The method may include inserting a first biased tine of a wireless electrode assembly through a portion of endocardium and into a heart chamber wall. The first biased tine may shift from a loaded condition to an outwardly extended condition to secure the body portion to a heart chamber wall. The method may also include causing a second biased tine of the wireless electrode assembly to shift from the loaded condition to the outwardly extended condition to secure the body portion to a heart chamber wall. The first and second biased tines may be generally opposed to one another when in their respective outwardly extended conditions.
These and other embodiments described herein may provide one or more of the following advantages. First, the wireless electrode assemblies may eliminate or otherwise limit the need for wired pacing leads, thereby reducing the risk of stroke or other embolic injury from a thrombus or clot and reducing the risk of occluding cardiac veins (external to the heart chambers). Second, the wireless electrode assemblies may be secured to the inner wall of one more heart chambers, which may provide more efficient transfer of electrical stimulation. Third, the wireless electrode assemblies may be secured to a heart chamber wall in a manner that opposes both forward migration and rearward migration of the electrode assembly. In such circumstances, the secure attachment of the wireless electrode assembly with the heart wall may increase the likelihood of incorporating the electrode assembly into surrounding tissue, thereby further reducing the likelihood of forming a thrombus or clot in the heart chamber.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
FIGS. 7A-D are partial cross-sectional views of the delivery of the wireless electrode assembly of
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS Referring to
The distal end of each wireless electrode assembly 120 may include one or more fixation devices, such as tines As described in more detail below in connection with
Referring still to
The transmitter 50—which is in communication with, and is controlled by, the pacing controller 40—may drive an RF signal onto the antenna 60. In one embodiment, the transmitter 50 provides both (1) a charging signal to charge the electrical charge storage devices contained within the wireless electrode assemblies 120 by inductive coupling, and (2) an information signal, such as a pacing trigger signal, that is communicated to a selected one or more of the wireless electrode assemblies 120, commanding that wireless electrode assembly 120 deliver its stored charge to the adjacent heart tissue.
One parameter of the wireless electrode assembly 120 that may affect the system design is the maximum energy required to pace the ventricle 34, 38 or other chamber of the heart 30. This energy requirement can include a typical value needed to pace ventricular myocardium, but also can include a margin to account for degradation of contact between the electrodes and tissue over time. In certain embodiments, each wireless electrode assembly 120 may require the maximum pacing threshold energy. This threshold energy is supplied to the wireless electrode assemblies between heartbeats by an external radio frequency generator (which may also be implanted), or other suitable energy source that may be implanted within the body. Parameter values for some embodiments may be:
-
- Threshold pacing voltage=2.5 Volts
- Typical lead impedance=600 Ohms
- Typical pulse duration=0.4 mSec
- Derived threshold energy=4 micro-Joules
Because RF fields at frequencies higher than about 200 kHz may be attenuated by the body's electrical conductivity, and because electric fields of any frequency may be attenuated within the body, energy transmission through the body may be accomplished in some embodiments via a magnetic field at about 20-200 kHz (or by a magnetic field pulse that contains major frequency components in this range), and preferably by transmission of magnetic fields in the range of 100-200 kHz when transmission is through relatively conductive blood and heart muscle.
Still referring to
The external programmer 70 is used to communicate with the pacing controller 40, including after the pacing controller 40 has been implanted. The external programmer 70 may be used to program such parameters as the timing of stimulation pulses in relation to certain sensed electrical activity of the heart, the energy level of stimulation pulses, the duration of stimulation pulse (that is, pulse width), etc. The programmer 70 includes an antenna 75 to communicate with the pacing controller 40, using, for example, RF signals. The implantable pacing controller 40 is accordingly equipped to communicate with the external programmer 70, using, for example, RF signals. The antenna 60 may be used to provide such communications, or alternatively, the pacing controller 40 may have an additional antenna (not shown in
Still referring to
In some embodiments, the antenna 60 may be a loop antenna comprised of a long wire that is electrically connected across an electronic circuit contained within the controller/transmitter housing, which circuit delivers pulses of RF current to the antenna 60, generating a magnetic field in the space around the antenna 60 to charge the wireless electrode assemblies 120, as well as RF control magnetic field signals to command the wireless electrode assemblies 120 to discharge. In such embodiments, the antenna 60 may comprise a flexible conductive material so that it may be manipulated by a physician during implantation into a configuration that achieves improved inductive coupling between the antenna 60 and the coils within the implanted wireless electrode assemblies 120. In one example, the loop antenna 60 may be about 2 to 22 cm long, and about 1 to 11 cm wide, and may be about 5 to 11 cm long, and about 3 to 7 cm wide. Placement of the antenna 60 over the ribs may provide a relatively large antenna to be constructed that has improved efficiency in coupling RF energy to the pacing wireless electrode assemblies 120.
As shown in
As previously described, in some embodiments, each of the wireless electrode assemblies 120 includes a rechargeable battery or other charge storage device. This battery may provide power for delivering pacing energy to the tissue, and for operating communications, logic, and memory circuitry contained within the assembly. In some alternative embodiments, a transmitter and an antenna may be external to the patient (as opposed to the implantable transmitter 50 and antenna 60 depicted in
Referring to
Referring to
The switch device 124, in this example, is a voltage-controlled device and is connected to sense a voltage across the capacitor 125 to determine when the capacitor 125 has been sufficiently charged to a specified pacing threshold voltage level. When the capacitor 125 is sensed to have reached the specified pacing threshold level, the voltage-controlled switch device 124 moves to a position 2, which disconnects the capacitor 125 from the coil 122. With the switch device 124 in the position 2, the capacitor 125 is electrically isolated and remains charged, and thus is ready to be discharged. The voltage controlled switch device 124 may comprise a solid state switch, such as a field effect transistor, with its gate connected to the output of a voltage comparator that compares the voltage on capacitor 125 to a reference voltage. The reference voltage may be set at the factory, or adjusted remotely (e.g., after being implanted) via signals sent from the physician programmer unit 70 (
Still referring to
With the switch device 124 in the position 3, the capacitor 125 may be connected in series through two bipolar electrodes 121 and 129, to the tissue to be stimulated. As such, at least some of the charge that is stored on the capacitor 125 is discharged through the tissue. When this happens, the tissue becomes electrically depolarized. In one example embodiment described in more detail below, the bipolar electrodes 121 and 129 across which stimulation pulses are provided are physically located at opposite ends (e.g., a proximal end and a distal end) of the wireless electrode assembly 120. After a predetermined, or programmed, period of time, the switch returns to position 1 so the capacitor 125 may be charged back up to the selected threshold level.
It should be noted that, for sake of clarity, the schematic diagram of
Using wireless electrode assemblies of the type shown in
Pending U.S. patent application Ser. No. 10/971,550 (filed on Oct. 20, 2004), Ser. No. 11/075,375 (filed on Mar. 7, 2005), and Ser. No. 11/075,376 (filed on Mar. 7, 2005), all owned by the assignee of this application, describe various features of wireless electrode assemblies, systems to deliver the wireless electrode assemblies to the heart, and electronic components to activate the wireless electrode assemblies to deliver electrical stimulation. It should be understood from the description herein that some of the features described in these three patent applications (Ser. Nos. 10/971,550, 11/075,375, and 11/075,376) may be applicable to particular embodiments described herein.
Referring now to
After the guide catheter 110 is deployed into the targeted heart chamber, the wireless electrode assemblies 120 may be advanced into the heart tissue through the guide catheter 110 using at least one delivery catheter 115. The wireless electrode assemblies 120 may be consecutively delivered through the guide catheter 110 using at least one delivery catheter 115. In some embodiments, the delivery catheter 115 may include at least one marker band 116 to permit viewability of the distal end of the delivery catheter 115 using medical imaging techniques. The delivery catheter 115 may include a steering mechanism (e.g., steering wires, shape memory device, or the like) to shift the distal end. For example, the delivery catheter 115 may comprise a shape memory device (e.g., one or more wires comprising Nitinol or another shape memory material) to provide a predetermined curvature near the distal end of the delivery catheter 115. The shape memory device may be activated by a change in electrical charge or by a change in temperature. In one example, the delivery catheter 115 may include a shape memory device near the distal end that is capable of providing a 90-degree deflection curve near the distal end immediately before a longitudinally straight section at the distal end of the catheter 115.
In some approaches to the targeted tissue, the steering mechanism (e.g., steering wires, shape memory device, or the like) of the delivery catheter 115 can be manipulated so that a deflected portion near the distal end of the delivery catheter abuts against the septum wall of the targeted heart chamber. For example, the deflected portion of the delivery catheter may abut against the septum wall 39 between the left ventricle 34 and the right ventricle 38 while a longitudinally straight section of the catheter 115 extends the distal end against the targeted heart chamber wall to receive the wireless electrode assembly 120 (refer to the dotted-line example depicted in
The delivery catheter 115 includes an opening at the distal end in which an associated wireless electrode assembly 120 is retained in a loaded position. The wireless electrode assembly 120 may include a body portion that has a length and a radius configured to be retained with the delivery catheter 115. As described in more detail below, some embodiments of the body portion of the wireless electrode assembly 120 may have a radius, for example, of about 1.25 mm or less and may have a length, for example, of about 10 mm or less. Wireless electrode assemblies configured for insertion into an atrial wall may be smaller than those configured for insertion into the ventricle walls.
In the exemplary embodiment shown in
As the wireless electrode assembly 120 is deployed from delivery catheter 115, tines 132 and 134 located externally on the wireless electrode assembly 120 may adjust to a deployed position (e.g., an outwardly extended condition). Such an adjustment to the deployed position may be caused, for example, due to spring bias of the tines 132 and 134 (described in more detail below). When the tines 132 and 134 are in the deployed position, the tines 132 and 134 are capable of securing the wireless electrode assembly 120 to the targeted tissue site (e.g., described in more detail below, for example, in connection with
Referring to
As previously described, the fixation device 132 may include a set of biased tines arranged near the distal end of the wireless electrode assembly 120 so as to secure the wireless electrode assembly 120 to the heart chamber wall. The fixation device 134 may include a first set of biased tines arranged near the proximal end of the wireless electrode assembly 120 which can also serve to secure the assembly 120 to the heart chamber wall. In some embodiments, the tines 134 arranged near the proximal end may have a different configuration and orientation from the opposing tines 132 arranged near the distal end. For example, as shown in the embodiments depicted in
As previously described, the wireless electrode assembly 120 may be arranged in the delivery catheter 115 (
In the embodiment depicted in
In this embodiment depicted in
Still referring to
In the embodiment depicted in
As previously described, the tines 132b and 134b are oriented in an opposing fashion to secure the wireless electrode assembly 120 to the heart tissue in a manner that opposes reward migration and forward migration, thereby permitting incorporation into the surrounding tissue. For example, the proximal tines 134b may flex outwardly when forced against the heart wall tissue, and such an outward flexing action can cause a slight spring back motion to the wireless electrode assembly 120. The distal tines 132b may flex outwardly in response to this slight spring-back motion in the proximal direction, thereby enhancing the engagement of the heart tissue between the distal tines 132b and the proximal tines 134b.
In some embodiments, the proximal tines 134b of the electrode assembly may be nonaligned with the distal tines 132b along the body of the electrode assembly 128. For example, as shown in
It should be understood that in some embodiments of the wireless electrode assembly 120, the distal tines 132 may also serve as at least a portion of the distal electrode 129. Also, in some embodiments, proximal tines 134 may also serve as at least a portion of the proximal electrode 121. For example, the tines 132 and 134 may comprise an electrically conductive material (e.g., stainless steel or another metallic material) and may be electrically connected to the distal and proximal electrode circuitry (respectively).
Referring now to FIGS. 7A-D, some embodiments of the wireless electrode assemblies 120 may be press fit into the conduit of the delivery catheter 115 so that a plunger mechanism 144 may be used to separate the wireless electrode assembly 120 from the delivery catheter 115. As shown in
The wireless electrode assembly 120 may be releasably engaged with the tube portion 142. For example, the wireless electrode assembly 120 may be press-fit into the tube portion 142. In another example, the tube portion 142 may have a square cross-sectional shape, a hexagonal cross-sectional shape, a keyed cross-sectional shape, or other noncircular cross-sectional shape to engage the complementary shaped body of the wireless electrode assembly 120. The tube portion 140 may be substantially rigid so as to retain the fixation devices 132 and 134 of the wireless electrode assembly 120 in a loaded condition (as shown, for example, in
As shown in
Referring to
Referring to
As previously described, in some circumstances, the proximal tines 134a may flex outwardly when forced against the heart wall tissue, and such an outward flexing action can cause a slight spring back motion to the wireless electrode assembly 120. The distal tines 132a may flex outwardly in response to this slight spring-back motion in the proximal direction, thereby enhancing the engagement of the heart tissue 35 between the distal tines 132a and the proximal tines 134a. Such an opposed orientation of the tines 132a and 134a hinders rearward migration and forward migration of the electrode assembly 120. As previously described, the tissue 35 may grow and eventually incorporate the wireless electrode assembly 120 therein, thereby preventing the wireless electrode assembly 120 from dislodgement from the tissue 35. In the example depicted in
Referring to
Still referring to
For example, in some embodiments, electrode assembly 120 can be arranged in the tube portion 142 so that the proximal tines 134b are aligned with deployment slots 146 (
In some embodiments of the delivery catheter 115 described herein, the delivery catheter 115 may be wholly separate from the actuation rod 140 so that the actuation rod 140 slides through a conduit passing through the delivery catheter 115. In such circumstances, the actuation rod 140 may be completely retracted from the delivery catheter so that a second wireless electrode assembly may be detachably coupled to the actuation rod 140 (or to an unused, different actuation rod 140) and then directed through the delivery catheter 115 already disposed in the patient's body. In other embodiments, the delivery catheter 115 and the actuation rod 140 may be coupled to one another. In such circumstances, the delivery catheter 115 and actuation rod 140 may be removed from the guide catheter 110 (
In some embodiments, the delivery catheter 115 may include a tube portion that is configured to retain a plurality of wireless electrode assemblies 120 (e.g., similar to tube portion 142 but having a greater length to receive a multitude of assemblies 120). For example, the delivery catheter may be configured to carry two, three, four, five, ten, twelve, or more electrode assemblies 120 in a serial (end to end) arrangement. As such, the plunger mechanism 144 can be used to force each electrode assembly 120 into different tissue sites without retracting the delivery catheter out of the heart. As described previously, the actuation mechanism may force the plunger 144 in a generally distal direction. In the serially arranged embodiment, the plunger 144 applies the force to the most rearward assembly 120 in the serial arrangement, which in turn applies a force from the distal tip 130 of the most rearward assembly 120 to the proximal end of the next assembly 120 in the serial arrangement. In this fashion, the application of force can propagate through the serial arrangement until the assembly 120 nearest the heart tissue 35 is delivered to the target site (as described previously, for example, in connection with
Some of the embodiments described herein permit a plurality of pacing electrodes to be deployed at multiple pacing sites. The pacing sites may be located in the left atrium 32, the left ventricle 34, the right atrium 36, the right ventricle, or a combination thereof. Furthermore, the pacing electrodes may comprise wired pacing leads 95 (
A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.
Claims
1. A wireless electrode assembly for electrical stimulation of heart tissue, comprising:
- a body portion at least partially containing a circuit to deliver electrical energy to an electrode to electrically stimulate heart wall tissue;
- a first fixation structure extending from the body portion in a generally forward orientation and being biased to shift from a retained condition to an outwardly extended condition to engage heart wall tissue; and
- a second fixation structure extending from the body portion in a generally rearward orientation and being to shift from a retained condition to an outwardly extended condition to engage heart wall tissue.
2. The wireless electrode assembly of claim 1, wherein the first fixation structure comprises at least one tine that opposes forward migration of the body portion through the heart wall tissue when in the outwardly extended condition.
3. The wireless electrode assembly of claim 2, wherein the second fixation structure comprises at least one tine that opposes rearward migration of the body portion through the heart wall tissue when in the outwardly extended condition.
4. The wireless electrode assembly of claim 1, wherein at least the electrode of the body portion is insertable through endocardium and into myocardium of the heart wall tissue.
5. The wireless electrode assembly of claim 4, wherein the body portion has a radius of about 1.25 mm or less, and wherein the body portion has a length of about 10 mm or less.
6. The wireless electrode assembly of claim 1, wherein the first and second fixation structures comprise a material selected from the group consisting of Nitinol, stainless steel, and a nickel-cobalt alloy.
7. The wireless electrode assembly of claim 1, wherein the circuit comprises an internal coil to inductively couple with an external power source coil and comprises an electrical charge storage device that is recharged from current inductively generated by the internal coil.
8. A wireless electrode assembly at least partially implantable through an interior surface of a heart chamber wall, the electrode assembly comprising:
- a body portion having an electrode for electrically stimulating cardiac tissue;
- a first set of tines biased outwardly and extending forwardly from a rearward radial periphery of the body portion, the first set of tines opposing a rearward portion, but not a forward portion, of the body portion from being advanced into the heart chamber wall when the electrode assembly is longitudinally advanced in a forward direction toward the interior surface of the heart chamber wall; and
- a second set of tines extending rearwardly and biased outwardly from a forward radial periphery of the body portion, the second set of tines opposing the forward portion of the body portion from becoming dislodged from heart wall tissue after the longitudinal advancement of the forward body portion into the heart chamber wall.
9. The wireless electrode assembly of claim 8, wherein at least the forward portion of the body portion is insertable through endocardium and into myocardium of the heart wall tissue.
10. The wireless electrode assembly of claim 9, wherein the body portion has a radius of about 1.25 mm or less, and wherein the body portion has a length of about 10 mm or less.
11. The wireless electrode assembly of claim 8, wherein the first set of tines and the second set of tines comprise a material selected from the group consisting of Nitinol, stainless steel, and a nickel-cobalt alloy.
12. The wireless electrode assembly of claim 8, wherein the body portion comprises a circuit that includes an internal coil to inductively couple with an external power source coil and an electrical charge storage device that is recharged from current inductively generated by the internal coil.
13. An electrode delivery system, the system comprising:
- a wireless electrode assembly including a body portion and first and second tines that are biased to shift from a loaded condition to an outwardly extended condition to secure the body portion to a heart chamber wall, the first and second biased tines generally opposing one another; and
- a delivery catheter to direct the wireless electrode assembly through a heart chamber and toward an interior surface of a heart chamber wall, the delivery catheter including an opening in a distal end such that, when the wireless electrode assembly is separated from the opening in the distal end of the catheter, the first and second tines shift from the loaded condition to the outwardly extended condition.
14. The electrode delivery system of claim 13, wherein when the first and second tines shift to the outwardly extended condition, the first tines are outwardly extended in a generally distal orientation and the second biased tines are outwardly extended in a generally proximal orientation.
15. The electrode delivery system of claim 13, further comprising a guide catheter to direct the distal end of the delivery catheter into the heart chamber.
16. The electrode delivery system of claim 15, further comprising an actuation member that includes a push rod device to separate the wireless electrode assembly from the opening in the distal end of the delivery catheter.
17. The electrode delivery system of claim 13, wherein the wireless electrode assembly is releasably retained in the delivery catheter by a tubular wall, the tubular wall comprising one or more deployment slots generally aligned with at least one of the first and second tines.
18. A method of inserting a wireless electrode assembly into a heart chamber wall, comprising:
- inserting a set of distal tines of a wireless electrode assembly through a portion of endocardium and into a heart chamber wall, the set of distal tines being biased to shift from a retained condition to an outwardly extended condition to secure the wireless electrode assembly to a heart chamber wall; and
- causing a set of proximal tines of the wireless electrode assembly to shift from a retained condition to an outwardly extended condition to secure the wireless electrode assembly to the heart chamber wall,
- the set of distal tines extending in a generally rearward orientation when in the outwardly extended condition and the set of proximal tines extending in a generally forward orientation when in the outwardly extended condition.
19. The method of claim 18, wherein a portion of the wireless electrode assembly is secured to the heart chamber so as to be at least partially incorporated into the endocardium of the heart chamber wall over a period of time.
20. The method of claim 18, further comprising delivering the wireless electrode assembly in a delivery catheter to a targeted heart chamber.
21. The method of claim 20, when the set of distal tines and the set of proximal tines are shifted to their respective outwardly extended conditions when the wireless electrode assembly is separated from a distal opening of the delivery catheter.
22. The method of claim 18, further comprising implanting a wireless power source coil proximal to the heart so that the wireless power source coil is arrange for inductive coupling with an internal coil of the wireless electrode assembly.
Type: Application
Filed: Oct 13, 2006
Publication Date: Jun 14, 2007
Applicant: Boston Scientific Scimed, Inc. (Maple Grove, MN)
Inventors: William Drasler (Minnetonka, MN), Michael Pikus (Golden Valley, MN), Roger Hastings (Maple Grove, MN), Scott Smith (Chaska, MN), Martin Willard (Burnsville, MN), Daniel Lafontaine (Plymouth, MN), Douglas Saholt (Mound, MN), Graig Kveen (Maple Grove, MN)
Application Number: 11/549,352
International Classification: A61N 1/05 (20060101);