Abstract: A conductor assembly for a medical device lead includes a helically coiled conductor including a plurality of turns having a coil pitch and an outer diameter and consisting of one filar having a filar diameter. The coil pitch and outer diameter are selected based on the filar diameter to minimize heating of the helically coiled conductor in the presence of an MRI field. A polymer sheath is formed about the helically coiled conductor such that the coil pitch of the unifilar helically coiled conductor is maintained. The polymer sheath is configured to increase a torque transmitting capacity of the helically coiled conductor.

Abstract: The present application includes treatment systems having delivery-activated inflatable members, and associated systems and methods for treating the spinal cord and other tissues. A treatment system in accordance with one embodiment includes a lead body having an opening, an inner surface position around the opening, and an inflatable member carried by the lead body, with at least one of the inflatable member and the lead body including a frangible portion accessible from the opening. The inflatable member can have an expandable interior volume bounded at least in part by the frangible portion. The system can further include a delivery device received in the opening of the lead body and positioned to open a passage through the frangible portions between the interior volume of the inflatable member and the opening of the lead body when the delivery device is removed from the opening of the lead body.

Abstract: Tools and methods are particularly suited for certain cardiac conditions involving use of a catheter for pacing of the right and left ventricles from a lead in the right ventricle, e.g., to facilitate mechanically and/or electrically synchronous contractions for resynchronization. Certain aspects involve pacing and/or mapping by delivering pulses to a cardiac site useful for improving heart function as measured, e.g., by QRS width, fractionation, late LV activation timing, mechanical synchronicity of free wall and septal wall, effective throughput/pressure, or a combination thereof. In one embodiment, a catheter arrangement includes a fixation mechanism to attach the catheter arrangement to heart tissue, individually-addressable electrodes for providing pacing signals to the heart tissue, and an elongated structure that supports the fixation mechanism and the electrodes.

Abstract: Elongate intrabody MRI-antenna probes include opposing distal and proximal portions. The distal portion includes at least one multi-turn conductor arranged as a stack of substantially flat loops, each with a substantially rectangular elongate shape. A flat loop can reside on each of a plurality of adjacent vertically stacked substantially planar layers, the flat loops cooperate to define a MRI receive antenna.

Abstract: The invention describes a steerable sheath for percutaneous epicardial access. The invention also describes a novel lead to facilitate left ventricular pacing and efficient defibrillation.

Abstract: An implantable lead for a medical device with a coplanar coupling for connecting a conductor to a contact reduces conductor bending moments to improve lead reliability. The implantable lead comprises a lead body having a proximal end and a distal end, at least one conductor, at least one contact carried on the proximal end, at least one contact carried on the distal end, and at least one coupling. The lead body has an exterior surface. The conductor is contained in the lead body and extends from the lead proximal end to the distal end. The conductor is also electrically insulated. The contact carried on the proximal end is electrically connected to the conductor. The coupling has a conductor coupling and a contact coupling. The conductor coupling is placed over the conductor and attached to the conductor. The contact coupling exits the lead body and has a weld to connect the contact coupling to the contact.

Abstract: A cardiac medical device and associated method control delivery of dual chamber burst pacing pulses in response to detecting tachycardia. In one embodiment, a single chamber pacing pulse is delivered in response to detecting a tachycardia. Dual chamber pacing pulses are delivered subsequent to the single chamber pacing pulse. An intrinsic depolarization is sensed subsequent to delivering the dual chamber pacing pulses. The tachycardia episode is classified in response to the sensed intrinsic depolarization.

Abstract: Systems and methods are provided for reducing heating within pacing/sensing leads of a pacemaker or implantable cardioverter-defibrillator that occurs due to induced radio frequency (RF) currents during a magnetic resonance imaging (MRI) procedure, or in the presence of other sources of strong RF fields. For example, bipolar coaxial leads are described wherein the ring conductor of the lead is disconnected from the ring electrode via a switch in response to detection of MRI fields to convert the ring conductor into an RF shield for shielding the inner tip conductor of the lead so as to reduce the strength of RF currents induced therein and hence reduce tip heating. Other exemplary leads are described wherein a band stop filter is instead used to block RF signals to likewise convert the ring conductor into an RF shield. The switches and band stop filters also help to prevent MRI-induced stimulation.

Abstract: This disclosure describes implantable medical leads that include a lead body and an electrode. A width of the electrode as measured along a longitudinal direction of the lead varies about the perimeter of the lead. The uneven width of the electrode may bias a stimulation field in a particular direction, e.g., a radial or transverse direction relative to the longitudinal axis of the lead. Electrodes with an uneven width may be useful for controlling the direction of propagation of the stimulation field in order to, for example, avoid phrenic nerve stimulation during LV pacing or neck muscle stimulation during vagal neurostimulation.

Abstract: A tissue electrode assembly includes a membrane configured to form an expandable, conformable body that is deployable in a patient. The assembly further includes a flexible circuit positioned on a surface of the membrane and comprising at least one base substrate layer, at least one insulating layer and at least one planar conducting layer. An electrically-conductive electrode covers at least a portion of the flexible circuit and a portion of the surface of the membrane not covered by the flexible circuit, wherein the electrically-conductive electrode is foldable upon itself with the membrane to a delivery conformation having a diameter suitable for minimally-invasive delivery of the assembly to the patient.

Abstract: Some embodiments of a cardiac stimulation system may include a plurality of electrode assemblies that are interconnected by one or more wires while at least one of the electrode assemblies (e.g., a control electrode) wirelessly receives energy through inductive coupling with a power communication unit external to the heart (e.g., a device implanted along one or more ribs). These embodiments may provide an arrangement for efficient inductive coupling from the power communication unit to the control electrode. Also, in some circumstances, the cardiac stimulation system may eliminate the need for wired leads that extend to a location outside the heart, thereby reducing the likelihood of infection that passes along the wire and into the heart.

Abstract: Exemplary techniques and systems for interpolating left ventricular pressures are described. One technique interpolates pressures within the left ventricle from blood pressures gathered without directly sensing blood pressure in the left ventricle.

Abstract: Disclosed herein, among other things, is an implantable medical device header assembly with an optical interface. The header assembly can include a housing defining a cavity; an electrical contact disposed along the cavity; an electrical conductor configured to electrically couple the electrical contact with the implantable medical device; and an optical conductor. The header assembly can include a housing defining a first cavity for receiving a proximal end of an electrical lead; and a second cavity for receiving a proximal end of an optical lead. The header assembly can include a housing configured to be coupled to the implantable medical device, the housing defining a lead port for receiving a proximal end of a lead, the port configured to be in electrical and optical communication with the lead; a transducer disposed within the housing, and an electrical conductor disposed within the housing. Other aspects and embodiments are provided herein.

Abstract: A medical lead includes a pitted, grooved or threaded electrode array tip and a flexible tube or sheath encompassing the electrode array located near the lead tip. In some embodiments, the electrode array adheres to tissue, the tube or sheath adheres to the electrode array at the distal end of the electrode array or the tube or sheath adheres to tissue at the proximal end of the tube or sheath. Embodiments of the tube or sheath may be made from biodegradable material and can include electrode windows spaced along the tube or sheath corresponding to placement of electrode contacts of the electrode array.

Abstract: A lead includes a lead body extending from a distal end to a proximal end, and at least one conductor disposed within the lead body and extending from the distal end to the proximal end of the lead body. The lead further includes an outer terminal ring, a terminal pin, and an insulative sleeve disposed between the outer terminal ring and the terminal pin, where the insulative sleeve is coupled with the outer terminal ring with a snap-fit connection. A pin latch is disposed on an outer periphery surface of the insulative sleeve, where the pin latch is rotatable about a hinge point.

Abstract: An assembly of a pulmonary venting catheter and a pacing wire disposed therethrough whereby the pacing wire is extended from the distal end of the catheter tube during pacing mode, eliminating the need for exchanging the venting catheter with a pacing catheter to begin pacing after venting. The pacing wire includes a flexible distal end for a first conductor to conductively engage heart tissue after the pacing wire is extended from the catheter distal end; a second conductor, also exposed outside the catheter distal end, completes the circuit. The pacing wire is lockable in unextended and extended positions at the proximal end portion of the assembly. A method for venting and pacing a patient's heart during cardiac surgery is described, which includes retracting the catheter distal end from the pulmonary artery after venting mode, into the right ventricle during pacing mode, whereafter the pacing wire is extended for pacing.

Abstract: An implantable monitoring device includes a flexible lead body that includes at least one sensing element. The device also includes a rigid main body connected to the flexible lead body at an attachment point. The rigid main body is generally centered about a longitudinal axis defined by the flexible lead body when the lead body is unflexed. The device further includes a measurement circuit, which is housed within the rigid main body and electrically coupled to the at least one sensing element of the flexible lead body and at least another sensing element on an outside surface of the rigid main body. The measurement circuit is configured to measure a potential difference between the at least one sensing element of the flexible lead body and the at least another sensing element of the main body.

Abstract: Techniques are provided for detecting heart failure or other medical conditions within a patient using an implantable medical device, such as pacemaker or implantable cardioverter/defibrillator, or external system. In one example, physiological signals, such as immittance-based signals, are sensed within the patient along a plurality of different vectors, and the amount of independent informational content among the physiological signals of the different vectors is determined. Heart failure is then detected by the implantable device based on a significant increase in the amount of independent informational content among the physiological signals. In response, therapy may be controlled, diagnostic information stored, and/or warning signals generated. In other examples, at least some of these functions are performed by an external system.

Abstract: An electrical lead for a cardiac device includes a body having a distal end sized for insertion through a catheter, first and second electrodes extending through the body, with each electrode terminating in a tip having proximal and distal ends and arranged to extend to an area of cardiac tissue. The tips include a fully insulated portion on the proximal and distal ends measuring in a range between 5 percent and 40 percent of the lengths of the tips, and further include an uninsulated intermediate section. The tip of the second electrode includes a helical section surrounding the first electrode and has an insulated portion on an inwardly facing portion surface facing toward the first electrode. The tip of the second electrode also includes a fully insulated portion on the proximal and distal ends measuring in the same or similar percentage range.

Abstract: A system for determining the proximity of the esophagus to the ablation electrode of an ablation catheter during an ablation procedure is disclosed. The system comprises an ablation catheter having at least one ablation electrode, an esophageal probe catheter having at least one electrode, and a signal processing unit. Both the ablation electrode and the esophageal probe catheter are electrically connected to the signal processing unit. The signal processing unit receives electrical signals from the ablation electrode on the ablation catheter and the electrode on the esophageal probe catheter and compares the signals to determine the proximity of the esophagus to the ablation electrode.

Abstract: A medical electrical lead includes a lead body, an inner assembly extending throught the lead body, an outer insulative layer covering the inner assembly, and an electrode mounted outside the exterior surface of the outer insulative layer. The inner assembly includes an elongate inner structure forming a lumen, an elongate conductor extending along an outer surface of the inner structure, and a conductive fitting coupled to the elongate conductor.

Abstract: Various embodiments relating to MRI safe, multi-polar active fixation stimulation leads with co-radial construction are disclosed. Some embodiments, allow the use of the generally smaller diameter co-radially constructed body (coated wires) to construct an active fixation lead, with an extendable/retractable fixation mechanism. Some embodiments use a connector assembly with an inner terminal ring, a terminal pin partially rotatably positioned within the annular inner terminal ring, and one or more resilient C-clips disposed within circumferential recesses. The resilient C-clips mechanically and electrically couple the inner terminal ring and the terminal ring while substantially limiting relative longitudinal translation of the terminal pin.

Abstract: The invention relates to an intracardial implantable electrode line for connection to an implantable medical device, in particular a cardiac pacemaker or cardioverter/defibrillator or the like, which has an acceleration sensor in the area of its distal end, which is implemented to record and differentiate acceleration values in at least two different directions. The invention additionally relates to a cardiac stimulation configuration which also has a cardiac stimulator in addition to such an electrode line.

Abstract: A medical device includes a pulse generator, an electrode configured to contact tissue in a coronary vessel, a lead comprising a lead conductor, the lead conductor connecting the pulse generator with the electrode, and a filter circuit electrically connected in series between the lead conductor and the electrode. The filter circuit may include a band pass filter that attenuates signals having a frequency other than a natural resonance frequency (e.g. MRI device signals), and the pulse generator may transmit therapy signals to the electrode as a sinusoidal voltage wave at the natural resonance frequency. The filter circuit may include a diode that rectifies the sinusoidal voltage wave before the rectified sinusoidal voltage wave passes to the electrode. In some embodiments, therapy signals may be provided to the electrode through the band pass filter over a natural resonance frequency range.

Abstract: In a method for manufacturing active fixation helices for the stimulation and/or sensing of organs, an elongated helix precursor body is produced that has one or more electrical conductors surrounded by an insulating material. This helix precursor body is then shaped into a helix, material removed in predetermined places in order to expose the areas of the conductors which will be used as electrodes in the final product. The body is coated with an electrically conducting biocompatible coating which is subsequently partly removed in continuous loops from around the electrodes in order to electrically insulate them from each other and to ensure that the electrically active areas of the electrodes are of the correct dimensions.

Abstract: In one embodiment, a neurostimulation lead comprises an elongated body of insulative material, comprising a first end portion and a second end portion; a plurality of terminals longitudinally positioned along the first end portion; a plurality of electrodes longitudinally positioned along the second end portion; a plurality of conductors electrically coupling the plurality of electrodes to the plurality of terminals; a flexible metal longitudinal stiffener positioned within the elongated body wherein the stiffener has a plurality of longitudinal zones and each zone has a different column strength, the column strength of one or more zones of the plurality of longitudinal zones being defined by cuts or gaps in the stiffener, the stiffener causing the neurostimulation lead to exhibit a greatest amount of column strength adjacent to one end portion of the elongated body and to transition to a lower column strength toward a medial portion of the elongated body.

Abstract: Disclosed herein is an implantable medical lead. In one embodiment, the lead includes a ring electrode, a tip electrode, first and second helically wound coaxial conductor coils, and a distal coil transition. The coils extend between the proximal and distal ends of the lead. The distal coil transition is proximal to the ring electrode and near the distal end and is where the first coil transitions from being outside the second coil proximal of the distal coil transition to being inside the second coil distal of the distal coil transition.

Abstract: Implantable medical leads with magnetic shielding and methods of shielding implantable leads from magnetic fields during medical procedures such as magnetic resonance imaging (MRI) are disclosed. An exemplary implantable medical lead includes a helically coiled inner electrode conductor wire, a helically coiled outer electrode conductor wire disposed radially about the inner electrode conductor wire, and at least one layer of insulation that electrically isolates the inner and outer electrode conductor wires. The inner electrode conductor wire can have a hollowed, multifilar configuration including six or more co-radially wound wire filars. The outer electrode conductor wire is electrically isolated from the inner electrode conductor wire, and may have either a single or double filar configuration.

Abstract: A method and apparatus for retaining a medical device within a blood vessel are described. A medical device (e.g. a pulse generator or a lead) is positioned within a blood vessel. An expandable the retention sleeve is passed into the vessel adjacent to the medical device and expanded to an expanded position to engage the medical device between an exterior surface of the retention sleeve and a surface of the vessel.

Abstract: This document discusses, among other things, a lead body extending longitudinally along a lead axis, a driver axially displaceable relative to the lead body, and a driven member coupled to the lead body and displaceable away from the lead axis. The driven member at least partially defines an expandable passage having at least one internal dimension. The driver is displaceable into the expandable passage and has at least one outer dimension that is larger than the at least one internal dimension of the expandable passage. An example method includes disposing a first member having a first cross-section in a lead assembly having a lead axis, an expandable passage, and a displaceable member proximate the expandable passage. The method further includes urging the first member into the expandable passage in the lead assembly, and urging the displaceable member away from the lead axis to expand the expandable passage.

Abstract: A delivery system for implanting a leadless cardiac pacemaker into a patient is provided. The cardiac pacemaker can include a docking or delivery feature having a through-hole disposed on or near a proximal end of the pacemaker for attachment to the delivery system. In some embodiments, the delivery catheter can include first and second tethers configured to engage the delivery feature of the pacemaker. The tethers, when partially aligned, can have a cross-sectional diameter larger than the through-hole of the delivery feature, and when un-aligned, can have a cross-sectional diameter smaller than the through-hole of the delivery feature. Methods of delivering the leadless cardiac pacemaker with the delivery system are also provided.

Abstract: A lead delivery apparatus includes an electrically conductive lead for an implantable medical device, a delivery shaft for delivering the lead to a target site, a fixator and a pulley structure. A flexible member is coupled to the delivery shaft and the lead and engages the pulley structure such that pulling a first portion of the flexible member moves the lead to the target site.

Abstract: Medical lead systems utilizing electromagnetic bandstop filters are provide which can be utilized in a magnetic resonance imaging (MRI) environment for patients who have implanted medical devices. The medical lead system includes an implanted lead having at least one bandstop filter associated therewith, for attenuating current flow through the lead over a range of frequencies. The bandstop filter has an overall circuit Q wherein the resultant 3 dB bandwidth is at least 10 kHz. The values of capacitance and inductance of the bandstop filter are selected such that the bandstop filter is resonant at a selected center frequency. Preferably, the bandstop filter has an overall circuit Q wherein the resultant 10 dB bandwidth is at least 10 kHz. Such bandstop filters are backwards compatible with known implantable deployment systems and extraction systems.

Abstract: A lead, method of manufacturing same, and system for stimulation is provided. The lead includes an insulative member or layer that masks a portion of the electrode(s) to effectively generate a directional lead that focuses or directs the stimulation to desired location(s). In another embodiment, the lead further includes a marking system to allow a clinician to orient the directional lead, as desired, while the lead is within a body.

Abstract: An implantable medical device, such as a lead or lead extension, includes a body having a distal end portion and a proximal end portion configured to be at least partially received by an apparatus. The device further includes a conductive member at the distal end portion of the body and an electrical contact at the proximal end portion of the body. The electrical contact is electrically coupled to the conductive member and is positioned such that, when received by the apparatus, at least a portion of the apparatus is capable of electrically coupling to the electrical contact. The device further includes a reinforcement member integrated in the body.

Abstract: Exemplary lead assemblies include a lead body having a plurality of conductor wires embedded therein, a plurality of electrode contacts at least partially disposed on an outer surface of the lead body, and a plurality of switching networks each configured to control an operation of one or more of the plurality of electrode contacts.

Abstract: A control system alters one or more characteristics of an ablating element to ablate tissue. In one aspect, the control system delivers energy nearer to the surface of the tissue by changing the frequency or power. In another aspect, the ablating element delivers focused ultrasound which is focused in at least one dimension. The ablating device may also have a number of ablating elements with different characteristics such as focal length. The invention provides an ablation apparatus and methods for ablating tissue wherein the ablation apparatus may have ablating elements that are moveable relative to the tissue to be ablated without the need to relocate the apparatus as a whole.

Abstract: A lead having an extendable and retractable fixation mechanism has a rotating terminal pin at the terminal end which rotates the fixation mechanism at the distal end. As the terminal pin is rotated, the fixation mechanism is extended or retracted from the distal end of the lead. A threaded collar allows for the fixation mechanism to smoothly extend and retract from the lead, and allows for a 1:1 turn ratio between the terminal pin and the fixation mechanism. A fluoroscopic ring disposed at the distal end of the lead provides information during the implantation process.

Abstract: The present invention encompasses apparatus and methods for mapping electrical activity within the heart. The present invention also encompasses methods and apparatus for creating lesions in the heart tissue (ablating) to create a region of necrotic tissue which serves to disable the propagation of errant electrical impulses caused by an arrhythmia.

Abstract: A mapping catheter comprises a catheter body and a mapping assembly. The catheter body has an outer wall, proximal and distal ends, and at least one lumen extending therethrough. The mapping assembly comprises a generally straight proximal region attached to the catheter body, a generally circular main region distal the proximal region having an outer circumference, and a generally straight distal region distal the main region. The mapping assembly also comprises a support member having shape-memory, a non-conductive covering over the support member, and a plurality of electrodes on the non-conductive covering along the generally circular main region.

Abstract: A family of catheter electrode assemblies includes a flexible circuit having a plurality of electrical traces and a substrate; a ring electrode surrounding the flexible circuit and electrically coupled with at least one of the plurality of electrical traces; and an outer covering extending over at least a portion of the electrode. A non-contact electrode mapping catheter includes an outer tubing having a longitudinal axis, a deployment member, and a plurality of splines, at least one of the plurality of splines comprising a flexible circuit including a plurality of electrical traces and a substrate, a ring electrode surrounding the flexible circuit and electrically coupled with at least one of the plurality of electrical traces; and an outer covering extending over at least a portion of the ring electrode. A method of constructing the family of catheter electrode assemblies is also provided.

Abstract: In general, the disclosure is directed toward releasing material within a medical device via an optical feedthrough. A system for releasing material with a medical device comprises a cup that holds a material, wherein the cup includes a discharge port, a seal disc that seals the material within the cup, an optical feedthrough assembly coupled to the cup, a shell that defines a chamber within a medical device, wherein the optical feedthrough assembly is coupled to the shell, and a radiant energy source that shines a beam through the optical feedthrough assembly to puncture the seal disc to allow the material to enter the chamber via the discharge port.

Abstract: Implantable hermetically sealed structures and methods for making the same. Devices, systems and kits including the hermetically sealed structures, as well as methods of using such devices and systems are included.

Abstract: A pacing lead for a left cavity of the heart, implanted in the coronary system. This lead (24) includes a lead body with a hollow sheath (26, 28) of deformable material, having a central lumen open at both ends, and at least one telescopic microcable (42) of conductive material. The microcable slides along the length of the lead body and extends beyond the distal end (32) thereof. The party emerging beyond the distal end is an active free part (34) comprising a plurality of distinct bare areas (36, 38, 50, 50?, 50?), intended to come into contact (40) with the wall of a target vein (22) of the coronary system (14-22), so as to form a network of stimulation electrodes electrically connected together in parallel. The microcable further comprises, proximally, a connector to a generator of active implantable medical device such as a pacemaker or a resynchronizer.

Abstract: An implantable monitoring device includes a flexible lead body that includes at least one sensing element. The device also includes a rigid main body connected to the flexible lead body at an attachment point. The rigid main body is generally centered about a longitudinal axis defined by the flexible lead body when the lead body is unflexed. The device further includes a measurement circuit, which is housed within the rigid main body and electrically coupled to the at least one sensing element of the flexible lead body and at least another sensing element on an outside surface of the rigid main body. The measurement circuit is configured to measure a potential difference between the at least one sensing element of the flexible lead body and the at least another sensing element of the main body.

Abstract: An electrode for use on a medical device is disclosed. The electrode may have a main body of electrically conductive material extending along an axis and having a proximal end and a distal end. The body may be configured to emit electrical energy in accordance with a predefined diagnostic or therapeutic function. The body may have a groove disposed over an outermost surface of the body. The electrode may also include a magnetic resonance imaging (MRI) tracking coil disposed in said groove. The MRI tracking coil may comprise electrically insulated wire, for example. A catheter including an electrode, as well as a method for determining the location of an electrode, are also disclosed.

Abstract: An implantable lead assembly includes an outer jacket, first and second coiled conductors, and first and second electrodes. The outer jacket is elongated along a center axis and includes a body that radially extends between opposite interior and exterior surfaces. The interior surface defines an elongated lumen. The coiled conductors are held within the body of the outer jacket between the interior and exterior surfaces of the outer jacket and are wrapped around the lumen and the center axis. The electrodes are coupled with the outer jacket and electrically coupled to the coiled conductors in order to at least one of deliver stimulus pulses or sense electrical activity.

Abstract: Medical lead systems utilizing electromagnetic bandstop filters are provide which can be utilized in a magnetic resonance imaging (MRI) environment for patients who have implanted medical devices. The medical lead system includes an implanted lead having at least one bandstop filter associated therewith, for attenuating current flow through the lead over a range of frequencies. The bandstop filter has an overall circuit Q wherein the resultant 3 dB bandwidth is at least 10 kHz. The values of capacitance and inductance of the bandstop filter are selected such that the bandstop filter is resonant at a selected center frequency. Preferably, the bandstop filter has an overall circuit Q wherein the resultant 10 dB bandwidth is at least 10 kHz. Such bandstop filters are backwards compatible with known implantable deployment systems and extraction systems.

Abstract: Implantable cardiac monitoring and stimulation methods and devices with epicardial leads having sensor feedback. A fixed or extendable/retractable sensor may be displaceable within the lead's lumen and configured to sense the presence of an anatomical feature or physiological parameter of cardiac tissue in proximity with the lead body's distal end. The sensor may include an ultrasonic sensing element, a perfusion sensor, a photoplethysmographic sensor, or a blood oximetry sensor. Methods of determining suitability for implanting a lead involve the steps of accessing an epicardial surface of the heart, and moving the cardiac lead to an implant site at the epicardial surface. A transmitted signal is directed at the implant site. A reflected signal is received, indicative of the presence of a blood vessel at the implant site. A determination may be made to determine whether the implant site is suitable or unsuitable based on the reflected signal.

Abstract: Apparatus and methods for performing surgery within an organ or vessel are provided. A catheter is provided having a longitudinal axis and an end region carrying an end effector, the end region movable to a series of positions along the longitudinal axis and with an selectable orientation relative to the longitudinal axis. The catheter includes elements for stabilizing the end region of the apparatus within an organ or vessel, and for counteracting reaction forces developed during actuation of the end effector.