Abstract: An implantable cardiac tissue excitation system includes an implantable pacing controller unit with a pulse generation circuit. The system also includes a lead with a lead body extending between a proximal lead end attachable to the pacing controller unit and a distal lead end configured to be implanted within a heart. A lead conductor extends within the lead body. The system also includes a transmitter assembly located near the distal lead end that is electrically connected to the pulse generation circuit through the lead conductor to wirelessly transmit pacing control information and pacing energy. The system also includes a leadless electrode assembly configured to be implanted within the heart that includes a receiver to receive the wireless transmission, a charge storage unit to store the charge energy, and an electrical stimulation circuit to deliver an electrical stimulus to cardiac tissue using the pacing control information and the charge energy.

Abstract: A method of navigating a medical device in an operating region in a subject. The method includes applying a magnetic field to the operating region and changing the magnetic moment of the medical device by selectively changing a physical condition of at least one magnet element in the medical device to change the orientation of the device with respect to the applied magnetic field.

Abstract: The present invention is directed to medical devices that contain at least one tissue contacting surface that is configured to undergo a variation in surface charge in response to a time-dependent signal. Such a variation in surface charge is provided, for example, to enhance or inhibit cellular growth adjacent to, on, or within the at least one tissue contacting surface.

Abstract: A method of navigating a medical device in an operating region in a subject. The method includes applying a magnetic field to the operating region and changing the magnetic moment of the medical device by selectively changing a physical condition of at least one magnet element in the medical device to change the orientation of the device with respect to the applied magnetic field.

Abstract: Various configurations of systems that employ leadless electrodes to provide pacing therapy are provided. In one example, a system that provides multiple sites for pacing of myocardium of a heart includes wireless pacing electrode assemblies that are implantable at sites proximate the myocardium using a percutaneous, transluminal, catheter delivery system. Also disclosed are various configurations of such systems, wireless electrode assemblies, and delivery catheters for delivering and implanting the electrode assemblies.

Abstract: An electrode with an electrode surface having a polyoxometalate (POM). The use of POM with an electrode surface increases the active electrochemical surface area, with a resulting increase in capacitance and impedance, and a decrease of polarization losses at the electrode/tissue interface. In addition, electrodes having POM can include pseudo-capacitive properties from their redox properties and charge storage properties.

Abstract: A method of navigating a medical device having a changeable magnetic moment within an operating region within a patient, the method includes applying a navigating magnetic field to the operating region with an external source magnet, and changing the direction of the magnetic moment in the medical device to change the orientation of the medical device in a selected direction within the operating region. The magnet moment of the medical device can be created by one or more electromagnet coils, in which case the magnetic moment can be changed by changing the current to the coil. Alternatively, the magnetic moment of the medical device can be created by one or more permanent magnets, in which case the magnetic moment can be changed by mechanically or magnetically manipulating the permanent magnet.

Abstract: A method of turning a medical device, having a magnetically responsive element associated with its distal end, at an operating point within an operating region inside a patient's body from an initial direction to a desired final direction, through the movement of at least one external source magnet. The at least one external source magnet is moved in such a way as to change the direction of the distal end of the magnetic medical device from the initial direction to the desired final direction without substantial deviation from the plane containing the initial direction and the desired final direction.

Abstract: A method of navigating the distal end of a medical device through an operating region in a subject's body includes displaying an x-ray image of the operating region, including the distal end of the medical device; determining the location of the distal end of the medical device in a reference frame translatable to the displayed x-ray image; and displaying an enhanced indication of the distal end of the medical device on the x-ray image to facilitate the navigation of the distal end of the device in the operating region.

Abstract: A method of turning a medical device, having a magnetically responsive element associated with its distal end, at an operating point within an operating region inside a patient's body from an initial direction to a desired final direction, through the movement of at least one external source magnet. The at least one external source magnet is moved in such a way as to change the direction of the distal end of the magnetic medical device from the initial direction to the desired final direction without substantial deviation from the plane containing the initial direction and the desired final direction.

Abstract: A method of localizing a medical device inside a patient's body, the method comprising: transmitting ac magnetic signals between a plurality of points of known location outside of the patient's body and a plurality of points on the medical device inside the patient's body, the signals transmitted between at least some of the points comprising at least two different frequencies; and receiving the transmitted ac magnetic signals and processing the received signals to determine the position of the points on the medical device, and thus the location of the medical device, this processing including correcting for the affects of metal in the vicinity by using the transmitted and received signals at different frequencies. In an alternate embodiment, a reference device is provided inside the patients' body, and the medical device is localized relative to the reference catheter.

Abstract: A method of navigating a medical device having a changeable magnetic moment within an operating region within a patient, the method includes applying a navigating magnetic field to the operating region with an external source magnet, and changing the direction of the magnetic moment in the medical device to change the orientation of the medical device in a selected direction within the operating region. The magnet moment of the medical device can be created by one or more electromagnet coils, in which case the magnetic moment can be changed by changing the current to the coil. Alternatively, the magnetic moment of the medical device can be created by one or more permanent magnets, in which case the magnetic moment can be changed by mechanically or magnetically manipulating the permanent magnet.

Abstract: A method for forming an ablation pattern to electrically isolate a vessel having an ostium from a chamber formed within a patient for treatment of cardiac arrhythmia. The distal portion of a catheter is navigated to a chamber. An anchor member is deployed from the distal end of the catheter into the chamber, and the distal end is navigated into the ostium of the vessel, and temporarily secured in the vessel. An ablation member is deployed from the distal end of the catheter into the chamber and successively navigated into contact with tissue adjacent the ostium and ablating the tissue in contact with the ablation member to form a line of ablation. At least one of the navigating the distal portion of the catheter, navigating the anchor member and navigating the ablation member is performed by applying an external magnetic field to orient the device being navigated.

Abstract: A percutaneous system for bypassing a restriction in a native vessel of a mammal having an aorta includes providing a graft having a body portion with a first end, a second end and a lumen therebetween. An aperture is formed in the aorta. The graft is inserted into the aorta and the first end of the graft is connected to the aorta about the aperture in the aorta. An aperture is then formed in the native vessel distal of the restriction. The second end of the graft is connected to the native vessel about the aperture therein such that the lumen in the graft communicates with the aorta and the native vessel.

Abstract: Devices and methods for creating a series of percutaneous myocardial revascularization (PMR) channels in the heart. One method includes forming a pattern of channels in the myocardium leading from healthy tissue to hibernating tissue. Suitable channel patterns include lines and arrays. One method includes anchoring a radiopaque marker to a position in the ventricle wall, then using fluoroscopy repeatedly to guide positioning of a cutting tip in the formation of multiple channels. Another method uses radiopaque material injected into each channel formed, as a marker. Yet another method utilizes an anchorable, rotatable cutting probe for channel formation about an anchor member, where the cutting probe can vary in radial distance from the anchor. Still another method utilizes a multiple wire radio frequency burning probe, for formation of multiple channels simultaneously. Still another method utilizes liquid nitrogen to cause localized tissue death.

Abstract: An electrophysiology catheter includes a tube having a proximal end, a distal end, and a lumen therebetween. The tube is preferably comprised of multiple sections of different flexibility, arranged so that the flexibility of the catheter increases from the proximal end to the distal end. There is a first generally hollow electrode member at the distal end. A magnetically responsive element is disposed at least partially in the hollow electrode, for aligning the distal end of the catheter with an externally applied magnetic field. The end electrode can have openings for delivering irrigating fluid, and/or a sleeve can be provided around the tube to create an annular space for the delivering of irrigating fluid. A temperature sensor can be provided to control the operation of the catheter. A localization coil can also be to sense the position and orientation of the catheter.

Abstract: A method of turning a medical device with the assistance of an externally applied magnetic field, in a direction with a component in a plane perpendicular to the direction of the externally applied magnetic field. The method includes applying first torque to the distal end of the medical device by creating magnetic moment at the distal end of the medical device, and applying a second torque to the distal end of the medical device. The second torque may be created by creating a second magnetic moment at the distal end of the device spaced from the first, by using an electrostrictive device, by using a stylette inserted into the device, by using a fluid-driven shaped tube, or otherwise.

Abstract: A method of magnetically manipulating a medical device within a body part of a human patient in conjunction with MR imaging includes applying a navigating magnetic field with magnets from the MR imaging device, and changing the magnetic moment of the medical device to change the orientation of the medical device within the body part.

Abstract: A method of placing a pacing lead in the heart includes introducing a distal end of a delivery catheter into the patient's vasculature; magnetically navigating the distal end of the delivery catheter to the patient's heart; deploying a pacing lead from the distal end of the delivery catheter; and magnetically navigating the pacing lead to the pacing application site.

Abstract: A method of turning a medical device, having a magnetically responsive element associated with its distal end, at an operating point within an operating region inside a patient's body from an initial direction to a desired final direction, through the movement of at least one external source magnet. The at least one external source magnet is moved in such a way as to change the direction of the distal end of the magnetic medical device from the initial direction to the desired final direction without substantial deviation from the plane containing the initial direction and the desired final direction.