1048 results about "Tunica intima" patented technology

A mapping catheter is positioned in a heart chamber, and active electrode sites are activated to impose an electric field within the chamber. The blood volume and wall motion modulates the electric field, which is detected by passive electrode sites on the preferred catheter. Electrophysiology measurements, as well as geometry measurements, are taken from the passive electrodes and used to display a map of intrinsic heart activity.

The invention provides an apparatus having a tubular member for receiving an endocardial lead implanted within a patient's body. Disposed generally at a distal end of the tubular member is at least one blade or cutting surface. An adjustment mechanism moves the blade between retracted and extended positions to engage the cutting surface with the endocardial lead to cut the lead. Once severed, the cut portion of the lead remains within an inner channel of the tubular member and the apparatus and cut portion of the lead are removed from within the patient. Various embodiments include the blade pivotally connected to the distal end of the tubular member and activated by a wire adjustment mechanism. Others include a metallic wire for slicing through the lead. Still others include a pneumatically actuated adjustment mechanism that inflates to move the blade and engage the cutting surface with the lead.

A system and method for selectively treating aberrant cells such as cancer cells through administration of a train of electrical pulses is described. The pulse length and delay between successive pulses is optimized to produce effects on intracellular membrane potentials. Therapies based on the system and method produce two treatment zones: an ablation zone surrounding the electrodes within which aberrant cells are non-selectively killed and a selective treatment zone surrounding the ablation zone within which target cells are selectively killed through effects on intracellular membrane potentials. As a result, infiltrating tumor cells within a tumor margin can be effectively treated while sparing healthy tissue. The system and method are useful for treating various cancers in which solid tumors form and have a chance of recurrence from microscopic disease surrounding the tumor.

A method and a device for improving cardiac function are provided. The device is packaged in a collapsed state in an end of a catheter. Portions of a frame construction of the device spring outwardly when the catheter is withdrawn from the device. Anchoring formations on the frame construction secure the frame construction to a myocardium of the heart. A membrane secured to the frame construction then forms a division between volumes of an endocardial cavity of the heart on opposing sides of the membrane.

An atrial ablation catheter and methods for its use. The endocardial catheter includes an electrode array particularly adapted to locate and ablate foci of arrhythmia which are required for sustained atrial fibrillation is provided. The array is easily deployed and retracted from the catheter, and presents a distally oriented electrode array that can be pressed against the wall of the atrium.

A system and method for cardiac mapping and ablation include a multi-electrode catheter introduced percutaneously into a subject's heart and deployable adjacent to various endocardial sites. The electrodes are connectable to a mapping unit, an ablation power unit a pacing unit, all of which are under computer control. Intracardiac electrogram signals emanated from a tachycardia site of origin are detectable by the electrodes. Their arrival times are processed to generate various visual maps to provide real-time guidance for steering the catheter to the tachycardia site of origin. In another aspect, the system also include a physical imaging system which is capable of providing different imaged physical views of the catheter and the heart. These physical views are incorporated into the various visual maps to provide a more physical representation. Once the electrodes are on top of the tachycardia site of origin, electrical energy is supplied by the ablation power unit to effect ablation.

Devices and methods for accessing and closing vascular sites are disclosed. Self-sealing closure devices and methods are disclosed. A device that can make both steeply sloping and flat access paths into a vascular lumen is disclosed. The device can also form arteriotomies with sections cleaved between a vessel's intima and adventitia. Methods for using the device are also disclosed.