Abstract: A cardioversion and defibrillation lead system and a method of use of the lead system for applying energy to the heart. The lead system and method of application are designed to maximize the efficiency of electrical energy and depolarizing the cells of the heart by equalizing current distribution across the heart and concentrating current in the muscular areas of the heart. The method of use of the lead system includes properly locating the electrodes, and applying pulses to the electrodes in one of several pulse regimes.

Abstract: A cardioversion and defibrillation lead system and a method of use of the lead system for applying energy to the heart. The lead system and method of application are designed to maximize the efficiency of electrical energy and depolarizing the cells of the heart by equalizing current distribution across the heart and concentrating current in the muscular areas of the heart. The method of use of the lead system includes properly locating the electrodes, and applying pulses to the electrodes in one of several pulse regimes.

Abstract: A single pass atrial-ventricular endocardial lead for transvenous insertion. A ventricular electrode is mounted at the distal end of a ventricular lead sheath and an atrial electrode is mounted at the distal end of an atrial lead sheath which is slideably mounted around the ventricular lead sheath. A connector assembly is mounted at the proximal end of the atrial lead sheath. An adjustment device is provided to allow axial adjustment of the ventricular lead sheath relative to the atrial lead sheath without modification to or adjustment of the connector assembly prior to attachment to an implantable pulse generator.

Abstract: A screw-in endocardial transvenous pacing lead having a lead tip with a sealing membrane. The lead is chronically affixed by a helical fixation coil having a pointed tip which is rotatably advanced through a helical lumen in the lead tip into the endocardial tissue. During transvenous insertion, the helical fixation coil is retracted into a chamber to protect against damage of the vein. A sealing membrane is positioned perpendicularly within the helical lumen of the lead tip preventing ingress of body fluids. The sealing membrane is of silicon rubber with a polyurethane coating on either side. Upon being properly located within the heart, the helical fixation coil is rotatably extended. The pointed tip of the helical fixation coil punctures the sealing membrane normal to its direction of travel. The sealing membrane provides a seal around the helical fixation coil.