Abstract: Myocardial sutureless unipolar lead including an insulated conductor coil adjacent to a base pad, and a barbed electrode spaced adjacent to the base pad and connected to the conductor coil. The sutureless myocardial unipolar lead requires no stab wound or sutures for electrode placement and support. The barbed electrode is secured to the heart by gently pushing the tip into the myocardial tissue and the electrode is thereby secured to the myocardial tissue. The lead accepts a stiffening stylet for controlling the stiffness to aid in placement of the electrode within the myocardial tissue, and without the need for further insertion tool. The angle of the barbed electrode determines the specific application of the lead for ventricular or atrial pacing applications.

Abstract: Temporary adjustable bipolar lead including an inner lead and an outer coaxial lead. A self-sealing lead introducer head at a junction of the inner lead and outer lead provides for takeoff of the end of the outer coaxial lead. The inner lead is in slidable engagement with the outer lead through a hole in a diaphragm of the lead introducer head.

Abstract: A body implantable lead of the type having a lead body, at least one electrode carried by the lead body and tissue engaging tines extending at an acute angle from the lead body at a location adjacent the electrode. The present invention correlates the tensile stiffness of the lead body with the stiffness of the tines to optimize the tine holding force. The tines provide an adequate holding force to minimize unintentional lead dislodgements without requiring in an excessive force for intentional dislodgement of the lead for repositioning. Tine length and the angle at which they extend from the lead body are also discussed as affecting the probability of tine engagement with cardiac structure as well as having an effect on the holding force. In a preferred embodiment, the lead body has a spring constant (as defined herein) of 2.0 lb-in./10 in. or less and a tine stiffness (also defined herein) of less than 5.times.10.sup.-3 lb-in..sup.2.

Abstract: Tine protector which protects a plurality of outwardly angular extending tines from an electrode of a pacing lead. The tine protector includes four sides and a bottom where two of the opposing sides include a first round hole in one side, and a second round hole joined to a longitudinal vertical slit in the other side. The electrode frictionally engages into the first hole, and the other electrode or lead of the pacing lead frictionally engages down through the slit and into the second hole. The tines are protected by their close proximity to these two opposing sides.

Abstract: Non-fibrosing implantable lead apparatus for muscle stimulation, such as cardiac stimulation, comprising an electrode formed from a non-thrombogenic conductive material, a conductor, a conductor encapsulating structure formed from a non-thrombogenic insulating material and a lodging structure for holding said apparatus in a desired position.

Abstract: An implantable electrically actuated medical device having gas storage characteristics in which the device includes one or more electrochemical cells and an operative electric circuitry mounted in a metallic container, all of which are positioned in a mounting member made of a material which is highly permeable with respect to hydrogen gas, relatively impervious to liquid and which bonds well with an epoxy resin encapsulant coating over the device. The mounting member may be foamed as it is molded to provide voids therein for storage of gas or the recesses in which the electrochemical cells are mounted may be supplied with sponge-like pads for absorbing excess gas until it can permeate through the encapsulant to reduce pressure build-up within the device and prevent cracking of the casing.