Abstract: Apparatus and method for monitoring the performance of skeletal muscle used in a skeletal muscle powered cardiac assist system. The longest term monitoring is performed by an oxygen sensor which determines the adequacy of circulatory support to the skeletal muscle. An adequately supported skeletal muscle can offer the desired cardiac assistance chronically. Insufficient support indicates that the skeletal muscle will easily fatigue if adequate vascularization is not achieved. If the circulatory support is chronically insufficient, the risk of ischemia becomes high and additional surgical intervention may be required. A somewhat shorter term concern is the adequacy of the conditioning needed to render a fast twitch skeletal muscle useful in assisting the slow twitch myocardium. A pressure transducer is used to measure conditioning sufficiency. A third type of monitoring provides an indication of changes in cardiac requirements utilizing an activity sensor.

Abstract: One aspect of this invention relates to a temporary heart wire, and external connector therefore, and the combination of the two, wherein the distal end of the heart wire includes a temporary affixation coil (8) and distal pacing (2) and sensing (1) electrodes connected by means of a coaxial helicoidally wound cable (3) to a proximal electrode (7) and a breakaway needle (6) which also serves as a proximal electrode. The lead is adapted to be inserted into a disposable connector having a snap aperture element (19) for receiving the breakaway needle, and about which the needle is broken, as well as electrical contacts (17, 18) for contacting the proximal electrodes and adapted to be connected to a temporary external pacemaker. According to another aspect of this invention, there is provided a permanent bipolar nerve electrode which includes two electrodes (52), (54) adapted to be positioned along the nerve trunk (58).

Abstract: A temporary heart wire, and external connector therefore, and the combination of the two, wherein the distal end of the heart wire includes a temporary affixation coil (8) and distal pacing (2) and sensing (1) electrodes connected by means of a coaxial helicoidally wound cable (3) to a proximal electrode (7) and a breakaway needle (6) which also serves as a proximal electrode. The lead is adapted to be inserted into a disposable connector having a snap aperture element (19) for receiving the breakaway needle, and about which the needle is broken, as well as electrical contacts (17, 18) for contacting the proximal electrodes and adapted to be connected to a temporary external pacemaker. In an alternate embodiment, there is provided a permanent bipolar nerve electrode which includes two electrodes (52), (54) adapted to be positioned along the nerve trunk (58).

Abstract: Apparatus and method for monitoring performance of a skeletal muscle powered cardiac assist system. A chronically implantable temperature sensor is imbedded within the skeletal muscle. Muscle contraction and performance can be monitored by intramuscular temperature measurement. The temperature measurements are used by the implantable pulse generator of the cardiac assist system to maximize efficiency in the use of the skeletal muscle by optimizing timing of conditioning, maintenance, and stimulation pulses.

Abstract: An electrode and method of making same characterized by a biological material used as a substrate. The electrode is used primarily as a stimulation electrode, but could also be used to monitor electrical activity of neural tissues. The biological substrate is a chronically implantable material of treaterd human or animal tissue. The use of this material tends to prevent undue fibrosis and necrosis of the nerve tissue. An inner layer of a non-biologic dielectric may be used to increase to resistivity of the structure. Similarly an inner layer of shielding material may also be used.

Abstract: A method and apparatus for providing muscle stimulation in the field of Function Electrical Stimulation, particularly electrical stimulation to a muscle employed as a myocardial substitute. The Latissimus Dorsi muscular flap is divided into two parts to cover the surfaces of the heart and inserted into a thoracic cavity by means of a segmental resection of the second rib. After or before positioning the muscle in this fashion, first and second stimulating electrodes are threaded into the muscle at desired locations to effect contraction of the muscle around the heart upon application of electrical stimulating pulses between the two electrodes. Stimulating pulses having suitable parameters chosen to effect the desired functional contraction of the muscle are generated in synchrony with natural or stimulated heart contractions.