# US 5,358,519 A · Muscle control and monitoring system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,358,519 A - Document ID: US5358519A - Status: Granted - Kind: A - Application number: 08/092,180 - Filed: 1993-07-15 - Granted: 1994-10-25 - Earliest claimed: 1989-12-06 - Assignees: Medtronic, Inc. - Inventors: Pierre A. Grandjean - Web page: https://patentgrep.com/patent/US5358519A ## CPC - A61M 60/148: in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices - A61M 60/161: mechanically acting upon the outside of the patient's blood vessel structure, e.g. compressive structures placed around a vessel - A61M 60/191: mechanically acting upon the outside of the patient's native heart, e.g. compressive structures placed around the heart - A61M 60/289: Devices for mechanical circulatory actuation assisting the residual heart function by means mechanically acting upon the patient's native heart or blood vessel structure, e.g. direct cardiac compression [DCC] devices - A61M 60/515: Regulation using real-time patient data - A61M 60/531: using blood pressure data, e.g. from blood pressure sensors - A61M 60/861: Connections or anchorings for connecting or anchoring pumps or pumping devices to parts of the patient's body - A61M 60/878: Electrical connections within the patient's body - A61M 60/882: Devices powered by the patient, e.g. skeletal muscle powered devices - A61N 1/36042: {of grafted tissue, e.g. skeletal muscle} - A61N 1/36557: {controlled by chemical substances in blood} - A61M 60/274: the inlet and outlet being the same, e.g. para-aortic counter-pulsation blood pumps - A61M 2205/054: with electrotherapy - A61M 2205/33: Controlling, regulating or measuring - A61M 2205/3303: Using a biosensor - A61M 2230/04: Heartbeat characteristics, e.g. ECG, blood pressure modulation - A61M 2230/205: partial oxygen pressure (P-O2) - A61M 2230/50: Temperature - A61M 2230/60: Muscle strain, i.e. measured on the user - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) ## 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. This indication of cardiac requirements may be used to vary skeletal muscle loading by adjusting duty cycle. The shortest term monitoring and control technique uses a temperature sensor to monitor efficiency skeletal muscle cardiac assist. Efficiency may be improved by adjusting the phase relationship between cardiac contraction and skeletal muscle stimulation. ## Claims ### Claim 1 A cardiac assist system for assisting a natural heart having ventricles which contract at a ventricular rate, said cardiac assist system adapted for coupling to a surgically prepared muscle responsively coupled to said heart and to a circulatory system, and said cardiac assist system comprising: a. control means adapted to be coupled to the heart and to the muscle for stimulating the muscle and for causing it to contract in synchrony with said ventricles of said heart; and b. means, coupled to said control means and adapted to be responsively coupled to the muscle, for monitoring a parameter indicative of a predetermined level corresponding to adequacy of circulatory support to the muscle. ### Claim 2 (depends on 1) The cardiac assist system according to claim 1 wherein said monitoring means comprises: a. means for sensing blood perfusion of the muscle; and b. means, responsively coupled to said sensing means, for storing data from said sensing means. ### Claim 3 (depends on 2) The cardiac assist system according to claims 2 further including means for telemetering out the data stored by said storing means. ### Claim 4 (depends on 2) A cardiac assist system according to claim 2 wherein said sensing means is an oximeter. ### Claim 5 (depends on 4) A cardiac assist system according to claim 4 wherein said oximeter is a two wavelength reflectance oximeter. ### Claim 6 (depends on 4) The cardiac assist system according to claim 4 further including means for telemetering out the data stored by said storing means. ### Claim 7 (depends on 1) The cardiac assist system according claim 1, wherein said monitoring means includes means for sensing a level of oxygen in the muscle. ### Claim 8 An assist system for assisting an organ, said assist system adapted for coupling to a surgically prepared muscle responsively coupled to said organ and to a circulatory system- has been inserted after "muscle". the assist system comprising: a. control means adapted to be coupled to the organ and to the muscle for stimulating the muscle and for causing it to contract in a predetermined sequence; and b. means, coupled to said control means and adapted to be responsively coupled to the muscle, for monitoring a parameter indicative of a predetermined level corresponding to adequacy of circulatory support to the muscle.