Biotelemetry of cardiovascular hemodynamic measurements in miniswine.
A three-channel biotelemetry system has been designed and implemented for use in a chronically instrumented animal model of cardiovascular disease. A dual-channel ultrasonic transit-time micrometer allows monitoring of left-ventricular wall motion for the regions perfused by the left circumflex and left anterior descending coronary arteries. A third channel provides left ventricular blood pressure obtained from a high-fidelity blood pressure transducer implanted in the left ventricle. The biotelemetry system features a high voltage dc-dc converter for improved ultrasonic signal strength, a time-to-voltage converter that is highly immune to synchronization frequency variations, low power consumption (approx. 100 mW), small size (4 x 6 x 12 cm), and low weight (approx. 200 g). This three-channel system has enabled our laboratory to continuously monitor untethered animals for 24-h periods. Data obtained from this miniature biotelemetry system can be utilized to quantify myocardial oxygen demand and regional left-ventricular wall thickening.
Pitsillides
K F
KF
Department of Internal Medicine, University of California, Davis 95616.
Symons
J D
JD
Longhurst
J C
JC
D000818:Animals; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002908:Chronic Disease; D004195:Disease Models, Animal; D004452:Echocardiography / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D004867:Equipment Design / Q000592:standards; D005069:Evaluation Studies as Topic; D006439:Hemodynamics; D019736:Prostheses and Implants / Q000592:standards*; D013552:Swine; D013556:Swine, Miniature; D013686:Telemetry / Q000295:instrumentation / Q000379:methods / Q000592:standards*