Measurements, modeling, control and simulation - as applied to the human left ventricle for purposeful physiological monitoring.

Abstract Interdisciplinary engineering research effort (with medical interaction) in the measurement, modeling, control and simulation of the intact human left ventricle (involving closed-chest nontraumatic procedures) has been employed to physiologically monitor the heart and obtain its “state-of-health” characteristics. Of the four heart chambers, we have chosen the left ventricle to characterize cardiac performance: because it is the left ventricle that pumps blood into the circulatory system and hence its performance plays a key role in supplying energy to the body cells to enable them to sustain life. The importance and techniques for measurement of the left ventricular geometry are presented; the geometry is effectively displayed (on-line) to bring out the abnormalities in cardiac function. Mathematical modeling of the left ventricle is presented; the modeling, with the help of measurement data, enables us to determine the performance of the intact left ventricular muscle subject as reflected by, say, its oxygen consumption rate. A control system for the left ventricle is presented in order to incorporate the effects of dynamic changes in the circulatory system on the left ventricle's performance; the control system enables us to predict the effect of a certain physiological stress situation (such as exercise) on the left ventricle's performance.