Abstract: A method for detecting a quantitative measure of a physiologic state of a human myocardium or coronary artery. Implementations of the method detect the extent of change of myocardial electrical impedance from a mean baseline value to provide diagnosis of the extent of ischemia, stenosis, tissue rejection, and reperfusion and the effectiveness of cardioplegia and ischemia pre-conditioning as well as the general effectiveness of coronary bypass surgery as measured by post-operative reperfusion. Electrodes are attached to the myocardium, baseline measurements of the mean myocardial electrical impedance are stored and the variance of the myocardial electrical impedance and a baseline value of mean myocardial electrical impedance are computed from the baseline measurements and stored. Mean myocardial electrical impedance values are periodically measured between each electrode pair over an interval of time and stored.

Abstract: A method and apparatus for determination of cardiac function by monitoring left ventricular (LV) pressure and varying ventricular assist device (VAD) speed, utilizes a relationship of the end-diastolic LV pressure (LVEDP) to an estimate of LV work calculated from the LV pressure signal by the triple product (TP): dp/dtmax*HR*LVSP, wherein the slope of a regression analysis of the comparison of TP vs LVEDP is indicative of a patient's cardiac efficiency and analogous and comparable to preload recruitable stroke work as calculated from direct volume measurement of the LV, and of native cardiac function of a patient supported by a VAD, and related control systems for a VAD for controlling operation of the VAD according to the method.