Hybrid Computation of Left Ventricular Performance Using Noninvasive Technics.

Abstract : An automated method for a beat-to-beat analysis of Systolic Time Intervals (STI) has been developed using a unilateral hybrid computer system. Beat number, time of occurrence of beat, heart rate preejection period (PEP), preejection period index (PEPI), left ventricular ejection time (LVEF), left ventricular ejection time index (ETI), total electromechanical systole (Q-S2), total electromechanical systole index (Q-S2I), isovolumic contraction time (IVCT), and ratio of PEP to LVET were calculated from simultaneous recordings of electrocardiogram, carotid pulse, and phonocardiogram. The ability of automated analysis to provide beat-to-beat values extends the usefulness of this noninvasive method to evaluate left ventricular performance. (Author)