Predictive Value of the Systolic Time Intervals in Primary Myocardial Disease

¹ Cardiac Unit, Wentworth Hospital and the University of Natal, Durban, South Africa

The systolic time intervals were studied in 33 patients with primary myocardial disease and correlated with the underlying hemodynamic disturbance. Seven patients had associated functional mitral incompetence. Pre-ejection phase (PEP) correlated with mean left ventricular dp/dt (LVdp/dt), and left ventricular ejection time (LVET) correlated with stroke index (SI), cardiac index (CI), left ventricular end-diastolic pressure (LVEDP) and ejection fraction (EF). Patients with additional functional mitral incompetence had a shorter LVET and Q-A₂ than patients without mitral incompetence. The measurements were of value in predicting hemodynamic aberrations, and the predictive value could be enhanced by using two or more parameters simultaneously.