Left ventricular systolic time intervals during acute myocardial infarction.

Left ventricular systolic time intervals (LVSTI) were measured several times daily during 10 days in 47 patients with acute myocardial infarction without major complications. Left ventricular ejection time (LVET) and the interval between the beginning of depolarization and the aortic component of the second heart sound (Q-A2) decreased progressively during the first 72 hr. Shortening of Q--A2 and LVET was most marked in patients with heart failure and persisted till the end of the observation period.