Echocardiographic determination of septal and left ventricular wall motion in the early hours of acute myocardial infarction.

Interventricular septal and left ventricular posterior wall excursions and velocities were determined by M-mode echocardiography in the early hours of acute myocardial infarction in 43 patients. In the group with anterior infarction, including 24 patients, the systolic septal excursion (SSE), systolic septal velocity (SSV), diastolic septal excursion (DSE), and diastolic septal velocity(DSV) were decreased (P less than 0.001). The posterior wall excursion during isovolumetric contraction (B-C) and the mean systolic posterior wall velocity (PWVmean) were also decreased (P less than 0.02). The posterior wall excursion during ejection (PWE) was not affected significantly. In the group with inferior infarction, including 19 patients, the B-C excursion was not significantly affected, but the PWE and PWVmean were diminished (P less than 0.001). The opposing healthy interventricular septum showed an increased movement-compensatory hyperactivity. These findings indicate that the acute myocardial ischemia which grossly affects the mobility of the myocardium can be detected and determined in the early hours by M-mode echocardiography.