Left ventricular performance in coronary artery disease by systolic time intervals and echocardiography.

Determinations of systolic time intervals and echocardiographic measures of left ventricular performance were made in twenty-five normal subjects and 37 patients who had convalesced from a previous transmural myocardial infarction. On group analysis the patients with previous myocardial infarction demonstrated significant differences from the normals in each of the noninvasive measures. Among the noninvasive measures the PEP/LVET and deltaD% proved to be the most sensitive indicators of left ventricular dysfunction. Deviations from the normal range in PEP/LVET and deltaD% occurred in 65% to 70% of patients asymptomatic for dyspnea and fatigability (20 patients) and in 85% of patients asymptomatic for angina pectoris (13 patients). Neither the presence of phonocardiographically documented S3 or S4 or the finding of an abnormal C/T ratio on standard chest x-ray reliably detected patients with abnormal left ventricular performance. Among 26 patients studied by coronary arteriography, abnormal left ventricular performance by PEP/LVET and deltaD% occurred in less than 30% of those with obstruction (70% or greater) of one coronary artery and in over 80% of those with obstruction of two or three major arteries. A close correlation existed between the level of left ventricular performance measured by the PEP/LVET and the deltaD% (r = 0.93). These studies document the high degree of sensitivity of the noninvasive measures and demonstrate their superiority over clinical methods for detecting abnormal left ventricular performance in patients with previous myocardial infarction.