Correlation of electrocardiogram and vectorcardiogram with coronary occlusion and myocardial contraction abnormality.

Electrocardiograms and Frank vectorcardiograms were recorded in 156 consecutive patients with total occlusion of at least one coronary artery (on arteriography) and associated left ventricular contraction abnormality (on ventriculography). The angiograms and cardiograms were independently reviewed. In the presence of single vessel occlusion, appropriate vectorcardiographic diagnosis of myocardial infarction was determined in 118 of 156 cases (76 percent) compared with a lower electrocardiographic detection rate in 77 of 156 cases (49 percent). Findings diagnostic of two coexisting infarctions were observed in 71 percent of vectorcardiograms and 37 percent of electrocardiograms in 51 patients with double vessel occlusion and two areas of left ventricular dyskinesia. The vectorcardiographic detection rate was similarly superior to the electrocardiographic rate in the presence of subtotal coronary occlusion and myocardial asynergy in single (73 percent versus 53 percent) and double (53 percent versus 28 percent) vessel disease. The incidence rate of false positive diagnoses was 3 percent for electrocardiography and 4 percent for vectorcardiography. It is concluded that the vectorcardiogram is superior to the electrocardiogram in the diagnosis of obstructive coronary artery disease and left ventricular contraction abnormality.