Diagnosis of ventricular septal defect in acute myocardial infarction without cardiac catheterization.

Five patients with acute myocardial infarction and a systolic murmur suggestive of ventricular septal rupture or mitral regurgitation have been examined by external vascular isotope dilution curves over the chest after i.v. injection of 125I-hippuran. In three patients these isotope dilution curves showed signs of left-to-right shunting of blood, and subsequent autopsy demonstrated the presence of ventricular septal defect. In two patients there was no sign of left-to-right shunting, and these patients recovered.