Two-dimensional sector echocardiography allowed direct visualization of postinfarction ventricular septal rupture. Not only did this noninvasive technique allow visualization of the septal defect, but the distribution of the myocardial dysfunction was also readily determined. In the evaluation of seriously ill patient with complicated myocardial infarction, two-dimensional echocardiography might reliably be substituted for conventional left ventricular angiography.