Computed tomography (CT) of the heart was performed using the JEOL Dynamic Scanner, which provides CT cardiac images with minimal radiation and within a short period of time. ECG-synchronized CT was undertaken at various phases of the cardiac cycle every 0.04 second. Approximately 30 minutes of scanning was necessary to obtain a series of CT images of one complete cardiac cycle. In contrast to 24 normal subjects, 38 patients with recent or remote myocardial infarction (MI) demonstrated hypokinetic, akinetic, or paradoxical movement of the ventricular segment corresponding to the MI sites predicted by ECG. The sequential cardiac area curve was useful in evaluating instantaneous changes of cardiac dimension, extent of ventricular contraction, and regional dyssynergy. ECG-synchronized CT studies using Somatom contrast dye enhancement in selected patients allowed sequential assessment of left ventricular cavity size and wall motion.