Contrast-enhanced ultrafast computed tomography (CT) of the left ventricle was done in the long axis and short axis within one day of cardiac catheterization in 14 males with ischemic heart disease and a mean age of 58 years. Imaging was R wave-triggered at 58-msec intervals (13/level). Left ventriculography was performed in 30 degrees right anterior oblique (RAO) and 60 degrees left anterior oblique (LAO) caudal 12 degrees. CT left ventricular ejection fraction was measured using a modified Simpson's reconstruction of end-systolic and end-diastolic slices. Catheterization left ventricular ejection fraction was measured by area-length method. Six left ventricular segments (septal, apex, anterior, lateral, inferior, and posterior) were scored by different paired observers as follows: dyskinesis (-1), akinesis (0), moderate-severe hypokinesis (1), mild hypokinesis (2), and normal (3). Correlations of left ventricular ejection fraction for catheterization vs. long-axis CT and short-axis CT were r = .83 and r = .86, respectively. Seven of eight patients with transmural myocardial infarction were identified on CT by akinetic/dyskinetic segments. Eighty-four segments were scored. There was agreement (normal vs. abnormal) in 76 (90%). CT detected 47 normal segments vs. 51 by catheterization (92%), 11 akinetic/dyskinetic segments (92%), and 14 hypokinetic segments vs. 21 (67%). Wall motion scores between CT and catheterization differed by greater than 1 in 6 of 84 segments (7%). Therefore, ultrafast CT can accurately assess global and regional left ventricular function.