The ability of left ventricular angiography to detect regional ischemic dysfunction was assessed in 10 closed-chest dogs during the course of acute balloon occlusion of the anterior descending coronary artery. During the 2-minute period of occlusion, serial cineangiography revealed a sequence of wall motion abnormalities over the anteroapical region almost identical to that observed using directly implanted gauges. This sequence consisted of progressive reduction in regional systolic shortening with eventual replacement by systolic expansion. These changes preceded both electrocardiographic ST-segment and hemodynamic alterations, and were readily observed by gross subjective inspection of the cineangiograms, but with an intraobserver variability of 22%. Frame-by-frame motional analysis of the ventricular perimeter relative to its centroid of mass allowed more precise characterization of regional dysfunction. These data are consistent with previous studies demonstrating that regional wall motion abnormalities are both sensitive and specific markers of acute ischemia, and support the use of computerized left ventricular angiography for the quantitative assessment of clinical ischemic dysfunction.