[A case of marked exercise-induced ST segment depression in anterior precordial leads with inferoposterior left ventricular aneurysm and significant stenosis of left anterior descending artery].

A 71-year-old man was admitted to a community hospital and diagnosed as having acute infero-posterior myocardial infarction. Severe ST segment depression occurred in anterior precordial leads with only 50 m walking, but he had no chest pain. He was then admitted to our hospital. Left ventriculography showed infero-posterior dyskinesis and aneurysm formation. Coronary angiography revealed triple-vessel disease including 90% stenosis at distal site of left anterior descending artery. Exercise thallium-201 myocardial scintigraphy by ergometer showed no filling defect in the anterior segment, though severe ST depression appeared in anterior precordial ECG leads. Infero-posterior segment showed persistent defect. We performed intravenous digital ventriculography at rest and during atrial pacing. Anterior wall motion during pacing was shown to be normal by amplitude and phase analysis. At the same time, the motion of the inferior wall was seen as abnormal and ST segment depression on anterior precordial leads appeared. We considered that in this case the anterior ST depression did not mean anterior myocardial ischemia but might be due to dyskinetic movement of the infero-posterior aneurysm.