Clinical implications of precordial ST-segment depression in patients with inferior myocardial infarction : comparison between actue phases and exercise in chronic phase

The 61 patients with inferior myocardial infarction (IMI) were evaluated to investigate the clinical implications of precordial ST-segment depression (ST ↓≧1mm) during actue phase and exercose on chronic ohase. Electrocardiographic findings during actue phase and exercise in chronic phase were compared with results of left ventriculography (LVG) and coronary angiography (CAG) obtained from cardiac catheterization. Ejection fraction (EF) and regional ejection change (REC) were calculated from LVG. There were no significant differences between patients with and without ST ↓ during actue ohase in EF, REC and the extent of coronary artery disease. Patients with ST ↓ during exercise in chronic phase had more reduced EF(44±11% vs 53±8%, p＜0.01) and REC of diaphramatic segment (19±11% vs 26±12%, p＜0.05)and more incidence of multi vessel disease (55 vs 5%, p＜0.01). The presence of ST ↓ during exercise in chronic phase was not related to the presence of ST ↓ during acute phase. These results indicate that parients with ST ↓ during exercise in chronic phase rather than during acute phase have greater global and regional left ventricular and more extensive coronary artery disease.