Electrocardiographic Diagnosis Of Critical Left Coronary Arterial System Stenosis

Coronary angiography is undoubtedly the gold standard diagnostic tool for coronary artery stenosis. However, if we could diagnose or highly suspect non-invasively critical and proximal stenotic lesions in the left coronary arterial system, this could salvage more myocardium and minimize the morbidity and mortality rate. There is no signal noninvasive variable indicating the culprit lesion in the coronary artery tree. However, in the emergency room we correctly suspected the presence of tight proximal stenosis in the left anterior descending artery just by following serial resting electrocardiogram done during chest pain and after relief of the pain. This was suggestive of Wellen's syndrome. In another patient presenting with chest pain and normal resting ECG an exercise treadmill test (ETT) was done. This test gave us a good clue for the presence of significant left main coronary artery stenosis and highlighted the significance of ST-elevation during ETT. Coronary angiogram supported our suggestion in the two cases. In view of the large area of the ventricle at risk, the recognition of such ECG patterns take on critical importance and provide important complementary information to that given by coronary angiogram and shorten the door-to-treat time. CASE REPORT NO. 1 & REVIEW A 55-year-old male Pakistani patient known to have hypertension and hyperlipidemia presented with typical anginal pain with no other symptoms. Electrocardiogram during chest pain showed sinus rhythm, normal axis, biphasic T-wave in V4-V5 minimal ST depression in V6. The pain was resolved then ECG was repeated and showed minimal ST elevation in V1 with inverted T wave in V2-V4, ST depression with inverted T in V5-V6 (fig. 1a,b). Figure 1 Figure 1 A & B: ECG on arrival to the emergency room with typical anginal pain and ECG 30 minutes after pain relief Half an hour later, chest pain recurred for a few minutes and then resolved. During the pain-free period, the ECG showed marked T-wave changes (fig.2a&b).