PROGNOSTIC-SIGNIFICANCE OF MAXIMAL PRECORDIAL ST-SEGMENT DEPRESSION IN RIGHT (V-1 TO V-3) VERSUS LEFT (V-4 TO V-6) LEADS IN PATIENTS WITH INFERIOR WALL ACUTE MYOCARDIAL-INFARCTION

This study examines whether patients with inferior wall acute myocardi al infarction (AMI) and maximal ST-segment depression in left precordi al leads are at higher risk for in-hospital mortality. The charts of p atients (n = 213) with inferior wall AMI and an initial electrocardiog ram that displayed peaked, tall T waves or ST-segment elevation with u pright T waves in inferior leads were reviewed, after excluding patien ts with inverted T waves in inferior leads (n = 75). ST-segment deviat ion from baseline was measured for all leads. Patients were classified into 3 types: I = no precordial ST-segment depression; II = sum of ST -segment depression in leads V-1 to V-3 equal to or more than the sum of ST-segment depression in leads V-4 to V-6; and III = maximal precor dial ST-segment depression in leads V-4 to V-6. Thirty-six patients (1 7%) died in the hospital. In-hospital mortality rates for patients wit h types I and II were 12% and 10%, respectively, compared with 41% for those with type III (p < 0.0001). Mortality rates in surviving patien ts were similar for all types up to 1 year after infarction. Multivari ate logistic regression models for in-hospital mortality by ST-segment depression type adjusted for age, previous AMI, diabetes mellitus, an d thrombolytic therapy revealed that type III pattern was a strong pre dictive factor for in-hospital mortality (odds ratio = 4.9, p = 0.0008 , 95% confidence interval 1.93 to 12.26). Thus, patients with inferior wall AMI and maximal precordial ST-segment depression in leads V-4 to V-6 are at high risk for in-hospital mortality.