990-51 Mechanisms and Predictors of Late Death in Asymptomatic Patients After Myocardial Infarction. A Prospective Study on Remodeling

Although left ventricular (LV) dilation after myocardial infarction (Mi) carries an adverse prognosis, it is unclear whether individual patients indeed die with progressive remodeling, and how dilation is related to death. We assessed 131 consecutive asymptomatic patients during 5 years after uncomplicated first myocardial infarction (Mi). In each, coronary angiography was performed at 4 weeks, LV end-diastolic (EDVI) volume (ml/m2), Lowngrade and QT-duration, corrected for heart rate (QTc, ms) were measured at 4 days, 4 weeks, 0.5,1.5, and 3 years by gated SPECT, Holter and 12-channel ECG, respectively. During an average follow-up of 59.7 months, 16 patients died (mortality 12.2%, median survival time of 30 months). Death was proceeded by progressive LV dilation (left figure) and occurred suddenly in 14 of 16 patients (88%). Extend and severity of ventricular arrhythmias, as indicated by a rise of Lawn-grade from 2.8±0.5 to 3.6±0.5, 5.0±0.4, 5.4±0.3 and 5.8±0.2 at 4 days, 4 weeks, 6 months, 1.5 and 3 years, respectively (p<0.00001), increased before death. This was associated with a rise of QTc from 457±6 at 4 days to 480±9 before death (p=0,01). In contrast, EDVI (left Figure) and Lown-grade did not rise and QTc even decreased (457±8, 456±8, 424±4, 414±5, 399±4) in survivors (p<0.05). Extend of LV dilatation correlated with severity of ventricular arrhythmias (right Figure). Non-survivors did not differ in drug therapy, electrolytes or initial coronary status and exercise tests were negative. These findings indicate that progressive LV dilatation (remodeling) may provide a proarrhythmic substrate for sudden death after Mi, which deserves more detailed analysis