PREDISPOSING FACTORS AND PROGNOSTIC VALUE OF SUSTAINED MONOMORPHIC VENTRICULAR-TACHYCARDIA IN THE EARLY PHASE OF ACUTE MYOCARDIAL-INFARCTION

Objectives. The purpose of the study,vas to analyze the factors that f avor the occurrence of sustained monomorphic ventricular tachycardia i n the early phase (< 48 h) of acute myocardial infarction and to estab lish its prognostic implications, Background. Sustained monomorphic ve ntricular tachycardia early in the course of an acute myocardial infar ction is an uncommon arrhythmia, and its significance has not been spe cifically studied, Methods. The clinical characteristics and prognosis of sustained monomorphic ventricular tachycardia were studied in 21 ( 1.9%) of 1,120 consecutive patients admitted to the coronary care unit with a diagnosis of myocardial infarction,Results. Patients with sust ained monomorphic ventricular tachycardia had a larger infarct on the basis of peak creatine kinase, MB fraction (CK-MB) isoenzyme activity (435 +/- 253 IU/liter vs. 168 +/- 145 IU/liter, p < 0.001) and higher mortality rate (43% vs, 11%, p < 0.001), By logistic regression analys is, independent predictors of sustained monomorphic ventricular tachyc ardia were CK-MB (odds ratio [OR] 11.8), Killip class (OR 4.0) and bif ascicular bundle branch block (OR 3.1), Moreover, sustained monomorphi c ventricular tachycardia was itself an independent predictor of morta lity (OR 5.0). Compared with patients with ventricular fibrillation, t hose with sustained monomorphic ventricular tachycardia had a worse Ki llip class (Killip class >I: 63% vs, 30%, p < 0.05), higher CK-MB acti vity (430 +/- 260 IU/liter vs, 242 +/- 176 IU/liter, p < 0.01) and hig her arrhythmia recurrence rate (31% vs, 4%, p < 0.01), During the foll ow-up period, 5 (42%) of 12 survivors in the sustained monomorphic ven tricular tachycardia group died of cardiac-related causes, Recurrence of ventricular tachycardia Has seen in two patients (17%). Conclusions . Sustained monomorphic ventricular tachycardia during the first 48 h of myocardial infarction is a sign of extensive myocardial damage and an independent predictor of in-hospital mortality. (C) 1996 by the Ame rican College of Cardiology