LONG-TERM FOLLOW-UP AFTER SUSTAINED MONOMORPHIC VENTRICULAR-TACHYCARDIA - CAUSES, PUMP FAILURE, AND EMPIRIC ANTIARRHYTHMIC THERAPY THAT MODIFY SURVIVAL

We analyzed the actuarial cardiac mortality rate of 295 consecutive patients with sustained monomorphic ventricular tachycardia who were referred to us between 1978 and 1988. Patients were divided into four groups: group I of 156 patients with coronary disease, group II of 55 patients with nonischemic left ventricular disease, group III of 65 patients with right ventricular disease, and group IV of 19 patients without detectable heart disease. Patients were treated empirically according to a prospective schema: (1) class I antiarrhythmic drugs, (2) in case of recurrence of ventricular tachycardia: amiodarone or beta-blockers, (3) in case of recurrence of ventricular tachycardia: drug combinations or surgery. The mean follow-up duration was 61 +/- 40 months after the first occurrence of ventricular tachycardia, and the clinical outcome was known in 67.5% of patients at 5 years. The actuarial mortality rates were considerably higher in groups I and II compared with those in groups III and IV (p < 0.01). The mortality rate was slightly higher in group I than in group II (p < 0.05). In groups I and II, acturial mortality rates were much higher when left ventricular ejection fraction was < 0.30 (p < 0.01). Comparisons between treatments showed no difference in actuarial mortality rates in patients with ventricular tachycardia and left ventricular ejection fraction > 0.30. By contrast, when left ventricular ejection fractions was < 0.30, a decrease in actuarial mortality rates in patients in groups I and II who were taking beta-blocking agents (p < 0.01) and an increase in those taking class I antiarrhythmic drugs (p < 0.05) were evidenced. Only patients with ventricular tachycardia and left ventricular disease, particularly those with left ventricular ejection fractions < 0.30, were prone to a significant rate of cardiac mortality after an attack of sustained monomorphic ventricular tachycardia. beta-Blocking agents seem preferable to class I antiarrhythmic drugs for treatment in these latter patients.