Predictors of mortality in patients with sustained ventricular tachycardias or ventricular fibrillation and depressed left ventricular function: Importance of β-blockade

To study prognostic factors in patients with sustained ventricular tachycardias (VT) or ventricular fibrillation (VF) complicated by left ventricular dysfunction, we evaluated the predictive value of demographic, clinical, and hemodynamic parameters for cardiac mortality and sudden cardiac death in 85 patients with VT or VF and left ventricular ejection fraction <0.45 (mean 0.27 ± 0.10). Patients underwent serial drug testing and received appropriate antiarrhythmic treatment, with amiodarone given as last-resort therapy. During a follow-up of 24 ± 13 months, 23 patients died of cardiac causes, and 18 of them died suddenly. Left ventricular ejection fraction ≤0.27 and amiodarone treatment were related to greater cardiac mortality and increased risk of sudden cardiac death, whereas β-blockade was associated with improved survival. In the multivariate model cardiac mortality was best predicted by a left ventricular ejection fraction ≤0.27, and absence of β-blockade and severe left ventricular dysfunction were the strongest predictors of sudden cardiac death. We conclude that severe left ventricular dysfunction predicts increased cardiac mortality and high risk of sudden cardiac death. Moreover, β-blocking treatment is associated with lower cardiac mortality and a reduced risk of sudden cardiac death in patients with sustained VT or VF and depressed left ventricular function. β-Blocking agents may therefore be an important addition to conventional antiarrhythmic treatment in patients with VT or VF and left ventricular dysfunction.