Digitalis Therapy in Patients With Ventricular Tachyarrhythmias

Abstract Objective: The study sought to assess the prognostic value of treatment with digitalis on long-term prognosis in patients with ventricular tachyarrhythmias and atrial fibrillation (AF) and/or heart failure (HF).Background: Data regarding outcome of digitalis therapy following ventricular tachyarrhythmias is limited.Methods: A large retrospective registry was used including consecutive patients with episodes of ventricular tachycardia (VT) or fibrillation (VF) from 2002 to 2015. Patients treated with digitalis were compared to patients without. The primary prognostic outcome was all-cause mortality at three years, secondary endpoints comprised of a composite arrhythmic endpoint (i.e., recurrences of ventricular tachyarrhythmias, sudden cardiac death) and cardiac rehospitalization. Kaplan Meier, multivariable cox regression and time trend analyses were applied for statistics.Results: A total of 831 patients were included (20% treated with digitalis and 80% without). At three years, digitalis treatment was not associated with all-cause mortality in patients with ventricular tachyarrhythmias (24% vs. 21%, log rank p=0.736; HR=1.063; 95% CI 0.746-1.515; p=0.736). However, digitalis therapy was associated with increased risk of the composite endpoint (38% vs. 23%; log rank p=0.001; HR=1.719; 95% CI 1.279-2.311; p=0.001) and cardiac rehospitalization (31% vs. 18%; log rank p=0.001; HR=1.829; 95% CI 1.318-2.538; p=0.001) at three years, which was still evident within multivariable Cox regression analyses. Finally, digitoxin was associated with worse prognosis than digoxin.Conclusion: Digitalis therapy was not associated mortality in patients with ventricular tachyarrhythmias, but with increased risk of the composite arrhythmic endpoint and cardiac rehospitalization at three years.