Digitalis Therapy in Patients With Ventricular Tachyarrhythmias

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.

Digitalis Therapy and Risk of Recurrent Ventricular Tachyarrhythmias and ICD Therapies in Atrial Fibrillation and Heart Failure

Objective: This study sought to assess the impact of treatment with digitalis on recurrences of ventricular tachyarrhythmias in implantable cardioverter defibrillator (ICD) recipients with atrial fibrillation (AF) and heart failure (HF). Background: The data regarding outcomes of digitalis therapy in ICD recipients are limited. Methods: A large retrospective registry was used, including consecutive ICD recipients with episodes of ventricular tachyarrhythmia between 2002 and 2016. Patients treated with digitalis were compared to patients without digitalis treatment. The primary prognostic outcome was first recurrence of ventricular tachyarrhythmia at 5 years. Kaplan-Meier and multivariable Cox regression analyses were applied. Results: A total of 394 ICD recipients with AF and/or HF was included (26% with digitalis treatment and 74% without). Digitalis treatment was associated with decreased freedom from recurrent ventricular tachy­arrhythmias (HR = 1.423; 95% CI 1.047–1.934; p = 0.023). Accordingly, digitalis treatment was associated with decreased freedom from appropriate ICD therapies (HR = 1.622; 95% CI 1.166–2.256; p = 0.004) and, moreover, higher rates of rehospitalization (38 vs. 21%; p = 0.001) and all-cause mortality (33 vs. 20%; p = 0.011). Conclusion: Among ICD recipients suffering from AF and HF, treatment with digitalis was associated with increased rates of recurrent ventricular tachyarrhythmias and ICD therapies. However, the endpoints may also have been driven by interactions between digitalis, AF, and HF.