Arrhythmias in Patients With Heart Failure Prescribed Dofetilide or Sotalol

Background: Heart failure (HF) with reduced ejection fraction (HFrEF) is a risk factor for drug-induced arrhythmias. It is unknown whether HF with preserved ejection fraction (HFpEF) also increases the risk. Objectives: The purpose of this study was to determine if the risk of ventricular tachycardia (VT) and sudden cardiac arrest (SCA) is increased in patients with HFpEF prescribed dofetilide or sotalol. Methods: Using Medicare claims and pharmacy benefits from 2014 to 2016, we identified patients taking dofetilide or sotalol and non-dofetilide/sotalol users among 3 groups: HFrEF (n = 26,176), HFpEF (n = 33,304), and no HF (n = 580,249). Multinomial propensity score matching was performed. We compared baseline characteristics using Cochran-Mantel-Haenszel statistics and standardized differences, and tested associations of VT and SCA among dofetilide/sotalol users and those with HFpEF, HFrEF, or no HF using a generalized Cox proportional hazards model. Results: VT and SCA occurred 166 (10.68%) and 16 (1.03%) of 1,554 dofetilide/sotalol users with HFpEF, 543 (38.76%) and 40 (2.86%) of 1,401 dofetilide/sotalol users with HFrEF, and 245 (5.06%) and 13 (0.27%) of 4,839 dofetilide/sotalol users without HF. Overall VT risk was increased in HFrEF and HFpEF patients (HR: 7.00 [95% CI: 6.10-8.02] and 1.99 [95% CI: 1.70-2.32], respectively). The risk of VT in patients prescribed dofetilide/sotalol was increased in HFrEF and HFpEF patients (1.53 [95% CI: 1.07-2.20] and 2.34 [95% CI: 1.11-4.95], respectively). While the overall SCA risk was increased in HFrEF and HFpEF patients (5.19 [95% CI: 4.10-6.57] and 2.53 [95% CI: 1.98-3.23], respectively), dofetilide/sotalol use was not associated with an increased SCA risk. Conclusions: In patients with HF who are prescribed dofetilide or sotalol, the risk of VT, but not SCA, was increased.