Abstract 3237: Do Statins Reduce the Risk of Atrial Fibrillation/Flutter or Ventricular Tachyarrhythmias in Patients with an Implantable Cardioverter Defibrillator?
Background: In patients without implantable cardioverter-defibrillators (ICDs), statins have been shown to prevent atrial fibrillation and atrial flutter (AF/AFL). Whether it can prevent inappropriate ICD interventions due to AF/AFL or if it can suppress ventricular tachyarrhythmias (VT) is not known. This study investigated the impact of statin therapy on the incidence of AF/AFL and VT/VF requiring therapy among patients receiving an ICD.
Methods: We identified 1,445 consecutive patients referred to a single tertiary hospital receiving an ICD for primary (n=833) or secondary (n=612) prevention. Outcome measures include incidence of AF/AFL that initiated ICD therapy or VT/VF requiring ICD therapy. Cox proportional hazard regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CI).
Results: The population averaged 65.1 ± 13.0 years of age, 77.8% were male, the mean ejection fraction was 28.9 ± 14.4%, 66.6% with ischemic cardiomyopathy and 29.4% had history of atrial fibrillation. Over a mean patient follow-up spanning 874.5 ± 805.3 days, 13.8% had an AF/AFL event and 24.7% had a VT/VF event requiring ICD therapy. Seven hundred and fifty-nine (53%) patients were receiving a statin at the time of ICD implantation. While statin use was associated with a significant reduction in AF/AFL initiating ICD therapy [HR; 0.74 (95%CI 0.55– 0.99); p=0.04] (figure⇓); no reduction in the risk of VT/VF requiring ICD therapy was observed [HR; 0.97 (95%CI 0.79 –1.20), p=0.79].
Conclusions: Among a cohort with ICDs at high-risk for cardiac arrhythmias, statin therapy was associated with a reduction in AF/AFL requiring therapy, but not VT/VF.