Dual Medical Therapy for Treatment of Arrhythmias in Cardiac Sarcoidosis

Anti-arrhythmics can be useful for ventricular arrhythmias in cardiac sarcoidosis (CS) that are refractory to immunosuppression. However, there is conflicting evidence on the efficacy of immunosuppression for treating arrhythmias in CS patients and a lack of data to support using immunosuppression alone as an initial strategy. The objective of this study was to assess for differences in arrhythmia burden over time with currently used immunosuppression and anti-arrhythmic regimens. Patients with CS and implanted cardiac devices were identified from a single-center registry. Study participants were retrospectively classified based on the medication regimen as follows: control (no therapy), immunosuppression, anti-arrhythmics, or dual therapy. Device interrogations were reviewed for premature ventricular contractions (PVCs), non-sustained ventricular tachycardia (NSVT), and device firings over time. Interrogations for 42 patients were reviewed over a mean period of 31 months. Regression analysis showed a significant decrease in the frequencies of PVCs (slope, -1.47; P = .04) and NSVT (slope, -0.05; P = .01) for patients on dual therapy compared to an increase or no change in the other groups. Across all patients, there was no difference between groups in the percentage of patients experiencing device firings. In a subset analysis of patients with implantable cardioverter-defibrillators for primary prevention, 6% on dual therapy required device firings compared to 43% and 40% on single or no therapy, respectively (P = .049, χ² = 6.02). In conclusion, patients on both immunosuppression and anti-arrhythmics had a reduction in PVCs and NSVT over time. Overall, there were no differences between groups in terms of device firings, except in a subset analysis of patients with no history of ventricular tachycardia.