Abstract 11900: Quinidine as Salvage Therapy in Recurrent Monomorphic Ventricular Tachycardia

• Published in: Circulation (New York, N.Y.) Vol. 144; no. Suppl_1; p. A11900
• Main Authors: Larson, John D, Deshmukh, Amrish, Ghannam, Michael, Cunnane, Ryan, Ghanbari, Hamid, Latchamsetty, Rakesh, Crawford, Thomas, Jongnarangsin, Krit, Oral, Hakan, Morady, Fred, Bogun, Frank, Liang, Jackson
• Format: Journal Article
• Language: English
• Published: Lippincott Williams & Wilkins 16-11-2021
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.144.suppl_1.11900

IntroductionQuinidine is an effective therapy for a subset of polymorphic ventricular tachycardias and ventricular fibrillation (VF), however the efficacy of quinidine on scar related monomorphic ventricular tachycardia (MMVT) is unclear. HypothesisWe sought to assess the efficacy and adverse effects of quinidine in scar related MMVT. MethodsAll patients with MMVT treated with quinidine from 2009-2020 at a single VT referral center were reviewed. ResultsA total of 22 patients with MMVT and structural heart disease (age 66.7 ± 10.9, 20 males, 15 with ischemic cardiomyopathy, mean LVEF 22.2 ± 12.3%, 9 with left ventricular assist device (LVAD)) were treated with quinidine (14 patients on Gluconate formulation average dose 996mg±321, 8 patients on Sulfate formulation with average dose 1062mg±588). Quinidine was used in combination with other antiarrhythmics (AAD) in 18 (13 also on amiodarone). All patients previously failed >1 AAD (Amiodarone 100%, mexiletine 73%, sotalol 32%, other 32%) and 8 had prior ablations (median of 1.5). Quinidine was initiated in the setting of VT storm despite other AADs (6), inability to tolerate other AADs (4), or recurrent VT despite prior therapies (12). Ventricular arrhythmias requiring ICD or external shock occurred despite quinidine in 13 (59%) patients at a median of 26 (4-240) days after quinidine initiation. In patients with recurrent MMVT, VT cycle length increased from 359ms to 434ms (p=0.02). Treatment with quinidine was associated with an increase in QTc from 527ms (413-619) to 554ms (425-725) (p=0.004). Only 6 patients remained on quinidine at 1 year with recurrence of ventricular arrhythmias in all. Of the 6 patients on long term quinidine therapy, 3 patients had no shocks but did receive successful ATP within the first year. The following adverse effects were seenGI side effects (6), QT prolongation (2), rash (1), thrombocytopenia (1), neurologic side effects (1). One patient discontinued due to cost. ConclusionsQuinidine therapy has limited tolerability and efficacy when used in the management of amiodarone-refractory scar related MMVT. When possible, more effective therapies should be offered in patients with VT refractory to standard pharmacologic therapies.