PO-714-01 RECURRENT VENTRICULAR ARRHYTHMIA IN PATIENTS WITH ACUTE MYOCARDITIS: INCIDENCE, CHARACTERISTICS AND POSSIBLE PREDICTORS

Implantable cardioverter defibrillator (ICD) implantation in patients experiencing ventricular arrhythmia (VA) in the setting of acute myocarditis (AM) is controversial. Guidelines on ICD implantation in these patients are sparse. For those presenting with VA during AM, data on the long-term recurrence of arrhythmia is needed to guide management. For patients presenting with VA in the setting of AM, this study will evaluate the recurrence rate of VA Multicenter retrospective analysis of patients diagnosed with AM presenting with VA. Diagnosis of AM was made based on clinical presentation, inflammatory or myocardial markers, cardiac MRI, endomyocardial biopsy and absence of significant coronary lesion on coronary angiogram or CT angiogram. Patients with history of myocardial infarction, cardiomyopathy or VA were excluded. Primary endpoint was the occurrence of recurrent VA. The study included 114 AM patients that presented with VA: Ventricular fibrillation-21, sustained Monomorphic VT (MMVT)-37, Polymorphic VT (PMVT)-4, and Non -Sustained VT (NSVT)-52. Recurrent VA occurred in 48/114 (42%); VF-9, MMVT-16, PMVT-2, and NSVT-21 during median follow up of 63 [8-130] months. There was no significant association found between patients’ age, sex, symptoms, medications, and recurrence of VA. The presence of late gadolinium enhancement (LGE) on cardiac MRI at presentation was more common among patients with recurrent VA (27/48 versus 22/66, p 0.02). Patients with recurrent sustained VA were more likely to have prolonged QRS duration (>110ms) and LV systolic dysfunction (LVEF<50%) during AM compared to those with recurrent NSVT or no recurrent VA (14/18 versus 32/69, p 0.03 and 17/25 versus 32/76; p 0.037). There was higher rate of recurrent VA among patients presenting with MMVT compared to those presenting with NSVT during AM (17/37 versus 8/52, p 0.002). Majority of patients with recurrent sustained VA during follow up had sustained VA during AM (19/27; 70.4%) Among patients presenting with VA in the setting of AM, 42% had recurrent VA. Patients with recurrent sustained VT were significantly more likely to have had prolonged QRS and LV systolic dysfunction during initial presentation. ICD implantation should be strongly considered in this patient population.