Abstract 15827: A Case of Ventricular Arrhythmia as Presentation for Cardiac Involvement of Polymyositis

Abstract

Introduction: Polymyositis is an autoimmune systemic disease which is characterized by chronic weakness and inflammation in skeletal muscle predominantly. Cardiac involvement has been reported and is a poor prognostic factor. Clinical course 61-year-old male with biopsy proven polymyositis with history of cardiac arrest secondary to ventricular fibrillation and dual chamber automatic implantable cardioverter defibrillator (AICD) implanted for secondary prevention. He had recurrent PVC-induced ventricular fibrillation causing AICD shocks. Eventually, he underwent electrophysiology study and successful ablation of PVC targeted to the basal lateral left ventricle.Transthoracic echocardiogram showed unremarkable systolic and akinetic basal inferolateral wall segment.He underwent PET-CT of myocardium which showed focal FDG uptake of the lateral basal left ventricular could indicate focal myocarditis.Endomyocardial biopsy did not show any evidence of myocarditis.Eventually he had recurrent rapid monomorphic ventricular tachycardia and was briefly placed on amiodarone. He was placed on immunosuppressive therapy managed by Rheumatology with etanercept, rituximab and IVIG. No recurrence of ventricular arrythmia has occurred since. Amiodarone has been discontinued. Discussion: Myocardial involvement of polymyositis is not uncommon and has been noted to increase morbidity and mortality.The most common reported manifestations include congestive heart failure, conduction abnormalities which can range from ventricular arrhythmia to complete heart block and coronary artery disease. ConclusionIt is very important to recognize polymyositis as a cause for ventricular arrhythmias in the right clinical setting as management with immunosuppressive therapy can decrease the burden in ventricular arrhythmias.