56-79: Electrical storm as phenotypic manifestation of malignant repolarization syndrome

Abstract

A 46 y/o male was brought in our ED after 5 consecutive appropriate ICD discharges for ventricular fibrillation (VF), each of them preceeded by syncope. The ICD was implanted as secondary prevention after an episode of resuscitated VF. The patient denied any history of angina or dispnoea. He had a positive history for arterial hypertension and hypercholesterolemia. His family history was negative for sudden cardiac death or significant cardiovascular diseases. ECG at admission showed normal sinus rhythm with no conduction abnormalities but also a discrete J wave and a localized early repolarization aspect in the infero-lateral leads. Repeated lab tests ruled out acute myocardial necrosis and inflammation. Echocardiography showed no regional contraction abnormalities and a normal ejection fraction of the LV. However, cardiac MRT revealed a scar of the LV posterior wall, most likely post myocarditis. Coronary angiography showed normal epicardial coronary arteries. 12 lead ECG Holter monitoring revealed reproducibly spontaneous ST – segment elevations in the infero-lateral leads which occurred in the night, followed by early coupled PVC with a relatively narrow QRS complex. The patient denied any angina during these episodes. PVCs initiated repeated episodes of polymorphic VT degenerating subsequently into VF. Once the treatment with amiodarone was initiated, the number of PVCs decreased tremendously and no further appropriate ICD therapies were required.