Incidence, Risk Factors, and Outcome of Life-Threatening Ventricular Arrhythmias in Giant Cell Myocarditis

Background—Ventricular tachyarrhythmias are characteristic of giant cell myocarditis, but their true incidence, predictors, and outcome are unknown. Methods and Results—Our work involved 51 patients with giant cell myocarditis (35 women) aged 52±12 years. Their medical records were reviewed for history, results of laboratory and imaging studies, and occurrence of serious cardiac events, including life-threatening ventricular tachyarrhythmias. Sudden cardiac death (fatal or aborted) was the primary end point of our analyses, whereas the composite of sudden cardiac death and ventricular tachycardia requiring treatment constituted the secondary end point. Giant cell myocarditis presented as nonfatal ventricular tachyarrhythmia in 10 patients and as a fatal cardiac arrest in 1 patient. Overall, 14 of 50 patients suffered a sudden cardiac death during follow-up, with a cumulative incidence of 22% at 1 year and 26% at 5 years from presentation. The composite incidence of sudden cardiac death or ventricular tach...