Prevalence of prominent J waves in patients presenting with ventricular fibrillation without structural heart disease: a single-center study.

Association between sudden cardiac arrest and early repolarization (QRS slurring in the inferolateral leads) has drawn recent attention. We retrospectively assessed the prevalence of electrocardiographic J waves in 19 men aged 46.5±13.7 years who, between 1979 and 2011, were resuscitated after cardiac arrest due to ventricular fibrillation. There was no structural heart disease in this group. The J wave is an elevation of the QRS-ST junction of at least 0.1mV from baseline in the inferior or lateral leads, manifested as QRS slurring or notching. Eleven patients (age, 37.3±13.9 years) showed J waves in the inferior leads (n=8) or in both the inferior and lateral leads (n=3). Brugada syndrome was diagnosed in 5 patients (age, 46.4±15.7 years). The QRS complex was normal in the remaining 3 patients (age, 44.3±9.5 years). Ventricular fibrillation was induced by programmed ventricular stimulation with up to 3 extrastimuli from the right ventricular apex or outflow tract in 7 of the 10 J-wave syndrome patients tested, in all 5 Brugada syndrome patients, and in all 3 patients with a normal electrocardiogram. There appears to be an increased prevalence of J-wave syndrome among patients with a history of idiopathic ventricular fibrillation.