Prognostic value of QRS fragmentation in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia.

Context: QRS fragmentation, including epsilon potentials, terminal activation delay and prolonged S wave upstroke, has been recently described as a diagnostic criterion of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D). Whether QRS fragmentation is a marker of recurrent ventricular tachycardia, primary ventricular fibrillation, implantable cardioverter defibrillator (ICD) discharge and sudden cardiac death in these patients is unknown.
Results: Three hundred and thirty-five patients (167 men, mean age 46.3 ± 14.6 years) with ARVC/D according to International Society and Federation of Cardiology/European Society of Cardiology (ISFC/ESC) criteria were analyzed retrospectively. Patients with complete and incomplete right bundle branch block were excluded from the analysis. At 6.3 ± 3.1 years mean follow-up, seven patients (0.02%) had died suddenly, 39 patients (0.13%) experienced recurrent ventricular tachycardia, 32 patients (0.1%) presented with primary ventricular fibrillation and 30 patients (0.1%) had recurrent ICD discharges. QRS fragmentation was significantly associated with arrhythmic events (P < 0.0000001 for the endpoint of sudden cardiac death, P < 0.01 for recurrent ventricular tachycardia, P < 0.0001 for primary ventricular fibrillation and P < 0.001 for recurrent ICD discharges, respectively).
Conclusion: QRS fragmentation predicts arrhythmic events in patients with ARVC/D. Further, properly designed prospective studies are warranted to confirm these findings.