Left ventricular dysfunction is a risk factor for sudden cardiac death in adults late after repair of tetralogy of fallot

Objectives The purpose of this study was to determine if left ventricular (LV) systolic dysfunction was also a predictor of sudden cardiac death (SCD) in adults late after repair of tetralogy of Fallot (TOF). Background Previous studies looking at risk factors for SCD in adults with repair of TOF have focused on the right ventricle (RV). Methods A retrospective chart review of patients assessed at the Toronto Congenital Cardiac Centre for Adults was performed. Twelve adult patients with repaired TOF and SCD were identified (SCD group). A total of 125 living adult patients with repaired TOF were randomly selected for comparison (control group). Results Patients with SCD were more likely to exhibit moderate or severe pulmonary regurgitation (92% vs. 51%, P = 0.02), have a history of sustained ventricular tachycardia (42% vs. 6%, p < 0.01), and have a QRS ≥180 ms (56% vs. 13%, P = 0.02). Moderate or severe LV systolic dysfunction was also significantly more common in patients with SCD than in the control group (42% vs. 9%, p < 0.01) with a positive predictive value of 29%. The combination of moderate or severe LV systolic dysfunction and QRS ≥180 ms had a positive and negative predictive value for SCD of 66% and 93%, respectively. Conclusions Moderate or severe LV systolic dysfunction is significantly more common in adult patients with repaired TOF and SCD. The combination of QRS ≥180 ms and significant LV systolic dysfunction has high positive and negative predictive value for SCD. The implication of the role of prophylactic antiarrhythmic implantable cardiac defibrillator insertion in these patients needs further elucidating.