Rational Approach to Surgical Management of Complex Forms of Double Outlet Right Ventricle with Modified Fontan Operation

Objective. Surgical alternatives to biventricular repair of complex forms of double outlet right ventricle (DORV) remain controversial. The available knowledge of the Fontan operation (FO) for children with this anomaly is limited. The aim of this report is to analyze the results and risk factors of the FO performed as an alternative to the biventricular repair of complex DORV. Methods. Between 1980 and 2007, 47 patients with complex forms of DORV underwent a modified FO. Concomitant defects included noncommitted, subpulmonary or multiple ventricular septal defects, anomalies of atrioventricular valves and/or caval veins, and ventricular hypoplasia. Thirty‐five of 45 patients (77%) have undergone a hemi‐Fontan and 35 patients (77%; 10 children without previous hemi‐Fontan) have had a completion FO without mortality or Fontan takedown. Risk factors for adverse outcomes were determined by multivariate analyses. Results. There were no early but six late deaths. The follow‐up period ranged from 1 year to 25 years (mean 10.0 ± 6.5). The actuarial survival was 93% at 1 year, 87% at 10, 15, and 25 years. Multivariate analysis identified preoperative left or common atrioventricular valve insufficiency (P = .001) and decreased left ventricular ejection fraction (<50%) (P = .02) as risk factors for late death and/or morbidity. The only risk factor for a late adverse outcome and poor functional status was increased preoperative pulmonary vascular resistance (>4.0 Woods units/m²) (P = .005). Conclusion. FO provides good early‐ and mid‐term results in the treatment of complex forms of DORV. The increased preoperative pulmonary vascular resistance was a significant negative risk factor for adverse outcome in this patient population.