Successful Management of Patients With Pulmonary Atresia With Intact Ventricular Septum Using a Three Tier Grading System for Right Ventricular Hypoplasia

Background We sought to validate a simple grading scheme for right ventricular hypoplasia in determining suitability for a biventricular repair. Methods We reviewed the medical records for 106 patients with pulmonary atresia-intact ventricular septum (PA-IVS) treated between 1982 and 2001. Over this period, children were assigned to mild (>2/3 normal size, 23.7% of patients), moderate (1/3 to 2/3, 41.2%), or severe (1/3, 35.1%) right ventricular hypoplasia, and this grouping, along with severity of coronary anomalies (45% right ventricle to coronary fistulae, 16% with right ventricle dependent coronary circulation [RVDCC]), triaged children to eventual single ventricle (severe) or two-ventricle (mild or moderate) repair. Results Actuarial 10-year survival was 86.3% with mortality predicted by severe hypoplasia (odds ratio [OR] 12.9, p< 0.001), RVDCC (OR 15.0, p< 0.001), and non-Caucasian race (OR 10.7, p< 0.001). Multivariate analysis with a Cox proportional hazards model confirmed only RVDCC (risk ratio [RR] 10.9, p = 0.0009} and non-Caucasian race (RR 6.9, p = 0.007) as significant. Although not an independent risk factor for survival, the degree of hypoplasia was the most important determinant for definitive repair. Severe hypoplasia virtually precluded two-ventricle repair (OR 33.1, p< 0.001 by χ2 analysis) and was the strongest risk factor for a one-ventricle system (OR 78.7, p< 0.001). Actuarial survival after either repair was 91%, and no biventricular repair later converted to a Fontan system. Conclusions Surgical management of patients based on this three tier grade for right ventricular hypoplasia results in excellent survival and correctly predicts patients destined for eventual Fontan and biventricular repair.