Aggressive Patch Augmentation May Reduce Growth Potential of Hypoplastic Branch Pulmonary Arteries After Tetralogy of Fallot Repair

Background Potential surgical strategies for hypoplastic branch pulmonary arteries (BPAs) during tetralogy of Fallot repair include (1) extensive patch augmentation to the hilum (PATCH), (2) limited extension arterioplasty to the proximal pulmonary artery (EXTENSION), or (3) leaving the native vessels unaugmented (NATIVE). We explored the effect of these strategies on reintervention and BPA growth. Methods From 2000 to 2012, 434 children underwent complete tetralogy of Fallot repair. Risk-adjusted parametric models were used to analyze the risk of BPA reintervention for (1) all children, (2) children with BPAs of 4 mm or smaller, and (3) children with BPAs of 3 mm or smaller. Repeated-measures analysis of more than 2,000 echocardiograms was used to characterize postoperative BPA growth and right ventricular pressure by using nonlinear mixed models. Results Overall survival (99% [3 deaths]) was excellent. The 10-year freedom from BPA reintervention was 84%. In risk-adjusted models (including baseline BPA z-score), PATCH had a decreased freedom from reintervention (73%; p p  = 0.07). For children with BPAs of 4 mm or smaller left in their NATIVE state, only ∼15% required reintervention. After adjustment for baseline BPA z-score, the time-related BPA growth was decreased ( p p  = 0.03) for the PATCH group. Conclusions Aggressive PATCH augmentation of hypoplastic BPAs improves the short-term geometry but may lead to late stenosis and higher rates of reintervention. Hypoplastic BPAs in tetralogy of Fallot tend (∼85%) to grow well without instrumentation.