Patch enlargement may not be a good strategy for treating tetralogy of Fallot with unbalanced pulmonary artery branches

Abstract OBJECTIVES Our goal was to determine the optimal strategy for managing tetralogy of Fallot (TOF) with unbalanced pulmonary artery (PA) branches by investigating the different effects of PA plasty on the development of hypoplastic PA (HPA). METHODS A single-centre, retrospective analysis was carried out to compare the outcome of different PA plasty methods on the development of HPA in patients with TOF with unbalanced PA branches. Size and balance of the PA branches were used to evaluate the outcome of PA plasty. RESULTS In the NATIVE group, 100% of the HPAs were well-developed and all PA branches became balanced, whereas in the PATCH and EXTENSION groups, the percentage of well-developed HPAs was 40% and 33%, respectively, and none of the PA branches were balanced. In addition, HPAs became atretic in 28% of the patients in the patch enlargement group. CONCLUSIONS For TOF with unbalanced PA branches, patch enlargement may not be a good treatment strategy, because it reduces the growth potential of HPA and even causes iatrogenic atresia. Leaving the HPA in the native state without patch enlargement may be a good strategy. A rare kind of tetralogy of Fallot (TOF) is characterized by unbalanced pulmonary artery (PA) branches: One PA branch is hypoplastic and the other is normal or hypoplastic, and the size of the hypoplastic PA (HPA) is no more than 1/2 that of the contralateral PA (CPA), especially when the HPA is only 2–3 mm (Fig. 1).