Surgical outcome for patients with the mitral stenosis - aortic atresia variant of hypoplastic left heart syndrome

Objective: We sought to identify and characterize a subgroup of patients with hypoplastic left heart syndrome who might be at higher risk for stage I failure. Methods: From January 2001 through December 2006, all patients with hypoplastic left heart syndrome who underwent stage I palliation at Children's Hospital Bosto n were retrospectively reviewed. The subgroup with the mitral stenosis-aortic atresia variant was studied separately. We evaluated preoperative echocardiographic data, operative characteristics, and postoperative factors associated with death or the need for transplantation. The Kaplan-Meier method was used to assess survival. Results: Thirty-eight (23%) of 165 patients had mitral stenosis-aortic atresia. Hospital mortality or need for transplantation for patients with mitral stenosis-aortic atresia wa s significantly higher than for other anatomic subgroups (29% vs 7.9%, P =.002). Lef t ventricle-subepicardial coronary artery communications were present in 20 ( 53%) patients with mitral stenosis-aortic atresia and were associated with a significantly higher hospital mortality (50% vs 6%, P =.004). No difference in outcome wa s demonstrated between different sources of pulmonary blood flow. A longer cardiopulmonary bypass time (P =.02) and the need for postoperative extracorporeal membrane oxygenation support (P <.001) were associated with a higher mortality rate. Conclusions: With improved outcomes in the management of neonates with hypoplastic left heart syndrome, those with the mitral stenosis-aortic atresia variant and left ventricle-subepicardial coronary artery fistulae have emerged as a higher-risk subgroup for failure of stage I palliation. Further investigation is required, and a change in clinical management strategy for this particular subgroup might be warranted.