Mid-Term Outcomes of Patients With Hypoplastic Left Heart Syndrome and Left Ventricle-Coronary Artery Fistula.

Infants with hypoplastic left heart syndrome (HLHS) with mitral stenosis/aortic atresia (MS/AA) have worse outcomes compared to other anatomic variants; this may be related to left ventricle-coronary artery (LV-CA) fistula. We reviewed patients with HLHS (MS/AA) referred to Boston Children's Hospital and managed from birth during 2008 to 2023 and compared those with and without LV-CA fistula defined angiographically. Among 90 patients, 58 (64%) had LV-CA fistula. In total, 66 (73%) of patients underwent surgical stage 1 palliation (S1P) and 22 (24%) underwent hybrid S1P; hybrid S1P was more common in the fistula group (36% vs 6%, p = 0.002). Probability of transplant-free survival at 1 year was 63% (95% CI 49%, 74%) for those with fistula and 78% (95% CI 60%, 89%) for those without. Over a median follow up of 4.3 years [IQR 0.5,7.9], 38 (42%) patients died or underwent transplant. In univariate analysis, lower GA (HR 1.31, 95% CI 1.16, 1.48), lower BW (HR 1.68, 95% CI 1.28, 2.19), initial hybrid S1P (HR 3.50, 95% CI 1.79, 6.84), and need for perioperative ECMO (HR 4.48, 95% CI 2.23, 8.99) were associated with increased risk of death/transplant (p <0.001 for all). The association of LV-CA fistula with death or transplant did not reach statistical significance (HR 1.83, 95% 0.89, 3.76, p = 0.10). Mortality remains high for children with HLHS (MS/AA) and while there was a trend toward worse transplant-free survival for children with LV-CA fistula compared to those without, factors other than LV-CA fistula may contribute.