RVOT Reconstruction in d-Transposition of the Great Arteries with Ventricular Septal Defect and Pulmonary Obstruction: Male-Female Differences in Clinical and Homograft Function

Abstract

ABSTRACTBackgroundThis study investigated male-female differences in clinical and homograft outcomes in dextro-transposition of the great arteries (d-TGA) patients, with ventricular septal defect (VSD) and pulmonary stenosis/atresia (PS/PA), who underwent right ventricular outflow tract (RVOT) reconstruction with a homograft.MethodsAll d-TGA with VSD and PS/PA patients receiving a homograft for RVOT reconstruction at our center from 1986 to 2021 were included. Time-to-event analyses were used for time-related clinical outcomes and mixed-effects models to characterize homograft function.ResultsTwenty-four patients (16 males) in whom 38 homografts were implanted over time were included. Median age at the first homograft implantation was 2.56 years [IQR: 1.26-11.31] and 2.06 years [IQR: 1.28-8.13] for males and females. Two early death (both males) and five late deaths (2 males) were observed. Twenty-two RVOT reinterventions (19/3 in males/females) occurred in follow-up (males/females:345.72/173.35 patient-years). The 10-year survival probability was 87.5% (95% CI: 67.3-100) for females and 87.1% (95% CI: 71.8-100) for males. Freedom from RVOT reintervention at 10-year was 87.5% (95% CI: 67.3-100) for females and 64.9% (95% CI: 47.9-88.0) for males. RVOT peak gradient increase rate was associated with body growth rate (7.27 [95% CI: 2.08-12.45], P=0.0133).ConclusionsSubstantial male-female differences in clinical and homograft outcomes were found in d-TGA with VSD and PS/PA patients receiving a homograft for RVOT reconstruction. Male patients had a higher RVOT reintervention rate and faster progression to homograft stenotic failure compared to females. Oversized homografts might benefit children for the strong association between rates of homograft stenosis and body growth.Clinical PerspectiveWhat is new?Male patients diagnosed with d-TGA, VSD, and PS/PA demonstrated a significantly higher rate of RVOT homograft reinterventions and a more rapid progression toward homograft stenotic failure when compared with their female counterparts.The male-female differences in clinical outcomes and homograft function may be attributed, in part, to the faster body growth observed in male children, especially given the strong association between rates of homograft stenosis and body growth.What are the clinical implications?For rapidly growing young children, opting for a suitably oversized homograft might serve as a more effective solution in reducing the rate of homograft stenotic failure.By exploring the relationship between homograft stenosis rate and individual body growth rate for each child, a personalized approach can be adopted during the homograft selection process, optimizing the sizing strategy for a better clinical outcome.