Year: 2018
Type: letter
Abstract: We thank you for the opportunity to respond to the letter by Buratto et al. [1] regarding our article on the mid-term outcomes in unbalanced complete atrioventricular septal defect [2]. They raised the concern of survivor bias in our biventricular conversion/recruitment (BiVC/BiVR) cohort. We would like to point out that the reason we chose the date of BiVR or BiVC as the timing of entry into the study was because these patients, particularly BiVC patients, had their initial surgery at outside institutions. Therefore, obtaining accurate survival data for all unbalanced complete atrioventricular septal defect cases from these institutions was not feasible. Furthermore, for patients who were cared for from the neonatal period at our centre, we were careful to include all patients in whom an ultimate BiV circulation was planned in the BiVR group to avoid this bias. The premise of our article was to show that BiVC with or without BiVR could be achieved with a reasonably low mortality and morbidity, but with increased rates of reintervention. This is particularly important in certain high-risk groups such as trisomy 21 and heterotaxy, which poorly tolerate single-ventricle palliation. As depicted in our supplementary material, fig. S2, 13 of 57 (23%) patients with heterotaxy in the single-ventricle group died when compared with 3 of 32 (9%) in the BiVC/BiVR group and 4 of 101 (4%) patients in the primary BiV repair group. As we accrue more patients, we will be able to perform a matched analysis of the three cohorts in the future. As decision making in this complex cohort continues to evolve [3–6], longitudinal data on this cohort would provide valuable information to further elucidate therapy that is designed to meet the individual patient needs based on anatomical and physiological parameters. We agree that atrioventricular regurgitation remains the primary driver of reinterventions in unbalanced complete atrioventricular septal defect, whether it is single-ventricle palliation, primary BiV repair or BiVC/BiVR, as presented in table 6 of our article. Abnormalities in both valve morphology and ventricular morphology contributed to atrioventricular valve regurgitation in this patient population and therefore necessitate an individualized approach to repair.
DOI: 10.1093/ejcts/ezx500
Authors: Meena Nathan, Sitaram Emani, Pedro J del Nido
Institutions: Boston Children's Hospital, Harvard University
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2789758654