Early outcomes from a new regional programme for the surgical management of hypoplastic left heart syndrome

Abstract

Outcomes for this new programme are comparable to reported outcomes demonstrating the feasibility of integrating a new complex procedure within an existing multidisciplinary unit handling large volumes of other complex neonatal work. Excellent outcomes can be achieved in standard-risk patients. Outcomes in the high-risk group may be improved by alternative approaches and rigorous case selection.

Impact of High-Risk Characteristics in Hypoplastic Left Heart Syndrome

“…We previously reported our approach to optimizing surgical case volume by having two attending surgeons participate in each Norwood operation with the lead operating surgeon taking the major decisions and integrating the clinical and organizational aspects of the procedure. 20 This practice has increased exposure to HLHS surgery for all surgeons, facilitated skills development, optimized outcomes, and minimized practice variation. Lower surgeon annual Norwood volume has been reported as an independent predictor of adverse outcomes by Newburger et al 15 in their report on six years of single ventricle reconstruction (SVR) trial.…”

“…We have applied Barron’s criteria 19 for classifying patients with HLHS as high risk in both this and our previous study. 20 There have been various other criteria suggested in the literature, 10,15,26 with most of them overlapping in definition and having similar findings except for ascending aortic size which remains an area of dispute.…”

“…We have previously reported our experience for the Norwood procedure from 2006 to 2011, where survival to stage II was 80%. 20 We have since embarked on programmatic changes that focus on a subset of distinct high-risk patients with a restrictive or intact interatrial septum (R/I-IAS) based on previously published modifiable risk factors. 19 The purpose of this study was to describe our outcomes of management of patients with HLHS at our centre with a focus on this high-risk subgroup.…”

Genomic and transcriptomic data analyses highlight KPNB1 and MYL4 as novel risk genes for congenital heart disease

“…The SNP rs11570508 associated with general CHD is located in a region that contains several genes linked to heart development, CHD and other cardiac phenotypes; MYL4, CDC27, GOSR2 and WNT9B (Goddard et al, 2017;Lahm et al, 2021;Orr et al, 2015;Sabour et al, 2018). A recent GWAS study on patients with anomalies of thoracic arteries and veins identified three significant SNPs within the GOSR2 locus in chromosome 17 close to rs11570508 (Lahm et al, 2021), and the chr17:45013271_T_C (rs17608766) variant in GOSR2 has been associated with a reduced aortic valve area (Córdova-Palomera et al, 2020) indicating importance of this locus in cardiac development.…”

“…The expression of MYL4 has shown to abnormally persist in ventricular tissue of individuals with CHD (England and Loughna, 2013), and the ventricular analog MYL3 is replaced by re-expression of MYL4 in failing and hypertrophied hearts, resembling a fetal remodeling pattern associated with ventricular dysfunction (Wang et al, 2019(Wang et al, , 2018. MYL4 loss-of-function variants have been associated with atrial cardiomyopathy and atrial arrhythmias such as atrial fibrillation (AF) (Gudbjartsson et al, 2017(Gudbjartsson et al, , 2015Orr et al, 2015;Peng et al, 2017), demonstrating that although previously not associated with CHD directly, its role in cardiac development and function is important, and thus, could be a plausible candidate gene for CHD.…”