PMID: 33783481; DOI: 10.1093/ejcts/ezab141
Take Home Points:
- Patients who need an intervention to manage the pulmonary circulation at neonatal period carry the risk for death.
- TAPVC is no longer a risk for mortality in this study when it is addressed at the first palliation.
Commentary by Dr. Yasuhiro Kotani (Okayama, Japan), section editor of Congenital Heart Surgery Journal Watch:
A total of 53 patients with heterotaxy who underwent staged single ventricle palliation were included in this study. Thirty-five (66%) patients had a right ventricular dominance, common atrioventricular septal defect was present in 37 (70%) patients. Anomalous pulmonary venous drainage was present in 29 (55%) patients. Forty-six (86%) patients underwent first-stage palliation and, of these patients, there were 12 deaths (26%). A total of 41 patients, including those who did not have first palliation, received a bidirectional cavopulmonary connection (BCPC). There were 4 deaths after BCPC and 31 (58%) patients received total cavopulmonary connection (TCPC). Overall survival rate was 92% at 1 month, 74% at 1 year and 68% at 10 years. No patient died after TCPC. Independent risk factors for mortality in the multivariate Cox regression were a presence of restrictive pulmonary blood flow (HR 3.23; 95% CI 1.02–10.2; P = 0.05) and greater than mild atrioventricular valve regurgitation (HR 3.57; 95% CI 1.27–10.0; P = 0.02). Total anomalous pulmonary venous connection was not identified as a risk factor in this study. Mortality in patients with single ventricle and heterotaxy are high and this was often seen in the first 6 months of life.
Although previous studies showed TAPVC as a risk factor for death, this study demonstrated that TAPVC is no longer a risk when it is intervened from the first palliation which makes us think of alternating the timing of TAPVC repair. Most of deaths and reoperations occurred after first palliation but in other words, the patients do well once they overcome all adverse events during the first 6 months of life.
We all know that patients with heterotaxy do badly compared to other form of single ventricle. The study from Munich, Germany showed the consistent findings with high mortality and morbidity. In total of 53 patients, 46 patients had a first palliation, mainly to control the pulmonary blood flow. There were 7 early 5 late deaths, i.e., 26% of mortality in patients who had a first palliation. They stated the cause of death was cardiac in all patients. Although no details were shown, one can speculate that low systemic perfusion due to the imbalanced pulmonary blood flow was a main reason as they demonstrated restrictive pulmonary blood flow which need to be addressed as a risk factor for mortality. Seven patients had a balanced pulmonary circulation which did not require intervention at neonates and this is sub-group that does well regardless of interventions. They intervene TAPVC at the first palliation and only 2 of 14 (14%) had reintervention for PVO.
This excellent outcome of TAPVC contributed the finding that TAPVC was not identified as a risk for death. As the authors mentioned, it is quite difficult to manage the balance between pulmonary and systemic circulation at neonatal period, especially after surgical/catheter intervention. Although many factors, such as pulmonary blood flow and ventricular function/atrioventricular valve regurgitation are interactively affected to the pulmonary/systemic circulation, this study did not investigate the relationship. Therefore, the study focusing on this is necessary.