Early mortality in infants born with neonatal-operated congenital heart defects and low or very-low birthweight: Systematic review and meta-analysis

Abstract

Congenital heart defects (CHD) are the most frequent congenital anomalies. Mortality outcomes of children with isolated (i.e. not associated with chromosomal anomalies, malformations from other systems or syndromes) neonatal operated CHD (NOCHD) born low or very-low birthweight (LBW and VLBW; birthweight < 1500 and < 2500 g, respectively) remain ambiguous. To summarize early mortality outcomes of infants born with NOCHD and LBW or VLBW. We searched Medline and Embase (from inception until May 2022) and included studies that evaluated early mortality in infants born with NOCHD and LBW or VLBW. Risk of bias was assessed using the Critical Appraisal Skills Programme cohort checklist. Meta-analysis involved use of random-effects models. We explored variability in mortality across birthweight subgroups, NOCHD subtypes, and study designs. Registration: PROSPERO, CRD42020170289. From 2,035 reports, we included 23 studies in qualitative synthesis, and the meta-analysis included 11 studies (1,658 CHD cases). Risk of bias was deemed low in 4/11 studies. Overall, mortality before discharge or within one month after surgery was 32% (95%CI 23–40%, I2 95%). Early mortality varied between VLBW and LBW infants (45% vs. 13%; P = 0.009) and across CHD subtypes (hypoplastic left heart syndrome 50%, total anomalous pulmonary venous return 47%, transposition of the great arteries 17%, coarctation of the aorta 14%; P = 0.03). Mortality was higher in population-based studies (45% vs. 7%; P = 0.003). One-third of infants born with NOCHD and LBW or VLBW will die within 30 days after surgery. Mortality varies substantially across infant and study characteristics.