The Burden of Prematurity on Early Outcomes after Neonatal Heart Surgery: A Systematic Review and Meta-Analysis

Objective Prematurity, defined as gestational age <37 weeks, is associated with adverse outcomes after neonatal cardiac surgery. This study evaluated the impact of late prematurity (34-37 weeks) on postoperative outcomes through a meta-analysis comparing term and late preterm neonates. Methods A systematic review identified studies comparing postoperative outcomes between term and late preterm neonates undergoing cardiac surgery. Subgroup analysis further compared early-term, full-term, and late-term neonates. Results Five studies including 7,611 neonates were analyzed, of whom 6,566 were term and 1,045 were late preterm. Most patients were derived from multicenter registries. Mean gestational age was 38.6 ± 0.4 weeks in term neonates and 35.4 ± 1.0 weeks in late preterm neonates. Transposition of the great arteries and Tetralogy of Fallot were similarly distributed between groups; however, truncus arteriosus, and genetic syndromes were more common among late preterm neonates. Early postoperative mortality and in-hospital length of stay were significantly higher in late preterm neonates compared with term neonates. Major postoperative complications and postoperative ECMO use were comparable. On subgroup analysis, early-term neonates had higher mortality and major complication rates than full-term neonates, while no significant differences were observed between full- and late-term neonates. Conclusions Prematurity remains an important risk factor for neonatal cardiac surgical outcomes. Late preterm neonates experience higher early postoperative mortality and prolonged in-hospital length of stay, supporting improved risk assessment, patient selection, and parental counseling.