OBJECTIVE: Risk factors for mortality after neonatal cardiac surgery have been seldom studied. We sought to identify contemporary risk factors for mortality and the impact of surgical technical performance on surgical outcomes after neonatal cardiac surgery. METHODS: We conducted a matched case-control study comparing 56 neonates who died after cardiac surgery (2002-2008) with 56 survivors matched by surgical procedure and year of surgery. Surgical efficacy for repair or palliation was graded using a reliable simple surgical technical score. Patient and surgical characteristics were compared for the survivors and nonsurvivors using paired analyses. RESULTS: There was no significant difference between patients who died and their matched controls in terms of age, Aristotle score, Risk Adjustment in Congenital Heart Surgery-1 category, and single versus biventricular repair. When compared with survivors, patients who died were more likely to be premature (41% vs 5%, P < .001), to weigh less than 2.5 kg (25% vs 9%, P = .05), and to have inadequate surgical repair or palliation (55% vs 9%, P < .001). Cardiopulmonary bypass time was longer for the patients who died (median, 159 vs 133 minutes, P = .002). Highest postoperative lactate (median, 9.0 vs 6.0, P < .001), use of extracorporeal membrane oxygenation (71% vs 13%, P < .001), and reoperation during the same admission (75% vs 2%, P < .001) were also associated with death. In multivariable analysis, inadequate surgical repair or palliation (odds ratio, 11, P = .02) and need for postoperative extracorporeal membrane oxygenation (odds ratio, 5.1, P = .009) were the only risk factors associated with hospital death. CONCLUSIONS: Our study highlights the need for optimal technical performance to minimize neonatal deaths. This has important implications when sustaining or developing a pediatric cardiac program.