Aspirin Use Following the Arterial Switch Operation in the United States: Variability, Trends, and Perioperative Outcomes

BackgroundAspirin has the potential of offering coronary arterial protection from thromboembolism for patients following the arterial switch operation (ASO) but is used inconsistently and the benefits are unknown. We sought to discern trends and outcomes associated with the use of aspirin following the ASO.MethodsPatients undergoing the ASO were identified from the Pediatric Health Information System and divided into two groups: those who received aspirin post-ASO versus the nonaspirin group to evaluate trends, variations, and outcomes.ResultsA total of 6,350 ASO cases were identified (44 centers) of which 1,751 (27.6%) were in the aspirin group. Aspirin was started after a median postoperative duration of four days (interquartile range: 1-7). The aspirin group was more likely to have coronary anomalies (221/1,751[12.6%] vs 358/4,599 [7.8%], <i>P</i> < .001) and transposition of the great arteries + double outlet right ventricle (109/1,751 [6.2%] vs 313/4,599 [6.8%], <i>P</i> = .01). Aspirin use increased from 17% of case in 2004 to 39% in 2022. The number of centers using aspirin for ≥50% of their ASO patients increased from 2004 to 2008: 4 centers to 2019 to 2022: 15 centers (out of 32 centers with consistent participation) with a greater proportion of high-volume centers using aspirin. Overall, the aspirin group had lower in-hospital mortality (16/1,751 [0.9%] vs 155/4,599 [3.4%], <i>P</i> < .001) and similar rates of reoperation for bleeding (59/1,751 [3.4%] vs 203/4,599 [4.4%], <i>P</i> = .06) and postoperative extracorporeal membrane oxygenation (70/1,755 [4%] vs 195/4,599 [4.2%], <i>P</i> = .67). After adjusting for confounders, the mortality difference remained significant: odds ratio: 0.22 (95%CI: 0.10-0.47), <i>P</i> < .001.ConclusionConsiderable variation exists in the use of aspirin post-ASO with an overall increasing trend in aspirin use. In this study, the use of aspirin did not result in an increase in postoperative bleeding or other major adverse events. Prospective studies are needed to confirm the safety and benefits of aspirin.