Incidence and Outcomes of Pericardial Effusion After Congenital Heart Surgery

<b>Introduction:</b> Pericardial effusion (PCE) represents a significant postoperative complication following congenital heart surgery (CHS), contributing to more complex postoperative care and heightened morbidity. In this study, we aim to elucidate the risk factors contributing to PCE development post-CHS through analysis of data from a nationwide, multi-institutional database. <b>Methods:</b> Review of the Pediatric Health Information System Database from January 1, 2004, to December 30, 2023. All patients under the age of 18, who underwent a Society of Thoracic Surgeons benchmark procedure, were included. <b>Results:</b> A total of 66,695 surgeries were identified with 29,363 (44%) female, 35,084 (53%) non-Hispanic white, and median age at surgical admission of 5.1 [interquartile range: 2.0-14.1] months. Pericardial effusion occurred in 2,672 (4%) patients during the postoperative hospitalization, with the Norwood procedure having the highest incidence (245/2,726, 8.9%). Multivariable analysis revealed the Norwood procedure as having the highest adjusted odds of PCE (odds ratio [OR]: 2.34, 95%CI: 1.98-2.75, <i>P</i> < .001) when compared with isolated ventricular septal defect repair. Pericardial effusion was associated with a 16% (95%CI: 9.8-12.3, <i>P</i> < .001) increase in length of stay and increased mortality (OR: 1.84, 95%CI: 1.50-2.25, <i>P</i> < .001). Furthermore, 647 (1%) patients, out of 65,442 who survived to index hospital discharge, were readmitted due to PCE within 90 days of discharge. Fontan patients had the highest incidence of readmission (138/7,873, 1.7%) and increased adjusted odds for readmission (OR: 1.77, 95%CI: 1.37-2.28, <i>P</i> < .001). <b>Conclusions:</b> Incidence of PCE after CHS is low at 4%. However, certain procedures have an incidence as high as 8.9%. Pericardial effusion poses significant postoperative clinical challenges with increased mortality and resource utilization. Vigilant monitoring and targeted interventions in high-risk patients are essential for mitigating the impact of PCE on postoperative outcomes.