Abstract 16: Early Use of Aspirin is Critical for Improving Outcomes Following Systemic to Pulmonary Artery Shunting

Abstract

Objective: Systemic to pulmonary artery shunting (BT) is a common palliative procedure used in children with congenital heart disease. Despite the relatively simple nature of the procedure, the BT shunt procedure is associated with significant morbidity and mortality that is believed to be related perhaps to thrombosis of the artificial graft. The optimal postoperative anticoagulation regimen for this procedure is unknown. We compared the effectiveness of various anticoagulation regimens in patients undergoing BT shunt procedure, evaluating in particular the time of aspirin (ASA) initiation on BT shunt outcomes. Methods: The Pediatric Health Information System database (PHIS) was retrospectively queried (2000-2011) to identify patients (<30 days old) who underwent isolated BT shunts procedures. Postoperative anticoagulation regimens were categorized into: Heparin only, ASA and Heparin and ASA only regimens. The primary end point was mortality; secondary endpoints included the need for shunt revision, catheter-based investigation or intervention post procedure. The effect of aspirin supplementation on heparin regimen on the day of surgery and the day after was evaluated using GEE logistic regression to account for hospital clustering. All confounding factors were adjusted between groups. Cox proportional hazard analysis was performed in order to compare anticoagulation regimens after BT shunt surgery. Results: A total of 1746 patients were identified. Survival analysis revealed that ASA plus heparin is the best anticoagulation regimen after BT shunt surgery (p =0.001). Patients who survived to discharged, started ASA earlier than those died during hospitalization (mean day of start of 3.7±0.2 vs. 14.6±6.3 with interquartile range of 3 vs. 11 respectively, p= 0.001). Based on GEE modeling, administration of aspirin even on day one significantly decreased mortality rate (adjusted OR=0.21, CI 95%=0.04-0.97, p =0.04 compared to heparin only group). Conclusion: Our results demonstrate a critical role for ASA in lowering rates of mortality and complications in the immediate perioperative period after BT shunt surgery. Administration of ASA as early as first postoperative day can reduce the mortality rate for this common congenital heart procedure.