Relation or Influence of RVOTO in the Inflammatory Response to Reoxygenation in Patients with Tetralogy of Fallot

Abstract

Background: This study evaluated differential inflammatory response to cardiopulmonary bypass reoxygenation in tetralogy of Fallot repair. Methods: We performed a retrospective study at a cardiovascular center from 2012 to 2018, including 500 patients aged 1 week-18 years who received complete repair of tetralogy of Fallot. Patients were grouped according to tertiles of preoperative RVOT gradient on echocardiography into mild, moderate, and severe stenosis. We measured the highest perfusate oxygenation (PpO2) during aortic occlusion as independent variable. Primary outcome was systemic inflammatory response syndrome (SIRS) within 7 days postoperatively or the time of death or discharge. Results: Overall, rate of SIRS was 24.2% without significant differences among three groups (P > 0.05). Older age, male, and smaller indexed left ventricular end-diastolic volume is independent risk factor of SIRS. There were significant interactions between RVOT stenosis and PpO2 on SIRS (P interaction = 0.011): higher PpO2 was associated with a greater SIRS risk among combined moderate and severe stenotic children (OR 1.463 95%CI [1.080, 1.981] per-SD increase, P = 0.014) but not among mild stenotic children (OR 0.900 [0.608, 1.333] per-SD increase; P = 0.600), independent of covariates. Conclusion: The association of PpO2 with SIRS was modified by RVOT obstruction severity in tetralogy of Fallot repair. (Clinical Trials gov: NCT03568357)