TNFβ +250 polymorphism and hyperdynamic state in cardiac surgery with extracorporeal circulation

Introduction

We have investigated genetic and clinical factors associated with the hyperdynamic state (HS) after heart surgery with extracorporeal circulation (ECC).

Methods

We performed a prospective cohort study of consecutive patients who underwent elective heart surgery with ECC. The HS was defined as hyperthermia (>38°C), cardiac index (CI) >3.5 l/min/m² and systemic vascular resistance index (SVRI) <1,600 dynes × s/cm⁵ × m². The study included demographic variables, gene polymorphisms (A/G) of TNFβ +250, G/A-1082 of IL-10, polymorphism of IL-1 receptor antagonist, comorbidity, type of surgery, serum levels of IL-6, and postoperative course. We used the Pearson chi-square test or Fischer exact test, and the Student t test for univariate analysis, with forward stepwise logistic regression for multivariate adjustment.

Results

Eighty patients were studied, of whom 22 (27.5%) developed HS. The presence of allele G of TNFβ +250 polymorphism was associated with an increased incidence of HS (68% vs. 37%; P = 0.011). In the multivariate analysis, a longer duration of ECC, and the presence of the G allele, were associated with the development of HS.

Conclusion

The G allele of TNFβ +250 polymorphism, and prolonged extracorporeal circuit times, may favour the development of a hyperdynamic state after heart surgery with ECC.