Clinical relevance of eNOS T-786C polymorphism for hospital mortality and morbidity in cardiac surgical patients

Abstract

Aim. The endothelial nitric oxide (eNOS) gene T-786C polymorphism may influence as a genetic risk factor cardiovascular diseases and shows association with cardiovascular mortality. We hypothesized that this polymorphism may lead to increase mortality and morbity after cardiac surgery with cardiopulmonary bypass (CPB). Methods. In 500 patients who underwent cardiac surgery with CPB we investigated the eNOS T-786C polymorphism by DNA-sequencing. The patients were grouped according to their genotype in three groups (TT, TC, and CC). Results. The overall genotype distribution of T-786C polymorphism was TT=41.60/0, TC=51.2%, and CC=7.2% respectively. The groups did not differ in age and gender. No significance was shown in preopertive risk factores, excluding perpheral disease (P=0.03). No difference was shown in Euroscore, APACHE II, and SAPS II. The usage of norepinephrine (P=0.03) and nitroglycerine (P=0.01) was significant higher in TC allele carrier. The mortality was quite uniform across elective and urgent subgroup. However, we found a significant difference concerning mortality and emergency cardiac procedures in homozygous C-allele carrier (P=0.014). Conclusion. The present study demonstrates that this polymorphism contributes to a higher prevalence of postoperative mortality after emergency cardiac surgery. Thus, the eNOS T-786C polymorphism could serve as a possibility to differentiate high risk subgroups in heterogeneous population of individuals with cardiac diseases who need cardiac surgery with CPB.