Does Preoperative Plasma Endothelin-1 Level Influences the Postoperative Events in Patients Undergoing Coronary Artery Bypass Grafting (CABG)? Revisiting Endothelin-1 Molecule in CABG Patients

Endothelin-1 (ET-1) is a powerful physiological vasoconstrictor release in response to endothelial injury. Increased synthesis of endothelin is associated with myocardial ischemia and reperfusion injury. The normal level varies between 0.2 and 18.5 pg/mL that maintains normal vascular homeostasis. We hypothesized that there exists a correlation between ET-1 and clinical outcome in patient undergoing elective coronary artery bypass grafting (CABG) surgery under cardiopulmonary bypass.Fifty-eight patients undergoing elective on-pump CABG were enrolled in the study. Blood sample for plasma ET-1 was taken before anesthesia induction. The median ET-1 level was 5 pg/mL (range: 0.6–30.33 pg/mL). The inotropic and intraaortic balloon pump requirement was significantly higher among patients having baseline ET-1 level more than 14.24pg/mL (p = 0.001in each case). A similar finding was observed in the duration of mechanical ventilation, intensive care unit stay, and duration of hospital stay (r = 0.68, p = 0.000; r = 0.58, p = 0.000; and r = 0.61, p = 0.000 respectively). The occurrence of complications was also more in individuals with higher baseline ET-1 level. The p-value was significant for occurrence infection, arrhythmia, renal and respiratory problems as observed in postoperative period by using Mann–Whitney U test.This study concludes that higher level of preoperative ET-1 levels correlates well to adverse clinical outcome in patients undergoing on-pump CABG surgery, so herein it can be used as a single independent parameter to predict postoperative outcome.