Impact of intravenous exenatide infusion for perioperative blood glucose control on myocardial ischemia-reperfusion injuries after coronary artery bypass graft surgery: sub study of the phase II/III ExSTRESS randomized trial

{BackgroundThe aim of the study was to investigate whether intravenous (iv) infusion of exenatide, a synthetic GLP-1 receptor agonist, could provide a protective effect against myocardial ischemia-reperfusion injury after coronary artery bypass graft (CABG) surgery.MethodsA sub study analysis of patients >18years admitted for elective CABG and included in the ExSTRESS trial was conducted. Patients were randomized to receive either iv exenatide (1-h bolus of 0.05 mu gmin(-1) followed by a constant infusion of 0.025 mu gmin(-1)) (exenatide group) or iv insulin therapy (control group) for blood glucose control (target range 100-139mgdl(-1)) during the first 48h after surgical incision. All serum levels of troponin I measured during routine care in the Cardiac Surgery ICU were recorded. The primary outcome was the highest value of plasma concentration of troponin I measured between 12 and 24h after ICU admission. The proportion of patients presenting an echocardiographic left ventricular ejection fraction (LVEF) >50% at the follow-up consultation was compared between the two groups.ResultsFinally, 43 and 49 patients were analyzed in the control and exenatide groups, respectively {age: 69 [61-76] versus 71 [63-75] years; baseline LVEF<50%: 6 (14%) versus 16 (32%) patients; on-pump surgery: 29 (67%) versus 33 (67%) patients}. The primary outcome did not significantly differ between the two groups (3.34 [1.06-6.19] mu gl(-1) versus 2.64 [1.29-3.85] mu gl(-1) in the control and exenatide groups, respectively; mean difference (MD) [95% confidence interval (95% CI)] 0.16 [-0.25; 0.57]