Dipyridamole Does not Limit Myocardial Ischemia-Reperfusion Injury. A Double-Blind Randomized Placebo-Controlled Trial in Patients Undergoing Elective Coronary Artery Bypass Surgery


      Dipyridamole reduces ischemia-reperfusion injury in preclinical experiments and may be beneficial in patients undergoing coronary angioplasty, but its effect in patients undergoing coronary artery bypass graft (CABG) is unknown. We hypothesized that oral dipyridamole reduces myocardial ischemia-reperfusion injury in patients undergoing CABG surgery.

      Patients (or Materials) and Methods

      In a double-blind trial, 94 patients undergoing elective CABG were randomized to pretreatment with either dipyridamole slow-release (200 mg BID for 3 days) or placebo. The primary end point was plasma troponin I level at 6,12, and 24 hours after CABG. Secondary end points were the occurrence of bleeding, arrhythmias 24 hours postoperatively, the need for prolonged inotropic support, and prolonged intensive care unit stay. Seventy-nine patients (46 receiving placebo) were included in the per-protocol analysis of postoperative troponin I.


      Study arms did not differ with respect to age, sex, cardiovascular medication, cardiovascular risk factors, or aortic clamping time. Plasma troponin I concentration did not differ significantly between the placebo group and the dipyridamole-treated group: dipyridamole decreased overall troponin I by 3% (95% CI, –36 to 23). Secondary efficacy end points did not significantly differ between the 2 study arms. Clinically significant bleeding occurred in 4 patients treated with dipyridamole versus none receiving placebo (P > 0.1). In 1 of these 4 patients, a surgical explanation was found. Drain production did not significantly differ between the 2 treatment arms. Headache occurred in 22 patients taking dipyridamole versus 9 receiving placebo (P < 0.005).


      Dipyridamole before CABG did not significantly reduce postoperative troponin release. Therefore, oral dipyridamole does not prevent ischemia-reperfusion injury in CABG and should not be used for this indication.

      Disclosure of Interest

      None declared.