Influence of allopurinol on cardiac complications in open heart operations

During cardiac operations, the heart is subjected to total ischemia and reperfusion, causing serious operative and postoperative complications such as arrhythmias, heart failure, and infarctions that may be partly due to free radical generation.Thus, allopurinol was tested to see if it could reduce cardiac complications during open heart operations.Ninety patients undergoing elective coronary artery bypass grafting were studied prospectively.Fortyfive patients were treated with allopurinol and 45 patients acted as controls.Treatment requiring arrhythmias in the allopurinol group was 6.6% compared with 33.3% he exact causes of arrhythmias are not clarified yet; T however, catecholamines and arrhythmogenic metabolites produced during reperfusion of the ischemic myocardium [l, 21 and a-receptor stimulation [3] are blamed.Recently, oxygen free radical generation during cardiac operations has been implicated in arrhythmias as well as in myocardial cell damage [4].Reperfusion arrhythmias and infarction may be a cause of death in humans.In support of an association between free radical production and arrhythmias, various studies have provided circumstantial evidence both in vitro and in vivo that allopurinol can reduce the vulnerability of the rat heart to reperfusion arrhythmias [5, 61.Other studies have shown improved cardiac function in ischemic animal hearts pretreated with allopurinol [7, 81.Some investigators have reported that allspurinol reduces infarct size in different experimental preparations [9, 101.The aim of this study was to determine if allopurinol treatment would alter cardiac complications in cardiac surgical patients. Material and Methods PatientsThis prospective, randomized trial involved 90 patients undergoing elective coronary artery bypass grafting.The study protocol was approved by the Ethics Committee of Gothenburg University, Sweden, on October 20, 1988, and conformed with the principles for human experimentation as defined in the declaration of Helsinki.Informed consent was obtained from each patient.The patients were randomized into two groups by flipping coins: 45 patients acted as controls and 45 patients were treated ~