Risk factors for fatal myocardial infarction after coronary bypass graft surgery

Background and objective The incidence and clinical impact of perioperative myocardial infarction during coronary artery bypass graft surgery vary gre atly depending upon the diagnostic criteria applied. Fatal perioperative my ocardial infarction has a less arguable diagnosis and clinical impact. The aim of this pa per is to fi nd out the risk factors for fatal myocardial in farction after coronary surgery. Methods Data from 1561 consecutive patients, who underwent coronary revascu larization during a 10-month period, have been retrospectively analysed. Af ter an univariate analysis for pre- and intraoperative risk factors, a mult ivariate model (logistic regression analysis) was settled. Results Preoperative use of subcutaneous/intravenous heparin, a heparin sen sitivity index <1.3 and need for a thromboendarterectomy of the left anteri or descending coronary artery are independent risk factors for fatal myocar dial infarction. The relative risk for fatal myocardial infarction was abou t 2 in the case of preoperative heparin use or heparin sensitivity index <1 .3 and 5.5 in the case of thromboendarterectomy of the left anterior descen ding coronary artery. Conclusions In patients undergoing coronary artery bypass surgery, preopera tive anticoagulation management with heparin may represent a risk factor fo r fatal myocardial infarction. Patterns of heparin resistance, whether or n ot due to heparin pretreatment. seem to be closely related to fatal myocard ial infarction.