Electrocardiographic Changes in Early Period after Planned Myocardial Revascularization

INTRODUCTION: To date, highly effective methods of myocardial protection have been developed, which are widely used in cardiac surgery. At the same time, the problem of perioperative myocardial infarction still exists and is one of the causes of adverse cardiovascular events and mortality, both at the hospital stage of treatment and in the long-term period. A factor leading to such a complication may be acute dysfunction of the coronary bypass graft, the timely detection and elimination of which will reduce the negative consequences of myocardial damage. The relevance of the study results from investigation of the relationship between the angiographic data and the character of ischemic changes on the electrocardiogram of patients with and without proven acute dysfunction of coronary bypass graft. AIM: Identification of the most pathognomonic electrocardiographic signs of dysfunction of coronary bypass grafts in the early postoperative period after planned myocardial revascularization. MATERIALS AND METHODS: The study included 196 (1.86%) of 10,550 patients operated for coronary artery disease in Chelyabinsk Center of Cardiovascular Surgery from 2011 to 2020, who underwent emergency angiography after planned coronary artery bypass graft surgery due to the appearance of signs of myocardial damage in the early postoperative period. Depending on the type of angiographic findings and the chosen treatment tactics, patients were divided to 3 groups. Group I (n = 86) included patients in whom angiography revealed defects in the area of large bypassed coronary arteries, of them 60 patients underwent endovascular treatment, and 26 patients underwent repeated open surgery. Group II (n = 33) consisted of patients in whom bypass graft dysfunction was noted, but, however, due to the small diameter or pronounced diffuse lesion of the bypassed coronary arteries, all the patients underwent conservative therapy. Group III included 77 patients in whom hemodynamically significant defects in grafts and native arteries were not identified. RESULTS: When studying postoperative electrocardiographic data, it was found that significant differences between the groups were obtained only in the occurrence of ventricular arrhythmias (P1–2 = 0.027; P2–3 = 0.01). As for other pathological electrocardiographic signs and their combinations, no statistical differences were found. CONCLUSIONS: An isolated electrocardiographic study in the early postoperative period does not permit to identify patients with dysfunction of coronary bypass grafts. It is necessary to develop a diagnostic algorithm, including instrumental and laboratory methods, for accurate diagnosis of myocardial ischemia caused by impaired graft function or pathological deformation of the coronary bed due to surgical procedures.