THE DIAGNOSIS OF VIABLE MYOCARDIUM BEFORE SURGERY AND ASSESSMENT OF THE DYNAMICS OF ITS RECOVERY AFTER CARDIAC REVASCULARIZATION

The continuing high rates of morbidity, hospitalization and mortality of the population with coronary heart disease, despite the search for new diagnostic and treatment methods, indicate the urgency of the problem to date. Patients with coronary heart disease require an individual comprehensive approach due to the nature and severity of atherosclerotic lesions, the presence of a potentially viable myocardium, and the volume and severity of its hibernation. The introduction of the method of stimulation of extracardial neoangiogenesis into clinical practice has significantly expanded the treatment options for patients with diffuse coronary artery disease. The article presents data on preoperative visualization of a viable myocardium in patients with severe atherosclerotic lesions of the coronary bed, as well as the dynamics of its recovery in the postoperative period, depending on the performed surgical revascularization method.Materials and methods. The prospective, randomized study included data from 140 patients with coronary artery disease and diffuse coronary artery disease who underwent myocardial revascularization from 2016 to 2023 at the Department of Cardiovascular Surgery at the Moscow Institute of Thoracic and Cardiovascular Surgery. St. George’s Federal State Budgetary Institution “National Medical and Surgical Center named after N.I. Pirogov” of the Ministry of Health of the Russian Federation. Group I (n = 71) – complex revascularization; group II (n = 69) – isolated coronary bypass surgery. The results of gated-SPECT of the myocardium and echocardiography were evaluated early (10-14 days) and 6-12 months after surgery. Segmental analysis of changes in myocardial perfusion and contractility was performed. The main variants of perfusion-functional compliance were evaluated. The primary endpoint is a change in the volume of the hibernated myocardium during the entire follow-up period. Secondary endpoints are the dynamics of regional perfusion and contractility; changes in the left ventricular ejection fraction.Results. The volume of the hibernated left ventricular myocardium in the early postoperative period decreased from 29[20;35]% to 17[10;25]% in group I (p<0.0001) and from 27[20;34]% to 18[10;26]% in group II (p<0.0001). In the long-term postoperative period (6-12 months), the volume of viable myocardium was 10[5;12]% (group I) and 21[14;25]% (group II) (p = 0.0002). Three degrees of hibernation were distinguished depending on the dynamics of contractility recovery: mild (complete restoration of the “sleeping” myocardium in the early postoperative period, moderate (complete recovery within 6-12 months), severe (partial improvement of contractility within 12 months). After 12 months, the left ventricular ejection fraction was 56[54;59]% (group I) and 53[51;57]% (group II) (p<0.0001).Conclusion. The assessment of myocardial viability is an important criterion for choosing treatment tactics for patients with coronary artery disease, especially those with diffuse coronary artery disease. The addition of coronary bypass surgery to stimulate extracardial neoangiogenesis makes it possible to increase the restoration of the function of a larger volume of the hibernated myocardium and significantly improve the long-term results of complex treatment of patients.