Introduction. Coronary hagiography revealed 70%-prevalence of multivessel coronary lesions. Chronic coronary occlusion (CCO) occurs in approximately 20 % of patients with coronary heart disease. Endovascular recanalization of CCO is associated with technical difficulties and the risk of complications. In this regard, patients with CCO rarely undergo revascularization, which leads to incomplete myocardial revascularization.Materials and methods. Patient M., male, 64, was hospitalized at the National Medical Research Center for Therapy and Preventive Medicine in February 2020 with a diagnosis of CHD. Stable angina, FC III, multivessel coronary lesions. The recanalization of chronic occlusion of the right coronary artery was performed at the first stage. During the next stage of revascularization of the left main coronary artery, an acute occlusion of the circumflex artery occurred. Despite the acute occlusion, no ischemic dynamics wasm reported on the electrocardiogram, there were no complaints, hemodynamics was stable. Ischemic events did not occur due to the formed network of collaterals out of the system of the right coronary artery. This allowed the complication to be corrected without consequences for the patient. Results and discussion. Thanks to the accumulated experience and advanced technologies, the success rate of recanalization has reached 90–95 %, and complications are not more common than in cases of stenting of non-occlusive lesions. The conducted studies have proved that successful recanalization of CCO improves the patient’s clinical and functional status, intracardiac hemodynamics and quality of life.Conclusion. The clinical case given above clearly demonstrates the need for endovascular revascularization of CCO. The formed collateral network ensured blood flow in the area of acute occlusion and prevented the development of ischemia and myocardial infarction.