In many patients, mainly in the age group of 60–75 years, with coronary heart disease, valvular diseases, cardiac conduction disorders and other accompanying age-associated pathology are detected. This article presents a clinical case of a patient who was hospitalized with a primary diagnosis of myocardial infarction complicated by complete atrioventricular block. During the examination, a bicuspid aortic valve with stenosis of the second degree, subocclusion of the right coronary artery (95 %) were additionally revealed. The patient underwent emergency stenting of the right coronary artery and was implanted a temporary pacemaker. Due to persisted block after 10 days permanent pacemaker was implanted, but during further observation and examination, ultrasound and tomographic signs of infective endocarditis of the aortic valve were detected with an increase in the degree of its stenosis up to the third degree, abscess of the aortic root and interventricular septum and formation of left ventricular to right atrial shunt (Gerbode defect). The patient underwent aortic valve replacement, Gerbode defect repair with xenopericardial flaps, and pacemaker replacement with epicardial electrode implantation with good clinical results. Step-by-step diagnostic, therapeutic and surgical tactics are given.