Hypertrophic cardiomyopathy (HCM) is an underdiagnosed genetic heart disease with a prevalence of 0.2–0.5  %. Although the prognosis of HCM is relatively favorable, the annual overall mortality is about 0.7 %. The most common complication of HCM is obstruction of the left ventricular outflow tract (LVOT). Careful diagnosis and timely identification of high-risk patients by confirming the presence and degree of obstruction of the left ventricular outflow tract may reduce morbidity and mortality due to timely and correctly selected treatment. One-third of patients with HCM have echocardiographically confirmed LVOT obstruction at rest, and another third may have LVOT obstruction with provocation. Our clinical case demonstrates the presence of a small group of patients with HCM, whose LVOT obstruction is underestimated by transthoracic echocardiography (TTE) neither at rest nor when using provocative tests (Valsalva tests, exercise), and its hemodynamic significance is revealed only with invasive hemodynamic catheterization of the heart. Below, we illustrate the utility of hemodynamic catheterization as an adjunctive tool to echocardiography to help establish the presence, magnitude, and location of obstruction in patients with HCM in the absence of such data on TTE. In case of a high degree of suspicion that LVOT obstruction is responsible for refractory symptoms, catheterization can establish the presence of a hemodynamically significant LVOT gradient and, accordingly, without deviating from clinical recommendations, to carry out optimal surgical treatment, in our case – septal alcohol ablation with subsequent elimination of symptoms and restoration of the patient’s endurance to physical exertion.

2022 is a special year for the development of world cardiology: two important events are celebrated, namely the 40th anniversary of the first percutaneous angioplasty performed by Andreas Gruentzig (Switzerland) in September 1977 and the 20th anniversary of the first successful transcatheter aortic valve implantation (TAVI) in humans. Undoubtedly, these two techniques changed the development of the cardiovascular field of medicine for many decades. The spread of aortic stenosis, as the most common acquired heart disease, allows us to understand the importance of the latest methods of its correction. The growing prevalence of use and changes in indications for this operation require the collaboration of specialists in various specialties: cardiologists, cardiac surgeons, anesthesiologists, resuscitators, perfusiologists, rheumatologists, electrophysiologists and others. To implement the method in medical institutions, separate teams of doctors «Heart Team» are created that not only participate in the selection of patients, but also participate in the implementation of TAVI. Gaining experience, creating an optimal design and reducing the diameter of the delivery catheters has led to a reduction in the incidence of complications and the possibility of use in lower risk groups.