Purpose of the study: to analyze the etiology, diagnostic criteria and results of treatment of life-threatening conditions in pericarditis of different etiologies (based on our clinic materials).Materials and methods. The study included cases of hospitalization of patients with a diagnosis of «Pericarditis» and ICD-10 codes for pericardial diseases for the period from 2009 to 2018. In the course of the work, the history and clinical picture of the disease, laboratory and radiation research methods were analyzed. All patients started treatment of the underlying disease and performed symptomatic therapy, including those aimed at restoring hemodynamics and normalizing water and electrolyte disorders, stopping inflammation and auto-aggression of the immune system. When signs of compression/cardiac tamponade were detected, pericardiocentesis was performed, according to indications, drainage/fenestration of the cardiac sac, pericardiotomy were performed. In the postoperative period was carried out antibacterial and symptomatic therapy.Results. Life-threatening diseases of the pericardium accounted for 32,03% of all patients treated in the hospital for pericarditis. The most frequently detected signs of a hemodynamically significant compression and cardiac tamponade, less often purulent and constrictive P. Isolated 25 patients underwent closed drainage with pericardiocentesis, in 1 case the drainage was supplemented with f ibrinolytic therapy. Sanitation of the cavity and fenestration of the pericardium were carried out in 11 patients, pericardiotomy with notched drainage in 2 patients, thoracotomy with pericardiectomy – 4. In the postoperative period, the symptoms of inflammation were reduced, the level of cardiac enzymes decreased, the electrolyte balance stabilized. Most patients noted a distinct regression of the symptoms of pericarditis and cardiac compression. Recurrent P was noted in 5 cases, deaths occurred in 4 cases (8,16%).Conclusion. Early verification of the diagnosis and timely decompression of the heart with fractional evacuation of the exudate or pericardectomy with respect to the sequence of release of the heart chambers from adhesions and adhesions against the background of complex therapy allows to achieve positive dynamics, and fenestration of the cardiac bag with the formation of a sufficiently sized opening during recurrent fluid accumulation or intrapericardial fibrin. development of severe complications of pericarditis even in patients with multiple concomitant diseases evanii and oncopathology.