[State of the cardiovascular system in patients with decompensated mitral valve defect under conditions of high altitude].

A clinical study was conducted in 236 patients with decompensated mitral valve disease--permanent residents of the areas located at various altitudes in the Pamirs and Tien Shan (760 to 4,200 m above the sea level). The main parameters of haemodynamics were studied by means of the dye dilution method in 158 of them, as well as the indices of cardiodynamics by way of polycardiography. The data obtained in 120 normal individuals living in foothills (760 m) served as control. It was demonstrated that with the same stages of cardiac insufficiency, the most striking changes in the haemo- and cardiodynamics were noted among the residents of the high altitude areas. Among those living at medium altitudes (1,650 to 2,020 m), the cardiac output and the left ventricular function appeared to be reduced most distinctly. These patients also exhibited a clear relationship between the main variables of the cardiovascular functions and the severity of cardiac insufficiency. The revealed clinical and functional peculiarities of the decompensated mitral valve disease in mountaneers are atrributable to the effect of hypoxic hyposy upon the regulation of the respiration and the pulmonary circulation.