[Hemodynamics of pulmonary circulation in hypertension based on data from radionuclide studies].

The authors presented the results of a combined radionuclide study of the state of pulmonary hemodynamics in patients with essential hypertension. Altogether 132 patients were investigated. Radiocardiography, perfusion scintigraphy and a study of the regional pulmonary blood flow using radioactive Xe were conducted. An analysis of the results has shown that in some patients pulmonary hypertension develops even at early stages of the disease and is particularly marked in stages IIB-III. The mechanism of development of pulmonary hypertension depended at each stage on the interrelationship and time course of indices that characterized pulmonary circulation, and was of different nature. Hemodynamic disorder was manifested in blood mass redistribution from the lower lung regions to the upper ones, slowing down of rate parameters and a raise of pulmonary vascular resistance.