THE PHYSIOLOGICAL MECHANISMS OF THE PULMONARY VENOUS HYPERTENSION

Abstract

In the review regulatory mechanisms of functions of pulmonary venous vessels have been considered as well as the signifi cance of their impairment in the development of the pulmonary hypertension, caused by the left ventricular cardiac failure. One of the trigger mechanisms of the development of the pulmonary hypertension as a result of the elevation of the left atrial and pulmonary venous pressure is the reflectory constriction of the pulmonary arterioles (Kitayev’s reflex). Further, the development of endothelial dysfunction and pulmonary vessels remodeling with the phenomenon of “arterializations” of the pulmonary veins take place. The exact evaluation of the pulmonary vascular resistance value in the clinical practice is a difficult task. This parameter, being integrated, does not allow to evaluate the resistance values of pulmonary arterial and venous vessels in the conditions of pulmonary hypertension and to give exact characteristics of their changes, as a result. The mechanisms of development of the pulmonary venous hypertension could not be explicated using the simplified model of the pulmonary vasoconstriction, because the main features of the pulmonary circulation are the presence of arteriovenous and bronchopulmonary shunts, and pulsatile character of the blood flow. To understand the exact pathogenesis of this pathology the further fundamental investigation not only on the cell level, but also on organ and system levels are needed.