[Primary hypertension of the lesser circulation]

The article presents a survey of the literature data and findings of the author's own investigations concerning various aspects of primary pulmonary hypertension (PPH). PPH -- is a polyentiological suffering. As a nosological form it was described in the fifities. There are two forms of PPH: congenital and acquired. In its turn, the congenital form comprises two variants of anomalies of the pulmonary vessels: the retnetion of the fetal structure of the pulmonary arteries and an anomaly at the level of intraorgan vascular anastomoses. Constant morphological characteristics of the two forms of PPH are as follows: endosclerosis of major branches of the pulmonary artery and focal sclerosis of their tunica media; a considerable degree of hypertrophy of the right ventricle usually not observed in other diseases. The acquired PPH may develop as a result of exposure to drugs, in thromboembolism, under high mountain conditions, etc. A question arises, whether it is justifiable to call as "primary" the acquired forms of pulmonary hypertension, since in the majority of cases their secondary nature is evident. Thus, the term "primary pullomonary hypertension" should be applied only to congenital forms of the disease. Possible in order to single out this group of desorders it would be reasonable to devise a more suitable name, for instance, "isolated pulmonary hypertension" which will render a broader sense to this polyetiological suffering.