Histometrical Studies of Pulmonary Hypertension with Special Reference to Uremic Pneumonitis

抄録

1) By means of histometrical treatments pulmonary arteries of autopsy cases were reduced to the state in which internal elastic membrane was perfectly extended. The distance from the center of exactly circular arterial lumen to the middle point of the muscular coat was defined as anatomical radius R and the thickness of the media as D. In the region from R=100μ to R=1000μ, the relation of R and D could be expressed by a general formula D=aR^b, where a and b were constants.
2) Regression equations of pulmonary arteries of autopsy cases which were regarded to have had normal pulmonary circulation were determined in the above-mentioned region, and the values of estimated D at R=100μ was calculated from the regression equations of individual cases. Upper rejection limit of estimated D of normal pulmonary arteries was determined. When the estimated D of a certain autopsy case exceeded the upper rejection limit, the case was regarded to have hypertrophied muscular coat and pulmonary hypertension. The method was found effective in screening relatively pronounced pulmonary hypertension.
3) The presence of moderate medial hypertrophy as a result of relatively mild pulmonary hypertension could be estimated by comparison of the regression equation of the group to that of normal pulmonary arteries.
4) Medial hypertrophy of pulmonary artery was confirmed in cases with prolonged arterial hypertension in systemic circulation and was found to be more prominent in the group with uremie pneumonitis than in the group without the lesion in spite of uremia.
5) The pathogenesis of uremic pneumonitis was discussed in reference to pulmonary hypertension. The presence of pulmonary hypertension was regarded to be one of the important pathogenic factors in precipitating pulmonary lesions of the type of “uremic pneumonitis”.