All are the histological features of Pulmonary hypeension -

Ans. is 'c' i.e., Thrombi in pulmonary vasculature Pulmonary Hypeension o In pulmonary hypeension pathological changes are seen from main pulmonary aeries to aerioles. They are : (a) Aerioles and small pulmonary aeries : (i) Medial hyperophy (ii) Thickening and reduplication of elastic lamina. (iii) Plexiform pulmonary aeriopathy in which intraluminal tuft of capillary formation occurs in dilated thin walled aeriolar branches. (b) Medium sized Pulmonary aeries : (i) Medial hyperophy; which is not marked in secondary pulmonary hypeension. (ii) Concentric intimal thickening (iii) Adventitial fibrosis (iv) Thickening and reduplication of elastic laminae. (c) Large Pulmonary aeries : o Atheromatous deposits o Vasoocclusive disease itself may lead to pulmonary hypeension.