Plexiform and intima lesions in IPAH. Two cellular plexiform lesion are seen in a branching point of a muscular pulmonary artery (a, highlighted by arrows). Another pulmonary artery shows overall intima thickening with predominance of extracellular matrix (b). However, the cells have a more concentric arrangement at the branching point (arrows), reminiscent of the process seen in panel (a). Indeed, a close up of a lesion in the same pulmonary artery shows increased numbers of endothelial cells immersed in an extracellular rich background (c, highlighted in yellow circle).
Additional keywords: plexiform lesion,media,medial hypertrophy,occlusive