Bunel V, et al. - Researchers performed a histological analysis of the explanted lungs, to report the underlying histological lesions in chronic obstructive pulmonary disease (COPD) patients with severe pulmonary hypertension (PH). Three groups of COPD patients that were retrospectively compared were: severe PH-COPD (n=10), moderate PH-COPD (mPAP [mean pulmonary pressure] between 25 and 34 mm Hg without low cardiac index) (n = 10), no PH (mPAP <25mm Hg) (n = 10). The wall of medium-size arteries, the remodelling of microvessels and the pulmonary capillary density were assessed. The severe PH-COPD group vs the moderate PH group demonstrated significantly higher remodelling score of the microvessels and lower capillary density. A specific histological pattern was noted in patients with severe PH-COPD, this pattern was found to be different from that observed in COPD patients with moderate PH or without PH.