Severe pulmonary hypertension associated with chronic obstructive pulmonary disease: A prospective French multicenter cohort

BACKGROUND: A small proportion of patients with chronic obstructive pulmonary disease (COPD) patients present severe pulmonary hypertension (PH), defined by mean pulmonary artery pressure (mPAP) >= 35 mm Hg measured by right heart catheterization. Little is known about the characteristics of severe PH-COPD. The aim of the study based on a national registry was to describe this phenotype.METHODS: We prospectively included and followed patients with incident PH-COPD. Clinical, functional, hemodynamic data at inclusion and follow-up were retrieved. Survival assessed by Kaplan Meier analysis was the primary end-point.RESULTS: From 2012 to 2016, 99 patients from 13 French centers were included in the study (82 males; median age 66.0 years [interquartile range 62.0-72.0]). At inclusion, most patients had marked dyspnea(55.6% and 22.2% New York Heart Association class III and IV, respectively). During 12 months before inclusion, 42.9% had an exacerbation requiring a hospitalization. Pulmonary function tests showed a moderate obstructive pattern with median (interquartile range) FEV1 50.0 [35.0-63.0] % predicted and low diffusing capacity for carbon monoxide, median 20.0 [16.5-30.6] % predicted. The median values for PaO2 and PaCO2 on room air were 50.0 [44.8-62.0] and 36.0 [31.1-43.0] mm Hg. Median values of mPAP, pulmonary artery occlusion pressure, cardiac index and pulmonary vascular resistance were 42.0 [37.0-48.0] mm Hg, 11.0 [9.0-14.0] mm Hg, 3.0 [2.4-3.6] L/min/m(2), and 6.3 [4.27.9] WU, respectively. Mean restricted survival was 15.0 [13.9-16.0] months.CONCLUSIONS: Severe PH-COPD is characterized by moderate airway obstruction but marked dyspnea and marked hypoxemia, low DLCO and high mPAP. This phenotype is associated with poor prognosis. (C) 2021 The Author(s). Published by Elsevier Inc. on behalf of International Society for Heart and Lung Transplantation.