Distal pulmonary arterial remodeling in end-stage cystic fibrosis

Cardiovascular complications are increasingly important in the ageing cystic fibrosis (CF) population, where pulmonary vasculature might be affected by endothelial CFTR-dysfunction and distal airway (DA) inflammation, hypoxemia and remodeling. Yet, the extent and relationship between distal pulmonary artery (PA) and DA remodeling, has not been characterized. Lung cores (±2.8cm³) from human explanted, inflated end-stage CF (n=5, 2 cores/lung) and control lungs (n=5, 2cores/lung), were scanned with micro-CT. The number of DA and PA segments were quantified on 3D-segmentations. In CF, PA diameter was measured in PA pairs where one branch accompanied an obstructed (oPA) and the other accompanied a non-obstructed airway (noPA). In controls, PA diameter was measured in every visible PA pair. The number of PA segments decreased from 18.5/mL [14.5-40.7] in control to 11/mL [5.3-16.7] (p=0.01) in CF. In controls, the ratio of PA diameters within a PA pair was 0.71 [0.60-0.83] (n=22 pairs), while in CF the ratio of oPA to noPA diameter (n=7 pairs) was only 0.58 [0.50-0.64] (p=0.02). In end-stage CF, the pulmonary vasculature is characterized by a decrease in number of PA and focal PA changes associated with DA obstruction. This underlines the importance of pulmonary vascular disease in end-stage CF, which might lead to pulmonary hypertension, associated with a worse prognosis in CF patients. <fig><object-id>erj;64/suppl_68/OA2908/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>