Poor Subpleural Perfusion Predicts Failure After Balloon Pulmonary Angioplasty for Nonoperable Chronic Thromboembolic Pulmonary Hypertension

PSP in the capillary phase, suggesting the presence of small vessel disease with diffuse distal thrombosis, is a predictor of BPA failure. PSP was also associated with less developed bronchial arteries, which suggests a key role of bronchial-pulmonary anastomoses in maintaining the pulmonary capillary bed open downstream of the pulmonary arterial obstruction. PSP affected approximately 15% of patients with nonoperable CTEPH who underwent BPA.