Vascular Injury Is a Major Cause of Lung Injury After Balloon Pulmonary Angioplasty in Patients With Chronic Thromboembolic Pulmonary Hypertension

BACKGROUND: Balloon pulmonary angioplasty (BPA) has become an alternative treatment for inoperable patients with chronic thromboembolic pulmonary hypertension. Lung injury (LI) is a major complication of BPA and may attenuate the benefits of BPA. Therefore, we conducted a retrospective study to evaluate the association between patient and procedural characteristics and LI in patients with chronic thromboembolic pulmonary hypertension. METHODS AND RESULTS: We reviewed 76 patients with chronic thromboembolic pulmonary hypertension who underwent BPA and multidetector computed tomography scanning pre-and post-BPA procedures. We performed BPA on 1247 vessels during 297 BPA procedures and reviewed 594 multidetector computed tomography scans. By comparing pre-and post-BPA multidetector computed tomography images, we diagnosed LI as follows: newly appeared ground-glass opacity, consolidation, and pleural effusion. LI was detected using multidetector computed tomography scans during 138 procedures (47%), and mechanical ventilation was required during 40 procedures (13%). Angiographic findings of extravasation with or without simultaneous clinical symptoms (BPA-related vascular injury) occurred during 50 procedures (17%). In mixed-effect logistic regression models, the BPArelated vascular injury was an independent predictor of LI after BPA, odds ratio, 20.1 (6.43-63.1). High mean pulmonary artery pressure before BPA procedure and BPA-related vascular injury were independent predictors of mechanical ventilation after BPA, odds ratio, 1.13 (1.03-1.24) and 10.8 (3.77-30.9), respectively. CONCLUSIONS: Vascular injury during BPA could be a triggering factor of LI after BPA, and its severity could be exacerbated by a high pulmonary artery pressure.