Preliminary study on the short-term changes of pulmonary perfusion after a single balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension.

Background: Little is known about immediate responses of blood perfusion to the balloon pulmonary angioplasty (BPA) procedure.

Objectives: To investigate the changes in pulmonary perfusion of balloon-dilated vessels and untreated vessels with before, immediately after a single BPA and at follow-up.

Design: Retrospective single-center cohort study.

Methods: Patients who had chronic thromboembolic pulmonary hypertension (CTEPH) and completed the pulmonary perfusion single photon emission computed tomography (SPECT) imaging before, immediately after BPA and at follow-up were included. We evaluated the perfusion defects of both-lung, BPA target (balloon dilated) and non-target (untreated) vessel segments according to Begic 3-point scale in each lung segment.

Results: Forty patients (40 BPA procedures) were included and were given next BPA after 89 (62-125) days. The hemodynamic parameters including mPAP, PVR, and RAP were significantly improved after a single BPA. Visual scoring results of pulmonary perfusion imaging in 40 BPAs showed the perfusion defect scores of target vessels reduced from 5.6 ± 2.6 to 4.2 ± 2.2 (p < 0.001) immediately after BPA, and then further diminished to 3.1 ± 1.9 (p < 0.001) at follow-up. While in the non-target vessels, the post-BPA perfusion defect scores did not change significantly (13.4 ± 4.7 versus 12.8 ± 4.6, p = 0.182), but tended to decrease at follow-up (12.2 ± 4.2). However, there were 17 BPAs of which the post-BPA perfusion defect scores of non-target vessels increased significantly (p < 0.001), but decreased at follow-up.

Conclusion: In addition to improving the blood perfusion of target vessels, BPA also has a certain effect on the perfusion of some non-target vessels.