Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: Evaluation of haemodynamic effects, complication rates and radiation exposure over time.

Background: In patients undergoing balloon pulmonary angioplasty (BPA) for inoperable chronic thromboembolic pulmonary hypertension (CTEPH), single-centre series from expert centres have recognized a learning curve for the magnitude of haemodynamic benefits.

Objective: To report our 7-year experience with BPA, focusing on haemodynamic effects, complication rates and radiation exposure over time.

Methods: Patients with CTEPH who were treated with BPA between May 2013 and February 2020 were analysed during the 'initial period' versus the 'recent period' (split date: March 2017).

Results: Among 192 patients who underwent at least one BPA procedure, 156 were included in the safety/radiation analysis and 119 were included in the efficacy analysis. During the 'recent period' versus the 'initial period', the median [interquartile range] number of procedures per patient was higher (4.5 [4.0-6.0] vs. 4.0 [3.0-4.0]; P=0.03), as was the number of dilated vessels per procedure (4.0 [3.5-5.0] vs. 3.5 [3.0-4.0]; P=0.002). Changes in haemodynamic parameters were also greater (mean pulmonary artery pressure: -22% [-31% to -14%] vs. -37% [-44% to -29%]; P=0.001; pulmonary vascular resistance: -38% [-51% to -8%] vs. -53% [-69% to -33%]; P=0.002); complication rates were similar (5.7% vs. 9.3% of procedures; P=0.38); and radiation exposure was lower (effective dose per patient: 43.9 [31.6-66.5] vs. 67.8 [47.9-101.9] mSv; P<0.001).

Conclusion: Our analysis is consistent with a learning curve for the magnitude of haemodynamic improvements. The complication rate was low and did not change over time, but radiation exposure decreased.