Balloon pulmonary angioplasty (BPA) in chronic thromboembolic pulmonary hypertension (CTEPH) improves hemodynamics and exercise capacity. However, its effect on respiratory function is unclear.
To investigate the effect of BPA on respiratory function.
We enrolled inoperable CTEPH who underwent BPA primarily in lower lobe arteries (first series) and upper and middle lobe arteries (second series). We compared changes in hemodynamics and respiratory function between different BPA fields.
Measurements and Main Results
Sixty-two BPA sessions were performed in 13 consecutive patients. Mean pulmonary artery pressure and pulmonary vasculature resistance significantly improved from 44 ± 8 to 23 ± 5 mmHg and 818 ± 383 to 311 ± 117 dyne/s/cm−5. The percentage of predicted carbon monoxide lung diffusion capacity (%DLco) decreased after BPA in the lower-lung field (from 60 ± 8% to 54 ± 8%) with no recovery. %DLco increased after BPA in the upper-middle lung field (from 53 ± 6% to 58 ± 6%) and continued to improve during the follow-up (from 58 ± 6% to 64 ± 11%). The VE/VCO2 slope significantly improved after BPA in the lower-lung field (from 51 ± 13 to 41 ± 8) and continued to improve during the follow-up (from 41 ± 8 to 35 ± 7); however, the VE/VCO2 slope remained unchanged after BPA in the upper-middle lung field. Changes in %DLco and the VE/VCO2 slope significantly differed between lower and upper-middle lung fields.
The effect of BPA on respiratory function in patients with CTEPH differed depending on the lung field.