Refined balloon pulmonary angioplasty driven by combined assessment of intra-arterial anatomy and physiology--Multimodal approach to treated lesions in patients with non-operable distal chronic thromboembolic pulmonary hypertension--Technique, safety and efficacy of 50 consecutive angioplasties.

BACKGROUND/OBJECTIVES: Balloon pulmonary angioplasty (BPA) is an emerging therapeutic method in CTEPH. We aimed to prove the safety and efficacy of refined BPA driven by combined assessment of intra-arterial anatomy (IVUS/OCT) and physiology (pulmonary pressure ratio, PPR) in non-operable distal CTEPH.

METHODS: 11 pts (mean age 76, 59–84, 7 males) were enrolled in the BPA program according to the following inclusion criteria: 1. Non-operable CTEPH; 2. RHC with mPAP > 30 mm Hg; 3. At least one segmental perfusion defect at lung scintigraphy; 4. WHO class > II. Overall, 9 pts underwent 27 BPA sessions (mean 3 sessions per patient, range 1–5), 50 pulmonary arteries were dilated (mean 6 vessels per patient, range 3–9; 2.03 dilated arteries per session). All the angioplasties were performed according to an algorithm, which incorporated anatomical and functional assessment of targeted lesions.

RESULTS: We performed BPA of 32 web lesions, 5 ring-like stenosis and 13 complete obstructions. BPA resulted in clinical and hemodynamic improvement. WHO class improved from pre-BPA to post-BPA (p = 0.018), and 6 MWD increased from 304 m to 384 m (p = 0.03), NT-proBNP dropped from 1248 pg/ml to 730 pg/ml (p < 0.001). Mean PAP and PVR decreased (p = 0.01), while CO and CI increased (p = 0.01). All dilated arteries were patent at angiographic reassessment. No significant complications occurred and all treated patients are still alive. Insignificant transient reperfusion pulmonary oedema occurred in only 2 patients, who responded well to supplemental oxygen.

CONCLUSIONS: Refined BPA with assessment of intrapulmonary physiology using a pressure wire and precise evaluation of anatomy with IVUS and OCT provides hemodynamic and functional improvement, with minimal complications in distal non-operable CTEPH. This observation requires further validation in a large prospective study.