Pulmonary artery denervation to treat pulmonary arterial hypertension: the single-center, prospective, first-in-man PADN-1 study (first-in-man pulmonary artery denervation for treatment of pulmonary artery hypertension).

Objectives: This study was designed to test the safety and efficacy of pulmonary artery (PA) denervation (PADN) for patients with idiopathic PA hypertension (IPAH) not responding optimally to medical therapy.

Background: Baroreceptors and sympathetic nerve fibers are localized in or near the bifurcation area of the main PA. We previously demonstrated that PADN completely abolished the experimentally elevated PA pressure responses to occlusion of the left interlobar PA.

Methods: Of a total of 21 patients with IPAH, 13 patients received the PADN procedure, and the other 8 patients who refused the PADN procedure were assigned to the control group. PADN was performed at the bifurcation of the main PA, and at the ostial right and left PA. Serial echocardiography, right heart catheterization, and a 6-min walk test (6MWT) were performed. The primary endpoints were the change of PA pressure (PAP), tricuspid excursion (Tei) index, and 6MWT at 3 months follow-up.

Results: Compared with the control group, at 3 months follow-up, the patients who underwent the PADN procedure showed significant reduction of mean PAP (from 55 ± 5 mm Hg to 36 ± 5 mm Hg, p < 0.01), and significant improvement of the 6MWT (from 324 ± 21 m to 491 ± 38 m, p < 0.006) and of the Tei index (from 0.7 ± 0.04 to 0.50 ± 0.04, p < 0.001).

Conclusions: We report for the first time the effect of PADN on functional capacity and hemodynamics in patients with IPAH not responding optimally to medical therapy. Further randomized study is required to confirm the efficacy of PADN. (First-in-Man Pulmonary Artery Denervation for Treatment of Pulmonary Artery Hypertension [PADN-1] study; chiCTR-ONC-12002085).