4282Pulmonary artery denervation in patients with residual pulmonary hypertension after pulmonary endarterectomy: one-year results of the first -in-man, sham-controlled, pilot randomized clinical trial
Authors: Romanov A , Cherniavskiy A , Novikova N , Edemskiy A , Ponomarev D , Shabanov V , Losik D , Kretov E , Stenin I , Elesin D , Pokushalov E , Steinberg J S 
Published: October 2019

Abstract

Background
Pulmonary endarterectomy (PE) is the method of choice in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Despite the positive effect after surgery combined with medical treatment, 10–40% of patients develop residual CTEPH. Pulmonary artery denervation (PAD) is a novel treatment in PAH with optimistic results but was not tested in patients with residual CTEPH.

Objective
To assess the safety and efficacy of PAD using remote magnetic navigation system in patients with residual CTEPH after PE.

Methods
278 patients with CTEPH after PE were screened. 50 patients (mean age 47.6±14.3, 50% female) with a history of residual CTEPH (a resting pulmonary artery pressure ≥25 mm Hg or pulmonary vascular resistance >400 dyn sec cm–5 despite medical therapy 6 months after PE) were randomized into two groups: PAD (n=25; PAD group) or medical therapy with riociguat (n=25; MED group). In both groups right heart catheterization (RHC)was performed after randomization. In the PAD group, remote magnetic navigation systemwas used to target sympathetic nerve fibers, located near bifurcation and ostia of the main brunches of right and left pulmonary arteries. This study was conducted as double-blind and sham-controlled and the primary endpoint was change in pulmonary vascular resistance (PVR) by RHC at 12 months. Secondary endpoints included 6-minute walk test (6MWT), pulmonary artery pressure, and clinical outcomes. All patients were followed for 12 months after randomization. Unpaired t-test and Fisher's exact test were used for between-group comparisons of continuous and categorical variables, respectively. A p value of less than 0.05 was considered statistically significant.

Results
Two patients (one in each group) developed groin hematoma which resolved without any consequences. At the end of 12 month, the PVR was significantly low in PAD group as compared with MED group (343±149 dyn sec cm–5 vs 444±145 dyn sec cm–5, respectively; mean difference −101, 95% confidence interval: −193 to −10; p=0.032). The mean, systolic and diastolic PA pressure was also reduced significantly in PAD group compared to MED group (25.8±7.3mm Hg vs 33.8±6.4 mm Hg, 46.2±14.1mm Hg vs 54.2±8.1 mm Hg,13.2±5.3mm Hg vs 20.2±4.8mm Hg; p<0.001, p=0.002, p<0.001, respectively). The PAD group demonstrated significant improvement of the 6MWT over MED group (470±84 m vs 399±116 m, respectively, p=0.031). In the PADN group 1 (4%) patient was hospitalized due to heart failure progression compared to 7 (29%) patients in MED group (p=0.049). One patient in PAD group and two patients in MED group died.

Conclusions
Pulmonary artery denervation in patients with residual pulmonary hypertension was safe and effective, and resulted in substantial reduction of pulmonaryvascular resistance and pulmonary artery pressure during 12 months follow up, accompanied by improved 6-minute walk test and reduced need for hospitalization. Clinical Trials Registration: NCT02745106

Acknowledgement/Funding
Grant from Biosense Webster