The protective effects of radiofrequency pulmonary artery denervation on the progression of chronic thromboembolic pulmonary hypertension

Abstract This study aimed to assess the safety and efficacy of radiofrequency pulmonary artery denervation with the Simplicity system in patients with distal chronic thromboembolic pulmonary hypertension. Methods and results 60 chronic thromboembolic pulmonary hypertension patients with mean pulmonary artery pressure >25 mm Hg and absence of proximal artery lesion defined by pulmonary angiography were randomized into 2 groups. Group 1 included 30 patients who underwent pulmonary artery denervation procedure. The other 30 patients were assigned to the control group (only angio plus right heart catheterization). The procedure of pulmonary artery denervation was performed at the lateral wall of main pulmonary artery and ostium of the left and right pulmonary arteries using the electrode from Simplicity denervation system. The programmed ablation parameters were temperature >50°C and time = 120 s. Using the coronary guiding technique, the tip of electrode was applied at each spot rotating the tip with pace of 2 mm. The success was defined by decrease of mean pulmonary artery pressure >10%, absence of complications. The primary end point was comparison of mean pulmonary artery pressure change from baseline to 12 months in pulmonary artery denervation group compared with change from baseline to 12 months in control group. The secondary point was change in 6-min walk distance and pulmonary vascular resistance at the 12-month follow-up. There were no complications after pulmonary artery denervation. The hemodynamic success was achieved in 93% of all cases. The mean number of radiofrequency applications to achieve success was 10.3 per patient. During follow-up period 3 patients died in pulmonary artery denervation group: (1 died of gastro-intestinal bleeding, 2 – of right ventricular failure) and 3 patients in control group. The mean decreases in the mean pulmonary artery pressure were 8.7 mm Hg in the pulmonary artery denervation group and 3.1 mm Hg in control group (p