Pulmonary Artery Denervation for Treatment of Pulmonary Arterial Hypertension: Results From a Controlled Before and After Study

Background: Pulmonary arterial hypertension (PAH) is a severe disease. 6-minute walk distance (6MWD) is correlated with the prognosis of PAH patients. We previously reported the safety and efficacy of pulmonary artery denervation (PADN) for patients with idiopathic PAH (IPAH) who were unresponsive to target drugs. However, PADN has not been tested in a well-designed study for patients with IPAH/PAH or pulmonary hypertension (PH). Objectives: The present study aimed to analyze the difference in 6-minute walk distance (6MWD) at 6-month after PADN and standard pharmacotherapy. Methods: Between February 2013 and June 2014, a total of 28 patients with IPAH (n=11), PH from left heart disease (n=8), and 9 secondary PAH were included in this study. A wash-out consisting of 5 half-lives for target drugs was performed for all the patients. Next, medications were prescribed for a 6-month duration for the patients (Medication treatment). A second wash-out (5 half-lives) was completed for all the patients after the 6-month medication treatment. Finally, PADN was performed for these patients (PADN treatment), and an additional 6-month follow-up period was completed. The primary endpoint was the difference in the ∆6MWD (defined as value at 6-month minus baseline) between two treatments. Results: After 6-month treatment, there was significant difference in the ∆6MWD between PADN (65±85 m) and Medication (13±24 m) treatment (95% CI -21.34-3.49, p=0.002), coupling with the differences in the reduction of systolic pulmonary artery pressure (PAP, -13.75±14.1 mmHg vs. -0.46±3.47 mmHg, p<0.001), mean PAP (-7.86±6.10 mmHg vs. -0.14±2.48 mmHg, p<0.001), mean right atrial pressure (-2.53±3.75 mmHg vs. -0.21±2.62 mmHg, p=0.007), and pulmonary vessel resistance (-4.59±7.06 Woods unit vs. -0.17±2.56 Woods unit, p=0.001). PADN treatment was associated with less frequent 6-month PAH-related event (10.8%), compared to 42.9% in Medication treatment (p=0.005). Conclusion: The present study showed that PADN treatment was associated with significant improvement of 6MWD and less PAH-related event. Further study was required to show the benefit of PADN in reducing mortality in patients with IPAH and secondary PAH.