PADN-5: Pulmonary artery denervation shows promise

SAN DIEGO — Pulmonary artery denervation showed improved outcomes in patients with combined pre- and postcapillary pulmonary hypertension, according to the randomized, sham-controlled PADN-5 trial.

Unfortunately, medications targeting pulmonary artery hypertension are not recommended for patients with combined pre- and postcapillary pulmonary hypertension. However, pulmonary artery denervation has never been studied for this patient population in a randomized trial, Shao-Liang Chen, MD, from Nanjing First Hospital in China, said during his presentation of the data at TCT 2018.

The PADN-5 study included 112 patients with recently worsening HF who had been stabilized for at least 3 days. Of these patients, 98 were randomly assigned pulmonary artery denervation (n = 48) or sham procedure and sildenafil (n = 50). All patients received standard medical therapy for HF.

At 6-month follow-up, 6-minute walk distance — the primary endpoint — increased by 21.4% in patients treated with peripheral artery denervation compared with 4.9% in those treated with sildenafil (80 m vs. 17.5 m; P < .001).

Notably, Chen said, fewer patients in the pulmonary artery denervation group vs. the sildenafil group experienced a more than 15% reduction in 6-minute walk distance (6.3% vs. 14%; HR = 2.947; 95% CI, 1.152-4.501). The researchers also identified clinical worsening as a predictor for a decrease of 1 standard deviation in 6-minute walk distance (HR = 3.023; 95% CI, 1.052-8.742).

After 6 months, pulmonary vascular resistance measured during right heart catheterization — a secondary endpoint — decreased by 29.8% in the peripheral artery denervation group compared with only 3.4% in the sildenafil group (HR = 4.73; 95% CI, 2.05-10.89). Another important finding, according to Chen, was the lack of change in right arterial pressure at 6-month follow-up in both groups.

Clinical worsening — another secondary endpoint — was also significantly more common in patients receiving sildenafil and sham procedure vs. peripheral artery denervation (40% vs. 16.7%; P = .014), Chen noted.

There were five deaths in the sildenafil group and only two in the peripheral artery denervation group, although there was not a significant difference in terms of all-cause death between the two groups, according to Chen.

At baseline, nearly 40% of patients in both groups had HF with preserved ejection fraction. The inclusion of both patients with preserved EF and those with reduced EF was a potential limitation of the study, Chen said. Additionally, he noted the use of sildenafil in the sham control group and use of the 6-minute walk distance as an endpoint also may have limited the study.

“The PADN-5 study demonstrated the benefits of peripheral artery denervation for patients with combined pre- and postcapillary pulmonary hypertension,” Chen said, noting that patients with HFpEF and HFrEF benefited equally from the treatment. “There also wasn’t any sign showing the harm of sildenafil to patients with combined pre- and postcapillary pulmonary hypertension.” – by Melissa Foster

References:

Chen S-L, et al. Late-Breaking Clinical Science 1, Co-Sponsored by The Journal of the American College of Cardiology. Presented at: TCT Scientific Symposium; Sept. 21-25, 2018; San Diego.

Zhang H, et al. J Am Coll Cardiol. 2018;doi:10.1016/j.jcin.2018.09.021.

Disclosure: Chen reports no relevant financial disclosures.