There is scarce evidence for pulmonary artery denervation (PADN) as a potential treatment for chronic postcapillary pulmonary hypertension (PH). We aimed to perform a proof-of-concept of PADN in a translational model of chronic PH. Nineteen pigs with chronic postcapillary PH (secondary to pulmonary vein banding) were randomized to surgical-PADN (using bipolar radiofrequency clamps) or sham procedure. Additionally, 6 healthy animals underwent percutaneous-PADN to compare the pulmonary artery (PA) lesion generated with both approaches. In the surgical-PADN arm, hemodynamic evaluation and cardiac magnetic resonance (CMR) were performed at baseline and at 2 and 3-month follow-up. Histological assessment was carried out at the completion of the protocol. Eighteen pigs (6 following surgical-PADN, 6 sham and 6 percutaneous-PADN) completed the protocol. A complete transmural PA lesion was demonstrated using surgical clamps, whereas only focal damage to adventitial fibers was observed after percutaneous-PADN. In the surgical-PADN arm, the hemodynamic profile did not significantly differ between groups neither at baseline [mean pulmonary artery pressure (mPAP) median values of 32.0 vs. 27.5 mmHg, P = 0.394 and indexed pulmonary vascular resistance (iPVR) 5.9 vs. 4.7 WU m2, P = 0.394 for PADN/sham groups, respectively] nor at any follow-up (mPAP of 35.0 vs. 35.0 mmHg, P = 0.236 and iPVR of 8.3 vs. 6.7 WU m2, P = 0.477 at third month in PADN/sham groups, respectively). Surgical-PADN was not associated with any benefit in RV anatomy or function on CMR/histology. In a large-animal model of chronic postcapillary PH, transmural PADN with surgical clamps was associated with a neutral pulmonary hemodynamic effect.
Keywords: Denervation; Magnetic resonance imaging; Pulmonary hypertension; Treatment.