Pulmonary and Systemic Hemodynamics following Multielectrode Radiofrequency Catheter Renal Denervation in Acutely Induced Pulmonary Arterial Hypertension in Swine

Abstract

Objective. We aimed to assess the effects of renal denervation (RDN) on systemic and pulmonary hemodynamics in a swine model of thromboxane A2- (TXA2-) induced pulmonary arterial hypertension (PAH). Methods. The study protocol comprised two PAH inductions with a target mean pulmonary artery pressure (PAP) of 40 mmHg at baseline and following either the RDN or sham procedure. Ten Landrace pigs underwent the first PAH induction; then, nine animals were randomly allocated in 1 : 1 ratio to RDN or sham procedure; the second PAH induction was performed in eight animals (one animal died of pulmonary embolism during the first PAH induction, and one animal died after RDN). In the RDN group, ablation was performed in all available renal arteries, and balloon inflation within artery branches was performed in controls. An autopsy study of the renal arteries was performed. Results. At baseline, the target mean PAP was achieved in all animals with 25.0 [20.1; 25.2] mcg of TXA2. The second PAH induction required the same mean TXA2 dose and infusion time. There was no statistically significant difference in the mean PAP at second PAH induction between the groups ( 39.0 ± 5.3 vs. 39.75 ± 0.5 mmHg, P > 0.05 ). In the RDN group, the second PAH induction resulted in a numerical but insignificant trend toward a decrease in the mean systemic blood pressure and systemic vascular resistance, when compared with the baseline induction ( 74 ± 18.7 vs. 90.25 ± 28.1 mmHg and 1995.3 ± 494.3 vs. 2433.7 ± 1176.7 d y n ∗ sec ∗ c m − 5 , P > 0.05 , respectively). No difference in hemodynamic parameters was noted in the sham group between the first and second PAH induction. Autopsy demonstrated artery damage in both groups, but RDN resulted in more severe lesions. Conclusions. According to our results, RDN does not result in significant acute pulmonary or systemic hemodynamic changes in the TXA2-induced PAH model. The potential chronic effects of RDN on PAH require further research.

Experience of using multielectrode catheter systems to perform radiofrequency renal sympathetic denervation in patients with resistant hypertension: immediate procedural effects

“…Например, был описан редкий (1 на 153 процедуры) случай формирования двухстороннего стеноза ПА после РД [29]. Уместно упомянуть о низкой чувствительности ультразвукового метода при обнаружении субклинических поражений ПА в послеоперационном периоде [30][31][32]. Хорошо известно, что атеросклеротическое поражение после повреждения эндотелия может прогрессировать медленно до клинически очевидных проявлений.…”

Laser renal denervation: A comprehensive evaluation of microstructural renal artery lesions

“…Therefore, laser RDN in three animals would result in about 150–200 nerves damaged (2 arteries and 2 applications per artery). Based on our preliminary experimental data, laser ablation in middle‐sized arteries resulted in almost circumferential lesions, whereas bipolar RF ablation had spot‐like lesions with a limited area of damage (Condori Leandro, 2021; Sagerer‐Gerhardt, 2021; Vakhrushev, 2021). Therefore, bipolar RF ablation required 3–4 times more applications than laser ablation to achieve the same area of damage, and the number of renal arteries in the RF ablation group would need to be larger by at least 2 times.…”

“…All procedures were performed under general anesthesia, as described earlier (Goncharova, 2021; Vakhrushev, 2021). Briefly, sedation was performed using an intramuscular injection of 1.5 mL Zoletil 100 (Virbac, Carros, France), and the outer ear vein was cannulated for drug infusion.…”

“…The procedure was recently described in detail elsewhere (Vakhrushev, 2021). After contrast angiography, a multielectrode balloon catheter for bipolar RF ablation (Vessix™, Boston Scientific, MA) was positioned into the left and right RA lumen using a 0.014‐in.…”

“…Kidneys were cut along the main artery branches and potential kidney injury was visually assessed. Visually detected lesions were calculated and excised within normal tissue (3–5 mm borders around a lesion) through all artery wall layers (intima, media, adventitia, and perivascular fat tissue) and prepared in paraffin blocks, as described previously (Vakhrushev, 2021).…”