Radiofrequency (RF) renal denervation (RDN) was associated with reductions in renal sympathetic activity, inhibition of the renin-angiotensin system, increases in circulating B-type natriuretic peptide levels, and improvements in left ventricular (LV) activity and coronary vascular function in a swine model of heart failure with reduced ejection fraction (HFrEF), according to a study published in the Journal of the American College of Cardiology.
Yucatan miniswine between the ages of 9 and 10 months that were subjected to myocardial ischemia and reperfusion injury (MI/R) were included in the study (n=25). Swine had an LV ejection fraction (LVEF) <40%, signifying HFrEF.
During an 18-week follow-up period, the model underwent bilateral RF-RDN (n=10) or sham RDN intervention (n=11) at 6 weeks post-MI/R. Researchers evaluated cardiac function before and after MI/R with the use of transthoracic echocardiography every 3 weeks and at 18 weeks.
Compared with the sham control, the investigators observed noticeable reductions in renal norepinephrine levels and circulating angiotensin I (>12-fold reduction; P <.02) and angiotensin II (>6-fold reduction; P <.03) in swine that underwent RF-RDN. A 72% and 77% reduction in kidney dopamine and kidney norepinephrine was observed after RF-RDN (P <.01).
In addition, LV end-systolic volume was reduced significantly with RF-RDN, even more so than in the sham intervention. This resulted in a sustained improvement in LVEF. Animals in the RF-RDN group also experienced reductions in LV fibrosis as well as improvements in coronary artery responses to vasodilator therapy and improvements in LV longitudinal strain.
The limited follow-up duration as well as the use of an animal-only model represented the primary limitations of the analysis.
“Clinical studies are needed to assess whether these observations can be translated to patients with [heart failure] in the presence and absence of hypertension and assess the durability of whatever benefit occurs,” the researchers concluded.
Sharp TE III, Polhemus DJ, Li Z, et al. Renal denervation prevents heart failure progression via inhibition of the renin-angiotensin system. J Am Coll Cardiol. 2018;72(21):2609-2621.