Renal denervation found less efficacious in patients with accessory renal arteries

Individuals with resistant hypertension and accessory renal arteries who underwent catheter-based renal sympathetic denervation experienced less pronounced decreases in BP at 6 months compared with those who had a bilateral single renal artery.

Researchers of the study published in the Journal of American College of Cardiology: Cardiovascular Interventions enrolled 74 patients with resistant hypertension to compare the BP-lowering effect of catheter-based renal sympathetic denervation in patients with accessory renal arteries with that reported in individuals with bilateral single renal arteries.

There were 54 patients with bilateral single renal arteries in one group and 20 patients with accessory renal arteries in the second group. Further breakdown included nine patients in the second group who had denervated accessory renal arteries and 11 patients in that group with non-denervated or incompletely denervated accessory renal arteries.

The change in office systolic BP after 6 months served as the primary outcome measure.

The researchers reported success in all patients.

In the first group, baseline mean BP decreased from 166.2/89.4 ± 20.5/14.6 mm Hg by –16.6 (P<.001)/–6.7 (P=.016) ±16.4/11 mm Hg at 6-months follow-up.

In the second group, a mean baseline BP of 164.2/89.1 ± 19.9/15.4 mm Hg was reported. Six-month follow-up results indicated a decrease of –6.2 (P=.19)/–0.2 (P=.5) ± 19.7/11.3 mm Hg.

An office BP reduction of –8.8 (P=.2)/1.1 ± 17.9/10.8 mm Hg occurred in patients in the second group with denervated accessory renal arteries. In the other 11 patients in the second group, a decrease of –4.1 (P=.55)/–1.3 ± 20.8/11.6 mm Hg occurred.

The first group also demonstrated significant decreases in 24-hour mean systolic BP of –8.3 ± 17.4 mm Hg (P<.01). This effect did not occur in the second group (–3.7 ± 8.3 mm Hg; P=.38).

“BP reduction achieved after renal denervation in patients with accessory renal arteries is less pronounced than in patients with bilateral single renal arteries,” the researchers concluded.

Felix Mahfoud

In an editorial accompanying the paper, Felix Mahfoud, MD, of the Klinik für Innere Medizin III at the Universitätsklinikum des Saarlandes in Homburg/Saar, Germany, and Deepak L. Bhatt, MD, of Brigham and Women’s Hospital and Harvard Medical School in Boston, described the observations of the present study as “valuable.”

“The authors concluded that ablation of accessory arteries of >3.5 mm appears to be safe and complete denervation should be attempted whenever possible,” wrote Mahfoud and Bhatt, who is the chief medical editor of Cardiology Today’s Intervention. “However, one should keep in mind that the patients did not undergo rigorous routine renal artery imaging (by CT or MRI) during follow-up, and given the fact that especially small renal arteries (<4 mm) tend to develop severe spasms after radiofrequency ablation, renal artery stenosis or flow limiting obstruction could have been missed during follow-up.”

Deepak L. Bhatt

The editorialists wrote that the paper offers new perspective on the proportion of patients with resistant hypertension considered for renal denervation who have accessory arteries. It also offers insight into the role these arteries play in BP regulation. “Yet, before definitive statements regarding the importance of complete and incomplete denervation in accessory renal arteries can be made, the findings need to be confirmed in a larger set of patients,” they wrote.

For more information:

Id D. J Am Coll Cardiol Intv. 2013;6:1085-1091.

Mahfoud F. J Am Coll Cardiol Intv. 2013;6:1092-1094.

Disclosure: One researcher reports financial relationships with companies including Abbott, Access Closure, AGA Medical, Angiomed, Aptus, Arstasis, Atritech, Atrium, Avinger, Bard, Boston Scientific, BridgePoint Medical, Cardiac Dimensions, CardioKinetix, CardioMEMS, Coherex, Contego, Cardiovascular Systems, CVRx, EndoCross, EndoTex, Epitek, ev3, FlowCardia and Gore. All other researchers report no relevant financial disclosures. Mahfoud and Bhatt report a number of financial relationships with companies including Medscape Biosciences, Medtronic, ReCor, St. Jude and Vessix. See study and editorial for a full list of financial disclosures.