Randomized trial gives procedure a boost
SAN FRANCISCO -- Adding renal artery denervation to atrial fibrillation (Afib, AF) ablation boosted its antiarrhythmic efficacy in a randomized trial reported here.
The combination increased freedom from atrial fibrillation recurrence at 12 months off antiarrhythmic drugs by a relative 43% (rate 72.1% vs 56.5%, P=0.004), Jonathan Steinberg, MD, of New York's University of Rochester School of Medicine & Dentistry, reported here at the Heart Rhythm Society meeting.
In the ERADICATE-AF trial, pulmonary vein isolation (PVI) plus denervation, mainly using a standard ablation catheter not specifically designed for renal use, appeared safe with a complication rate of 4.5% compared with 4.2% with Afib ablation alone.
Notably, blood pressure dropped by an average 16/11 mm Hg with the combination versus 2/2 mm Hg in the PVI-only group.
"Renal denervation is reasonable to employ to increase the success rate of AF ablation in patients with hypertension," Steinberg concluded at the late-breaking clinical trial session.
Session study discussant Cara Pellegrini, MD, of the University of California San Francisco and VA Medical Center there, said she was "quite impressed that despite the added complexity of an extra procedural component there appeared to be virtually no added risk."
She calculated a "pretty remarkable" number needed to treat of 6.1 to prevent a recurrence at 1 year.
However, Pellegrini pointed out that there was "still lots of AF. ... This is not a panacea."
Also, only 57% of the patients had successful renal denervation with high-frequency stimulation. "In light of the SYMPLICITY 3 [sic] trial, it would have been nice to see that number a little bit higher as a proof of mechanism, proof of impact, and complete denervation," she said.
The effect on blood pressure was greater than seen in recent systematic reviews, noted Andrew Krahn, MD, of the University of British Columbia in Vancouver and a moderator at the session.
"The burning question that we all have is: Is the effect of renal denervation essentially an antihypertensive effect, or is it an antiarrhythmic effect, or perhaps both?" Steinberg replied.
Studies in progressively less severe hypertension have shown improved AF outcome, and a trial is likely to be planned soon targeting patients with no hypertension to answer the question, he noted.
Krahn countered at the press conference that there are also trials ongoing of aggressive blood pressure control as part of Afib management without renal denervation.
The ERADICATE-AF trial included 302 symptomatic paroxysmal Afib patients randomized to PVI alone or with renal artery denervation at centers in Europe and the Russian Federation. Patients also had to have a blood pressure of at least 130 mm Hg systolic or 80 mm Hg diastolic on antihypertensive medication (median two drugs, all with an ACE inhibitor or ARB). Impaired renal function or unsuitable renal artery anatomy made patients ineligible for the trial.
PVI used the Arctic Front Advance cryoballoon confirmed by multi-electrode mapping catheter and cavotricuspid isthmus ablation if there was clinical or induced atrial flutter.
The renal denervation procedure was done single-blind after PVI and, for 96% of patients, used radiofrequency energy to the bilateral main renal arteries, point by point, at 8-12 W with an irrigated tip catheter. It was done under 3-D reconstruction guidance.
It was a single-blind trial, with patients sedated for the procedure and thus unaware of their study arm. While sham control has been a pivotal issue in renal denervation trials, "essentially we did a sham control study because all patients had an intravascular procedure and, from their perspective, they were not aware of what parts of the procedure were [being] done on them," Steinberg told MedPage Today at a press conference.
One limitation, noted press conference panelist Roderick Tung, MD, of the University of Chicago, was that the study locations made for a highly Caucasian study population, which was tied to higher efficacy rates versus sham in SYMPLICITY HTN-3.
Steinberg disclosed relationships with Medtronic, Biosense Webster, National Cardiac, Allergan, G Medical, AtriCure, Corfigo, Omron, AliveCor, the National Institutes of Health, and the American Board of Internal Medicine.
Pellegrini disclosed no relevant relationships with industry.
Heart Rhythm Society
Source Reference: Steinberg JS, et al "Evaluate Renal Artery Denervation In Addition to Catheter Ablation To Eliminate Atrial Fibrillation (ERADICATE-AF) Trial" HRS 2019; Abstract LBCT01-03.
Read the original article on Medpage Today: Renal Denervation May Boost Afib Ablation Efficacy