Renal denervation + PVI produce best outcomes for drug-resistant hypertension

MRI scans performed six months after ablation, demonstrating no evidence of renal artery stenosis. Source: J Am Coll Cardiol 2012;60(13)1163–1170.

Renal artery denervation reduces systolic and diastolic blood pressure in patients with drug-resistant hypertension, and reduces atrial fibrillation (AF) recurrences when combined with pulmonary vein isolation (PVI), according to a small double blind, randomized study published Sept. 25 in the Journal of the American College of Cardiology.

Many of these comorbidities or consequences of hypertension can predispose patients to a treatment-resistant disease state, according to the study authors. Also, hypertension is an important risk factor for developing AF, and the incidence of AF also increases with left ventricular hypertrophy, coronary heart disease and heart failure, all consequences of poorly controlled hypertension. They also noted that treating drug-resistant hypertension with renal denervation has been reported to control blood pressure, but any effect on AF is unknown.

Thus, Evgeny A. Pokushalov, MD, PhD, of the arrhythmia department at the State Research Institute of Circulation Pathology in Novosibirsk, Russia, and colleagues hypothesized that renal artery denervation could have a salutary effect on AF patterns in patients with poorly controlled hypertension by improving blood pressure control and by reduction in central sympathetic cardiac stimulation.

The researchers enrolled 27 patients, and 14 were randomized to PVI only, while 13 were randomized to PVI with renal artery denervation. The participants had a history of symptomatic paroxysmal or persistent AF refractory to at least two antiarrhythmic drugs and drug-resistant hypertension (with systolic blood pressure of more than 160 mm Hg, despite triple drug therapy). They followed all patients for at least one year to assess maintenance of sinus rhythm and to monitor changes in blood pressure.

At the end of the follow-up, Pokushalov et al observed significant reductions in systolic (from 181 to 156) and diastolic blood pressure (from 97 to 87) in patients treated with PVI with renal denervation without significant change in the PVI-only group.

Also, 69 percent of patients treated with PVI with renal denervation were AF-free at the 12-month post-ablation follow-up exam vs. 29 percent of patients in the PVI-only group.

Based on their “first-in-mean” study findings, the researchers suggested that the main findings of this prospective double-blind randomized study are:

1. Renal artery denervation had a positive impact on AF recurrences in hypertensive patients with refractory AF who also underwent PVI; and
2. Renal artery ablation resulted in sustained improvement in systolic and diastolic blood pressure control over one year of follow-up.

“Although the study was randomized and both the AF and blood pressure double-blind outcomes were markedly improved in the combined ablation group, the results will require validation in additional and larger trials,” Pokushalove et al concluded. “Because our data refer to a follow-up period of 1 year after the ablation procedure, we cannot extrapolate our results to the long-term maintenance of sinus rhythm or blood pressure control. Furthermore, the use of an implantable monitor might allow more accurate detection of AF recurrences than office ECG and 24-hour Holter monitoring.”