ESC Issues Consensus Document on Catheter-Based Renal Denervation

April 25, 2013—The European Society of Cardiology (ESC) announced the publication of a European expert consensus document on catheter-based renal denervation. Endorsed by the ESC and the European Association of Percutaneous Cardiovascular Interventions, the document by Felix Mahfoud, MD, et al is available online ahead of print in the European Heart Journal.

Dr. Mahfoud, who is an interventional cardiologist at the Klinik für Innere Medizin III Kardiologie, Angiologie und Internistische Intensivmedizin of the Universitätsklinikum des Saarlandes in Homburg/Saar, Germany, noted in the announcement, “We treated the first patient 3 years ago and so far there is no sign of renervation. Long-term follow-up of these patients is needed.”

According to the ESC press release, the paper provides guidance on patient selection, center selection, efficacy, safety, limitations, and potential new indications for referring physicians, interventionists, and healthcare providers. The society noted that clinical trials show that catheter-based renal denervation reduces blood pressure in patients who do not respond to conventional drug therapy; use of this this technique is increasing in Europe and worldwide, and several national societies have published guidance on which patients with hypertension should receive treatment.

The ESC advised that approximately 10% of patients with high blood pressure are resistant to treatment, which puts them at increased risk of cardiovascular events, including heart attacks. Additionally, increased activity of the sympathetic nervous system occurs in other conditions, including heart failure, diabetes, arrhythmias, chronic kidney disease, and obstructive sleep apnea. Pilot studies indicate that renal denervation may be an effective therapy for these conditions.

As summarized in the ESC announcement, the paper states that renal denervation in Europe is currently indicated for blood pressure control in patients with treatment-resistant hypertension (defined as systolic blood pressure > 160 mm Hg or > 150 mm Hg in type 2 diabetes) despite treatment with at least three antihypertensive drugs of different types in adequate doses (including one diuretic) and lifestyle modification. The paper advises that screening should be conducted to exclude patients with secondary causes of hypertension that are potentially curable.

The consensus publication further states that centers should be specialized in the management of hypertension. At least one hypertension expert should be involved in treatment and screening. The intervention should be performed by interventional cardiologists or angiologists with training in percutaneous renal artery access. Centers should perform more than 25 renal artery interventions per year to ensure they have the required experience.

The Symplicity HTN-1 trial of the Symplicity catheter system (Medtronic, Inc., Minneapolis, MN) showed that renal denervation had a sustained blood pressure-lowering effect over 3 years, but longer efficacy data is needed, stated the ESC consensus document.

The Symplicity HTN-1 data were presented in October at TCT 2012: Transcatheter Cardiovascular Therapeutics conference in Miami, Florida and published in the TCT 2012 supplement of the Journal of the American College of Cardiology by Professor Henry Krum, MD, et al.

Commenting on the document in the ESC press release, Dr. Mahfoud stated, “The hope is that insurance companies and healthcare providers will read it and will only pay for those centers and especially for those patients who fit the criteria published in the paper. The problem right now is that there are no European criteria for determining which patients are most likely to benefit and which centers have the necessary experience.” He added, “We have known for decades that high sympathetic activity could be a target for treatment, but until now, we haven't had a way to do it. We now have a new treatment modality which allows us to reduce sympathetic activity, and I'm optimistic that we will get new indications for renal denervation.” Dr. Mahfoud also advised that trials have not investigated the possibility of reducing pill burden, and so patients must continue with an antihypertensive medication regimen.