Future of Renal Denervation Considered at EuroPCR

May 23, 2014—At the annual EuroPCR conference, Felix Mahfoud, MD, and Konstantinos Tsioufis, MD, reflected on the potential future role of modulation of the sympathetic nervous system in patients with difficult-to-control hypertension. Dr. Mahfoud is from the University Hospital in Homburg, Germany. Dr. Tsioufis is from the University of Athens in Athens, Greece. The EuroPCR 2014 congress was held May 20–23 in Paris, France. EuroPCR is the official annual meeting of the European Association for Percutaneous Cardiovascular Interventions, a registered branch of the European Society of Cardiology.

As summarized by the EuroPCR press release, in the context of the SYMPLICITY HTN-3 clinical trial results, questions have been raised about the extent of the efficacy of renal denervation to treat uncontrolled hypertension, although the randomized, controlled trial confirmed the safety of renal denervation. The SYMPLICITY HTN-3 clinical trial results were presented in March 2014 at ACC.14, the 63rd annual scientific sessions of the American College of Cardiology, and published in The New England Journal of Medicine (2014; 370:1393-1401).

In the EuroPCR announcement, Dr. Tsioufis stated, “In terms of efficacy, some studies have shown that renal denervation can achieve a clinically relevant reduction of office and ambulatory blood pressure in patients with difficult-to-control hypertension. There is a need for more research to identify the pathophysiology of the condition and to select the best patients who will benefit from treatment with the procedure.”

Dr. Mahfoud added that the safety of renal denervation has never been contested, as the primary safety endpoint of the study was met, and although renal denervation with radiofrequency did not show a significant difference with regard to the efficacy endpoint compared to the control group, it is unlikely that the procedure does not work in humans. 

They noted that other aspects to be considered include that SYMPLICITY HTN-3 may be underpowered; antihypertensive drugs may have been maximized, but not stabilized; the patient population may differ from Caucasians recruited in previous trials; the results may just be accidental; and the procedure may not have been performed effectively. 

Additionally, the underlying pathophysiology is much more complex than initially thought. “Maybe we are moving away from Symplicity to complexity, in terms of how we deliver energy and where the sweet spots for renal denervation are. On top of it, there may be a learning curve for renal denervation; there is a lot more to learn and a lot more to understand,” concluded Dr. Mahfoud. 

In the conference announcement, EuroPCR course codirector William Wijns, MD, noted, “Renal denervation was developed as a promising therapy for the treatment of patients who suffer from resistant hypertension lacking treatment alternatives.” The physicians all agreed that this condition represents an unmet clinical need, adding that up until now, data from clinical trials and registries confirmed that renal denervation is a safe procedure. Furthermore, they stated that renal denervation is an option in patients with difficult-to-control hypertension, in whom other treatments have failed.