CardioExchange Archive

The already hot field of renal denervation for resistant hypertension just got a little hotter. With the announcement of a clinical trial powered to detect improvements in cardiovascular outcomes, St. Jude Medical has raised the stakes in the field and demonstrated a new level of commitment to the innovative new technology.

For the past few years interest in the new procedure — which uses a catheter to deliver radiofrequency energy to disrupt renal nerves in order to produce large drops in blood pressure — has been mounting in the cardiovascular community. Results from trials with Medtronic’s Symplicity system, the leader in the field, suggest that the procedure can safely cause significant and lasting drops in blood pressure in patients with hypertension resistant to traditional drug therapy. But the Medtronic trials were not designed to measure changes in cardiovascular outcomes. Although many experts believed the Symplicity device will gain FDA approval based on these blood pressure outcomes, the reliance on a surrogate endpoint instead of important clinical outcomes leaves the technology vulnerable to criticism.

St. Jude’s announcement today appears to address concerns about the limitations of surrogate endpoints. The EnligHTNment trial, using the company’s EnligHTN Renal Denervation System, “will evaluate whether patients with hypertension that are treated with renal denervation and medication experience additional benefits beyond a reduction in blood pressure,” according to the company. It will be “the first large-scale study that will examine the long-term effects of renal denervation in patients who have uncontrolled hypertension to see if renal denervation also reduces the risk of major cardiovascular events such as heart attack, stroke and death.” EnligHTNment will be an international, multi-center, randomized, controlled study, the company said.

“To date, the renal denervation studies that have been conducted only looked at reducing blood pressure in patients with uncontrolled or resistant hypertension,” said Michael Böhm, a principal investigator for the trial, in a St. Jude press release. “What we need to know is if this minimally invasive approach for treating hypertension also correlates to a reduction in major cardiac events such as heart attack, stroke and death, which are the primary risks for patients whose blood pressure is not well controlled.”

“Initial study results have demonstrated that the EnligHTN Renal Denervation System is safe and effective in rapidly lowering blood pressure. If these results extend into the prevention of major cardiac events, there is the potential to dramatically change how we treat these patients,” said Thomas Lüscher, also a principal investigator for the trial, in the press release.

St. Jude did not announce any details of the trial, though it is expected to take 5 years to complete. The trial appears likely to demonstrate the company’s confidence in the technology and, if successful, may help quiet skeptics and improve the reception of the device in the medical community.

Click here to read an interview with Murray David Essler, the Chief Investigator of Symplicity HTN-2.

will evaluate whether renal denervation and medication can provide health benefits to patients beyond lowering high blood pressurewill evaluate whether patients with hypertension that are treated with renal denervation and medication experience additional benefits beyond a reduction in blood pressure