The Detroit Medical Center (DMC) Cardiovascular Institute (CVI) and the Wayne State University School of Medicine have begun enrolling patients in a pioneering new study that could lead to a dramatic breakthrough in the battle against treatment-resistant hypertension . . . a chronic ailment that currently poses a major health threat to more than six million Americans and 100 million people worldwide.
The recently launched clinical trial will evaluate the safety and effectiveness of this investigational therapy to treat patients with treatment-resistant hypertension. These patients may be at risk for heart attacks, strokes and other life-threatening cardiovascular disorders triggered by high blood pressure that can’t be treated by conventional blood-pressure medications, said health experts at both the DMC and Wayne State.
“We’re feeling very hopeful about this new study because it could lead to a new and innovative approach for treating the growing number of treatment-resistant hypertension patients in the U.S., which is especially critical to African-Americans living in urban settings like Detroit, who may be at greater risk,” said Theodore L. Schreiber, MD, the president of the CVI. “This pioneering new national clinical study – in which the CVI will play a key role – will allow us to test the effectiveness of a recently developed method for reducing treatment-resistant high blood pressure in patients for whom blood pressure medications have not been effective.”
Dr. Schreiber pointed out that 28 percent of patients who struggle with chronic hypertension are treatment-resistant” – meaning they cannot be helped much by traditional medications aimed at treating the condition.
“Obviously, this represents a very large percentage of hypertension patients,” said Dr. Schreiber, “and the early clinical results from testing in Europe and elsewhere now suggest that renal deneravation may be a safe and effective option for patients to manage treatment-resistant hypertension.”
Known as the “SYMPLICITY HTN-3 Study,” the clinical trial will evaluate the safety and effectiveness of a procedure called renal denervation, which aims to deactivate overactive nerves in the renal artery leading to the kidney – a major cause of hypertension in many patients. To begin the procedure, clinicians insert a flexible catheter into the femoral artery via a tiny incision in the thigh.
After that, a radio-energy-bearing device inside the catheter will be threaded through the arteries into position near the targeted renal artery to deliver radio waves that will effectively neutralize the over-active nerves in large part responsible for the disorder.
Treatment-resistant hypertension is defined as systolic blood pressure that remains high (greater than 140/90 mmHg) despite treatment with three or more antihypertensive medications.
These patients have a threefold increase in the risk of cardiovascular events compared with individuals with controlled high blood pressure.
Renal denervation is a minimally invasive, catheter-based procedure that, in effect, better regulates the output of nerves that line the walls of the arteries leading to the kidneys. These nerves are part of the sympathetic nervous system, which is one of the ways the body manages blood pressure. In people with hypertension, however, the renal nerves are often hyperactive.
The SYMPLICITY HTN-3 study is a randomized, controlled trial designed to evaluate the safety and effectiveness of renal denervation with the investigational Symplicity renal denervation system in patients with treatment-resistant hypertension and systolic blood pressure higher than 160 mmHg.
The study will enroll approximately 530 patients across several US medical centers. People receiving the investigational treatment will be compared with a control group that does not, with all patients continuing to take their blood pressure medications. Patients enrolled in the SYMPLICITY HTN-3 trial will be randomly assigned to a group, with two out of three assigned to the treatment group and one out of three assigned to the control group. Those in the control group may receive the treatment after a six-month period. The primary endpoints of the study are the change in blood pressure from baseline to six months and incidence of major adverse events.
“This study has a unique design, since patients in the control group may have the option to receive renal denervation treatment six months following randomization, which may help extend the potential benefit of renal denervation to all participants in the trial if the trial demonstrates benefit,” said John M. Flack, MD, MPH, professor and Chair of WSU Internal Medicine, as well as the Chief of the Division of Translational Research and Clinical Epidemiology.