SYMPLICITY Study to Research Experimental Treatment for Resistant High Blood Pressure
The University of Michigan Cardiovascular Center will participate in the SYMPLICITY HTN-3 national clinical trial which will examine an investigational technique for treating high blood pressure that has been resistant to multiple medications.
Transcatheter renal denervation is a novel therapy for treatment of resistant hypertension. It is not yet approved in the United States by the Food and Drug Administration, but has been commercially available in Europe and Australia since April 2010 and has successfully treated more than 4,000 patients, according to findings presented to the European Society of Cardiology (ESC).
“There are nearly six million Americans who are unable to get their blood pressure under control despite treatment with three, four, five or six blood pressure medications,” says U-M cardiologist and co-principal investigator Robert Brook, M.D. “This investigational treatment may represent a new and innovative approach to help patients reach their target blood pressure levels.”
Blood pressure measurements identify the pressure placed on the arteries during and after each heartbeat. It is reported as two numbers (ie: 120/80). The top number (systolic pressure) measures the pressure when the heart muscle contracts. It should not be higher than 120 mm/Hg. The bottom number represents diastolic pressure, or the pressure on the blood vessels while the heart is at rest. This should be no greater than 80.
Patients whose blood pressure remains high – greater than 140/90 – despite taking as many as three to five medications, are considered to have treatment-resistant hypertension. This chronic condition places the patient at serious risk for stroke, heart attack, heart failure, and kidney disease.
The SYMPLICITY HTN-3 study will continue to evaluate the safety and effectiveness of the transcatheter renal (kidney) denervation procedure. This system uses a catheter and a radiofrequency generator to deliver short bursts of energy to the renal sympathetic nerve to disrupt activity and reduce its effect on blood pressure. Elevated (overactive) sympathetic nervous system activity is a key factor in hypertension.
Previous studies have shown that renal denervation (RDN) can lead to significant and sustained blood pressure reduction for up to 18 months in patients with treatment-resistant hypertension. The SYMPLICITY HTN-2 trial involved just over 100 patients at 24 centers in 11 countries who all had high blood pressure (greater than 160 systolic), despite an average daily regimen of five anti-hypertensive medications. Those receiving the experimental treatment had an average blood pressure reduction of 32 mm/Hg systolic and 12 mm/Hg diastolic pressure from baseline.
For more information about the SYMPLICITY HTN-3 trial, go to UMClinicalstudies.org, Renal Denervation in Patients with Uncontrolled Hypertension (HUM00057579), or call (734) 232-4277. The clinical trial is sponsored by Medtronic, Inc, a global leader in medical technology.
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Symplicity HTN-2 Investigators, Esler MD, Krum H, Sobotka PA, Schlaich MP, Schmieder RE, Böhm M. Renal sympathetic denervation in patients with treatment-resistant hypertension (The Symplicity HTN-2 Trial).Lancet, 2010;376:1903-1909
Transcatheter Renal Denervation by Subhash Banerjee MD. The Journal of Invasive Cardiology (online) at www.invasivecardiology.com