November 12, 2008 - Clinical data presented at the American Heart Association 2008 Scientific Sessions this week on the use of the CVRx Rheos implantable system designed to treat hypertension and heart failure, shows Rheos Therapy significantly improved heart structure and function in patients with high blood pressure.
The system uses CVRx-patented Baroreflex Activation Therapy technology, which activates the carotid baroreceptors, central components of the body's natural cardiovascular regulation system. When the baroreceptors are activated, signals are sent through neural pathways to the brain and interpreted as a rise in blood pressure. The brain works to counteract this perceived rise in blood pressure by sending signals to other parts of the body (heart, blood vessels and kidneys) that relax the blood vessels and inhibit the production of stress-related hormones. These changes enable the heart to increase blood output, while maintaining or reducing its workload, thereby reducing blood pressure when it is elevated and alleviating the symptoms of heart failure.
The system uses a small device that is implanted under the collar bone. Two thin lead wires that are implanted at the left and right carotid arteries and connected to the pulse generator. Doctors can noninvasively regulate the signals using Rheos Programmer System.
Peter W. de Leeuw, M.D., professor of medicine and hypertension at the University of Maastricht in The Netherlands, presented the data on Nov. 11 at AHA 2008 in New Orleans. In addition, data from a pre-clinical study indicate that, after receiving Rheos Therapy, canines with heart failure were less likely to be induced into lethal ventricular heart rhythms, a risk factor for sudden cardiac arrest.
Clinical data demonstrate continuous use of Rheos Therapy in 33 Stage II hypertension patients remodels cardiac structure and improves heart function. Specifically, the Rheos Therapy increased the left ventricular outflow tract diameter and decreased the size of the heart over a 12-month period. These changes reduce the amount of energy the heart uses to meet the needs of the body, and decreases stress on the heart.
"We are optimistic that the Rheos System will prove to be an effective means of treating hypertensive patients with left ventricular hypertrophy," said Dr. de Leeuw. "From the current clinical trial, we are expanding our evaluation of the Rheos System and finding that not only does this unique therapy lower blood pressure, but it improves the efficiency of transferring blood from the heart to the arteries. This opens up the possibility to use of the device in patients with heart failure."
Mengjun Wang, M.D., and Hani Sabbah, M.D., discussed data, which show canines with heart failure are less likely to be induced into lethal ventricular heart rhythms, which can lead to sudden cardiac death, after long-term use of Rheos Therapy. At six months, the seven canines implanted with the Rheos device were much less likely to be induced into ventricular tachyarrythmias (excessively rapid heart rate) during programmed stimulation, than the four canines without a Rheos device implanted.
CVRx initially evaluated the Rheos System as a treatment for hypertension or high blood pressure. Many patients enrolled in early clinical evaluations of the Rheos System suffered from hypertension and had abnormal heart structure and function. Both conditions improved with Rheos Therapy in many of these patients, the company said.
CVRx received investigational device exemption (IDE) approval from the FDA to begin the Rheos pivotal trial to evaluate the safety and effectiveness of the Rheos System in treating hypertension. The trial is enrolling 300 patients at multiple clinical sites in the U.S. and in Europe.
For more information: www.cvrx.com, www.bloodpressuretrial.com