Experimental Device To Treat High Blood Pressure
By: Charlotte Ames
Updated: February 26, 2010
According to the American Heart Association, about one in three Americans (roughly 74.5 million adults) has high blood pressure. The condition affects about half of people over 60. African Americans have the highest rate of high blood pressure among all ethnic groups in the U.S., and are more likely to develop the condition at a younger age.
Over time, the extra force of blood pressure damages the walls of the arteries. The condition can lead to scarring on the blood vessel walls, increased risk for clots, build-up of plaque and damage to vital organs (like the heart, brain and kidneys). The heart has to work harder to get blood through the body, which may lead to heart failure. High blood pressure also increases the risk for heart attack, stroke, kidney damage, vision loss and, in men, erectile dysfunction.
The body has its own natural system for regulating blood pressure, called the baroreflex. Special pressure sensors (baroreceptors) are located in the carotid artery and carotid sinus in the neck. These sensors detect blood pressure levels and send the information to the brain. The brain then determines if measures need to be taken to adjust blood pressure.
Researchers are now trying to determine if they can use the body’s own baroreflex for patients with treatment-resistant high blood pressure. In this condition, blood pressure remains high, even after treatment with three different high blood pressure medications.
The study is called the Rheos® Pivotal Trial. The Rheos System consists of a pulse generator, wire leads and a programmer. The wire leads are wrapped around the carotid arteries on the left and right sides of the neck (near the natural baroreceptors). The other ends of the wires are connected to the pulse generator, a battery powered pack implanted under the skin in the upper chest.
Marcos Rothstein, M.D., Nephrologist with Washington University in St. Louis says, once the device is programmed, the pulse generator delivers energy through the wires to the baroreceptors. This current “fools” the receptors into believing blood pressure is much higher than it really is. Hopefully, the body responds by sending signals that cause the blood pressure to decrease.
Rothstein says, initially, investigators were afraid the body would become accustomed to the Rheos System and the stimulation would no longer have any effect in blood pressure reduction. However, researchers have found the system provides beneficial treatment even in those who were implanted four to five years ago. In fact, patients appear to get better control over their blood pressure over time and doctors may be able to reduce the voltage delivered by the pulse generator. For information on the technology, go here .


