Device Near Carotids May Lower Blood Pressure

 

November 30, 2006

An implantable technology to control high blood pressure in patients not responding to available medicines has demonstrated initial favorable results in a study conducted at the University Hospital Berne in Switzerland. Developed by Minneapolis-based CVRx in 2002 and entering a clinical trial in the U.S., the tiny device - called the Rheos system - was first implanted in 11 patients undergoing surgery for carotid stenosis.

Dr. Jurg Schmidli and colleagues placed electrodes outside the carotid wall and applied electrical stimulation. The result, reports Newsday.com, was a swift drop in blood pressure. Stimulating the carotid sinus sends messages to baroreceptors in the brain that control blood pressure.

The study was expanded into a multicentered trial of 45 patients, 31 of whom have had surgery to place electrodes outside the carotid and to place an internal pulse generator into the chest wall. Dr. Schmidli operated on six of these patients. He has reported that the first 16 patients experienced an average drop of 29 millimeters of mercury.

"By comparison, if a drug reduced blood pressure by 9 millimeters it is considered major,� Dr. Schmidli said. "It is promising."

"This has tremendous potential," said Dr. Frank Veith, a professor of surgery at New York University School of Medicine who runs an annual scientific symposium for vascular surgeons in Manhattan. The Veith Symposium, now in its 33rd year, is attended by hundreds of surgeons worldwide. "It's early, but ultimately I think it may work," Veith said of the new device.