Lowering Blood Pressure: Drug Free - Vascular Surgeons Lower Blood Pressure With Implanted Device

September 1, 2005 — A new cell phone-sized implant can keep blood pressure in check from within the chest, just like a pacemaker controls heartbeats. When the device detects a rise in pressure, it sends electrical signals to the brain via the carotid arteries in the neck. The brain then signals the body's own natural system to reduce blood pressure.

High blood pressure is a problem for millions of people. Previously, medication and diet were all doctors had to control it. Now a new device can help lower blood pressure and keep people alive and active longer.

Baby Jamier is Annette Lawrence's pride and joy, but until now she didn't have enough energy to enjoy her new grandson. "Before I couldn't even get out of bed. I couldn't really do anything."

At just 37, she lived every day with life-threatening high blood pressure. Karl Illig, a vascular surgeon at the University of Rochester Medical Center in Rochester, N.Y., says, "She constantly had blood pressure up in the 200s." Dr. Illig was the first doctor in the nation to try the new device. "[The device] is basically like a pacemaker. That's the best way to look at it."

The Rheos Baroreflex Hypertension System is saving Lawrence's life. It is as small as a cell phone and inside her chest. The device works by sending electrical impulses to the carotid arteries in the neck. "That electrical signal is then sent up the nerves into the brain telling the brain, 'Ah ha! Your blood pressure's too high,'" Dr. Illig explains. Then, the brain sends signals to decrease the heart rate, open blood vessels, and release more fluid from the kidneys, activating the body's existing system to naturally reduce blood pressure.

Dr. Illig says, "The blood pressure really is too high, but the brain doesn't sense it that way so this is kind of giving it a kick start." With the device turned off, Annette's blood pressure is 175/ 104. When it's turned on, her blood pressure drops to 143/ 86 -- right on track. "Since I had this procedure done, boy I tell ya, I've got so much energy. I'm ready to keep up with [my grandson]," Laurence says.

The risks of receiving the system are relatively low. Patients are put under a general anesthesia and undergo a two-to three-hour operation. So far, there are no visible side effects to the system. This device is not for everyone. Patients must have tried and failed all other medications.

BACKGROUND: Researchers have developed an implantable device that lowers blood pressure by activating the body's natural blood pressure regulation systems, rather than relying on drugs. It is currently in clinical trials at the University of Rochester Medical Center, among other locations around the country.

HOW IT WORKS: The Rheos system electrically activates the body's system for regulating blood pressure. Electrical signals are sent to the central nervous system, and the body interprets this as a rise in blood pressure. So the brain counteracts this by sending signals in response to dilate blood vessels. This allows blood to flow more freely, reducing the heart rate and encouraging the kidneys to release fluid. The Rheos system consists of a battery-operated implantable generator, inserted under the skin near the collarbone, and two "leads" that run from the generator to left and right carotid sinus in the neck.

BENEFITS: Reducing blood pressure is associated with lowering the risk of stroke, heart attack, heart failure and kidney disease. The device offers hope to patients who have not been able to control their blood pressure with medications.

WHAT IS BLOOD PRESSURE: Blood pressure is the force in the arteries when the heart beats, and when the heart is at rest. When blood pressure is high, there is an increased risk of heart disease (which leads to heart attack) and stroke. It is most common in adults over age 35, and is especially prevalent in African Americans, the middle-aged and elderly, obese people, heavy drinkers, and women who are taking birth control pills. Those with diabetes, gout or kidney disease are also prone to suffer from high blood pressure.

Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.

Note: This story and accompanying video were originally produced for the American Institute of Physics series Discoveries and Breakthroughs in Science by Ivanhoe Broadcast News and are protected by copyright law. All rights reserved.