Doctor Designs Biventricular Pacemaker
by July 23, 2001 12:00 am 55 views
This fall, the U.S. Food and Drug Administration will probably approve a new pacemaker designed for correcting a specific complication of congestive heart failure. But, a cluster of patients at Northwest Medical Center in Springdale couldn’t wait. Standard medical practices had failed them, and time for a solution dwindled.
Dr. Michael Green solved the problem by designing a biventricular pacemaker in true “MacGuyver” style. Using a piece of hardware similar to that found at Radio Shack or The Home Depot, Green fitted a standard pacemaker with a Y-adapter. (He ordered his from a medical supplier.)
“We had patients failing,” Green said. Now, more than 20 patients at Northwest Medical have received the modified pacemaker, and the doctor said all have seen successful results.
“It’s been a huge success,” he said.
Each patient who benefitted from Green’s altered pacemaker suffered from delayed electrical activation — a bundle branch block — which stops the heart chambers from contracting in a synchronized fashion. Basically, the situation caused the heart to slosh blood around inside the chambers rather than pump efficiently.
Green wanted to improve the heart’s ability to pump by repairing the electrical delay. To do this, the patients needed stimulation for the left ventricle, too.
Generally, pacemakers feature outlets for two leads, or wires, that run from the case into the heart’s right ventricle and atrium. About the width and depth of three fingers, typical pacemakers are inserted under the skin of a patient, just below the collarbone. From there, the device prompts the heart to maintain smooth rhythm.
To regulate the hearts of patients with the electrical malfunction, Green created a biventricular pacemaker. He equipped a standard appliance with a Y-adapter, which added a third lead that reaches around the heart to synchronize both ventricles. Green threads the additional lead through the coronary sinus, a large vein that encircles the heart like a belt.
“It’s like threading rope through a garden hose, only smaller,” Green said.
The first time he performed the procedure, the process took 2.5 hours, compared to the 30-45 minutes needed to implant a typical pacemaker. He has now cut that time to 1.5 hours. The additional time increased the cost of the procedure by a few hundred dollars, Green said.
The doctor’s technical adaptation has saved lives in Northwest Arkansas, but the repair was only meant to be a temporary mend until the FDA approves a newer pacemaker.
Green said the updated pacemaker will come equipped with three lead outlets and a defibrillator.
Medtronic, a publicly-held medical technology company based in Minneapolis, Minn., has submitted a new pacemaker for FDA approval. The biomedical corporation employs 25,000 people and supplies Northwest Medical’s pacemaker hardware.
Patients using Northwest Medical’s biventricular pacer must change the battery in the pacemaker case within 3-4 years of the implant. At that time, Green said, the patients will likely upgrade to the newer device.
Green said the biventricular pacemaker increases the patient’s quality of life and decreases the chances of a quick return to the hospital.
Originally from Huntsville, Green also helped start the Congestive Heart Failure Center at Northwest Medical.
The clinic tries to prevent repeat hospital stays by teaching patients how to manage their condition.