At a time when drug-coated stents are losing popularity following concerns over safety issues, the Cleveland Clinic in US is exploring the possibility of using electrodes instead.
While the drug-coated stents adopt a biological approach, releasing medicine as they do gradually to prevent reclogging of arteries after angioplasty, the new method is touted as a neurological approach.
Coronary angioplasty is a medical procedure in which a balloon is used to open a blockage in a coronary (heart) artery narrowed by atherosclerosis. This procedure improves blood flow to the heart. Atherosclerosis is a condition in which a material called plaque builds up on the inner walls of the arteries. It is after angioplasty drug-coated stents are put in place in order toprevent reclogging of the cleared arteries.
Dr. Ali Rezai, director of Cleveland Clinic's Neurological Restoration department, said electrodes could supplant drugs embedded on the stents. Electricity is delivered to the site directly in order to activate or shut down nerves surrounding the arteries and thus regulate the function of the blood vessels.
"We're really starting to marry the fields of neuromodulation, cardiology and cardiovascular medicine," Rezai said in an interview. He also felt the new effort would be far safer.
The Cleveland clinic's experiments cannot have come at a better time, it is felt. For research has indicated that drug-coated stents slightly raises the risk of life-threatening blood clots months or years after they're implanted, unless people stay on an anti-clotting drug.
Because of that risk, a Food and Drug Administration advisory panel in December warned against "off-label" uses cases in which the devices are implanted in higher-risk patients whose heart conditions don't meet criteria the FDA set in approving the stents. Such uses, done at the discretion of individual physicians, had accounted for about 60 percent of drug-coated stent procedures.
In March this year, a study questioned whether stents are more effective than less-costly drug therapy for treating patients who don't face an imminent heart attack risk. Now, many doctors are opting against off-label use until more is known about the risks. Some are choosing bare-metal stents for certain patients, or relying on drugs alone or bypass surgery.
It is in such a backdrop, the Cleveland approach is gaining wider attention.
"Electrodes may prevent the clotting and it may affect the nerves overlying the blood vessels and make it more resistant to clotting," Dr.Rezai said.
"We've already demonstrated in animals that the nerves surrounding the vessels can be affected. Human studies are about two years out," he said, adding that a product could potentially be on the market within five years.
Rezai noted that using electricity to affect nerve function can be applied to treat many diseases.
"Every single organ has input from the nervous system. The more we can understand how the nerves affect the organ function, the more we can use the technology to regulate the nerves."