New Stent Keeps Arteries Unclogged

Coronary artery disease patients may have improved results with new drug releasing stent

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) For patients with heart disease, stents have been a major breakthrough for preventing the narrowing of blood vessels. A new drug-releasing stent helps prevent blocked arteries.

Introduced in the early 1990s, stents are small mesh tubes that keep blood flowing through narrow or weak arteries. Patients who have stents, however, sometimes develop too much tissue growth within the treated portion of the artery. Stents that are coated with medicine (drug-eluting stents) stop excess tissue growth.

A recent study showed that a new drug-eluting stent may reduce the risk of having repeat procedures to reopen clogged arteries.

"Ask a doctor about drug-eluting stents to treat heart disease."

Kyung Woo Park, MD, associate professor of medicine in the Department of Internal Medicine, Cardiovascular Center at Seoul National University Hospital, worked as lead investigator on this study to evaluate the effectiveness and safety of the new-generation everolimus-eluting stent.

Stents are used in a non-surgical procedure to treat patients with heart disease. The stents, which provide a type of scaffolding to support the artery walls, are typically placed during angioplasty. Angioplasty is a procedure where a catheter is inserted into an artery, often through the groin, and guided to the area of blockage. Using a balloon or rotating tip, the catheter clears the clogged part of the blood vessel.

Dr. Park and his associates reviewed data on 12,869 patients who were treated with one of two types of drug-eluting stents. Everolimus-eluting stents were assigned to 6,894 patients and 5,975 patients were to receive sirolimus-eluting stents.

Discovered in a soil sample from Easter Island in 1965, sirolimus (brand name Rapamune) was first found to be a fungus-killing agent. Scientists later realized the anti-inflammatory and anti-growth properties of sirolimus, also known as rapamycin, could help with cancer therapy. The properties in sirolimus that inhibit cell growth in cancer were also found to help stop excess tissue growth in arteries.

Everolimus (trade name Afinitor) is derived from sirolimus and works in a similar way. Everolimus allows for rapid absorption into the arterial wall at the site of vessel injury. This study stated that everolimus stents are now the most widely used stents.

Researchers found no significant differences in the risk of cardiac death or heart attack (myocardial infarction) when comparing the two patient groups.

Investigators did find a significant reduction in the risk of repeat revascularization (unblocking of the artery) in the patients with the everolimus stents compared to those with the sirolimus stents.

Patients with everolimus stents also had a reduced risk of stent thrombosis (ST)—a rare condition in which a blood clot forms on the surface of a stent. The researchers reported that definite ST occurred in 0.28 percent of the everolimus group compared to 0.61 percent in sirolimus group.

Paul A. Tucker, II, MD, Chief of Cardiology at St. David’s South Austin Medical Center and dailyRx Contributing Expert said "While it is common knowledge that drug eluting stents are better than uncoated stents for preventing cardiac events such as heart attack, and death, this study reveals that some drug coated stents are actually better than others in terms of preventing artery re-narrowing and the need for further procedures."

“Future studies and analyses with longer duration of follow-up are needed to confirm our results,” said the authors.

This study was published in the February issue of American Heart Journal. The research was supported by a grant of the Korea Healthcare Technology R&D Project, Ministry of Health and Welfare, Republic of Korea, and a grant from the Innovative Research Institute for Cell Therapy, Seoul National University Hospital, sponsored by the Ministry of Health and Welfare, Republic of Korea.

Reviewed by: 
Review Date: 
February 4, 2013
Last Updated:
February 8, 2013