Biodegradable Stents Safe Long Term

Biodegradable coronary artery stents safe over 10 year period

(RxWiki News) A lengthy study has found that experimental biodegradable coronary artery stents, designed to prop open clogged coronary arteries to increase blood flow, are safe long term.

The biodegradable Igaki-Tamai stent was found safe over a 10-year period. The stent already is approved to treat peripheral artery disease in Turkey and nine European countries, but not in the U.S. It has not yet been approved for treating coronary arteries.

"Discuss benefits of various stents with your cardiologist."

Dr. Kunihiko Kosuga, co-author of the study and director of cardiology at Shiga Medical Center for Adults in Japan, said that the long-term data was needed to clarify safety when used in coronary arteries. He said the findings could pave the way for coronary stents constructed of biodegradable polymers.

Traditional bare metal stents, some of which are coated with medication, remain in the body permanently. The biodegradable stent is made of poly-l-lactic acid, a cornstarch-based material, capable of dissolving into the artery wall. Research has suggested it could reduce in-stent blood clots because it leaves no foreign material in the body.

During the study investigators followed 50 Japanese patients who received 84 Igaki-Tamai stents between September 1998 and April 2000. Most were men and the average patient age was 61. They were followed for 10 years.

A decade after the study began investigators found that 13 percent of patients had died from any cause, but only 2 percent of deaths were cardiac-related. About 50 percent of patients did not experience major heart complications, considered an acceptable complication rate since it is similar to the amount among patients with bare metal stents.

Upon beginning the study, researchers had anticipated the stents would dissolve within six months, however, the study revealed they were not completely absorbed for three years.

“Fully biodegradable stents may hold an important position as the next generation of coronary devices,” Dr. Kosuga noted.

The findings were recently published in Circulation, an American Heart Association journal.

Review Date: 
April 12, 2012