Biodegradable Igaki-Tamai Coronary Stent Demonstrates 10-Year Safety

April 16, 2012—The American Heart Association announced that the first fully biodegradable coronary artery stent implanted in humans proved safe in a 10-year study published by Soji Nishio, MD, et al online ahead of print in Circulation.

The biodegradable Igaki-Tamai stent (Kyoto Medical Planning Co., Ltd. Kyoto, Japan; formerly, Igaki Medical Planning Co., Ltd.) received CE Mark approval in November 2007. The device is made of poly-l-lactic acid, a cornstarch-based material, which dissolves into the artery wall. This leaves no permanent foreign material in the artery, reducing the occurrence of an in-stent blood clot.

According to the American Heart Association, the device is used in nine European Union countries and Turkey—but not in the United States—to treat peripheral arterial disease (PAD). However, no countries have approved the Igaki-Tamai stent for treating clogged heart arteries.

In the study, the investigators followed 50 Japanese patients (44 men, average age 61 years old) who received 84 Igaki-Tamai uncoated stents between September 1998 and April 2000. After an average of 10 years of follow-up, the investigators found survival rates of 98% free from cardiac death and 87% free from death from all causes; 50% of patients experienced no major cardiac complication, and there were acceptable major event complication rates that were similar to those for bare metal stents.

“We have needed this long-term clinical data to clarify the coronary safety of the stent,” commented study investigator Kunihiko Kosuga, MD. “Our findings will pave the way for the entry of coronary stents made of biodegradable polymers into the real world of interventional cardiology.”

The investigators expected stent degradation to take 6 months, but the study indicated the stent was totally absorbed in 3 years. “Fully biodegradable stents may hold an important position as the next generation of coronary devices,” concluded Dr. Kosuga.