Although inserting another stent into the narrowed artery will solve the problem in a short time, some of the vessels will again narrow, explains Yoshihiro Morino, M.D., a research fellow at Stanford University Medical Center, Stanford, Calif.
The question of whether to re-stent or not to re-stent is an ongoing debate, so our study was designed to address this issue, he says.
Led by Peter Fitzgerald, M.D., Ph.D., director of the Cardiovascular Core Analysis Laboratory at Stanford, Morino and his colleagues analyzed 70 cases of in-stent restenosis. Of these, 34 patients received radiation in their re-narrowed arteries, while 36 made up the placebo group and had no radiation. The 34 patients who had irradiated lesions were divided into four groups: old stent not re-stented; old/new stent overlap, new stent only and lesions treated without re-stenting.
The researchers analyzed the success of the procedure with volumetric intravascular ultrasound, an imaging technique that allows them to measure the interior dimensions of the artery. The ultrasound examinations were done at the time patients where treated for in-stent restenosis and again six months later. The measurement is called lumen volume index (LVI). Higher LVI means blood flows more easily through the vessel.
In patients treated with radiation, the lumen volume was larger for the re-stented segments than the non-stented. However, at follow-up, researchers found that the lumen volume was similar for the re-stented and the non-restented segments, due to the incre
Contact: Carole Bullock
American Heart Association