Stent Shrinkage

I heard a new term related to coronary stents today: "shrinkage." Unlike the manly "shrinkage" of the Seinfeld show, it seems new polymer stents can also suffer from "shrinkage:"

(TheHeart.org) Dr Patrick Serruys (Thoraxcenter, Rotterdam, the Netherlands) presented results of the ABSORB trial during a late-breaking session at the American College of Cardiology 2007 Scientific Sessions today. In the trial, 26 patients received the new stent—which, it is hoped, will completely dissolve after 12 to 18 months—and there was no evidence of stent thrombosis after six months, together with a low rate (3.3%) of ischemia-driven major adverse cardiac events (MACE).

But late loss and restenosis were greater with the bioabsorbable stent than with current drug-eluting stents, and Serruys said the 15% shrinkage seen with the new stent may be to blame for these findings. He is hoping that the modification of the stent design—due to be completed by the end of the summer—will solve this problem. "This may be the beginning of a new era. I'm convinced of it," he commented.

However, chair of the late-breaking press conference, Dr Spencer King (Emory University School of Medicine, Atlanta, GA), was more circumspect: "Our early experience with polymer stents was terrible in experiments in pigs. This trial is in only 30 patients, with short follow-up. However, on the plus side, we didn't see any inflammation. Time will tell."

My guess? Shrinkage has already killed this current generation of bioabsorbable stent, but a second-generation polymer stent is already in the works...

-Wes