Early reports of thrombosis after insertion of drug-eluting stent

Authors of a research letter in this week’s issue of THE LANCET highlight how the use of drug-eluting stents (DES) may carry a risk of subsequent thrombosis if stenting is accompanied by a withdrawal of antiplatelet therapy.

More than 1.5 million people a year have stents implanted to improve coronary artery blood flow. A recently published pooled analysis of 11 trials (see Lancet 2004; 364: 583-91) suggested that DES—increasingly used in coronary angioplasty—have benefits over bare-metal stents (BMS) by reducing the need for later revascularisation and reducing the risk of cardiac events.

Patrick W Serruys (Erasmus Medical Center, Netherlands) and colleagues report four cases of angiographically-confirmed stent thrombosis that occurred around a year after elective implantation of polymer-based paxlitaxel-eluting or sirolimus-eluting stents; all four cases resulted in myocardial infarction (heart attack). All cases arose soon after antiplatelet therapy was interrupted.

Professor Serruys comments: “We report these cases to draw attention to a problem, with serious clinical implications, that might be under-reported. We suggest that the potential risk of stent occlusion should be considered when discontinuation of antiplatelet therapy is contemplated in patients with drug-eluting stents. As the use of drug-eluting stents becomes widespread, careful long-term follow-up of patients with such stents is needed to assess the true rate of late thrombosis.”

In an accompanying commentary (p 1466), Mark J Eisenberg (Jewish General Hospital/McGill University, Montreal, Canada) concludes: “…drug-eluting stents are so new that many health-care professionals are not aware of the critical need for prolonged and continuous antiplatelet therapy. Therefore, both patients and physicians should be sensitised to the possibility of late stent-thrombosis if antiplatelet therapy is interrupted. The case reports by McFadden and colleagues strongly and persuasively suggest that stent thrombosis might occur many months after the implantation of a drug-eluting stent if prolonged and continuous antiplatelet therapy is not maintained.”