Drug-eluting coronary artery stents.

Many advances have been made in the percutaneous treatment of coronary artery disease during the past 30 years. Although balloon angioplasty alone is still performed, the use of coronary artery stents is much more common. Approximately 40 percent of patients treated with balloon angioplasty developed restenosis, and this was reduced to roughly 30 percent with the use of bare-metal stents. However, restenosis within the stent can occur and is difficult to treat. Drug-eluting stents were developed to lower the rate of restenosis, which now occurs in less than 10 percent of patients treated with these stents. There have been concerns about abrupt thrombosis within drug-eluting stents occurring late after their implantation, leading to acute myocardial infarction and death. Recent studies have alleviated, but not completely dispelled, these concerns. Strict adherence to dual antiplatelet therapy with aspirin and a thienopyridine is required after stent placement, and the premature discontinuation of therapy is the most important risk factor for acute stent thrombosis. Adequate communication between cardiologists and primary care physicians is essential not only to avoid the premature discontinuation of therapy, but also to identify, before stent placement, those patients in whom prolonged antiplatelet therapy may be ill-advised. Elective surgery following stent placement should be delayed until the recommended course of dual antiplatelet therapy has been completed.