Prevention of restenosis future directions.

Restenosis remains the major limitation of percutaneous transluminal coronary angioplasty. Restenosis after balloon angioplasty is due to vascular remodeling and neointimal hyperplasia. In spite of encouraging results in animal models, most of the pharmacological trials of prevention of restenosis in humans have produced negative results. This has prompted interest in the potential role of locally delivered drugs and various balloon catheter systems that are now available to achieve local delivery of therapeutic agents at the site of arterial injury. In 1997, implantation of a coronary stent in conjunction with balloon angioplasty is performed in an increasing number of patients. Randomized studies have shown that coronary stenting may reduce the risk of restenosis. In addition, restenosis after coronary stenting is mainly due to neointimal hyperplasia. Restenosis within coronary stents might thus be much more sensitive to therapies designed to inhibit neointimal hyperplasia than restenosis after balloon angioplasty. Thus, the future prevention of restenosis might well be the combination of a mechanical device that produces the widest possible lumen and prevents vessel constriction with a pharmacologic approach to inhibit the proliferative process. (Trends Cardiovasc Med 1997;7:90-94). © 1997, Elsevier Science Inc.