Pharmacological approaches to the prevention of restenosis after coronary angioplasty.

Restenosis in the months following a successful percutaneous transluminal coronary angioplasty (PTCA) remains the main limitation to this technique for myocardial revascularisation. Despite intensive investigation in this area, no pharmacological therapy has yet been found to be useful in preventing restenosis after conventional balloon angioplasty. The occurrence of restenosis, which is now known to be caused by both vessel remodelling and neointimal hyperplasia, might be reduced in the future by a combined mechanical and pharmacological approach. Although systemic administration of 'antirestenosis' drugs has not yet been tested to prevent restenosis after coronary stenting, it is very likely that pharmacological inhibition of neointimal hyperplasia within coronary stents will take advantage of local delivery techniques. In addition to local drug delivery catheters that are available, the stent itself may be coated with polymers and serve as a platform for drug delivery. The continued attractiveness of PTCA, as an alternative to medical treatment or bypass surgery for patients with coronary artery disease, will depend upon our ability to control the restenotic process.