Current status of biodegradable stents.

Coronary angioplasty remains limited by abrupt closure and restenosis. Metallic stents are useful for suboptimal PTCA results or threatened closure and can reduce restenosis in de novo lesions. However, they are permanent devices that are used to treat a short-term problem and have only limited potential for local drug delivery. Several catheters have been designed for specific delivery of drugs or gene products. Unfortunately drug delivery efficiency and long-term retention remain problematic. To overcome these limitations and provide a scaffold for the remodeling vessel as well as a vehicle for sustained local drug delivery, bioabsorbed stents have been proposed as an alternative. This article describes the limitations of the current metallic stents, reviews the initial animal studies of polymeric stents, and proposes the biodegradable stent as a local drug delivery device to prevent restenosis and acute closure post-PTCA.