Tanguay J F, Zidar J P, Phillips H R, Stack R S
Interventional Cardiovascular Program, Duke University Medical Center, Durham, North Carolina.
Cardiol Clin. 1994 Nov;12(4):699-713.
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.
冠状动脉血管成形术仍然受到急性血管闭塞和再狭窄的限制。金属支架对于不理想的经皮冠状动脉腔内血管成形术（PTCA）结果或有血管闭塞风险的情况很有用，并且可以减少原发性病变中的再狭窄。然而，它们是用于治疗短期问题的永久性装置，并且在局部药物递送方面潜力有限。已经设计了几种导管用于特定药物或基因产物的递送。不幸的是，药物递送效率和长期保留仍然存在问题。为了克服这些限制并为重塑血管提供支架以及持续局部药物递送的载体，生物可吸收支架已被提议作为一种替代方案。本文描述了当前金属支架的局限性，回顾了聚合物支架的初步动物研究，并提出可生物降解支架作为预防PTCA后再狭窄和急性血管闭塞的局部药物递送装置。
