Clinical experience and applications of drug-eluting stents in the noncoronary vasculature, bile duct and esophagus

ObjectiveTo review the use of drug-eluting stents outside the coronary artery.FindingsThe vast majority of research and clinical data on drug-eluting stents are from their use in coronary artery atherosclerosis; however, these devices can be used outside the coronary circulation in both vascular and nonvascular structures. In noncoronary arteries the principle indication for drug-eluting vascular stents is the same as in the coronary circulation, prevention of restenosis. Human experience has been essentially limited to trials or compassionate use; two small controlled studies and a number of small observational single center reports have been published, and there are trials in progress. To date the data have not been as compelling as in the coronary circulation. The physical characteristics of each vascular bed such as external compressive forces, blood flow rates, wall thickness relative to lumen size, and vessel wall composition differ significantly from the coronary circulation and each presents unique challenges to local drug delivery. Outside the vascular bed, the principle expected use is the prevention of tissue ingrowth after stent insertion in tubular structures such as the trachea, esophagus or bile ducts.ConclusionsConsiderable further study of drug-eluting stents will be required in each anatomic region to determine the ideal stent/drug combination and clinical appropriateness.