Although drug-eluting stents continue to represent a major medical advance for angioplasty, evidence has always shown new clot thrombosis formation with stents to be a problem, thus clotting suppressant agents are routinely given during placement, and anticlotting agents should be continued; the question is for how long.
A stent is a foreign object in the body, and the body responds to the stent's presence in a variety of ways.