Stent is a cylindrical mesh knitted using very fine metallic wires, inserted into a vessel wall to reduce possibility of re-narrowing of a vessel which has been opened by balloon procedure.
This fine tube is guided through groin artery. By monitoring on the screen, it is ensured that deflated balloon on its tip and deflated stent on it is placed inside the stenosis in the vessel.
The largest difference between stents in terms of reducing the possibility of re-narrowing of the dilation created is whether it is covered by a medication or not.
Normal stents (without medication) are partially helpful against such re-narrowing. In the case of stents with medication, special medications prevent cells from multiplying on vessel wall and re-narrowing it. This release is definitely not permanent. However, release of the medication during initial stages when re-narrowing occurs most frequently proves to be adequate.