A tiny plastic tube (guiding catheter) is passed through the groin or hand till the origin of coronary arteries, and then a thin soft wire (guide wire) is passed through this tube and is negotiated across the block. Then another tube having a balloon at one end is passed over this wire up to the site of blockage. At this point the balloon is inflated to widen the artery by pushing the plaque against the wall of the artery thereby restoring the blood flow. Now-a-days after dilating with the balloon, a stent is deployed to keep the artery open.
A stent is a tiny metallic mesh tube looking like a spring. We have two types of stents i.e. drug eluting and bare metal. The advantage of the drug eluting stent is that they have been able to achieve a very low reblockage rate of about 0-5% which used to be about 25-30% with bare metal stents.
The stent remains in the body throughout life. The only problem is development of reblockage at the same place where the stent is deployed and this can be minimized by the use of drug eluting stents. Stents cannot be removed after deployment. After 1 to 3 months the endothelial layer forms over the stent and then they become a part of our body.