This is a treatment for patients with one or more narrowings or blockages of the arteries which give the heart it’s blood supply, the coronary arteries. The start of the procedure is the same as for a coronary angiogram. A tube is placed in the artery in either the wrist or groin, under local anaesthetic. A tube is passed up to the heart and pictures taken by injecting dye into the coronary artery with the problem. A very fine wire is then passed along the artery and across the narrowing. A balloon is then passed along the wire and positioned across the narrowing or blockage. The balloon may have a metal cage, called a stent, crushed down onto the outside. Sometimes, a balloon without a stent is used, to open up the artery first, before a balloon with a stent is used. The stent is left behind in the artery and once it’s there it is pretty much impossible to move, so it’s positioned very carefully! Stents may have a special coating to reduce the risk of repeat narrowing (‘restenosis’)- these are called ‘drug eluting stents’ (DES). Some stents do not have a coating and are called ‘bare metal stents’ (BMS). DES tend to be used in situations where it is known the risk of restenosis is likely to be higher than normal.