Angioplasty is a minimally invasive surgical repair of a blood vessel, such as a blocked or narrowed coronary (heart) artery, which aims to improve blood flow. This common procedure involves inserting a thin wire into one of the larger arteries, such as in the arm or groin, to the site requiring repair. When the wire reaches the area of the blockage, a catheter (tube) with a deflated balloon on the end is threaded into the blocked artery under X-ray guidance. A small amount of dye may be injected through the catheter into the bloodstream to help show the blockage on X-ray. (This X-ray picture of the heart is called an angiogram.) When the tube reaches the blockage, the balloon is inflated, forcing the blockage to open by pushing the walls of the artery outwards. Commonly, a stent (artificial tube) may be placed at the site to keep the artery open. Once the balloon has been deflated and withdrawn, the stent remains in place permanently, holding the blood vessel open and restoring blood flow to the arteries and heart muscle.