Heart disease angioplasty. Computer artwork showing a normal coronary artery (at top), a coronary artery displaying atherosclerosis (at second from top), which is the narrowing and hardening of the arteries through a build up of fatty plaques, and treatment with an angioplasty (bottom three images). The middle image shows the insertion of a balloon catheter and stent (small mesh tube), which is then expanded (second from bottom, blue arrows) to reopen and strengthen the weakened artery. The balloon is then deflated and removed, leaving behind the stent (bottom image), lined with a drug that prevents the vessel from narrowing again in the future (purple).