Catheter based intervention is a means of opening blocked arteries that surround the heart muscle. Initially this procedure was performed with a balloon and referred to as Percutaneous Transluminal Coronary Angioplasty (PTCA). Since the inception of that procedure in the late 1970s other means of opening up arteries have developed to include atherectomy which is the removal of fatty material from inside the coronary arteries by either scrapping which is referred to as directional coronary atherectomy, ablation with a high speed drill which is referred to as rotational atherectomy and extraction of the material with cutting which is referred to as TEC-atherectomy. There has also been the evolution of scaffolding devices referred to as stents. These are another means of opening up blocked coronary arteries. Each one of these procedures will be described in more detail in the following paragraphs.