Coronary angiography, described above, is a diagnostic procedure during which the coronary arteries are imaged in order to define their anatomy and identify stenoses, or blockages, within the arteries. Coronary angioplasty, or percutaneous transluminal coronary angioplasty (PTCA), is a therapeutic procedure geared toward treating coronary stenosis or occlusion. During this procedure, the cardiologist advances an angioplasty balloon into the coronary artery and, under x-ray guidance, positions the balloon over the site of the blockage, or stenosis. Inflation of the balloon stretches the artery, compressing the plaque against the artery wall, thereby enlarging the artery channel. While the balloon is inflated, it occludes the artery channel and blood cannot pass. During this time, the patient may experience chest discomfort, until the balloon is deflated. Following angioplasty, the artery channel is enlarged. However, since the artery contains elastic tissue, there is always some degree of "recoil" after the balloon is deflated. Over the ensuing weeks, as the artery heals, the recoil process may continue. In some cases (30-40%), severe recoil can cause "restenosis," or re narrowing of the arterial channel. This is a drawback to angioplasty. Fortunately, a device known as a "stent" has been developed that completely overcomes the recoil phenomenon.

 

Step 1:	Step 2:
Step 3:	Step 4:
A Coronary Angioplasty

Coronary stents are designed to be placed into the coronary arteries that lie on the surface of the heart and supply the heart with oxygen-fresh blood. A stent is mounted on an angioplasty balloon in its collapsed state. The stent/balloon assembly is then advanced into the coronary artery and positioned over the site of the coronary lesion. When the balloon is inflated, the stent becomes fully expanded and apposed against the coronary artery wall, "tacking up" the atherosclerotic lesion and buttressing the artery wall. The balloon is then removed but the stent remains in the coronary artery (forever). As a result of advancing stent design, more patients with more complex disease are candidates for stenting, which reduces the number of coronary artery bypass graft surgeries.

Stenting has been an important advance in balloon angioplasty. Before the introduction of stents, as many as half of all coronary arteries opened with a balloon-tipped catheter narrowed once again after the procedure(restenosis). In 2003, a major advancement in stenting was realized with the introduction of a new generation of stents. These stents, call "drug-eluting" stents, are covered with special drugs that reduced the restenosis rate to its current low level. Today, drug-eluting stents comprise the majority of stents in clinical use for coronary disease.

Following stenting, the patient is treated with aspirin in addition to blood thinner, in order to prevent blood clotting at the site of the stent. It is important for the patient to carefully follow their physician's orders regarding these medications, as well as practice healthy lifestyle behaviors, such as not smoking and lowering cholesterol levels. Stents are not affected by metal detectors or most mechanical equipment.