The purpose of angioplasty is to widen the coronary arteries of the heart that have been narrowed or completely blocked by plaque build-up or a blood clot. Specifically which angioplasty technique the cardiologist uses depends on where the narrowing is, how it is shaped, and whether it is made of hard or soft plaque.
The cardiologist can choose from the following options:
These procedures are all variations on the original form of balloon angioplasty. They differ mainly in the type of instruments used.
Balloon angioplasty is performed by passing a thin tube, or
Laser angioplasty is similar to balloon angioplasty, but instead of a balloon-tipped catheter, one with a laser at the tip is used. The laser is guided to the blockage, then used to destroy the plaque, layer by layer, by vaporizing it into gaseous particles.
The laser can be used alone, or in combination with balloon angioplasty. If it is teamed up with balloon angioplasty, with the balloon inserted first to attack the hard plaque. The first laser device (the "excimer laser") for opening coronary arteries won U.S. governmental approval in 1992 but is not used as frequently as other angioplasty procedures.
This procedure is begun similar to angioplasty. But instead of a balloon pressing against the fatty deposits in the walls of the arteries, special instruments are used which cut away the plaque.
This technique is proving very useful in treating blockages that may be too calcified (hardened) or inaccessible for balloon angioplasty. The devices that can be used are:
- Extraction atherectomy - This procedure uses a tiny rotating blade that works in much the same fashion as the cutter on a food processor to whisk away blockages inside the artery wall at a rate of up to 1,200 revolutions per minute.
- Rotational atherectomy - This procedure uses a high-speed, diamond-tipped drill to penetrate fatty deposits and is particularly useful on hard, calcified plaque.
- Directional atherectomy - This procedure uses a device that is a combination of a balloon and a shaving blade. The cutting device, usually located on the side, is run back and forth and shaves the deposits away.
Stents are small, expandable, metal devices inserted by a catheter into a narrowed artery after the angioplasty procedure is complete. Stents are left in place to help keep the artery from closing again (a complication called
- Since the first coronary
stentwas approved in 1993, these devices have gained widespread acceptance.
- Stents are now used in combination with balloon angioplasty an estimated 60% to 70% of the time. Direct coronary stenting, which is done without balloon angioplasty, is also an option, but is not used as frequently.
- Generally, stents have improved the outcome of patients who have angioplasty. On rare occasions, a patient can develop blood clots associated with the use of stents. This occurs more often in people with weak hearts, and after the use of more than one stent, or different types of stents.
Nice To Know:
Drilling channels in the heart: When neither angioplasty or bypass surgery is an option
Laser revascularization, also called transmyocardial revascularization (TMR), is an experimental procedure that is being studied as a way to relieve severe
TMR is sometimes called the "snake heart" procedure, because the surgeon duplicates the design of the reptile heart by using a laser to create open channels in the heart muscle. The goal is to enable the lower chamber of the heart, called the ventricle, to pump blood directly through the newly created channels into the heart muscle, rather than relying on blood vessels to do the job.
This procedure has produced early promising results in relieving chest pain, but no long-term studies have been done. Researchers still have many questions about whether it really benefits patients.