It is an endovascular procedure to widen narrowed or obstructed arteries or veins, typically to treat arterial atherosclerosis. An empty, collapsed balloon, known as a balloon catheter, is passed over a wire into the narrowed locations and then inflated to a fixed size. The balloon forces expansion of the stenosis(narrowing) within the vessel and the surrounding muscular wall, opening up the blood vessel for improved flow, and the balloon is then deflated and withdrawn. A stent may or may not be inserted at the time of ballooning to ensure the vessel remains open.
Angina (chest pain) - A person may experience chest pain, or angina, during exercise or stress because the heart's arteries are too narrow to carry enough blood and oxygen to meet the increased demand. Different types of angina are discussed below. In those suffering angina, who have not responded to standard medical treatments, and continue to have symptoms, angioplasty will be recommended.
Heart attack - During a heart attack, an artery becomes completely blocked, cutting off blood and oxygen to part of the heart and causing that tissue to die. This is why heart attacks cause such severe pain. Reopening the artery right away can minimize the amount of heart tissue that is damaged during a heart attack. But this is not applicable for everyone after a heart attack.
Angioplasty will generally not be offered to people without symptoms (but who may have some blockage in a coronary artery), and angioplasty to a number of coronary arteries ('multilevel angioplasty') is usually not performed in diabetics. 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 catheter, into an artery through a cut in the upper leg or the arm. The catheter is then maneuvered into the clogged artery and a balloon on the tip of the catheter is expanded. The balloon pushes against the plaque in the wall of the artery and flattens it, thus widening the artery.
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 a 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 restenosis).
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 angina. It is used for patients who aren't candidates for angioplasty or bypass surgery, usually because their heart is too weak to withstand either procedure or because plaque build-up is so widespread that it would be impossible to treat every narrowing.
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.