Coronary Angioplasty

Coronary Angioplasty

Angioplasty is a method to remove blocks from important blood vessels. The most common form of angioplasty is coronary angioplasty, the method of removing blocks from the blood vessels supplying oxygenated blood to the heart known as coronary arteries. Coronary angioplasty was originally described by Andreas Gruentzig in 1975. He used a balloon at the tip of tiny long tubes known catheters to dilate narrowed coronary arteries. The procedure is also known as PTCA, Percutaneous Transluminal Coronary Angioplasty.

Blood vessels supplying the brain, kidneys and the limbs can also be treated by angioplasty. Coronary angioplasty is usually done when one or more blood vessels supplying the heart are critically narrowed, more than 70% decrease in diameter. The most important benefit of angioplasty is symptomatic relief, rather than improvement in survival. The procedure is done under local anaesthesia. The tiny tubes used for angioplasty can be introduced into the body either through the groin or wrist.

Tubes are threaded back into the main artery of the body called aorta and from the aorta into the coronary arteries under x-ray fluroscopic guidance. Initially iodine containing contrast dye is injected into the vessels to visualise the sites of narrowing. Once localised, a floppy guide wire is used to cross the narrowed segment of the vessel. A balloon tipped catheter is threaded over the guide wire across the narrowing in the vessel.

After confirming the position of the balloon by further injections of contrast dye, the balloon is inflated, enlarging the lumen of the vessel. Since the vessel which is newly dilated has a tendency to recoil and close off, it is stented using stainless-steel or cobalt-chromium stents. Stents are tiny metallic structures like springs meant to hold the enlarged vessel lumen in position without closing off.

The cost of stent depends on the type of material used – stainless steel stents being cheaper than cobalt-chromium stents. Drug eluting stents having a polymer coating holding drugs which prevent narrowing of vessels treated by angioplasty. One of the important disadvantages of angioplasty is the higher recurrence rate than bypass surgery, which is the alternative mode of treatment for severe blocks in coronary arteries.

Chance for recurrence increases with the number of blocks treated. Hence some may prefer bypass surgery for those with multiple blocks. The advantage of angioplasty over bypass surgery is the earlier mobility and return to work. While the individual has to be in hospital for at least a week after bypass surgery, it is usually possible to go home in one or two days after an angioplasty.

If the procedure is done through the blood vessels at the wrist, one can start walking within a few hours. Medicines to prevent recurrence of blocks have to be meticulously taken after angioplasty. Otherwise blood can clot within the stents and produce sudden total blocakge and sometimes a major heart attack. A healthy life style with good diet, regular exercise and avoidance of risk factors like smoking are important to prevent new blocks from developing in other locations.