CORONARY STENTS

Coronary angioplasty also called percutaneous coronary intervention is a procedure used to open clogged heart arteries. Angioplasty involves temporarily inserting and inflating a tiny balloon where your artery is clogged to help widen the artery.It is often combined with the permanent placement of a small wire mesh tube called a stent to help prop the artery open and decrease its chance of narrowing again.Doctors have been using stents to clear blocked arteries for the past 20 year.

Different types of Coronary Stents

There are three major types of coronary artery stents: 

#1.Bare metal stents (BMS)
#2.Drug-eluting stents (DES)
#3.Bioresorbable Vascular Scaffold stents (BVS).

BMS-The bare metal stent has mesh qualities and does not have medication attached in or outside of the stent. This stent represents the first generation of stents.The mesh stent has proven itself, as many people have received this type of stent and live normal lives without chest pain. Once the surgeon installs this type of stent, the person will need to take anti-coagulants and blood thinners such as aspirin.

DES-The drug-eluting stent works by including medication within the stent. This makes it a step up from the usual plain mesh metal stent. This medication keeps the stent from becoming blocked after a period of time.The person with the drug-eluting stent needs to change the lifestyle and follow a strict medical regime in order for the stent to have the desired effect.

BVS- This Bioresorbable Vascular Scaffold stent is made up of polylactide- a bio- compatible material that is generally used in dissolving sutures.This is a stent that dissolves after it finishes doing its job.It starts dissolving in the body after about 12 months and it takes anywhere between two and three years for it to completely dissolve.While these dissolvable stents are placed in the same location as a traditional stent, it takes slightly longer to insert a dissolvable stent, because the device is less flexible. 

What Stents To Use?

Stents cannot be used in all the cases of angioplasty because they are difficult to mould across tight bends in blood arteries that are badly clogged with plaque. The decision on which type of stent to use should depend on the persons symptoms, and on the size and shape of the narrowed part of the artery.

*DES were introduced in response to the high observed incidence of late stent re-stenosis with BMS. Re-stenosis is a side-effect of the normal healing process with the growth of scar tissue around the stent mesh in a process called neointimal hyperplasia, which in some cases, can lead to occlusion of the coronary lumen. The process peaks at around the third month and reaches a plateau at between 3 and 6 months after the procedure.

A drug-eluting stent should be used if the person has angina, and the inside diameter of the artery is less than 3 mm across, or the narrowed area is more than 15 mm long. There are several different drug-eluting stents, which contain different drugs.If more than one artery is narrowed, doctors should make the decision on which type of stent to use for each artery separately.

*The BVS dissoving stent has an advantage of " No metal left behind" which means a lower risk of clotting and stent fractures.

With the advancement in technology and research, the quality of the stents is improving and its cost is decreasing steadily.