By Ace Heart & Vascular Institute, Cardiology
What is a Heart Stent?
Heart stents are used to treat blockages in the coronary arteries that supply the heart with blood. A total blockage in a coronary artery would lead to a heart attack, and if not treated rapidly can lead to death of heart muscle. A significant blockage of an artery, usually greater than 70%, can lead to symptoms such as chest pain, shortness of breath and heart muscle damage. Heart stents can be used to treat these heart blockages and open up the artery, relieving the blockage and restoring normal blood supply.
A heart stent is basically a small metal tube that is expanded inside the area of blockage. Once expanded it remains there and acts as a scaffold to keep the artery open. In the earlier days we used balloons to try and open the artery, but after the balloon was deflated the blockage would often recoil, meaning the chance of a successful procedure was not always good. With the development of heart stents, however, the scaffold from the stent prevented the recoil and meant the artery stayed open.
Problems with Traditional Heart Stents
Although the development of heart stents was a major breakthrough, the presence of these scaffolds within arteries was not entirely without problem. It’s important to remember that vessels are reactive in nature. They expand and constrict in response to various stimuli. This is prevented by metallic heart stents. Vessels themselves are always undergoing changes and the presence of heart stents can disrupt this process known as remodeling. Metallic heart stents often mean that patients are required to take lifelong blood thinning medication.
These are just some of the problems associated with heart stents, and therefore it was very exciting when absorbable stents were developed. The Bioresorbable Scaffold Revascularization is when the scaffold is initially placed and restores blood flow in the vessel. In the restoration phase the scaffold begins to degrade and the vessel regains some of its natural properties. In the reabsorption phase, the scaffold completely disappears leaving a natural vessel behind.
Who are the patients eligible for BVS?
- Single Vessel Coronary Artery Disease
- Diameter stenosis >50% specially in LAD artery
- Premature Coronary Atherosclerosis
The use of scaffold should preferably be avoided in complex/bifurcation/left Main artery interventions. Aorto-ostial and Thrombus containing lesions should also not be tackled with this technology.