A breakthrough has been achieved in the stream of medical science. An alternative to the metallic stent has been found and is called biodegradable or bio-absorbable stents.
Difference between the two
Metallic stents which are in use for a long time now, had some disadvantages. These stents helps to keep the blocked arteries open to enable the flow of oxygen and blood, but also causes retenosis, that is, it scars up vessel tissue causing the arteries to clog again. Even though drug infused metallic stents have also been used as an alternative, it still does not lower the risks of other complications.
Biodegradable stents, on the other hand causes no such complications. It opens up the blocked arteries and dissolves itself after fulfilling its task, thus, minimizing the occurrence of any complication. It is made up of poly-l-lactide, a naturally dissolving material. It is said to dissolve in a time span of 18 months to three years. Another advantage of this stent is that it does not prevent the detection of other blockages as opposed to the metallic stents which would refract the rays of the scan, making it hard for detection.
Benefits of not having a permanent stent
One of the greatest benefits of not having a permanent stent is that it allows the lumen to expand. When a permanent metallic stent is used it does not allow the lumen to grow, thus hindering remodeling even though it allows the vessel around the stent to develop.
Another benefit is they do not produce any kind of inflammatory reactions as opposed to metallic stents.
How does a biodegradable stent work?
Arteries start getting clogged up due to the accumulation of fatty matter like chlorestol on the inner wall of the arteries that are responsible for providing blood to the heart. As it advances, it reduces the width of the lumen in return diminishing the amount of blood flowing into the heart. This is when a person undergoes a chest pain known as angina.
This disease can be arrested at the initial stage with the help of medication. But a person suffers a heart attack when the precautions are not taken, or when the artery is fully obstructed. That is when the surgical procedure of angioplasty is done. In angioplasty, a balloon is introduced into the artery through a guide wire and is inflated where the blockage is located. After this the stent is introduced so that it keeps the artery open.
The biodegradable stent releases a drug called everolimus which prevents irregular tissue growth.
Researches and studies that classify biodegradable as safe
Kunhiko Kosuga, who has a MD, PhD and is also the director of cardiology at Shiga Medical Center for Adults in Moriyana City, Japan, did a research on these new stents. He and his fellow researchers studied 44 men and 6 women who had undergone angioplasty and had used biodegradable stents to open up the affected arteries. They looked for various complications like clots, deaths, and other causes. The result is as follows:
? for the deaths associated with heart diseases, the survival rate was 98%.
? for death from all causes, the survival rate was 87%.
? there was no main cardiac problems in half the patients.
? Only four patients suffered heart attacks.
? The blood vessel involved had re-narrowed in 16% of the patients, in one year after undergoing the procedure.
? there were two clots that were found within the stent. One was due to the drug-infused stent close to the biodegradable one.
Countries who welcomed biodegradable stents
Nine European countries, Middle East, parts of Latin America and parts of Asia like India, Hong Kong, Philippines and Vietnam are already using these stents. In Europe, Asia-Pacific, Canada and Latin America, over 600 patients have taken part in the trial which aspires to have 1000 patients from over 100 centres present in these counties. Even Singapore has approved of these stents from 20th December, 2012.
However, doctors are still awaiting results for the long term effects on the patients
Even though the cost for manufacturing these stents is very expensive, doctors worldwide are optimistic that they will replace metallic stents eventually.
About The Author: Alia is a writer/blogger by profession. She loves writing, travelling and reading books. She contributes to Hydroxycut
Source:
http://www.biotechblog.org/entry/biodegradable-heart-stents-safe/
