According to World Health Organization (WHO), Cardiovascular disease (CVD) is the number one cause of death globally. From an estimate, more than 17 million people die each year due to CVD. Of these deaths, 85% are due to heart attack and stroke.
Prevention is Better Than Cure!
Most cardiovascular diseases can be prevented by working on lifestyle changes to reduce the risk factors such as the use of tobacco, harmful use of alcohol, imbalanced diet, obesity, and physical inactivity.
The risk of cardiovascular disease increases with prevailing risk factors like diabetes, hypertension, family history of CVDs, hyperlipidaemia, and excessive stress. These patients need early detection and management using counselling and medicines, as required.
What is Coronary Artery Disease?
The coronary arteries are the blood vessels (arteries) that carry blood to the heart.
Coronary artery disease is the disease in which there occurs narrowing or blockage of the coronary arteries. This is caused by the condition known as Atherosclerosis. Atherosclerosis means the build-up of cholesterol and fatty deposits inside the coronary arteries. This deposition is called “Plaques”. These plaques can obstruct the arteries or damage the arteries, which restricts or stops blood flow to the heart.
In the absence of enough blood, the heart cannot get adequate oxygen and nutrients that are needed for the proper functioning of the heart. This causes chest pain (angina) or even a heart attack.
What are the treatments available for Coronary Artery Disease?
The treatment options for Coronary Artery disease include; reduction in the risk factors, medications, Interventional procedures, Coronary artery bypass graph surgery.
Interventional Procedures are minimally invasive procedures to get rid of plaque build-up in the arteries and prevent blockages. Common procedures are balloon angioplasty (PTCA) and stenting.
What is a Stent?
Stents are tiny metal mesh tubes mounted on the tip of the Balloon catheter, inserted during PTCA (Percutaneous Transluminal Coronary Angioplasty). This procedure is used to widen the blocked artery by inflating a tiny balloon. Stents help prevent the artery from becoming blocked again (restenosis).
What are the different types of Stent?
There are two types of stents currently available in the market and are most preferred by the cardiologist.
- The Bare Metal Stents:These are the stents without any drug coating. They just act as a scaffold to open the coronary artery.
As the artery heals, tissue grows around the stent, holding it in place. However, sometimes an overgrowth of scar tissue in the lining of the artery increases the risk of re-blockage.
- The Drug-Eluting Stents:These are the stents that are coated with the antiproliferative drug, which is eluted from the surface of the stent in a controlled fashion, thus help prevent the growth of scar tissue in the lining of the artery. This prevents the re-narrowing (restenosis) of the artery (i.e., restenosis).
What are Drug-Eluting Stents?
Drug-eluting stents in current clinical use after clinical trials showed they were statistically superior to bare-metal stents for the treatment of native coronary artery narrowing, having lower rates of major adverse cardiac events (usually defined as a composite clinical endpoint of death, myocardial infarction, repeat intervention because of restenosis). The first drug-eluting stents to be approved in Europe and the U.S. were coated with mTOR inhibitors, such as Sirolimus.
Drug eluting stents are coated with drugs of limus family like Sirolimus, Everolimus, Zotarolimus. They are also coated by the Paclitaxel drug.
Sirolimus-eluting coronary stent system consists of Sirolimus drug and biodegradable polymer coated on the cobalt-chromium stent platform. The cobalt-chromium platform of this device offers very thin strut thickness and decent radiopacity during the PTCA (Percutaneous transluminal coronary angioplasty). The stent has a semi-closed cell design and features great flexibility, crossability, and conformability. The coating process allows the integrity of coated polymer after excessive stent expansion and a systemic elution of Sirolimus in a well-controlled fashion after the stent implantation.
Drug-Eluting Coronary Stent is mounted on a folded balloon attached to a catheter delivery system for placement into a coronary artery (blood vessel supplying blood to the heart).
The drug content on the stent is a constant quantity of drug per unit area of the stent; as the stent length varies, the total drug loading on each stent varies.
Drug-Eluting Coronary Stent System consists of the following components:
1.Metal alloy Stent
4.PTCA Balloon Delivery Catheter
How do the Drug-Eluting Stent Works?
The drug-eluting stent is mounted on the PTCA balloon catheter tip. This catheter along with the mounted drug-eluting stent is threaded to the blocked coronary artery through a minimally invasive procedure. The position of the stent is checked fluoroscopically. Once in place, the balloon tip, over which the stent is mounted, is expanded, which eventually expands the stent. The stent is implanted in its position, resulting in the opening of the blocked artery. The balloon is deflated and removed. The stent remains in its place. Slowly and in a controlled fashion, the drug is released, which inhibits cell proliferation and thereby reduces the risks of restenosis.
What is the best drug-eluting stent?
The best drug-eluting stent is the one that possesses ideal characteristics of the stent. The physical characteristics of the stent have a great impact on the clinical outcomes. The Choice of metal and strut thickness affects the Restenosis, inflammation, radial strength, radio-opacity. Cell size and design affect Plaque prolapse, side branch access, gaps in drug delivery and stent connectors affect the Flexibility and deliverability, longitudinal strength of the stent.
Kamal’s Drug-eluting stents listed below: are the ones that possess the ideal stent characteristics and provide exceptional clinical outcomes with safety and efficacy.
Drug-eluting coronary stents:
- Stenoflex Sirolimus-Eluting Coronary Stent Syste
- Trackflex Sirolimus-Eluting Coronary Stent System
- EveroShine Everolimus -Eluting Coronary Stent System
- Trackmaster Everolimus-Eluting Coronary Stent System
How long does a drug last in a drug-eluting stent?
The presence of the drug on the drug-eluting stent depends on several factors like stent metal, drug-polymer formulation, the polymer used, stent design, excipient, and the type of drug. However, the drug is completely released from the stent between 30-90 days.
The drug-eluting coronary stent system has proven track records with hundreds of clinical trials for its safety and efficacy. They are safe for human use. When people are dying from heart attacks, a drug-eluting stent is hope and the saviour of your heartbeats.