Angioplasty Info and the Stent, Part 2
(reconstruction of blood vessels damaged by disease or injury usually performed by inflating a balloon inside the blood vessel lumen (tube) in order to reconstitute the flow of blood)
The Angioplasty Gets Support from the Stent
- Balloon angioplasty of the cardio-coronary artery, or percutaneous transluminal coronary angioplasty (PTCA), is said to be a relatively new procedure introduced in the late 1970's. PTCA = [percutaneous, performed through the skin], [transluminal, passing across a lumen or a blood vessel], [coronary, usually, arteries that supply the heart muscle], [angioplasty, surgical repair of a damaged blood vessel].
- PTCA is a non-surgical procedure that relieves narrowing and obstruction of the arteries to the muscle of the heart (coronary arteries). This allows more blood and oxygen to be delivered to the heart muscle.
- PTCA is accomplished with a small balloon catheter inserted into an artery in the groin or arm, and advanced to the narrowing in the coronary artery.
- The balloon is then inflated to enlarge the narrowing in the artery.
- When successful, PTCA can relieve chest pain of angina, improve the prognosis of patients with unstable angina, and minimize or stop a heart attack without having the patient undergo open heart coronary artery bypass graft (CABG) surgery.
The stent is a tube designed to be inserted into a vessel or passageway to keep it open
- In addition to the use of simple balloon angioplasty, the availability of stainless steel stents, in a wire-mesh design, have expanded the spectrum of patients suitable for PTCA, as well as enhanced the safety and long-term results of the procedure.
- Various "atherectomy" (plaque removal) devices are also available as adjuncts to PTCA.
- These include the use of the excimer laser for photoablation of plaque, rotational atherectomy (use of a high-speed diamond-encrusted drill) for mechanical ablation of plaque, and directional atherectomy for cutting and removal of plaque.
- Arteries that supply blood and oxygen to the heart muscles are called coronary arteries.
- Coronary artery disease (CAD) occurs when cholesterol plaque (a hard, thick substance consisting of varying amounts of cholesterol, calcium, muscle cells, and connective tissue, which accumulates locally in the artery walls) builds up in the walls of these arteries, a process called arteriosclerosis.
- Over time, arteriosclerosis causes significant narrowing of one or more coronary arteries.
- When coronary arteries narrow more than 50 to 70%, the blood supply beyond the plaque becomes inadequate to meet the increased oxygen demand during exercise.
- Lack of oxygen (ischemia) in the heart muscle causes chest pain (angina) in most patients; however, some 25% of patients experience no chest pain at all despite documented ischemia, or may only develop episodic shortness of breath instead of chest pain.
- These patients have silent angina and have the same risk of heart attack as those with angina. When arteries are narrowed in excess of 90-99%, patients often have angina at rest (unstable angina).
- When a blood clot (thrombus) forms on the plaque, the artery may become completely blocked, causing death of a part of the heart muscles (heart attack, or myocardial infarction).
- The arteriosclerotic process can be accelerated by smoking, high blood pressure, elevated cholesterol and diabetes.
- Patients are also at higher risk for arteriosclerosis if they are older (greater than 45 years for men and 55 years for women) or if they have a positive family history of coronary heart disease.
- Coated stent is also known as a medicated stent.
- A tiny cage coated with a drug to prop open an artery and prevent it from closing again.
- The stent is a minute metal mesh tube.
- It is inserted into a coronary artery usually just after an angioplasty has been done to open the vessel.
- The stent slowly releases the drug with which it is coated.
- The drug may, for example, be sirolimus.
- Coated stents reduce the risk of artery re-narrowing, or restenosis, after angioplasty which occurs about a third of the time when bare metal stents are used; however, a coated stent is appreciably more costly than an uncoated one ($3,200 versus $1,000, in 2003).
Definition of Coated stent
There is more information about angioplasty; as well as, the stent at the following links:
Angioplasty Info and the Stent, Part 1
Angioplasty Info and the Stent, Part 3
Angioplasty Info and the Stent, Part 4
Angioplasty Info and the Stent, Part 5
Angioplasty Info and the Stent, Part 6
Angioplasty Info and the Stent, Part 7