Ask the Experts
What is the Impact of Coronary Stents?
Author: Dr. Robert Dappen
Answer: Heart disease is caused by fatty deposition on the insides of arteries that supply blood flow to the heart muscle. The medical term for this is atherosclerosis and it builds up slowly over an adult’s lifespan. This can lead to choking off the blood supply to the heart, causing symptoms which we call angina pectoris. A heart attack occurs if the artery suddenly occludes with a clot at the site of the blockage. Atherosclerosis has been around from time immemorial; found even in the mummies of Egypt.
In 1977, balloon angioplasty was first performed, which is when a balloon inserted into the blockage in the artery is used to dilate and push the internal obstruction outward, thereby restoring normal blood flow through the vessel. This technique offered an alternative to more invasive and complicated open heart surgery procedures. However, angioplasty resulted in a non-controllable stretching of the vessel, which could lead to abrupt closure and also had significant late scarring of the vessel that resulted in repeat blockage in up to 30-40% of patients. To overcome these problems, stents were developed. These thin, slotted metal tubes, or coils, were mounted onto a balloon-tipped catheter and were placed within the obstruction and expanded to open the vessel and restore blood flow. The early stents reduced the risk of abrupt closure, but were also associated with a high risk of late artery scarring, which could eventually lead to re-occlusion of the vessel. Because stents were irritating and exposed to blood flow within the artery, the body’s response was to try to reject them. This could lead to the complication of clot formation and subsequent occlusion of the vessel. To overcome these problems, scientifically designed stents with a special drug coating have been created to reduce the scarring and healing issues, but special anticoagulation drug combinations are required to prevent rejection and clotting.
Today, in the United States, over 700,000 stent procedures are performed. We can use them to treat symptoms of angina or, in cases of heart attack, we can open up the blocked vessel. Under these conditions, we can improve life, keep the heart strong and make patients live longer. The Dignity Hospitals are on the forefront of research with new stents that absorb over time and leave only an intact and healed vessel. This is our commitment to the community: to be on the cutting edge. We continue to see progress with new techniques and devices, helping us reach out to more patients and improve their lives.