by Dr. Iain Corness
Stenting - a lifesaving procedure
The advances in cardiac surgery have
been enormous over the past 20 years. We have gone from some fairly
primitive high-risk surgery, to some very, very sophisticated interventional
techniques, which have given cardiac patients a new lease of life. In fact,
if the techniques that are available now, were able to be carried out 30
years ago, my father would in all probability, still be alive today.
However, before getting into modern life-saving techniques, a short review
of cardiac pathology is in order. Myocardial infarction is the common cause
of cardiac muscle death, and finally ours. (Make that “yours” as I’m not
The heart muscle is supplied with oxygenated blood by its own system of
arteries. The heart does not get its oxygen from the blood in its chambers.
Instead, there is a network of ‘heart’ arteries (called the coronary
arteries) which supply the cardiac muscle. If any of these get blocked, this
is known as a “stenosis” or an “occlusion”, which in turn can bring on the
coronary “conclusion”! The death of the muscle is called “infarction”.
The blockage is most often caused by Cholesterol, which gets deposited on
the inside wall of the arteries and is called “plaque”, and then red cells
stick on the surface of the deposit and it builds up from there. If you are
overweight, a diabetic or a smoker, you have an even greater chance of a
blockage. If you have a 50 percent stenosis, you will start to get chest
pains on exercise. If you have a 100 percent stenosis, you may drop dead
during the exercise.
To correct this problem, the only way we knew was to carry out an open heart
operation, replace the blocked coronary arteries with vessels taken from
other parts of the body, usually veins from the leg. However, now we can
leave your arteries where they are, but do something to relieve the
stenosis, or blockage. This is called “Angioplasty”.
One way is to send an inflatable balloon to dilate the blocked area, and
this is known as Coronary balloon angioplasty. It is more formally known as
percutaneous transluminal coronary angioplasty (PTCA): percutaneous meaning
“through the skin,” transluminal meaning “inside the blood vessel,” coronary
meaning “related to the heart,” and angioplasty meaning “blood vessel
Angioplasty involves creating space in the blocked artery by inserting and
inflating a tiny balloon, which compresses some of the blocking plaque
against the arterial wall. When the balloon is deflated and removed, the
plaque still remains compressed, clearing a space in the artery and
improving blood flow. While angioplasty does not always completely clear an
artery, more than 90 percent of all procedures are immediately successful.
There are other techniques available, and the most common is by using
“stents”. This is called percutanous coronary intervention (PCI). The
success in today’s cardiac surgery is due in part to the increased use of
these tiny wire mesh tubes called stents, which cardiologists began using in
the 1990s to help keep arteries open following angioplasty. About 70 to 90
percent of all angioplasty patients receive a stent, which is inserted
permanently at the site of the blockage.
Stents can be used in a number of ways with angioplasty procedures. A stent
may be inserted during an original angioplasty to prevent possible arterial
collapse and lower the chance of heart attack and re-narrowing of the artery
(called re-stenosis). A stent also may be inserted during a second
angioplasty to prevent recurrent restenosis. Stents can also be used in the
unlikely event that an artery is injured by the catheter. Experienced
doctors are able to install stents in one or more arteries with a high
probability of success.
The use of stents has decreased the abrupt and unpredictable closure of an
artery, which necessitated emergency coronary artery bypass surgery. Studies
show stents are better than angioplasty alone in preventing re-stenosis,
which is one of the most common problems associated with angioplasty.
Evidence suggests that angioplasty patients are doing better today because
doctors are better able to target blockages, by using such techniques as an
angiogram, so your interventionist is able to pinpoint the blockage with
greater accuracy. Do not ignore chest pains!