If you have clogged coronary arteries that restrict the flow of blood to
your heart, should you have bypass surgery or an angioplasty procedure to
open the blocked vessel?
Sometimes, the answer is neither.
“Not all blockages are life-threatening,” says Patrick
Simpson, M.D., an interventional cardiologist with Pinehurst
Medical Clinic. “When someone has coronary arteries that
are less than 50 percent blocked, we generally don’t fix those.
The heart can do extremely well for a long time until a vessel
is about 75 percent closed.”
If patients have artery blockages
of more than 50 percent but
less than 75 percent and have
symptoms such as chest pain, they
might or might not require surgery
or angioplasty, depending on
whether their symptoms are stable.
“If they only have chest pain
when they are exerting themselves,
and if the pain isn’t increasing in
either frequency or severity, then
we can treat them with medicine,”
says Dr. Simpson. “The findings
of a major study released earlier this year confirmed these
patients can do just as well in the long run on medication as
they would if we put in a stent.”
(A stent is a metal scaffold that, during an angioplasty
procedure, is inserted into an artery to hold it open after
the blockage has been cleared away. The clearing is done
by a balloon that compresses the plaque against the wall
of the artery.)
Patients with moderate blockages who don’t require an
interventional procedure are typically given drugs to lower the
amount of cholesterol in their blood, as well as blood thinners
to reduce the risk of clots. These patients may continue to
have chest pain during physical activity.
“But if the pain goes away quickly when they stop to rest
or when they take nitroglycerin, they can do just fine,” Dr.
Nitroglycerin dilates the veins
throughout the body, allowing
them to hold more blood. This
reduces the volume of blood
returning to the heart, so the heart
becomes a little smaller. It doesn’t
have to work as hard or need as
much oxygen, and with less strain
on the heart, there is less pain.
People who have moderate
coronary artery blockage—between
50 percent and 75 percent—and
whose symptoms become more
frequent or severe may need
more than medication. They often need either balloon/stent
angioplasty or bypass surgery.
Sometimes, even people whose coronary arteries are
more than 75 percent blocked do not need an interventional
procedure if their symptoms are stable and not severe. It often
depends on the location of the blockage, Dr. Simpson says.
“If the blockage is out at the tip of the vessel, it is very
unlikely to kill you,” he says. “But if it’s at the top of the vessel,
near the heart, much more of the heart is at risk and we are
more likely to want to fix that.”
According to the current standards of the American Heart
Association, a physician shouldn’t necessarily fix a blocked
vessel, even if it appears to be severe, as long as the patient
doesn’t have worsening symptoms. The physician can just
watch and wait until the symptoms become unstable.
Patrick Simpson, M.D.
Dr. Simpson says he is generally comfortable with that
approach unless the blocked artery is the one that carries
blood to the front wall of the heart. A severe
blockage in that artery is most likely to cause a fatal
Regardless of what the medical literature says,
most patients with severely blocked arteries want
them fixed, even if their symptoms aren’t getting
worse, Dr. Simpson says.
“If I tell you that you have a 90 percent blockage
in a coronary artery but because your symptoms
aren’t bad I don’t recommend fixing it, you probably
won’t be able to live your life without being
constantly worried about your heart,” he says. “So, going
ahead and fixing it is often a very reasonable thing to do so the
patient can get on with life.”
If a blocked coronary artery needs to be fixed, the options
are balloon/stent angioplasty and bypass surgery. A bypass
involves grafting a section of vessel from another part of the
body onto a coronary artery and literally bypassing the area
“Bypass surgery is a time-tested procedure that is good for
people who have multiple blockages, particularly if they want
to have freedom from other interventional procedures for a
long time,” says John Streitman, M.D., a cardiac surgeon with
Patients who have several blockages in the same artery, as
people with diabetes often do, also tend to be good candidates
for a bypass.
Bypass surgery often is the best choice when the patient
needs some other type of heart surgery such as valve repair or
treatment for atrial fibrillation.
“Probably at least half of the operations we do are more
than routine coronary bypass,” Dr. Streitman says. “One
reason the number of surgeries we do is going up is because
we are doing more valve surgery. The baby boomers are
hitting their sixth decade, which means the segment
of the population that gets coronary artery disease as
well as valvular disease is getting larger.”
Bypass surgery is the only option in cases where,
because of the location or nature of the blockage,
an artery can’t be opened with a balloon and stent.
Likewise, not every blockage can be bypassed.
Surgeons can work on most of the heart, but it is
particularly difficult for them to bypass an artery on
the lower left side.
If the wall of the blocked artery has become
hardened with calcium deposits, a bypass might not be
“It’s like trying to sew into an eggshell,” Dr. Simpson says.
In such cases, balloon/stent angioplasty may be the only
Cardiologists and cardiac surgeons have to consider
many factors and sometimes complex sets of variables
in deciding how best to treat patients with clogged
coronary arteries that are keeping the heart from getting
as much blood as it needs.
“Medical science can tell us what to do for 10,000 people
with a disease, but the trick is taking that knowledge and
applying it to a single patient,” Dr. Simpson says. “Each
individual case requires an individual decision, and it comes
down to what the patient in consultation with their physician
believes is the best treatment for them.”