The High-Tech Heart: Angioplasty with Stents
Very often, surgeons can perform what’s called an angioplasty to clear
blocked arteries. During angioplasty, a tiny balloon is inserted and inflated
inside the blocked artery, compressing the blockage against the walls of the
artery and opening the area to blood flow. This procedure does not completely
clear arteries, but about 90% of angioplasties provide immediate relief from
discomfort and further damage to the heart.
Angioplasty is often not a permanent fix. The arteries can become re-blocked
later, a process known as restenosis. Restenosis may occur because of new
material causing blockage, clot formation, or thickening of the artery wall
caused by stretching it out during the procedure.
How stents can help
A stent is a small mesh tube that is inserted into the artery to keep it
from collapsing. It may be used during a first angioplasty to lower the risk for
restenosis, or during a second angioplasty after restenosis has occurred. It may
also help reduce the risk for heart attack. A stent is somewhat more difficult
to insert than the tiny balloon, because it is larger and less flexible.
However, there is about a 20% lower rate of restenosis when stents are used.
In many cases, surgeons use stents that are coated with drugs that help
prevent scar formation. These are called “drug eluting stents.’ These particular
stents seem to be particularly beneficial for people with diabetes.
If a stent is inserted, the patient’s hospital stay may be slightly longer.
This is because Food and Drug Administration guidelines require that patients
with a stent receive anti-clotting medication and additional monitoring until
new arterial lining covers the stent. In addition, patients will be put on
aspirin therapy indefinitely to avoid clotting. They should avoid having MRI
scans for the first few months because of the metal in the stents. Additionally,
before any dental, urologic or intestinal procedures, patients should receive
antibiotics to prevent infection in the stent.
American Heart Association; National Heart, Lung, Blood Institution;
Circulation, 3 May 2005.