Cause
Coronary artery
disease is caused by the buildup of
plaque on the inside of your
coronary
arteries
. In most people, plaque buildup begins early in life and
gradually develops over a lifetime.1
Coronary artery disease typically begins when the inside walls of the
coronary arteries are damaged because of another health problem, such as:
Plaque, which is made up of excess cholesterol, calcium,
and other substances in your blood, builds up on the damaged inner walls of
your coronary arteries. This process usually occurs throughout the body and is
called
atherosclerosis, or "hardening of the arteries." See
pictures of
atherosclerosis
and
how high
blood pressure damages arteries
.
Over time, plaque buildup
narrows the coronary arteries and can lead to
ischemia (insufficient blood flow to the heart
muscle). Ischemia (say "is-KEE-mee-uh") can weaken the heart muscle, but it
usually does not cause heart muscle cells to die.
But heart
muscle cells can die if blood flow is severely reduced or completely blocked
for a period of time. This can happen if plaque breaks apart and makes a clot
that blocks an artery. This can cause myocardial infarction, or
heart attack.