If the function of your heart is very poor, you may be at risk for
developing a blood clot, called a thrombus, inside your heart. Blood clots in
the heart are a risk factor for the type of stroke that is caused by a small
piece of the clot breaking off and traveling to the brain. In certain
circumstances, you may need to take a blood thinner (such as warfarin) to prevent a
blood clot from forming in your heart. If you have
heart failure, most doctors would agree that you
should take warfarin if you:
- Have atrial fibrillation, an irregular heart rhythm
which significantly increases the risk of forming a blood clot in your heart
that can travel to the brain and cause a stroke.
- Have an aneurysm of
your heart. This refers to a portion of the heart wall that bulges out and does
not contract when the rest of the heart contracts.
- Have had a previous
stroke caused by a blood clot from your heart.
- Have an existing blood clot in your
heart.
Many doctors also prescribe warfarin when the percentage of blood
pumped out of the heart with each beat (ejection fraction) is very low, because
the lower the ejection fraction, the higher your risk of forming a blood clot
and having a stroke. However, doctors do not agree on how low the ejection
fraction needs to be to warrant warfarin therapy, and some doctors do not
prescribe warfarin based on the ejection fraction alone.
The major risk of taking warfarin is that it also can cause bleeding.
You are at risk for severe bleeding from warfarin if, for example, you have an
active stomach ulcer.
