Doctors and many others have known that heart attacks cause bleeding inside the muscle's of the heart, and now have a way of determining the extent of damage caused in individual cases.
MRI technology has given us the first images of hearts bleeding following attacks, and has allowed doctors to determine that the amount of bleeding most likely correlates to the amount of damage. The images were possible thanks to the magnetic iron content in blood.
When a heart attack happens, blood and oxygen flow to the heart is extremely or completely limited due to blocked arteries, but excess bleeding into the muscle can occur after the arteries are clear again.
Scientists have not done much study on the significance of after-attack bleeding until the MRI images were released. Hopefully the discovery will be used in the future to determine severity of individual heart attacks, more accurate survival rates, and will allow doctors to provide better after care tailored to each case.
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