Can you have a heart attack in your sleep? © Getty Images

Can you have a heart attack in your sleep?

Bad dreams and nightmares can wake you up with a start, but could that be because of your heart?

Asked by: Clive Daniel, by email

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A 2012 study at Case Western Reserve University in Cleveland identified a protein called KLF15 that is involved in regulating the electrical impulses that synchronise your heartbeat. The lowest levels of this protein in the blood occur between 6am and 10am, and this is the most common time of day for the kind of sudden heart attack caused by heart arrhythmia. This is also the time of day when you are most likely to be having vivid dreams, but it’s more likely that the stress of the heart attack would give you the nightmare rather than the other way around.


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