An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government
organization in the United States.
Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to
the .gov website. Share sensitive information only on official,
secure websites.
... the heartbeat is too fast (tachycardia) or rapidly switches from being too fast to being too slow ( ... ages, the location of pain changes. Pain attacks switch from affecting the lower body to affecting the ...