Anxiety May Trigger a Racing Heart

Q. I regularly have heart palpitations the week before menstruating, especially when I'm anxious or going to sleep. My heart tests are normal. Where are the palpitations coming from? Can you put my mind at ease?
-- Renee, Athens, GA

A. This should quiet your mind if not your heart: Palpitations are rarely serious. Having them before your period (or any time there are big hormonal shifts, such as during pregnancy and menopause) is fairly common.

Since your heart’s gotten a clean bill of health, it's time to check other body parts. Let's start with your brain: When you’re anxious, your brain churns out chemicals that ramp up your adrenaline, which makes your heart speed up and go flippity-flop. You could have an anxiety disorder and be having mild flippity-flops all day, but you're too busy to notice them until you lie down to sleep.

Your thyroid could be to blame, too. Too little or too much thyroid hormone can make your heart do a tap dance worthy of the Rockettes.

If your doc says you're in good health, try meditating away the palpitations or just ignoring them -- unless your heart rate jumps to more than 100 beats a minute. If you don't have a fever and haven't just been mugged, call 911 pronto. Ditto if you also have chest pain, dizziness, shortness of breath or start sweating heavily.