my heart skips

  I am a 23 year old woman that has been experiencing a slow increase in "skips". They used to occur only when I would reach down to pick up something. My heart would slow down or skip. In the past week my heart has skipped at least once a day. It is a frightening experience, and it feels like I'm getting a quick shock.
  In the past year I have experienced an increased amount of stress, that I am sure has had an effect on my body. I only drink one cup of coffee a day.
  My last EKG 6 months ago came back OK, but I was diagnosed at the age of 16 with an irregular heartbeat due to bulimia and a potassium deficiency. I am otherwise a healthy, happy person that wants this to go away. I am average weight, do not smoke, and eat healthy. Please give me an idea of what could be causing this,
  and how I can kick it.
  Thank you,
  Brooke
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Dear Brooke:
Extra heart beats are a common problem.  They can cause a lot of aggravation, but rarely signify serious heart disease.  Metabolic problems (like a low potassium level) or thyroid problems can cause trouble with the heart rate.  Problems with the heart itself, such as leaky or tight heart valves, can sometimes predispose to extra heart beats.  A thorough medical history and exam, as well as basic blood work, can usually screen for any important medical problem that may be causing the extra heart beats.  An EKG, with careful interpretation, is important.  A holter monitor [sort of a portable EKG machine that is worn like a Walkman radio] can be used to document what the irregular heart beats are and is a useful diagnostic tool.  Occasionally, a cardiac ultrasound [echocardiogram] will be indicated to look at the heart structure.
Most of the time, no underlying cause can be found.  If the extra heart beats are terribly annoying, medications can be used to decrease their frequency.  This is really a measure of last resort, since medicines can have side effects that are more serious than the problem being treated.
You should eliminate caffeine from your diet.  This includes any coffee, tea, chocolate, and many soft drinks.  Diet pills can also cause extra heart beats.  Alcohol and illegal drugs can cause extra heart beats.  Stress can trigger extra heart beats.  Avoidance of all these factors is a good start that helps many people, though not everyone with extra heart beats.  I hope this advice is useful.
If you wish to be evaluated here at the Cleveland Clinic, please call 1-800-CCF-CARE for an appointment with a cardiologist who specializes in heart rate problems at desk F15.  Information provided in the Heart Forum is for general purposes only.  Specific diagnoses and therapies can only be provided by your doctor.