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Medical Quick question about cramp/heart

  1. Feb 20, 2010 #1

    fluidistic

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    Is it possible to have a cramp in the heart? It would differ from heart attacks I think, but would also being able to kill. So a simply low level of sodium/potassium/calcium in blood could cause us a cramp in the heart and maybe kill us. I just wonder if it's possible. If not, why?
     
  2. jcsd
  3. Feb 21, 2010 #2

    Astronuc

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    I believe the heart is a different kind of muscle tissue than the skeletal muscles. It is contiuously working to pump blood, whereas other muscles need to rest. It wouldn't do to well to have a heart muscle that periodically stopped or failed - as in the case of a heart attack.

    The heart is an involuntary muscle, whereas the skeletal muscles are voluntary. That's an important distinction.

    Ref: http://www.medicinenet.com/muscle_cramps/article.htm

    Muscle cramps
    http://www.nlm.nih.gov/medlineplus/ency/article/003193.htm


    Leg pain
    http://www.nlm.nih.gov/medlineplus/ency/article/003182.htm
    Charley horse
    http://www.nlm.nih.gov/medlineplus/ency/article/002066.htm
     
  4. Feb 21, 2010 #3

    fluidistic

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    Thanks very much for the reply. So the heart would be a different muscle because it works involuntarily and continuously. Just as some muscles involved for respiration and digestion I'd say.

    About the quote
    , it does not explain why muscles on which we have a voluntary control are more prone to cramps than the others muscles. And this "more prone to cramp" doesn't seem to exclude totally cramps on the other muscles such as the heart.

    If the heart and other muscles are completely discarded as being affected by cramps, is there an illness or way for these muscles to be affected by cramps?
     
  5. Feb 21, 2010 #4
    I am not sure that there is truly a concrete answer for this question but it probably lies in the differing mechanisms of depolarization of skeletal and cardiac muscle. The latter of which has a characteristic "automaticity" to the depolarization. If you google cardiac muscle depolarization you will undoubtedly find more than enough information to make your head spin.

    For what its worth, cardiac muscle does have something akin to cramps/spasms/twitches, except they are called arrhythmias and many of them will lead to death instead of a bit of pain.
     
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