Can You Get a Cramp in Your Heart?

[fluidistic]

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?

 

[Astronuc]

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?

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.

Anyone who has experienced a muscle cramp (charley horse) can attest to the fact that it can be quite painful. Muscle cramps occur when muscles involuntarily contract and cannot relax.

The skeletal muscles (those over which we have voluntary control) are most prone to cramping. The skeletal muscles in the calf, thigh, and arch of the foot are most notorious sites of cramps.

Cramps can be perceived as mild twitches or may be excruciatingly painful. Typically, cramps cause an abrupt, intense pain in the involved muscle.

Often a muscle that is cramping feels harder than normal to the touch or may even show visible signs of twitching. Most cramps resolve spontaneously within a few seconds to minutes.

It is not known exactly why muscle cramps develop. Insufficient stretching before exercise, exercising in the heat, and muscle fatigue may all play a role in their causation. Imbalances in the levels of electrolytes (sodium, potassium, chloride, calcium and phosphate) in the blood can also lead to muscle cramps.

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

Leg pain can be due to a muscle cramp (also called a charley horse). Common causes of cramps include:

Dehydration or low amounts of potassium, sodium, calcium, or magnesium in the blood
Medications such as:
Diuretics, which can cause you to lose too much fluid or minerals
Statins, which lower cholesterol and can cause muscle injury
Muscle fatigue or strain from overuse, too much exercise, or holding a muscle in the same position for a long time

Charley horse
http://www.nlm.nih.gov/medlineplus/ency/article/002066.htm

 

[fluidistic]

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

The skeletal muscles (those over which we have voluntary control) are most prone to cramping. The skeletal muscles in the calf, thigh, and arch of the foot are most notorious sites of cramps.

, 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?

 

[Yanick]

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.