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  #1  
Old 01-15-2011
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EKG ST changes in MI

Why is there ST elevation in transmural MI
and ST depression in subendocardial

plz explain?
thanks.
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  #2  
Old 01-15-2011
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Default

Read this thread
Origin of QRS complex on ECG!
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  #3  
Old 01-15-2011
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Question ....?

Thanks but my querry was about
ST elevation and depression, can u specify this with respect to trasmural and subendocardial MI
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  #4  
Old 01-15-2011
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Arrow Taking it further

When understand the origin of the QRS as in the link I referred to you in my previous post we can understand why there's ST segment changes in MI.

When you have transmural infarction it will act like a window, so the EKG electrodes will look directly at the septal depolarization without the offset from the ventricular wall depolarization and that's why you have elevation.

In the case of the subendocardial infarction you don't have the positive deflection that originates from the inner layer of the myocardium and therefore you'll see depression.
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Cardiovascular-, Physiology-

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