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ekg

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usmletopper2
Forum Senior

Topics: 25
Posts: 119

05/23/08 - 10:53 AM

can any one explain the ekg changes in (do not list them plz try to explain so that it helps in retaining)

digoxin toxicity

hyperkalemia

hypokalemia

wpw syndrome

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hero
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Topics: 41
Posts: 537

05/23/08 - 11:46 AM 1 of 1 forum leaders found this post helpful

digox - atrial tachicardia + AV block

hyperK - peaked T wave --> with progression QRS and T merge to sine wave

hypoK - flat T, ST depr, U wave

wpw - wide QRS with initial deflection - delta wave

mildus
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Topics: 19
Posts: 614

05/23/08 - 01:55 PM 0 of 1 forum leaders found this post helpful

digoxin:

descending ST depression, increased PR interval (since digoxin decreases transmittion in atria), VES (e.g. bigeminia) (since digoxin can increase ventricular excitability)

hyperK:

since K+ disturbs the process of repolarization, peaked T wave is the first sign; as K+ increases further, T is taller and then you have that "M" configuration (the same heights of QRS and T); further increase of K+ leads to losing identity of QRS and T and you see a sinusoid

hypoK:

contrary to hyperK, here you have flat or inverse T wave (note that high K+ = tall T, low K+ = flat or inverse T, so T wave is a "tent under which K+ rests"), there is also U wave (positive wave immediately after T wave), and ST depression

wpw:

the main feature is increased transmittion velocity through AV node, thus you have shortened PR interval, so that P wave is very near to QRS that they even merge into a single wave - wider QRS which begins with so called delta wave

usmletopper2
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Topics: 25
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05/24/08 - 12:14 AM

thank u for that

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genbot
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05/24/08 - 12:31 AM

man WPW never causes increased transmission velocity thru the AV node. And i mean never!
Because WPW has an accessory pathway the time it takes for the impulse to travel from the atria to the ventricles becomes shorter and consequently so does the PR interval. The ventricular depolarization through the accessory pathway then merges with that thru the regular AV node to produce the slurrred wide QRS that u see in WPW.

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Vietnamese
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Topics: 12
Posts: 285

05/24/08 - 12:38 AM

Digoxin toxicity: Any arrythmia

genbot wrote:
man WPW never causes increased transmission velocity thru the AV node. And i mean never!
Because WPW has an accessory pathway the time it takes for the impulse to travel from the atria to the ventricles becomes shorter and consequently so does the PR interval. The ventricular depolarization through the accessory pathway then merges with that thru the regular AV node to produce the slurrred wide QRS that u see in WPW.

Agree.

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genbot
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05/24/08 - 01:14 AM

Yes digoxin can cause just bout any arrhythmia but the most characteristic as mentioned above is an atrial tachycardia with an AV block. Ventricular bigeminy is also fairly characteristic.

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mildus
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05/24/08 - 06:16 AM

I agree with you genbot, but I just wanted to simplify for mnemonics purpose

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