ECG - atrial rate

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DocMiami

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Question is : what is the atrial rate? Apparently this is a complete heart block. Can someone clarify? Thanks :)

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Complete heart block occurs when the AV node stops conduction. Since in your EKG based on the rhythm strip, every P has a QRS than its not complete heart block. Also since there are no dropped beats, its not 2nd degree heart block either.
 
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Complete heart block occurs when the AV node stops conduction. Since in your EKG based on the rhythm strip, every P has a QRS than its not complete heart block. Also since there are no dropped beats, its not 2nd degree heart block either.
I would argue it is still fertile ground for a Wenckebach due to the progressive lengthening of the PR. The missed beat may not be on the EKG tracing yet.

Edit: this actually is complete heart block. Missing P waves indicate atrial fibrillation, not heart block. Heart block has P wave intervals (every 7 blocks-- don't remember the exact rate.. <50) whereas the QRS is every 7.5.
 
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You can see clear AV dissociation, it's heart block. Atrial rate is around 100, ventricular rate around 40 or something. Take a piece of paper of calibers and mark out p waves, and if they happen to fall on a QRS or a T wave, then they are buried and the T wave should look different then the rest. If it's hard to see in the rhythm strip, scan the rest of the leads for clear p waves.
 
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This is complete heart block. There is complete AV dissociation such that the QRS complexes are unlikely to be caused by the P waves. Note that the PR changes markedly. Note that the RR intervals are fixed (which belies wenckebac) There are basically 2 P waves for every QRS. There are P waves that are hidden within the T wave and move its way back toward the QRS as you move down the EKG.

There are 14 P waves (multiply by 6 and that gives you an atrial rate of 84)
 
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