October 6, 2015

Concealed conduction affecting the AV conduction

An adult with h/o of HTN came in due to mechanical fall. What is your interpretation? 

Image 1



As you can see, there are bigeminal PVC's. QRS complexes 1,3,5,7,9,11 are conducted with prolonged PRI's (0.28 sec). The PRI's of complexes 13 and 14 are shorter (0.16 sec). The P wave after QRS complex # 12 is not conducted.

Image 2



The possible explanation as shown in the ladder diagram is PVC with concealed retrograde conduction. 

Prolonged PRI

The sinus P wave following the interpolated PVC reaches the AV node during it relative refractory period (induced by concealed retrograde conduction of the PVC) and is conducted with prolonged PRI.

Blocked P  wave

The P wave (after complex # 12) reached the AV node during its absolute refractory period (induced by concealed retrograde conduction of the PVC) and failed to conduct.

Interpretation: Sinus rhythm, prolonged PRI and non-conducted P wave due to concealed retrograde conduction of PVC's .

* You can read (samples) compiled ECG's in the "ECG Rhythms Flashcards" in the link. If you have time please leave a comment. Thank you.

Reference:
Fisch C and Knoebel, 2000, Electrocardiography of Clinical Arrhythmias, Futura Publishing Company Inc, NY

#498 

1 comment:

  1. Can you explain why the distance between beat #13 and #14 is so far like that??

    ReplyDelete

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