What will you learn?
- how to conduct incremental pacing
- what this basic manoeuvre tells you about the patient heart
- what is the normal response
About this scenario
- Atrial pacing train followed by an atrial extrastimuli
- The atrial extrastimuli is progressively shortened (10 ms by 10 ms)
- In case of AV conduction through the AV node, the AH interval progressively increases (because of the decremental properties of the AV node), the HV interval remains stable
- An AH jump (>50 ms) between two consecutives sequences (second extrastimuli 10 ms shorter) is suggestive of a conduction through a slow pathway (block through the fast pathway)
- In case of antegrade accessory pathway, the AH interval increases whereas the AV interval remains stable so the HV interval becomes negative
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