Commentary: A Supraventricular Tachycardia: What Is It? Where Should One Ablate?

Figures

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  Figure 2:. The occurrence of AV block during AVNRT without any recording of the activation of the His-bundle can be explained by proximal intra-Hisian block.

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  Figure 3:. Slow/fast AVNRT with 2:1 block distal to the most proximal His-bundle potential, recorded in a 19-year-old woman with a 1-year history of episodes of supraventricular tachycardia. (a) During the blocked complexes, the two most distal His-bundle electrograms record a tiny, far-field His-bundle potential. This potential may be easily overlooked to suggest that block occurred proximal to the H potential. (b) Repositioning the His-bundle catheter allowed for clear recording of the proximal H potential during the blocked complexes.