Utility of dual‐chamber Electrogram‐based pace mapping in a teenager with a focal atrial tachycardia, low inducibility, and indeterminate earliest excitation site

Figures

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  FIGURE 1. This 12‐lead electrocardiogram exhibits a long RP' narrow QRS tachycardia. The P′ wave was negative in the inferior leads and exhibited a saw‐tooth morphology. The chest leads exhibited negative concordance of the P′ wave.

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  FIGURE 2. (A) The activation map (LAO caudal) shows early activation in the lower RA, but the exact earliest activation site could not be identified. The (*) indicates the earliest activation sites within the mapped area. (B) In the electrogram from the earliest activation site (*) recorded by the Octaray mapping catheter, unipolar potentials presented an rS pattern, with no QS pattern detected. (C) The left panel shows the P wave during tachycardia, and the right panel shows the P wave during pacing at the highest‐scoring site. The polarity matched across all leads. (D) iPASO map (LAO caudal). The highest ICPM matching score is found on the CTI, 10.3 mm away from the tricuspid valve. Further, the scores for the surrounding areas are lower, with the iPASO map exhibiting a centrifugal pattern. (E) The dual‐chamber (RA and CS) unipolar electrograms obtained from pace mapping at the three sites shown in Figure 2C, reference EGMs of the clinical PAC, and matching scores calculated by the ICPM. The matching scores for the three sites calculated by the ICPM were ① 0.75, ② 0.70, and ③ 0.91, respectively. (F) RF application sites on the three‐dimensional anatomical map (RAO view). During RF…