A novel diagnostic technique in para-Hisian pacing under rapid adenosine triphosphate injection: A rare case of septal accessory pathway in a coronary sinus diverticulum

Figures

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  Figure 1. Findings of electrophysiological study. A: Supraventricular tachycardia (SVT) induced by atrial premature stimulation (S1-S1 500 ms; S1-S2 300 ms; S2-S3 260 ms). B: Ventricular pacing showed the same retrograde atrial sequence. C: Premature ventricular stimulus during the His refractory period reset the SVT. CS = coronary sinus; HRA = high right atrium; RVA = right ventricular apex; S = stimulation.

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  Figure 2. Para-Hisian pacing (PHP) before catheter ablation and diagrams. A: PHP showed an atrioventricular nodal (AVN) pattern, but the atrial sequence is different for narrow and wide QRS. The earliest atrial sequence changed from His (red arrowhead) to CS (blue arrowhead). Both (a) and (b) show 2 pattern diagrams of PHP. B: PHP under rapid intravenous adenosine triphosphate (ATP) injection. The earliest atrial sequence changed from His (red arrowheads) to CS (blue arrowheads) with the atrial sequence change (red dotted arrows), but both show narrow QRS morphology. Both (a) and (b) show 2 pattern diagrams of PHP, respectively. CSD = coronary sinus diverticulum; other abbreviations as in Figure 1.

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  Figure 3. Para-Hisian pacing after catheter ablation. The stimulus-atrial interval was prolonged to 88 ms, with the same atrial sequence (red dotted arrows) from the narrow to the wide QRS during parahisian pacing after radiofrequency ablation. The earliest atrial sequence was still His (red arrowheads). An atrioventricular nodal pattern is shown. Abbreviations as in Figure 1.