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Case Reports
. 2019 Mar 28;35(3):558-561.
doi: 10.1002/joa3.12177. eCollection 2019 Jun.

Tachycardia cycle length alternans caused by alternate conduction velocity on the slow conduction zone in a postoperative scar-related atrial tachycardia

Chen Su  1   2 , Menghui Liu  1   2 , Yuedong Ma  1   2 , Lichun Wang  1   2
Affiliations
Case Reports

Tachycardia cycle length alternans caused by alternate conduction velocity on the slow conduction zone in a postoperative scar-related atrial tachycardia

Chen Su et al. J Arrhythm. .

Abstract

The underlying mechanism for stable beat-to-beat cycle length variability (CL alternans) in scar-related atrial tachycardia (AT) had not been elucidated clearly. We described a case with postoperative dual-loop reentrant AT in right atrium. When the loop depended on cavo-tricuspid isthmus was blocked by ablation, the AT transformed into a CL alternate tachycardia. High density and resolution mapping revealed that the CL alternans was caused by the alternate conduction velocities at the slow conduct region. A further ablation line was created from the slow conduction zone to the inferior vena cave, and afterward no AT was inducible.

Keywords: atrial tachycardia; cycle length alternans; slow conduction zone.

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Conflict of interest statement

The authors declare no conflict of interests for this article.

Figures

Figure 1
Figure 1
Postoperative scar‐related AT with dual‐loop reentrant circuit configurated figure‐of‐eight. A, double potentials with longer isoelectric line were showed at sites 1‐5. Double potential without isoelectric line was showed at site 6. At the site the probe located (B:C4‐5), a long‐fractionated potential was showed. B, the white dots were the sites where the entrainment mappings were performed. The white numbers were the intervals (ms) of PPI‐TCL. The PPI‐TCL at the site “a” was 28 ms, similar to that at the other sites around tricuspid annulus, indicated this region was not a dead end. The long‐fractionated potential site was the exit. So, the loop 2 around the incision scar was existence (red line and arrow), and the loop 1 was a counter‐clockwise cavo‐tricuspid isthmus dependent reentrant circuit (white line and arrow)
Figure 2
Figure 2
Tachycardia cycle length alternans caused by alternated conduction velocity at the slow conduction zone. (A, B) the same circuit was shared at both CL 320 ms and 280 ms. The Point “a” and Point “b” in panel A were chosen in the upstream and the downstream of the slow conduction zone, respectively. C, The activation propagation times from Point “b” to Point “a” (b‐a, the yellow double‐headed arrows) were equal (130 ms) in the two alternate CL, but the time intervals from Point “a” to Point “b” (a‐b, the white double‐headed arrows) were alternate in accordance with the CL alternans. D, the long‐fractionated potentials at the slow conduction zone displayed an approximate long‐short alternation in accordance with the CL alternation
See this image and copyright information in PMC

References

    1. Anter E, McElderry TH, Contreras‐Valdes FM, Li J, Tung P, Leshem E, et al. Evaluation of a novel high‐resolution mapping technology for ablation of recurrent scar‐related atrial tachycardias. Heart Rhythm. 2016;13(10):2048–55. - PubMed
    1. Yang JD, Sun Q, Guo XG, Zhou GB, Liu X, Luo B, et al. Right atrial dual‐loop reentrant tachycardia after cardiac surgery: prevalence, electrophysiological characteristics, and ablation outcomes. Heart Rhythm. 2018;15(8):1148–57. - PubMed
    1. Takigawa M, Derval N, Maury P, Martin R, Denis A, Miyazaki S, et al. Comprehensive multicenter study of the common isthmus in post‐atrial fibrillation ablation multiple‐loop atrial tachycardia. Circ Arrhythm Electrophysiol. 2018;11(6):e6019. - PubMed
    1. Anter E, Tschabrunn CM, Josephson ME. High‐resolution mapping of scar‐related atrial arrhythmias using smaller electrodes with closer interelectrode spacing. Circ Arrhythm Electrophysiol. 2015;8(3):537–45. - PubMed
    1. Josephson ME, Anter E. Substrate mapping for ventricular tachycardia: assumptions and misconceptions. JACC Clin Electrophysiol. 2015;1(5):341–52. - PubMed

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