Journal of Arrhythmia (Jan 2005)

Modes of Initiation of Two Types of Atrial Reentry in a Patient with Typical Atrial Flutter: Isthmus-dependent Micro-reentry versus Macro-reentry

  • Makoto Noda, MD,
  • Fumio Suzuki, MD,
  • Kazunori Sezaki, MD,
  • Tetsuya Katsuno, MD,
  • Michio Usui, MD,
  • Mitsuaki Isobe, MD

DOI
https://doi.org/10.1016/S1880-4276(05)80030-4
Journal volume & issue
Vol. 21, no. 3
pp. 422 – 426

Abstract

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We studied the modes of initiation of two types of atria] reentrant tachycardias (i.e., microreentry isthmus tachycardia and counterclockwise atrial flutter) in a 39-year-old male with typical atrial flutter. Rapid atrial pacing from proximal coronary sinus at a cycle length of 220 msec initiated micro-reentry isthmus tachycardia (non-sustained), while rapid atrial pacing at a cycle length of 210 msec initiated sustained atrial flutter circulating counterclockwise around the tricuspid annulus. It was suggested that initiation of the counterclockwise atrial flutter was associated with a pacing-induced conduction block in the entire width of the isthmus, whereas initiation of the micro-reentry isthmus tachycardia was associated with a pacing-induced conduction block in a limited segment of the isthmus (i.e., partial isthmus block).

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