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Dual-loop intra-atrial re-entry tachycardia in a patient with ischaemic cardiomyopathy

P Ott1

  • 1University of Arizona Health Sciences Center, Department of Medicine, Sarver Heart Center, Tucson 85724, USA. ottp@u.arizona.edu

Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups on Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology
|July 24, 2002
PubMed

Insights

Catheter ablation for atrial flutter in a patient with ischemic cardiomyopathy revealed a dual-loop re-entry circuit. This complex arrhythmia likely resulted from scar tissue following multiple cardiac surgeries.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Surgery

Background:

  • A 65-year-old male patient with ischemic cardiomyopathy and a history of three coronary artery bypass graft surgeries presented with recurrent atrial flutter.
  • The patient underwent catheter ablation to treat the persistent atrial flutter.

Observation:

  • Electrophysiological study identified an initial clockwise atrial flutter dependent on the tricuspid annulus/inferior vena cava isthmus.
  • During radiofrequency ablation, the atrial flutter transformed into a distinct right atrial free wall re-entry tachycardia without altering the cycle length or interrupting the arrhythmia.

Findings:

  • The transformation of atrial flutter into a new tachycardia suggests a dual-loop ('figure-of-eight') re-entry circuit.
  • This complex re-entry mechanism is potentially attributed to atrial scar tissue resulting from previous cardiac surgical procedures.

Implications:

  • Understanding dual-loop re-entry circuits is crucial for effective ablation strategies in complex atrial arrhythmias.
  • Atrial scar from prior surgeries can predispose patients to intricate re-entrant tachycardias, necessitating tailored electrophysiological assessments.

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