Complete interatrial block in a left-atrial dependent atrioventricular node
Javier Ramos Jiménez1, Álvaro Marco Del Castillo1, Daniel Rodríguez Muñoz1
1Arrhythmia and Electrophysiology Unit, Cardiology Department, University Hospital 12 de Octubre, Madrid, Spain.
Introduction:
A middle-age woman underwent an electrophysiologic study due to recurrent atypical atrial flutter.
Methods And Result:
Radiofrequency ablation of cavotricuspid isthmus and anterior mitral line was performed. During energy delivery on the anterior left atrial wall, interatrial dissociation and complete block of the sinus impulse to the atrioventricular (AV) node was observed. AV node activation became dependent on a subsidiary left atrial rhythm.
Conclusion:
Anatomical location of intra and inter-atrial connections must be taken into account when performing extensive ablation procedures, specially in cases with prior cardiac surgeries.
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