title: Simultaneous Accessory Pathway and AV Node Mechanical Block.
abstract: We report a clinical case of a 22-year-old female referred to our institution due to palpitations and preexcitation. Her ECG suggested a right superior paraseptal accessory pathway (AP), which was localised during the electrophysiological study at the superior paraseptal region in close proximity to the His recordings. Reproducible orthodromic reciprocating tachycardia was induced by atrial pacing with extrastimuli. Cryo-mapping performed in the area of earliest atrial activation was not able to terminate the tachycardia. A second attempt, slightly more posterior, caused mechanical block of the AP, which rendered the tachycardia non-inducible. More pressure with the ablation catheter determined a Wenckebach type supra-hisian AV block, which was transient but reproducible. Given this finding no ablation was done. Simultaneous block to the AP and the atrioventricular node has rarely been reported using radiofrequency energy. However, to our knowledge this phenomenon has not been previously reported in large series using cryo-thermal energy.
authors.affiliation: Unidad de Electrofisiología y Arritmias, Hospital Universitario "La Paz", Madrid, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Garofalo
authors.forename: Alfonso Gomez
authors.initials: AG
authors.lastname: Gallanti
authors.forename: David Filgueiras
authors.initials: DF
authors.lastname: Rama
authors.forename: Rafael Peinado
authors.initials: RP
authors.lastname: Peinado
keywords: Accessory pathway; Atrioventricular node; Block; Cryoablation; Orthodromic reciprocating tachycardia