title: Periodic conduction and 2:1 block from the left atrium to the pulmonary vein during radiofrequency ablation.
abstract: Paroxysmal atrial fibrillation is often initiated by foci in the pulmonary veins (PVs); the junction between the PVs and the left atrium (LA) has become the target of radiofrequency (RF) ablation performed to isolate the PVs. Ectopic atrial beats originating from the PVs propagate to the LA with a characteristically long conduction time, often with a conduction delay or block within the PV or at the PV-LA junction. However, details about the conduction properties within the PVs and across the PV-LA junction are still scanty. We report a unique case of LA-PV decremental conduction caused by RF applications. New insights into the electroanatomical characteristics of the PV-LA junction are provided. The present report demonstrates, for the first time in humans, that decremental conduction may be related to the progressive damage of the conducting myocardial bundle due to RF energy applications.
authors.affiliation: Electrophysiology and Arrhythmia Unit, Department of Cardiology, IRCCS Policlinico San Matteo, Pavia, Italy. elettrofisiologia@smatteo.pv.it
authors.forename: Maurizio
authors.initials: M
authors.lastname: Landolina
authors.forename: Barbara
authors.initials: B
authors.lastname: Petracci
authors.forename: Gaetano M
authors.initials: GM
authors.lastname: De Ferrari
authors.forename: Folco
authors.initials: F
authors.lastname: Frattini
authors.forename: Francesco
authors.initials: F
authors.lastname: Cantù
authors.forename: Roberto
authors.initials: R
authors.lastname: Rordorf
authors.forename: Paolo
authors.initials: P
authors.lastname: De Filippo
mesh_terms: D001281:Atrial Fibrillation / Q000209:etiology* / Q000503:physiopathology; D017115:Catheter Ablation / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000002:abnormalities*; D006801:Humans; D008875:Middle Aged; D011667:Pulmonary Veins