Interatrial Conduction in Patients with Paroxysmal Atrial Fibrillation and in Healthy Subjects
-
1
Helsinki University Central Hospital, Department of Cardiology, Finland
-
2
Helsinki University Central Hospital, HUSLAB BioMag Laboratory, Finland
Background: Altered atrial conduction is linked to susceptibility to atrial fibrillation (AF). Intra-atrial recordings in patients have confirmed the occurrence of 3 distinct sites of electrical connection from the right atria (RA) to the left atria (LA) and the high inter-individual variation of these connections. Whether signal propagation to LA during sinus rhythm differs between patients with paroxysmal AF and healthy subjects is not known and cannot be examined invasively. Methods: By magnetocardiography (MCG) the atrial signal can be evaluated non-invasively. We have shown that in the time intervals representing RA and LA activation, the MCG pseudocurrent angle represents the direction of propagation. Based on magnetic field orientations in the MCG maps over time intervals corresponding to early and later LA activations, MCG atrial waves can be classified into 3 types which are related to distinct interatrial conduction routes: Type 1 to Bachmann bundle, Type 2 to margin of fossa ovalis or multisite, and Type 3 to coronary sinus ostial connections. Recently we applied the method in a population comprising 107 patients with lone paroxysmal AF (age 45±12 years) and 94 controls. A 99-channel MCG was recorded over anterior chest. The duration of the atrial wave (Pd) and the MCG atrial wave type were determined. Results: Pd was longer in AF patients than in controls (112±13 vs. 104±13; p<0.001), which was most obvious in Type 1 wave (109±12 vs. 102±11 ms, p=0.003). The distribution of the atrial wave types differed between AF patients and controls: Type 1 occurred in 67% and Type 2 in 20% of controls whereas Type 1 occurred in 54% and Type 2 in 42% of AF patients, p<0.01 for difference. Conclusions: Susceptibility to paroxysmal lone AF is associated with propagation of atrial signal to LA via margin of fossa ovalis or multiple pathways. When conduction occurs via Bachmann bundle, it is related with prolonged atrial activation. Thus altered and alternative conduction pathways may contribute to pathogenesis of lone AF.
Conference:
Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010.
Presentation Type:
Oral Presentation
Topic:
MCG: Instrumentation, Modeling, Basic and Clinical Studies
Citation:
Jurkko
R,
Mäntynen
V,
Lehto
M,
Tapanainen
JM,
Montonen
J,
Parikka
H and
Toivonen
L
(2010). Interatrial Conduction in Patients with Paroxysmal Atrial Fibrillation and in Healthy Subjects.
Front. Neurosci.
Conference Abstract:
Biomag 2010 - 17th International Conference on Biomagnetism .
doi: 10.3389/conf.fnins.2010.06.00313
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
06 Apr 2010;
Published Online:
06 Apr 2010.
*
Correspondence:
Raija Jurkko, Helsinki University Central Hospital, Department of Cardiology, Helsinki, Finland, raija.jurkko@2me.fi