High resolution mapping of the pulmonary vein and the vein of Marshall during induced atrial fibrillation and atrial tachycardia in a canine model of pacing-induced congestive heart failure.
OBJECTIVE
The study examined the activations in the pulmonary veins (PVs) and the vein of Marshall (VOM) during atrial fibrillation (AF) in dogs with congestive heart failure (CHF).


BACKGROUND
The patterns of activation within the PVs and the VOM during AF in CHF are unclear.


METHODS
We induced CHF in nine dogs by rapid ventricular pacing. The patterns of activation during induced AF were studied one week after ceasing ventricular pacing.


RESULTS
The duration of induced AF averaged 80.7 +/- 177.3 s. The termination of low-amplitude fractionated activity in the PVs preceded the termination of AF in 25 of 29 episodes. High-density mapping (1-mm resolution) showed that the PV was activated by a focal wave front independent of left atrial (LA) activation in 22 AF episodes. Frequent intra-PV conduction blocks and multiple wave fronts in the PVs were recorded during 10 AF episodes. Focal activations were observed within the VOM in 4 of 12 episodes of AF. Three atrial tachycardia (AT) episodes originated from a focus within a PV. Histological studies showed extensive fibrosis in the PVs and in the atria. The PVs in five normal dogs did not have focal or fractionated activity during induced AF.


CONCLUSIONS
Atrial fibrillation in canine CHF is associated with independent focal activations in the PVs and the VOM, and with complex wave fronts within the PVs. The PVs may also serve as the origin of AT. These findings suggest that electrical and anatomical remodeling of the PVs and the VOM are important in the maintenance of AF and AT in dogs with CHF.
Okuyama
Yuji
Y
Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA.
Miyauchi
Yasushi
Y
Park
Angela M
AM
Hamabe
Akira
A
Zhou
Shengmei
S
Hayashi
Hideki
H
Miyauchi
Mizuho
M
Omichi
Chikaya
C
Pak
Hui Nam
HN
Brodsky
Lauren A
LA
Mandel
William J
WJ
Fishbein
Michael C
MC
Karagueuzian
Hrayr S
HS
Chen
Peng Sheng
PS
D000200:Action Potentials; D000818:Animals; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects; D017115:Catheter Ablation; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology*; D004195:Disease Models, Animal; D004285:Dogs; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac / Q000295:instrumentation / Q000379:methods*; D005355:Fibrosis; D006325:Heart Atria / Q000473:pathology / Q000503:physiopathology; D006329:Heart Conduction System; D006333:Heart Failure / Q000150:complications*; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology; D011667:Pulmonary Veins / Q000473:pathology / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted