Pulmonary vein anatomy in patients undergoing catheter ablation of atrial fibrillation: lessons learned by use of magnetic resonance imaging.
BACKGROUND
This study sought to define the technique and results of magnetic resonance imaging (MRI) of pulmonary vein (PV) anatomy before and after catheter ablation of atrial fibrillation (AF).


RESULTS
Twenty-eight patients with AF underwent ablation. Patients underwent gadolinium-enhanced MRI before and 6 weeks after their procedures. A control group of 27 patients also underwent MRI. Variant PV anatomy was observed in 38% of patients. AF patients had larger PV diameters than control subjects, but no difference was observed in the size of the PV ostia among AF patients. The PV ostia were oblong in shape with an anteroposterior dimension less than the superoinferior dimension. The left PVs had a longer "neck" than the right PVs. A detectable PV narrowing was observed in 24% of veins. The severity of stenosis was severe in 1 vein (1.4%), moderate in 1 vein (1.4%), and mild in 15 veins (21.1%). All patients were asymptomatic, and none required treatment.


CONCLUSIONS
This study demonstrates that AF patient have larger PVs than control subjects and demonstrates the value of MRI in facilitating AF ablation. The benefits of preprocedural MRI of PVs include the ability to evaluate the number, size, and shape of the PVs. MRI also provides an assessment of the severity of PV stenosis.
Kato
Ritsushi
R
Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Lickfett
Lars
L
Meininger
Glenn
G
Dickfeld
Timm
T
Wu
Richard
R
Juang
George
G
Angkeow
Piamsook
P
LaCorte
Jennifer
J
Bluemke
David
D
Berger
Ronald
R
Halperin
Henry R
HR
Calkins
Hugh
H
D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011667:Pulmonary Veins / Q000033:anatomy & histology*; D011668:Pulmonary Veno-Occlusive Disease / Q000175:diagnosis*; D016896:Treatment Outcome; D014654:Vascular Patency