Acquisition of the pulmonary venous and left atrial anatomy with non-contrast-enhanced MRI for catheter ablation of atrial fibrillation: Usefulness of two-dimensional balanced steady-state free precession.
BACKGROUND
Usually, the pulmonary venous and left atrial (PV-LA) anatomy is assessed with contrast-enhanced computed tomographic imaging for catheter ablation of atrial fibrillation (AF). A non-contrast-enhanced magnetic resonance (MR) imaging method has not been established. Three-dimensional balanced steady-state free precession (3D b-SSFP) sequences cannot visualize the PV-LA anatomy simultaneously because of the signal intensity defect of pulmonary veins. We compared two-dimensional (2D) b-SSFP sequences with 3D b-SSFP sequences in depicting the PV-LA anatomy with non-contrast-enhanced MR imaging for AF ablation.


METHODS
Eleven healthy volunteers underwent non-contrast-enhanced MR imaging with 3D b-SSFP and 2D b-SSFP sequences. The MR images were reconstructed on the 3D PV-LA surface image. Two experienced radiological technicians independently scored the multiplanar reformatted (MPR) images on a scale of 1-4 (from 1, not visualized, to 4, excellent definition). The overall score was a sum of 5 segments (LA and 4 PVs).


RESULTS
In the 2D b-SSFP method, MR imaging was successfully performed, and the 3D PV-LA surface image was precisely reconstructed in all healthy volunteers. The image score was significantly higher in the 2D b-SSFP method compared to the 3D b-SSFP method (19 [19; 20] vs. 12 [11; 15], p=0.004, for both observers). No PV signal intensity defects occurred in the 2D b-SSFP method.


CONCLUSIONS
The 2D b-SSFP sequence was more useful than the 3D b-SSFP sequence in adequately depicting the PV-LA anatomy.
Department of Radiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Yutaka
Y
Shigenaga
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Kunihiko
K
Kiuchi
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Katsunori
K
Okajima
Department of Radiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Kazushi
K
Ikeuchi
Department of Radiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Takayuki
T
Ikeda
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Akira
A
Shimane
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Kiminobu
K
Yokoi
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Jin
J
Teranishi
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Kousuke
K
Aoki
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Misato
M
Chimura
Department of Radiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Hideyuki
H
Masai
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Shinichiro
S
Yamada
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Yasuyo
Y
Taniguchi
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Yoshinori
Y
Yasaka
Department of Cardiology, Himeji Cardiovascular Center, 520 Kou, Saisho, Himeji, Hyogo, Japan.
Hiroya
H
Kawai
3D, three-dimensional; AF, atrial fibrillation; Atrial fibrillation; Balanced SSFP; CT, computed tomography; FA, flip angle; FOV, field of view; LAA, left atrial appendage; LSPV, left superior pulmonary vein; Left atrium; MPR, multiplanar reformatted; MR, magnetic resonance; Magnetic resonance imaging; PV–LA, pulmonary venous and left atrial; Pulmonary vein; SENSE, sensitivity encoding; TE, echo time; TR, repetition time; b-SSFP, balanced steady-state free precession