Recurrence of atrial fibrillation correlates with the extent of post-procedural late gadolinium enhancement: a pilot study.
OBJECTIVE
We sought to evaluate radiofrequency (RF) ablation lesions in atrial fibrillation (AF) patients using cardiac magnetic resonance (CMR), and to correlate the ablation patterns with treatment success.


BACKGROUND
RF ablation procedures for treatment of AF result in localized scar that is detected by late gadolinium enhancement (LGE) CMR. We hypothesized that the extent of scar in the left atrium and pulmonary veins (PV) would correlate with moderate-term procedural success.


METHODS
Thirty-five patients with AF, undergoing their first RF ablation procedure, were studied. The RF ablation procedure was performed to achieve bidirectional conduction block around each PV ostium. AF recurrence was documented using a 7-day event monitor at multiple intervals during the first year. High spatial resolution 3-dimensional LGE CMR was performed 46 +/- 28 days after RF ablation. The extent of scarring around the ostia of each PV was quantitatively (volume of scar) and qualitatively (1: minimal, 3: extensive and circumferential) assessed.


RESULTS
Thirteen (37%) patients had recurrent AF during the 6.7 +/- 3.6-month observation period. Paroxysmal AF was a strong predictor of nonrecurrent AF (15% with recurrence vs. 68% without, p = 0.002). Qualitatively, patients without recurrence had more completely circumferentially scarred veins (55% vs. 35% of veins, p = NS). Patients without recurrence more frequently had scar in the inferior portion of the right inferior pulmonary vein (RIPV) (82% vs. 31%, p = 0.025, Bonferroni corrected). The volume of scar in the RIPV was quantitatively greater in patients without AF recurrence (p < or = 0.05) and was a univariate predictor of recurrence using Cox regression (p = 0.049, Bonferroni corrected).


CONCLUSIONS
Among patients undergoing PV isolation, AF recurrence during the first year is associated with a lesser degree of PV and left atrial scarring on 3-dimensional LGE CMR. This finding was significant for RIPV scar and may have implications for the procedural technique used in PV isolation.
Peters
Dana C
DC
Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA. dcpeters@bidmc.harvard.edu
Wylie
John V
JV
Hauser
Thomas H
TH
Nezafat
Reza
R
Han
Yuchi
Y
Woo
Jeong Joo
JJ
Taclas
Jason
J
Kissinger
Kraig V
KV
Goddu
Beth
B
Josephson
Mark E
ME
Manning
Warren J
WJ
D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000473:pathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects*; D002921:Cicatrix / Q000209:etiology / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006325:Heart Atria / Q000473:pathology / Q000601:surgery; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011667:Pulmonary Veins / Q000473:pathology / Q000601:surgery*; D012008:Recurrence; D018570:Risk Assessment; D013997:Time Factors; D017211:Treatment Failure
D003287:Contrast Media; D019786:Gadolinium DTPA