Durable lesion formation while avoiding esophageal injury during ablation of atrial fibrillation: Lessons learned from late gadolinium MR imaging.
INTRODUCTION
Adequate catheter/atrial tissue contact is critical for lesion formation during radiofrequency (RF) ablation of atrial fibrillation (AF). Late gadolinium enhancement magnetic resonance imaging (LGE-MRI) is a unique tool for the evaluation of lesion formation and detection of acute esophageal injury.


METHODS
LGE-MRIs were obtained prior, within 24 hours of, and at 115 ± 62 days after first AF ablation in 36 patients. The Visitag module of CARTO3 was used to collect contact force (CF) and duration from a CF sensing ablation catheter for each registered ablation point. The minimum CF resulting in permanent lesions was determined. Esophageal enhancement detected by acute LGE-MRI was classified as mild, moderate, and severe. The CF resulting in esophageal enhancement was determined.


RESULTS
A total of 4,642 registered ablation tags at 50 W power were analyzed. The mean RF duration (5.9 ± 3.7 vs. 5.6 ± 3.2 seconds, P < 0.05), CF (11.5 ± 5.6 vs. 10.9 ± 5.4 g, P < 0.001), and force time integral (FTI) (67.3 ± 54.5 vs. 62.2 ± 52.7 gs, P < 0.01) were significantly higher between ablation tags with and without associated LGE-MRI detected scar. The mean CF (15.7 ± 6.1 vs. 12.6 ± 5.9 g, P < 0.05, n  =  17 patients) in areas of esophageal enhancement was greater than areas without.


CONCLUSION
Left atrial short duration ablation lesions with a CF greater than 12 g are more likely to be associated with permanent lesion formation. Ablating on top of the esophagus, CF less than 15 g would help minimize esophageal wall injury.
['Chelu|Mihail G|MG|', 'Morris|Alan K|AK|', 'Kholmovski|Eugene G|EG|', 'King|Jordan B|JB|', 'Kaur|Gagandeep|G|', 'Silver|Michelle A|MA|', 'Cates|Joshua E|JE|', 'Han|Frederick T|FT|', 'Marrouche|Nassir F|NF|0000-0003-0970-9182']
D000368:Aged D001281:Atrial Fibrillation D017115:Catheter Ablation D002921:Cicatrix D003287:Contrast Media D004947:Esophagus D005260:Female D005355:Fibrosis D006325:Heart Atria D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008536:Meglumine D008875:Middle Aged D061646:Operative Time D009942:Organometallic Compounds D011237:Predictive Value of Tests D012189:Retrospective Studies D012307:Risk Factors D013997:Time Factors D016896:Treatment Outcome D014947:Wounds and Injuries
ablation atrial fibrillation LGE-MRI atrial fibrosis force sensing catheter