High-Power Radiofrequency Catheter Ablation of Atrial Fibrillation: Using Late Gadolinium Enhancement Magnetic Resonance Imaging as a Novel Index of Esophageal Injury.

OBJECTIVES: This study retrospectively evaluated the feasibility and esophageal thermal injury (ETI) patterns of high-power short-duration (HPSD) radiofrequency atrial fibrillation (AF) ablation.
BACKGROUND: ETI following AF ablation can lead to serious complications. Little consensus exists on the optimal radiofrequency power setting or on the optimal strategy to assess ETI.
METHODS: A total of 687 patients undergoing first-time AF ablation with either HPSD ablation (50 W for 5 s, n = 574) or low-power long-duration ablation (LPLD, ≤35 W for 10 to 30 s, n = 113) were analyzed. ETI was assessed by late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) within 24 h post-ablation. Patients with moderate or severe esophageal LGE had a follow-up MRI within 24 h to 1 week, and esophagogastroduodenoscopies were performed when significant gastrointestinal symptoms or persistent LGE on repeat MRI was present. AF recurrence adjusted for potential confounders was analyzed.
RESULTS: The average age was 69.0 ± 11.8 years in the group undergoing HPSD ablation versus 68.3 ± 11.6 years in the LPLD group (p = 0.554), with 67.1% versus 59.3% male (p = 0.111). Esophageal LGE patterns were similar (64.8% vs. 57.5% none, 21.0% vs. 28.3% mild, 11.5% vs. 11.5% moderate, 2.8% vs. 2.7% severe for HPSD vs. LPLD, respectively; p = 0.370) with no atrioesophageal fistulas. Mean procedure length was significantly shorter in the HPSD group (149 ± 65 min vs. 251 ± 101 min; p < 0.001). AF recurrence rates were similar in the 2 groups for the mean 2.5-year follow-up period (adjusted, 42% vs. 41%; p = 0.571).
CONCLUSIONS: HPSD ablation results in similar ETI patterns, as assessed by same-day LGE MRI, compared with the LPLD setting but with significantly shorter procedure times. Recurrence rates at 2.5-year follow-up are similar.