Abstract:
Background: Atypical Atrial Flutter (AAFL) prevalence is
increasing due to the escalating Atrial Fibrillation (AF) ablations and
cardiac surgeries. We wanted to explore the outcome of the AAFL
ablation, considering the recent changes in mapping and ablation.
Methods: This study was approved by the Institutional Review
Board (IRB) of Mayo Clinic hospital. We retrospectively studied 419
patients who had undergone AAFL ablation at Mayo Clinic from January
2017 to June 2022. Thirteen patients declined research authorization,
and 19 patients were lost to follow-up during the 90-day blanking
period, resulting in a sample size of 387. The median follow-up time for
patients was 25.7 months (95% CI 23.7, 32.3).
Results: Recurrent symptoms with documentation of atrial
arrhythmia Occurred in 226/387 (58.4%) patients, of which 151/226
(66.8%) occurred within the first year. The median time to recurrence
was 8.5 months (max 57.8 months). Eleven patients died during the study
period, 9 of whom experienced recurrence prior to death. Overall, the
median recurrence-free survival (RFS) time was 16.6 months (95% CI
13.2, 20.0) with a 1-year RFS rate of 57.2% (95% CI 52.2, 62.7%).
Acute termination occurred 324/387 (83.7%) during the ablation. The
1-year RFS rate was 58.9% (95% CI 53.5%, 64.9%) for patients with
acute termination and 49.0% (95% CI 37.9%, 63.4%) for those without
acute termination. The rate was not significantly different based on
acute termination status (p = 0.11).
Conclusions: The one-year RFS rate of 57.2% following AAFL
ablation, even though 83.7% achieved acute termination during the
procedure, signifies the extent of the underlying substrate
abnormalities.
Keywords: Atypical atrial flutter, Atypical atrial flutter
ablation, Atrial fibrillation, Radiofrequency ablation, AV-nodal
ablation, Pacemaker, Mitral valve repair, Surgical MAZE procedure,
Structural heart defect.