High-density mapping for ablation of atypical atrial flutters - procedural characteristics related to outcome
Bob G S Abeln1,2, Jippe C Balt1, Martijn N Klaver1,2
1Cardiology Department, St. Antonius Hospital, Nieuwegein, The Netherlands.
Insights
High-density mapping successfully identified most atypical atrial flutter circuits. Ablation led to 61% freedom from recurrence, with critical isthmus ablation improving long-term outcomes.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- High-density (HD) mapping is increasingly utilized for characterizing arrhythmic substrates in atypical atrial flutters (AAFl).
- Clinical outcomes and factors influencing arrhythmia recurrence after HD mapping-guided ablation for AAFl remain under-researched.
Purpose of the Study:
- To evaluate the clinical outcomes of catheter ablation for AAFl guided by HD mapping.
- To identify factors associated with atrial flutter recurrence after ablation.
Main Methods:
- A single-center, prospective, observational cohort study.
- Enrolled patients undergoing catheter ablation for AAFl using HD mapping and a grid-shaped catheter.
- Assessed procedural characteristics, recurrence rates, and associated factors.
Main Results:
- HD mapping identified flutter circuits in 80/94 AAFl cases.
- 61% of patients (37/61) remained free from AAFl recurrence over a median follow-up of 1.3 years.
- Critical isthmus ablation was associated with reduced recurrence (HR:0.4; P=.04), while non-identified circuits showed a trend towards increased recurrence (HR:2.4; P=.06).
Conclusions:
- HD mapping effectively identifies the majority of AAFl circuits.
- Ablation guided by HD mapping achieved freedom from recurrence in 61% of patients.
- Successful identification of flutter circuits and ablation of critical isthmuses appear crucial for favorable long-term outcomes in AAFl management.
Background:
High-density (HD) mapping is increasingly used to characterize arrhythmic substrate for ablation of atypical atrial flutters (AAFl). However, results on clinical outcomes and factors that are associated with arrhythmia recurrence are scarce.
Methods:
Single-center, prospective, observational cohort study that enrolled patients with catheter ablation for AAFl using a HD mapping system and a grid-shaped mapping catheter. Procedural characteristics, rates of atrial flutter recurrence, and factors that were associated with atrial flutter recurrence were evaluated.
Results:
Sixty-one patients with a total of 94 AAFl were included in the cohort. HD mapping was used to successfully identify the flutter circuit of 80/94 AAFl. The circuit was not identified for 14/94 AAFl in 11 patients. Critical isthmuses were identified and ablated in 29 patients (48%). Acute procedural success was achieved in 52 patients (85%), and 37 patients (61%) remained free from atrial flutter recurrence during a follow up of 1.3 [1.0-2.1] years. Atrial flutter recurrence was univariably associated with presence of a non-identified flutter circuit (HR:2.6 95% CI [1.1-6.3], p = .04) and critical isthmus-targeted ablation (HR:0.4 [0.15-0.90], p = .03). In multivariable regression analyses, critical isthmus ablation remained significant (HR:0.4 [0.16-0.97], p = .04), whereas presence of a non-identified flutter did not (HR:2.4 [0.96-5.8], p = .06).
Conclusion:
HD mapping was successfully used to identify the majority of AAFl circuits. Ablation resulted in freedom from atrial flutter recurrence in 61% of the cohort. Successful identification of all flutter circuits and critical isthmuses appears to be beneficial for long-term outcomes.
