High-density mapping in catheter ablation for atrial fibrillation in Asia Pacific region: An observational study

Background: Few clinical studies of atrial fibrillation (AF) have focused on Asian patients; data are lacking on current mapping and ablation strategies in the Asia Pacific region (APAC).

Objective: The HD Mapping Observational Study (NCT04022954) was designed to characterize electroanatomic mapping (EAM) with market-released high-density mapping (HDM) catheters in subjects with AF in APAC.

Methods: Subjects undergoing HDM and indicated for radiofrequency ablation (RFA) to treat AF were prospectively enrolled in APAC. Data included mapping strategy and ablation targets. EAM was performed using one of two commercially available HDM catheters (Advisor™ HD Grid, Sensor Enabled™, Abbott [GRID] or Inquiry™ AFocus II™ Double Loop, Abbott [DL]). Procedure-related adverse events were collected.

Results: Two hundred subjects were enrolled at 15 centers: 164 with symptomatic paroxysmal (PAF) and 36 with symptomatic persistent (PersAF) AF for de novo ablation. GRID and DL were used in 186 and 14 cases, respectively. All subjects underwent voltage mapping, with conservative thresholds (low voltage ≤0.5 mV and very low voltage/electrical scar ≤0.1 mV) used in 60.2% and 35.4% of maps, respectively. Focal impulses, rotors, complex fractionated electrograms, and other substrate targets were each searched for in <3% of subjects. Median time to generate a map was 9.0 (Q1: 5.0, Q3: 13.0) minutes. Ablation strategy included pulmonary vein (PV) isolation in all, and non-PV triggers in 75/200 (37.5%) subjects. Five serious adverse events were reported.

Conclusions: The study demonstrated an efficient strategy with the feasibility and safety of using HDM during AF ablation procedures in APAC.