Low-Voltage Ablation Improves Persistent AF Control

Individualized ablation of low-voltage areas improved rhythm outcomes when added to pulmonary vein isolation (PVI) for selected patients with persistent atrial fibrillation (AF), according to the randomized IDEAL-AF trial published in JAMA.

The multicenter Swedish trial enrolled 978 adults scheduled for first-time ablation. Of these, 936 underwent PVI with voltage mapping; 209 who had at least 1 left atrial low-voltage zone measuring 3.0cm² or greater were randomized. Participants received PVI alone or PVI followed by ablation tailored to the location and extent of the low-voltage substrate.

At 12 months, freedom from documented atrial arrhythmia without antiarrhythmic drugs after 1 or 2 procedures, with any repeat procedure performed within 6 months, was achieved by 67.6% of patients assigned to low-voltage zone ablation and 37.4% assigned to PVI alone. The unadjusted difference was 30.3 percentage points (95% CI, 17.4-43.2), and the unadjusted odds ratio was 3.5 (95% CI, 2.0-6.2; P<0.001). Time to first recurrence after a single procedure also favored adjunctive ablation.

Health-related quality of life improved more in the substrate-guided group. Serious adverse events occurred in 9.8% of patients receiving low-voltage zone ablation and 7.5% receiving PVI alone, a difference that was not statistically significant (P=0.48).

The findings apply to patients with persistent AF and substantial low-voltage substrate identified during electroanatomic mapping. The trial does not establish that additional substrate ablation benefits patients without those mapped abnormalities.

Source: Paul Nordin A, Charitakis E, Carnlöf C, et al. Low-voltage ablation in persistent atrial fibrillation: the IDEAL-AF randomized clinical trial. JAMA. Published online August 30, 2026. doi:10.1001/jama.2026.17274