The cardiology community is revisiting how best to treat patients with persistent AFib in light of new evidence that suggests targeting low-voltage areas in the left atrium may be a valuable addition to pulmonary vein isolation.
The self-funded ERASE AF study found that targeting low-voltage areas in the left atrium in addition to pulmonary vein isolation (PVI) effectively improved AFib suppression.
When AFib is persistent, there is often structural atrial disease present which impedes conduction, causing PVI to underperform in these patients. And yet, before the present ERASE AF trial, evidence suggested that additional ablation beyond PVI did not improve outcomes (STAR-AF-2, DECAAF-2, STABLE-SR-II).
In the present trial, 324 patients with persistent AFib were randomly assigned to either PVI alone or PVI plus substrate modification (PVI + SM) groups. SM is an ablation technique that isolates any areas of low voltage.
- Those who received PVI + SM were 38% less likely to experience a recurrence of AFib that lasted 30 seconds or more.
- An analysis of patients with implanted loop monitors (the most sensitive AFib detection monitor) also found less AFib in the PVI + SM group compared to the PVI alone group (55% vs. 39%).
- Adverse events were slightly more likely in the PVI + SM group compared to the PVI alone group (3.7% vs. 1.8%), but the difference was not statistically significant.
The debate around persistent AFib treatment has continued among electrophysiologists for decades. Contrary to existing evidence that shows additional ablation beyond PVI has no benefit, this RCT found that electrically isolating areas of low-voltage did improve AFib suppression. Although this study alone probably isn’t enough for EPs to wholeheartedly embrace the more aggressive ablation strategy, these findings will likely inform future AFib ablation trials.