LVEF Improvement After Ablation Despite Persistent AF Episodes
Yes, LVEF caused by persistent longstanding atrial fibrillation can improve after catheter ablation even when some AF episodes persist, though the degree of improvement is strongly associated with achieving sinus rhythm and depends critically on baseline cardiac substrate.
Evidence from Major Trials
The most robust evidence comes from the CASTLE-AF trial 1, which demonstrated that catheter ablation led to a significant improvement in LVEF at 5 years compared with medical therapy (+8.0% vs. +0.2%, P = 0.005). Critically, this benefit was driven primarily by ablation of persistent AF (+10% vs. -2.5%, P = 0.004) rather than paroxysmal AF. Importantly, 68% of patients in the ablation group showed an increase in LVEF beyond 35%, even though only 63% maintained stable sinus rhythm at 5 years 1. This indicates that LVEF improvement can occur even without complete elimination of AF.
The AATAC-AF trial showed similar findings, with LVEF improvement significantly higher in the ablation arm (8% vs. 6%, P = 0.02), and this improvement was associated with but not absolutely dependent on freedom from AF recurrence 1.
Key Predictors of LVEF Recovery
Factors Favoring Improvement:
- Left ventricular end-diastolic diameter (LVDd) <59 mm 2
- Absence of low voltage zones in the left atrium 2
- Minimal ventricular fibrosis on cardiac MRI (R²=-0.67 correlation with LVEF change) 3
- Earlier stage heart failure (LVEF ≥25% shows better outcomes than <25%) 1
- Younger patients without significant comorbidities 4
Factors Predicting Poor Response:
- Advanced heart failure with extensive ventricular scar 1
- Severe atrial myopathy (dilation/fibrosis) 4
- Baseline LVEF <25% (HR 1.36 vs. HR 0.48 for LVEF ≥25%) 1
Clinical Implications
The 2019 European Heart Journal guidelines 1 emphasize that restoration of sinus rhythm after catheter ablation significantly improved LV function, exercise capacity, symptoms, and quality of life (usually within the first 3 to 6 months), even in the presence of concurrent heart disease and when ventricular rate control was adequate before ablation 5.
However, the 2024 ACC/AHA/HRS guidelines 4 recommend catheter ablation specifically in patients with AF and HFrEF with high probability of tachycardia-induced cardiomyopathy to reverse left ventricular dysfunction (Class I recommendation).
Important Caveats
The AMICA Trial Exception:
The AMICA trial 6 was terminated early for futility, showing no difference in LVEF improvement between ablation (8.8%) and best medical therapy (7.3%) at 1 year. This trial enrolled patients with more advanced heart failure (all had ICD/CRT-D indications, LVEF ≤35%), suggesting that in severely advanced HF, the benefit of ablation may be limited regardless of rhythm outcome.
Rhythm Burden Still Matters:
While some LVEF improvement can occur despite AF recurrence, the degree of improvement correlates with AF burden reduction. In CASTLE-AF, device-recorded AF burden at 1 year was 0% or ≤5% in 72% of ablation patients vs. 44% of medical therapy patients 1. Greater AF burden reduction, even if not complete elimination, appears to drive better LVEF recovery 7, 8.
Practical Algorithm for Decision-Making
Proceed with ablation if:
- LVDd <59 mm AND
- No/minimal low voltage zones on mapping AND
- No/mild ventricular fibrosis on CMR AND
- LVEF ≥25% AND
- Earlier stage HF (NYHA II-III, not IV)
Consider alternative strategies if:
- Advanced HF with significant ventricular scar
- Severe atrial myopathy
- LVEF <25%
- Multiple failed ablations
In these cases, consider AV nodal ablation + biventricular pacing (Class IIa-B) 1.
Bottom Line
LVEF improvement after ablation is possible even with some persistent AF episodes, but the magnitude of benefit depends on baseline cardiac substrate and degree of AF burden reduction. The 2024 ESC guidelines 9 recommend catheter ablation in patients with AF and HFrEF with high probability of tachycardia-induced cardiomyopathy (Class I), recognizing that rhythm control through ablation provides superior outcomes compared to rate control alone 1, 10, 11. However, patient selection is critical—those with advanced structural disease and extensive fibrosis are less likely to benefit, regardless of rhythm outcome 1.