The Particulars: The validity of delayed enhancement MRI (DE-MRI) in staging atrial fibrosis and helping determine treatment success in patients with atrial fibrillation (AF) has not been well-defined.

Data Breakdown: Among 260 patients with AF, study investigators performed high resolution DE-MRI up to 30 days before scheduled ablation to determine the presence and extent of atrial fibrosis. Post-ablation DE-MRI was performed at 90-days follow-up in 177 of the subjects to determine the extent of residual ablation. Pre-ablation atrial fibrosis stage and post-ablation residual fibrosis emerged as independent predictors of successful ablation. Risk of recurrent symptoms increased by 6.3% for every increased percentage of pre-ablation fibrosis and by 8.2% for ever percentage of residual fibrosis.

Take Home Pearls: DE-MRI prior to ablative treatment appears to help stage atrial fibrosis and predict the success of treatment in patients with AF. Pre-ablation fibrosis stage and post-ablation residual fibrosis appear to predict successful ablation or recurrent symptoms.