Improved cerebral blood flow and hippocampal blood flow in stroke-free patients after catheter ablation of atrial fibrillation

Introduction: Atrial fibrillation (AF) is a risk factor for reduced cerebral blood flow (CBF) and cognitive dysfunction, even in stroke-free patients. We aimed to test the hypothesis that CBF and hippocampal blood flow (HBF), measured with arterial spin labeling magnetic resonance imaging (MRI), improve after catheter ablation of AF to achieve sinus rhythm (SR). Methods: A total of 84 stroke-free patients (63.1 +/- 9.1 years; paroxysmal AF, n = 50; non-paroxysmal AF, n = 34) undergoing AF catheter ablation were included. MRI studies were done before, 3 months, and 12 months after the procedure with CBF and HBF measurements. Results: Baseline CBF and HBF values in 50 paroxysmal AF patients were used as controls. Baseline CBF was higher in patients with paroxysmal AF than with non-paroxysmal AF (100 +/- 32% vs. 86 +/- 28%, p = .04). Patients with non-paroxysmal AF had increased CBF 3 months after AF ablation (86 +/- 28% to 99 +/- 34%, p = .03). Differences in CBF and HBF were greater in the group with AF restored to SR (p < .01). Both CBF and HBF levels at 12 months were unchanged from the 3 months level. Successful rhythm control by catheter ablation was an independent predictor of an increase in CBF > 17.5%. The Mini-Mental State Examination score improved after ablation (p = .02). Conclusion: SR restoration with catheter ablation was associated with improved CBF and HBF at 3 months, maintenance of blood flow, and improved cognitive function at 12 months.