Ocular blood flow dynamics following sinus rhythm restoration through catheter ablation: laser speckle flowgraphy in patients with persistent atrial fibrillation

Abstract

Aims: Laser speckle flowgraphy (LSFG) is a well-established tool renowned for its non-invasive and reproducible assessment of ocular blood flow. While rhythm control therapies, such as catheter ablation (CA), have shown promise in enhancing cognitive function in atrial fibrillation (AF) patients, the acute impact of CA on microcirculatory changes, particularly in ocular blood flow, remains a topic of limited understanding. The present study aims to delve into the potential of LSFG in detecting microcirculatory alterations following the restoration of sinus rhythm (SR) through CA in patients with AF.

Methods and results: We studied 8 paroxysmal AF (Paf) and 20 persistent AF (PeAF) patients (mean age 67 ± 6 years, 26% female) undergoing CA. Ocular blood flow was assessed using LSFG by measuring the mean blur rate (MBR) pre- and post-CA. Post-CA, all PeAF patients achieved SR restoration, resulting in a significant increase in tissue MBR (10.0 ± 2.2 to 10.8 ± 2.9, P = 0.021). In contrast, Paf patients showed no significant difference between pre- and post-MBR (12.0 ± 2.7 vs. 11.8 ± 2.6, P = 0.76).

Conclusion: LSFG analysis effectively identified microcirculatory changes in patients undergoing CA for PeAF, suggesting that therapeutic interventions targeting the heart may have broader implications for ocular and cerebral health, establishing a novel 'cardio-oculo-cerebral relationship'.

Keywords: LSFG; atrial fibrillation; catheter ablation; cognitive impairment; microcirculation; ocular blood flow.

Graphical Abstract

Figure 1

Ocular blood flow changes detected by LSFG analysis in patients undergoing catheter ablation for atrial fibrillation. LSFG uses a laser to assess fundus blood flow, where scattering rays create a distinctive speckled pattern known as the speckle phenomenon. This pattern changes with blood flow, quantified as the MBR. Representative images demonstrate ocular blood flow in patients with AF. (A–C) show data from PeAF patients, while (D–F) present data from Paf patients. Specifically, (A and D) show conditions before catheter ablation, and (B and E) show conditions after catheter ablation in SR. (C and F) demonstrate changes in MBR. MBR reflects retinal blood flow velocity, with the red-dotted line indicating the average change. Group comparisons were conducted using the Wilcoxon signed-rank test, considering P < 0.05 as statistically significant. LSFG, laser speckle flowgraphy; CA, catheter ablation; AF, atrial fibrillation.