Reduced Left Atrial Appendage Flow Is Associated With Future Atrial Fibrillation After Cryptogenic Stroke

Area of Science:

• Cardiology
• Neurology
• Medical Imaging

Background:

• Left atrial appendage (LAA) hemostasis is a significant stroke risk factor, particularly in patients with atrial fibrillation (AF).
• While LAA flow dynamics offer insights into LAA function, their predictive value for AF development remains underexplored.
• This study investigates the association between early LAA peak flow velocities post-cryptogenic stroke and the subsequent incidence of AF.

Purpose of the Study:

• To determine if LAA peak flow velocities measured early after cryptogenic stroke can predict the future development of atrial fibrillation (AF).
• To assess the utility of LAA flow dynamics as a biomarker for AF in cryptogenic stroke patients.

Main Methods:

• 110 cryptogenic stroke patients underwent transesophageal echocardiography for LAA pulsed-wave Doppler flow assessment.
• LAA velocities were analyzed by a blinded investigator.
• Patients were monitored for AF using 7-day Holter and implantable devices for up to 1.5 years.

Main Results:

• During follow-up, 38% of patients developed AF.
• Lower LAA filling and emptying velocities (LAAev) were observed in patients who developed AF compared to those who did not (P < .001).
• LAAev demonstrated a strong association with future AF (AUC 0.88), with an optimal cutoff of 55 cm/sec. Age and mitral regurgitation independently predicted reduced LAAev.

Conclusions:

• Impaired LAA emptying velocity (LAAev < 55 cm/sec) in cryptogenic stroke patients is associated with an increased risk of future AF.
• This finding may help identify patients who would benefit from extended rhythm monitoring, enhancing diagnostic accuracy and timely intervention.