Evaluation of cerebral blood flow in acute ischemic stroke patients with atrial fibrillation: A sonographic study

Abstract

Although cerebral emboli are a frequent cause of cardiogenic stroke, the possibility of a reduction in cerebral perfusion consequent to arrhythmia or impaired cardiac function should be considered in patients with atrial fibrillation (AF). Methods: We reviewed sonographic studies and clinical features of patients with acute ischemic stroke. A total of 144 patients with AF and 144 age- and sex-matched patients with small vessel occlusion but without AF were included. Results: Patients with AF had significantly lower peak systolic velocity (PSV), mean velocity, flow volume (p < 0.001), and end-diastolic velocity (p = 0.035) of the internal carotid artery (ICA); significantly lower cerebral blood flow (p < 0.001); and lower flow velocities of the middle cerebral artery (p < 0.01) than patients with small vessel occlusion but without AF. In patients with AF, there was an inverse linear correlation between ICA end-diastolic velocity, mean velocity (p < 0.001), flow volume (p = 0.025), middle cerebral artery flow velocities (p < 0.05), and age. Cardiac ejection fraction had a positive linear correlation with ICA PSV (p = 0.016) but an inverse correlation with the heart rate (p = 0.009). There was a significant decline in PSV (p = 0.002), resistance index (p < 0.001), and flow volume (p = 0.0121) of the ICA as well as cerebral blood flow (p = 0.009) as the heart rate increased. Conclusion: Cerebral blood flow is markedly reduced in ischemic stroke patients with AF as compared with that in patients with small vessel disease but without AF.

Keywords

• atrial fibrillation
• cerebral blood flow
• color-coded carotid duplex sonography
• ischemic stroke
• transcranial color-coded duplex sonography