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

BACKGROUND/PURPOSE: 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.