Hand gripping effect on cerebral blood flow in patients with ischemic stroke

Abstract

Purpose: We assessed the motor stimulus to blood flow velocity (BFV) changes of bilateral middle cerebral arteries (MCAs) by transcranial Doppler (TCD) sonography in patients with acute ischemic cerebrovascular events and normal subjects. Methods: Thirty-two patients (9 female, 23 male; aged 56.1 ±2.5 years) with acute ischemic cerebrovascular events in the MCA territory, and 17 (8 female, 9 male; aged 50.0±3.2 years) control subjects were investigated. Bilateral TCD sonography from both MCAs were monitored during 10 cycles of 20 seconds when subjects are performing hand gripping with a frequency of one per second, and subsequently 20 seconds when they are rest to assess BFV changes on activated cortical motor areas. BFV increase was calculated off-line for each subjects. Results: There is no significant age and gender difference between patients and controls. Eighteen patients had lacunar infarction, 7 patients had cortical and subcortical infarction, and 7 patients had cortical infarction. In the patients mean flow velocities, flow velocities at stimulation and flow velocities at rest were found significantly lower than that of controls on both side. In contrast to these results relative flow velocity increase was not significantly different between patients and controls. However, relative flow velocity increase was slightly lower on the lesion side in the patients than that of controls. Conclusion: We, however, have a small sample size, and this test requires the subject cooperation. In addition the stroke types of the patients are heterogeneous. Nevertheless, our results suggest that unilateral cerebrovascular ischemic insult can affect blood flow in both MCAs in patients with acute ischemic events in the MCA territory.