Steady State vs. Pulsatile Blood Pressure Component and Regional Cerebral Perfusion

BACKGROUND: Arterial blood pressure (BP) can be divided into steady state component that is determined by mean arterial pressure and pulsatile component that is explored by pulse pressure (PP). We determined relationships between BP components and regional cerebral perfusion. METHODS: A total of 52 apparently healthy and cognitively normal adults aged 40-60 years were studied. Regional cerebral perfusion was measured using functional magnetic resonance imaging (MRI) arterial spin labeling technique in 10 a priori regions of interest. RESULTS: There were 5 regions with cerebral perfusion values significantly associated with either pulsatile BP component (i.e., hippocampus, posterior insula, and central white matter) or both steady and pulsatile components (i.e., anterior white matter, and occipitoparietal area). After controlling for body mass index, education, age, and sex, associations between pulsatile BP components and regional cerebral perfusion remained significant in 2 regions (i.e., hippocampus and anterior white matter). Multiple linear regression analyses revealed that brachial systolic pressure (β = -0.35, P = 0.03) and PP (β = -0.36, P = 0.02) explained 11 and 12% of the variability in hippocampus perfusion, independent of the entered covariates. CONCLUSIONS: The present preliminary study indicated that pulsatile component of BP was more strongly related to regional cerebral perfusion in areas susceptible to cerebrovascular diseases than steady state component.