Regional cerebral blood flow in chronic hypertension. A correlative study.

Abstract

Background and Purpose: Cerebral hypoperfusion has occasionally been reported during essential hypertension. We explored regional cerebral blood flow in a large series of neurologically asymptomatic hypertensive patients to determine relations among cerebral blood flow, concomitant main vascular risk factors, and the most common signs of end-organ damage.Methods: Regional cerebral blood flow was measured by the`33Xe inhalation method in 101 hypertensive patients without clinically apparent central nervous system involvement, including 39 mild to moderate untreated and 62 mild to severe treated patients.Results: Compared with age-and sex-matched normal control subjects, cerebral blood flow was significantly reduced in untreated hypertensive patients (P<.01) and to a lesser extent in treated patients (P=.047). Both regional and global cerebral blood flow reductions were observed in approximately one third of patients in both groups. Analysis of variance failed to show significant correlations between cerebral blood flow and total cholesterol concentration, mean arterial blood pressure, duration of disease, or the presence of retinopathy or left ventricular hypertrophy. In the treated group, the quality of control of hypertension significantly influenced both global cerebral blood flow (P=.007) and cerebrovascular resistance (P<.0001).Conclusions: Focal or diffuse cerebral hypoperfusion is present even in neurologically asymptomatic hypertensive patients, especially when untreated; good control of blood pressure may preserve cerebral

Regional Cerebral Blood Flow and Arterial Blood Volume and Their Reactivity to Hypercapnia in Hypertensive and Normotensive Rats

“…29 We also observed a similar baseline CBF in SHR and WKY animals, consistent with some human studies 1,11-14 but not others in which hypertensive subjects demonstrated a slight reduction in CBF. [8][9][10] At the same time, in other studies using the SHR and WKY models, hypertensive animals had a much higher baseline CBF value than control animals under 2% isoflurane (104 ± 23 versus 71±19 mL/100 g per minute 30 and 150±20 versus120±20 mL/ 100 g per minute. 31 ) However, the fact that we used B1% isoflurane while the other studies used 2% may account for this difference in results.…”

“…These cerebrovascular alterations could eventually lead to a regional reduction in cerebral blood flow (CBF) and tissue oxygenation, [3][4][5] thereby increasing the risk of stroke, vascular dementia, and cognitive decline. [6][7][8] However, early-stage alterations in the cerebrovasculature are easily modified. As the cerebral regulation of blood pressure differs from the systemic regulation, treatment aimed at reducing peripheral blood pressure may not provide the necessary therapy to prevent impairments of the brain vasculature.…”

“…Hypertension-induced alterations in CBF have been assessed by magnetic resonance imaging (MRI), single-photon emission computed tomography and positron emission tomography, which reported a slight reduction in baseline (normocapnic) CBF in some, [8][9][10] but not in all hypertensive subjects. 1,[11][12][13][14] In addition, studies showed that, as compared with normotensive subjects, hypertensive subjects have a blunted CBF response to neural tasks 11 and CO 2 stimulus.…”

Alcohol consumption and cerebral blood flow among older adults

“…Candidate covariates were selected based on literature review of variables impacting CBF as well as exploratory analyses. Specifically, previous studies have identified relationships between CBF and age (Kubota et al, 1983;Naritomi et al, 1979), gender (Gur et al, 1982), and intima-media thickness (Claus et al, 1996;Nobili et al, 1993). Systolic and diastolic blood pressure, body mass index (BMI), and smoking status were also examined as potential covariates.…”

Are Alzheimer’s disease, hypertension, and cerebrocapillary damage related?☆

“…Besides such systemic damage, abnormally high pressure can also threaten an optimal cerebral blood supply, as it was show in hypertensive individuals. When the CBF of hypertensive patients was measured with PET or the 133ϫe-inhalation method, and the data compared to those of normotensive individuals, reduced flow rate was recorded in the hypertensive patients [21,37,39]. In addition, the drop in CBF was less pronounced in high blood pressure patients who were receiving an anti-hypertensive treatment [39].…”