Arterial pressure and cerebral blood flow variability: friend or foe? A review

Rickards, Caroline A.; Tzeng, Yu‐Chieh

doi:10.3389/fphys.2014.00120

Cited by 69 publications

(64 citation statements)

References 116 publications

(164 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…). In response to dynamic changes in BP, cerebrovascular bed behaves as a ‘high‐pass filter’ system, which buffers the effects of BP fluctuations on CBF via cerebral autoregulation (CA) (Lassen ; Rickards and Tzeng ). The CA is more or less a frequency dependent phenomenon that operates more efficiently at very low frequency (< 0.05 Hz) (Aaslid et al .…”

Section: Main Determinants Of Cbfmentioning

confidence: 99%

Cerebral blood flow in normal aging adults: cardiovascular determinants, clinical implications, and aerobic fitness

Tarumi

Zhang

2017

Journal of Neurochemistry

213

142

View full text Add to dashboard Cite

Senescence is a leading cause of mortality, disability, and noncommunicable chronic diseases in older adults. Mounting evidence indicates that the presence of cardiovascular disease and risk factors elevates the incidence of both vascular cognitive impairment and Alzheimer's disease (AD). Age-related declines in cardiovascular function may impair cerebral blood flow (CBF) regulation, leading to the disruption of neuronal micro-environmental homeostasis. The brain is the most metabolically active organ with limited intracellular energy storage and critically depends on CBF to sustain neuronal metabolism. In patients with AD, cerebral hypoperfusion, increased CBF pulsatility, and impaired blood pressure control during orthostatic stress have been reported, indicating exaggerated, age-related decline in both cerebro-and cardiovascular function. Currently, AD lacks effective treatments; therefore, the development of preventive strategy is urgently needed. Regular aerobic exercise improves cardiovascular function, which in turn may lead to a better CBF regulation, thus reducing the dementia risk. In this review, we discuss the effects of aging on cardiovascular regulation of CBF and provide new insights into the vascular mechanisms of cognitive impairment and potential effects of aerobic exercise training on CBF regulation.

show abstract

Section: Main Determinants Of Cbfmentioning

confidence: 99%

Cerebral blood flow in normal aging adults: cardiovascular determinants, clinical implications, and aerobic fitness

Tarumi

Zhang

2017

Journal of Neurochemistry

213

142

View full text Add to dashboard Cite

show abstract

“…Interest in biological variability has exploded over the past decade, with significant literature now focusing on neural (Wang, 2010) and cardiovascular (Lehrer and Eddie, 2013; Rickards and Tzeng, 2014) oscillations. Greater variability in biological functions is generally thought to demonstrate more intact regulatory systems that are appropriately detecting and dynamically responding to perturbation (Kitano, 2004; Lehrer and Eddie, 2013; Thayer and Lane, 2000).…”

mentioning

confidence: 99%

“…Rather, it can flexibly respond to challenge by changing stroke volume, vascular tone, and blood pressure (BP) variability in addition to or in lieu of changing HRV (Liu et al, 2004; Ma and Zhang, 2006; Rickards and Tzeng, 2014; Vaschillo et al, 2012). System redundancy ensures that the cardiovascular system can buffer itself against internal (e.g., cognitive emotional) and external (e.g., pharmacological) challenges, and thus protect the brain from stroke and the heart from myocardial infarction.…”

mentioning

confidence: 99%

Immediate and Complex Cardiovascular Adaptation to an Acute Alcohol Dose

Buckman

Eddie

Vaschillo

et al. 2015

Alcoholism Clin & Exp Res

View full text Add to dashboard Cite

Background The detrimental effects of chronic heavy alcohol use on the cardiovascular system are well established and broadly appreciated. Integrated cardiovascular response to an acute dose of alcohol has been less studied. This study examined the early effects of an acute dose of alcohol on the cardiovascular system, with particular emphasis on system variability and sensitivity. The goal was to begin to understand how acute alcohol disrupts dynamic cardiovascular regulatory processes prior to the development of cardiovascular disease. Methods Healthy participants (N = 72, age 21 to 29) were randomly assigned to an alcohol, placebo, or no-alcohol control beverage condition. Beat-to-beat heart rate (HR) and blood pressure (BP) were assessed during a low-demand cognitive task prior to and following beverage consumption. Between-group differences in neurocardiac response to an alcohol challenge (blood alcohol concentration ~ 0.06 mg/dl) were tested. Results The alcohol beverage group showed higher average HR, lower average stroke volume, lower HR variability and BP variability, and increased vascular tone baroreflex sensitivity after alcohol consumption. No changes were observed in the placebo group, but the control group showed slightly elevated average HR and BP after beverage consumption, possibly due to juice content. At the level of the individual, an active alcohol dose appeared to disrupt the typically tight coupling between cardiovascular processes. Conclusions A dose of alcohol quickly invoked multiple cardiovascular responses, possibly as an adaptive reaction to the acute pharmacological challenge. Future studies should assess how exposure to alcohol acutely disrupts or dissociates typically integrated neurocardiac functions.

show abstract

“…). However, more recently Rickards and Tzeng () reviewed the role of oscillations in MAP and MCAv during hemorrhage and concluded that increased variability may protect cerebral blood flow during hypovolemia. The underlying mechanism may be that less energy is required to maintain forward flow if the flow is pulsatile versus continuous.…”

Section: Discussionmentioning

confidence: 99%

Effect of acute hypoxemia on cerebral blood flow velocity control during lower body negative pressure

et al. 2018

View full text Add to dashboard Cite

The ability to maintain adequate cerebral blood flow and oxygenation determines tolerance to central hypovolemia. We tested the hypothesis that acute hypoxemia during simulated blood loss in humans would cause impairments in cerebral blood flow control. Ten healthy subjects (32 ± 6 years, BMI 27 ± 2 kg·m−2) were exposed to stepwise lower body negative pressure (LBNP, 5 min at 0, −15, −30, and −45 mmHg) during both normoxia and hypoxia (FiO2 = 0.12–0.15 O2 titrated to an SaO2 of ~85%). Physiological responses during both protocols were expressed as absolute changes from baseline, one subject was excluded from analysis due to presyncope during the first stage of LBNP during hypoxia. LBNP induced greater reductions in mean arterial pressure during hypoxia versus normoxia (MAP, at −45 mmHg: −20 ± 3 vs. −5 ± 3 mmHg, P < 0.01). Despite differences in MAP, middle cerebral artery velocity responses (MCAv) were similar between protocols (P = 0.41) due to increased cerebrovascular conductance index (CVCi) during hypoxia (main effect, P = 0.04). Low frequency MAP (at −45 mmHg: 17 ± 5 vs. 0 ± 5 mmHg2, P = 0.01) and MCAv (at −45 mmHg: 4 ± 2 vs. −1 ± 1 cm·s−2, P = 0.04) spectral power density, as well as low frequency MAP‐mean MCAv transfer function gain (at −30 mmHg: 0.09 ± 0.06 vs. −0.07 ± 0.06 cm·s−1·mmHg−1, P = 0.04) increased more during hypoxia versus normoxia. Contrary to our hypothesis, these findings support the notion that cerebral blood flow control is not impaired during exposure to acute hypoxia and progressive central hypovolemia despite lower MAP as a result of compensated increases in cerebral conductance and flow variability.

show abstract

Arterial pressure and cerebral blood flow variability: friend or foe? A review

Cited by 69 publications

References 116 publications

Cerebral blood flow in normal aging adults: cardiovascular determinants, clinical implications, and aerobic fitness

Cerebral blood flow in normal aging adults: cardiovascular determinants, clinical implications, and aerobic fitness

Immediate and Complex Cardiovascular Adaptation to an Acute Alcohol Dose

Effect of acute hypoxemia on cerebral blood flow velocity control during lower body negative pressure

Contact Info

Product

Resources

About