Abstract:
OBJECTIVE:Increased penetration of pulsatile power to the brain has been implicated in the pathogenesis of age-related cognitive dysfunction and dementia, a common comorbidity in patients with heart failure and preserved ejection fraction (HFpEF). However, there is a lack of knowledge on the effects of organic and inorganic nitrates administration in this population on the power carried by pressure and flow waves traveling through the proximal aorta and penetrating the carotid artery into the brain microvasculature. APPROACH:We assessed aortic and carotid hemodynamics non-invasively in two sub-studies: (1) at baseline and after administration of 0.4 mg of sublingual nitroglycerine (an organic nitrate; n = 26); and (2) in a randomized controlled trial of placebo (PB) versus inorganic nitrate administration (beetroot-juice (BR), 12.9 mmol NO3; n = 16). MAIN RESULTS:Wave and hydraulic power analysis demonstrated that NTG increased total hydraulic power (from 5.68% at baseline to 8.62%, P = 0.001) and energy penetration (from 8.69% to 11.63%; P = 0.01) from the aorta to the carotid, while inorganic nitrate administration did not induce significant changes in aortic and carotid wave power (power: 5.49%PB versus 6.25%BR, P = 0.49; energy: 8.89%PB versus 10.65%BR, P = 0.27). SIGNIFICANCE:Organic nitrates, but not inorganic nitrates, increase the amount of hydraulic energy transmitted into the carotid artery in subjects with HFpEF. These findings may have implications for the adverse effect profiles of these agents (such as the differential incidence of headaches) and for the pulsatile hemodynamic stress of the brain microvasculature in this patient population.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Londono-Hoyos F,Zamani P,Beraun M,Vasim I,Segers P,Chirinos JAdoi
10.1088/1361-6579/aab2efsubject
Has Abstractpub_date
2018-04-20 00:00:00pages
044001issue
4eissn
0967-3334issn
1361-6579journal_volume
39pub_type
杂志文章,随机对照试验abstract::A method was developed for simultaneously measuring plasma resistance, cell interior resistance and cell membrane capacitance of blood. A three-element circuit model for simulating the impedance of blood was evaluated by comparing measured and calculated impedance frequency curves and was found feasible. The values of...
journal_title:Physiological measurement
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journal_title:Physiological measurement
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journal_title:Physiological measurement
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abstract::Skinfold anthropometry is a widely practiced technique often with little appreciation of its limitations. The large residual error appearing in any regressions of body density versus sums of skinfolds is primarily due to biological causes, in particular the non-constancy of the ratio of subcutaneous to total body fat....
journal_title:Physiological measurement
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journal_title:Physiological measurement
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pub_type: 杂志文章,评审
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journal_title:Physiological measurement
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pub_type: 杂志文章
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journal_title:Physiological measurement
pub_type: 杂志文章
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journal_title:Physiological measurement
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doi:10.1088/0967-3334/27/6/005
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journal_title:Physiological measurement
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journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
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journal_title:Physiological measurement
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journal_title:Physiological measurement
pub_type: 杂志文章
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