Abstract:
BACKGROUND:Sensitization of mechanosensitive afferents, which contribute to the exercise pressor reflex, has been recognized as a characteristic of patients with heart failure (HF); however, the hemodynamic implications of this hypersensitivity are unclear. OBJECTIVES:The present study used passive leg movement (PLM) and intrathecal injection of fentanyl to blunt the afferent portion of this reflex arc to better understand the role of the mechanoreflex on central and peripheral hemodynamics in HF. METHODS:Femoral blood flow (FBF), mean arterial pressure, femoral vascular conductance, HR, stroke volume, cardiac output, ventilation, and muscle oxygenation of the vastus lateralis were assessed in 10 patients with New York Heart Association class II HF at baseline and during 3 min of PLM both with fentanyl and without (control). RESULTS:Fentanyl had no effect on baseline measures but increased (control vs fentanyl, P < 0.05) the peak PLM-induced change in FBF (493 ± 155 vs 804 ± 198 ΔmL·min(-1)) and femoral vascular conductance (4.7 ± 2 vs 8.5 ± 3 ΔmL·min(-1)·mm Hg)(-1) while norepinephrine spillover (103% ± 19% vs 58% ± 17%Δ) and retrograde FBF (371 ± 115 vs 260 ± 68 ΔmL·min(-1)) tended to be reduced (P < 0.10). In addition, fentanyl administration resulted in greater PLM-induced increases in muscle oxygenation, suggestive of increased microvascular perfusion. Fentanyl had no effect on the ventilation, mean arterial pressure, HR, stroke volume, or cardiac output response to PLM. CONCLUSIONS:Although movement-induced central hemodynamics were unchanged by afferent blockade, peripheral hemodynamic responses were significantly enhanced. Thus, in patients with HF, a heightened mechanoreflex seems to augment peripheral sympathetic vasoconstriction in response to movement, a phenomenon that may contribute to exercise intolerance in this population.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Ives SJ,Amann M,Venturelli M,Witman MA,Groot HJ,Wray DW,Morgan DE,Stehlik J,Richardson RSdoi
10.1249/MSS.0000000000000782subject
Has Abstractpub_date
2016-03-01 00:00:00pages
368-76issue
3eissn
0195-9131issn
1530-0315journal_volume
48pub_type
杂志文章abstract::The 1-mile run/walk test is the field test of choice for evaluating maximal aerobic power (VO2max) in school-aged children. The objective of this study was to determine the relative importance of selected metabolic determinants of mile run/walk performance in children 6-14 yr of age. Mile run/walk time (MRWT), VO2max,...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1991-05-01 00:00:00
abstract:UNLABELLED:Physically active classroom lessons have been found to increase on-task behavior in children. Given that physical activity has been associated with an increased time on task (TOT) and that overweight children take fewer steps than normal weight children do, it was expected that benefits of the physical activ...
journal_title:Medicine and science in sports and exercise
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doi:10.1249/MSS.0b013e3181a61495
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journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
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更新日期:1990-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:Medicine and science in sports and exercise
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更新日期:1995-11-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31817f36f9
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journal_title:Medicine and science in sports and exercise
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doi:
更新日期:1991-09-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章
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更新日期:2003-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1990-04-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
doi:
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
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journal_title:Medicine and science in sports and exercise
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更新日期:1995-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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更新日期:1997-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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doi:
更新日期:1988-12-01 00:00:00
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pub_type: 杂志文章,随机对照试验
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更新日期:2006-10-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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更新日期:2020-08-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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