Matches in SemOpenAlex for { <https://semopenalex.org/work/W2024974442> ?p ?o ?g. }
Showing items 1 to 45 of
45
with 100 items per page.
- W2024974442 abstract "HomeStrokeVol. 41, No. 5Response to Letter by Tzeng et al Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBResponse to Letter by Tzeng et al Marek Sykora, MD, PhD Jennifer Diedler, MD and Thorsten Steiner, MD Marek SykoraMarek Sykora Department of Neurology, University of Heidelberg, Heidelberg, Germany, Department of Neurology, Comenius University, Bratislava, Slovakia Search for more papers by this author Jennifer DiedlerJennifer Diedler Department of Neurology, University of Heidelberg, Heidelberg, Germany Search for more papers by this author and Thorsten SteinerThorsten Steiner Department of Neurology, University of Heidelberg, Heidelberg, Germany Search for more papers by this author Originally published1 Apr 2010https://doi.org/10.1161/STROKEAHA.109.572206Stroke. 2010;41:e430Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: April 1, 2010: Previous Version 1 Response:We thank Tzeng et al for their very interesting comments on the new evidence for interactions between cerebrovascular autoregulation (CA) and the arterial baroreflex system. As stated by the authors, studies focusing on this association are only emerging, thus the evidence is rather limited at this time. Nevertheless, we agree on the hypothesis that the autonomic nervous system, including the baroreflex, plays an important role in regulating cerebral blood flow (CBF), presumably also integrating changes in the dynamic CA.1–3Tzeng et al report a positive correlation between baroreflex sensitivity (BRS) and arterial blood pressure variability. This is in line with our observation that decreased BRS was associated with increased blood pressure variability in stroke patients, possibly contributing to the occurrence of hypertensive crises in the acute phase (M. Sykora, et al, unpublished data, 2010).4 They suggest an inverse correlation between dynamic CA and BRS, implicating possible adjustment of the dynamic CA for the demands of altered BRS with increased blood pressure variability. Interestingly, we have observed a possibly related, albeit opposite, phenomenon examining BRS in neurocritical care patients experiencing raised intracranial pressure (ICP). In patients with ICP levels impairing the functioning of dynamic CA, we found baroreflex hypersensitivity followed by blood pressure elevations, putatively targeting the restoration of normal CBF (M. Sykora, et al, unpublished data, 2010). The BRS correlated strongly and positively with ICP levels. Increased ICP has been shown to shift upward the lower limit of CBF autoregulation, implicating that the compensation for an acute increase in ICP with an equal increase in arterial blood pressure may not be sufficient to keep the CBF constant.5 We suggest that under these circumstances, the baroreflex system resets its sensitivity to compensate for the impaired CA. This consideration would be in line with the observations mentioned by Tzeng et al on inverse correlation between BRS and CA. Our finding may further support the “cross-linked” hypothesis that CA and BRS (autonomic drive) are a part of the same regulatory continuum.6The pathophysiological reaction of raised ICP followed by hypertension and heart rate decline is clinically known as the Cushing reflex. It is thought to be a preterminal phenomenon accompanying cerebral lesions with mass effect. Indeed, this reflex becomes clinically manifest only at very high ICP levels. However, we observed baroreflex hypersensitivity, which may be considered as the mechanisms behind the Cushing response, also in patients with moderately elevated ICP with no clinical signs of hypertension and bradycardia (M. Sykora, et al, unpublished data, 2010). Here again, we hypothesize an underlying shift in the BRS, serving to adjust the CBF for states of altered CA or raised ICP. This implicates that the intracranial component of the baroreflex system may be regarded as a neuroprotective mechanism.Thus, the interplay between arterial baroreflex and CA seems to have a crucial role in CBF regulation under normal and pathological conditions. However, the complex relationship between BRS and CA and its clinical implications remain to be elucidated more in detail in future studies.DisclosuresNone.1 Zhang R, Zuckerman JH, Iwasaki K, Wilson TE, Crandall CG, Levine BD. Autonomic neural control of dynamic cerebral autoregulation in humans. Circulation. 2002; 106: 1814–1820.LinkGoogle Scholar2 Ogoh S, Brothers RM, Eubank WL, Raven PB. Autonomic neural control of the cerebral vasculature: acute hypotension. Stroke. 2008; 39: 1979–1987.LinkGoogle Scholar3 Lavinio A, Ene-Iordache B, Nodari I, Girardini A, Cagnazzi E, Rasulo F, Smielewski P, Czosnyka M, Latronico N. Cerebrovascular reactivity and autonomic drive following traumatic brain injury. Acta Neurochir Suppl. 2008; 102: 3–7.CrossrefMedlineGoogle Scholar4 Sykora M, Diedler J, Turcani P, Rupp A, Steiner T. Subacute perihematomal edema in intracerebral hemorrhage is associated with impaired blood pressure regulation. J Neurol Sci. 2009; 284: 108–112.CrossrefMedlineGoogle Scholar5 Brady KM, Lee JK, Kibler KK, Easley RB, Koehler RC, Czosnyka M, Smielewski P, Shaffner DH. The lower limit of cerebral blood flow autoregulation is increased with elevated intracranial pressure. Anesth Analg. 2009; 108: 1278–1283.CrossrefMedlineGoogle Scholar6 Sykora M, Diedler J, Turcani P, Hacke W, Steiner T. Baroreflex: a new therapeutic target in human stroke? Stroke. 2009; 40: e678–e682.LinkGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetails May 2010Vol 41, Issue 5 Advertisement Article InformationMetrics https://doi.org/10.1161/STROKEAHA.109.572206 Originally publishedApril 1, 2010 PDF download Advertisement" @default.
- W2024974442 created "2016-06-24" @default.
- W2024974442 creator A5005655779 @default.
- W2024974442 creator A5048743789 @default.
- W2024974442 creator A5066759572 @default.
- W2024974442 date "2010-05-01" @default.
- W2024974442 modified "2023-10-16" @default.
- W2024974442 title "Response to Letter by Tzeng et al" @default.
- W2024974442 cites W194042569 @default.
- W2024974442 cites W2008573332 @default.
- W2024974442 cites W2039440705 @default.
- W2024974442 cites W2073361138 @default.
- W2024974442 cites W2095800632 @default.
- W2024974442 cites W2143987433 @default.
- W2024974442 doi "https://doi.org/10.1161/strokeaha.109.572206" @default.
- W2024974442 hasPublicationYear "2010" @default.
- W2024974442 type Work @default.
- W2024974442 sameAs 2024974442 @default.
- W2024974442 citedByCount "0" @default.
- W2024974442 crossrefType "journal-article" @default.
- W2024974442 hasAuthorship W2024974442A5005655779 @default.
- W2024974442 hasAuthorship W2024974442A5048743789 @default.
- W2024974442 hasAuthorship W2024974442A5066759572 @default.
- W2024974442 hasBestOaLocation W20249744421 @default.
- W2024974442 hasConcept C71924100 @default.
- W2024974442 hasConceptScore W2024974442C71924100 @default.
- W2024974442 hasIssue "5" @default.
- W2024974442 hasLocation W20249744421 @default.
- W2024974442 hasOpenAccess W2024974442 @default.
- W2024974442 hasPrimaryLocation W20249744421 @default.
- W2024974442 hasRelatedWork W1506200166 @default.
- W2024974442 hasRelatedWork W2039318446 @default.
- W2024974442 hasRelatedWork W2048182022 @default.
- W2024974442 hasRelatedWork W2080531066 @default.
- W2024974442 hasRelatedWork W2604872355 @default.
- W2024974442 hasRelatedWork W2748952813 @default.
- W2024974442 hasRelatedWork W2899084033 @default.
- W2024974442 hasRelatedWork W2998699411 @default.
- W2024974442 hasRelatedWork W3032375762 @default.
- W2024974442 hasRelatedWork W3108674512 @default.
- W2024974442 hasVolume "41" @default.
- W2024974442 isParatext "false" @default.
- W2024974442 isRetracted "false" @default.
- W2024974442 magId "2024974442" @default.
- W2024974442 workType "article" @default.