Circadian variation of arterial pressure wave reflections

Papaioannou, TG; Karatzis, EN; Papamichael, CM; Karatzi, KN; Zakopoulos, NA; Lekakis, JP; Stefanadis, C

dc.contributor.author	Papaioannou, TG	en
dc.contributor.author	Karatzis, EN	en
dc.contributor.author	Papamichael, CM	en
dc.contributor.author	Karatzi, KN	en
dc.contributor.author	Zakopoulos, NA	en
dc.contributor.author	Lekakis, JP	en
dc.contributor.author	Stefanadis, C	en
dc.date.accessioned	2014-03-01T01:55:30Z
dc.date.available	2014-03-01T01:55:30Z
dc.date.issued	2006	en
dc.identifier.issn	0895-7061	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/27772
dc.subject	wave reflections	en
dc.subject	arterial stiffness	en
dc.subject	augmentation index	en
dc.subject	circadian pattern	en
dc.subject	rhythm	en
dc.subject	variability	en
dc.subject.classification	Peripheral Vascular Disease	en
dc.subject.other	BLOOD-PRESSURE	en
dc.subject.other	APPLANATION TONOMETRY	en
dc.subject.other	CARDIAC ARRESTS	en
dc.subject.other	STIFFNESS	en
dc.subject.other	HUMANS	en
dc.subject.other	HYPERTENSION	en
dc.subject.other	FREQUENCY	en
dc.subject.other	CAFFEINE	en
dc.subject.other	EVENTS	en
dc.subject.other	ONSET	en
dc.title	Circadian variation of arterial pressure wave reflections	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	Background: Various factors are implicated in the circadian pattern of cardiovascular vulnerability. The exact mechanisms involved in the peak incidence of cardiovascular events occurring during the early morning hours after awaking are not completely known. The purpose of our study was to investigate the circadian variation of timing and intensity of wave reflections in healthy individuals and to test the hypothesis that significant changes occur during the day. Methods: Thirteen healthy non-smokers (seven women and six men, mean age 40.7 +/- 16.5 years) were examined. Aortic pulse wave analysis was performed to estimate surrogates of wave reflections intensity (augmentation index [AIx]) and timing. Twelve measurements separated by 1-h intervals were performed from 8 AM to 7 Pm each study day. Results: Analysis of variance for repeated measures significant changes during the 12-h period for heart rate corrected AIx (P =.033) and heart rate (P = .035). The AIx was maximal at 8 AM within 1-h after awaking (17% +/- 3.6%); it was gradually diminished until 3 PM (9% +/- 4.1%) and again increased to a second (albeit lower) peak value during the late afternoon (7 PM). Conclusions: It is possible that the increased intensity of reflected waves occurring during the early morning in combination with the rising trend of blood pressure and heart rate at the same time results in an aggravated left ventricular afterload and an increase in myocardial oxygen demand. The morning-related enhancement of wave reflections may have potential implications for the increased risk for cardiovascular events during the early morning, which remains to be clarified.	en
heal.publisher	ELSEVIER SCIENCE INC	en
heal.journalName	AMERICAN JOURNAL OF HYPERTENSION	en
dc.identifier.isi	ISI:000235984400004	en
dc.identifier.volume	19	en
dc.identifier.issue	3	en
dc.identifier.spage	259	en
dc.identifier.epage	263	en