| Calculation of mean arterial pressure during exercise as a function of heart rate. | |
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MedLine Citation:
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PMID: 8591100 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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Mean arterial blood pressure (MAP) is a common characteristic of the cardiac cycle. Usually it is evaluated by assuming that the left ventricular ejection time (systole) constitutes a constant proportion of the cardiac cycle (i.e. 1/3), regardless of the heart rate (HR). However, elevation of HR during exercise results in a reduction of the duration of the ejection period and even a greater reduction of the ventricular filling period. Therefore, a constant diastole/systole proportion at various heart rates may be misleading. The purpose of this study was therefore to evaluate the accurate proportion of the systolic period from the cardiac cycle at different metabolic rates and calculate MAP accordingly. Twenty healthy subjects (age: 20-50 yr.) exercised at different work intensities on a cycle ergometer to elicit HR in the range of 55-180 bpm. During the ride the mitral and aortic flow velocity wave form were recorded by Doppler echocardiography; the mitral flow from the apical view and the aortic flow from the apical long axis view. Blood pressure was measured using a sphygmomanometer. The fraction of systole (St) from the heart cycle was related to HR and was described in mathematical terms as: St = 0.01exp(4.14-40.74/HR) MAP was then calculated from the diastolic blood pressure (dBP) and the pulse pressure (PP) adjusted for St as follows: MAP = dBP+St.PP; (mmHg) The use of the suggested model reduces errors in the evaluation of various cardiac parameters which are related to arterial pressure, such as peripheral resistance, especially under exercise-heat stress. |
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Authors:
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D Moran; Y Epstein; G Keren; A Laor; J Sherez; Y Shapiro |
Publication Detail:
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Type: Clinical Trial; Journal Article |
Journal Detail:
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Title: Applied human science : journal of physiological anthropology Volume: 14 ISSN: 1341-3473 ISO Abbreviation: Appl Human Sci Publication Date: 1995 Nov |
Date Detail:
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Created Date: 1996-04-01 Completed Date: 1996-04-01 Revised Date: 2004-11-17 |
Medline Journal Info:
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Nlm Unique ID: 9506216 Medline TA: Appl Human Sci Country: JAPAN |
Other Details:
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Languages: eng Pagination: 293-5 Citation Subset: IM; S |
Affiliation:
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Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Adult Blood Pressure* Exercise / physiology* Female Heart Rate* Humans Mathematics Middle Aged Models, Cardiovascular |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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