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Pericardial-mediated diastolic ventricular interactions in endurance-trained athletes during orthostatic stress Esch, Ben Thomas Alexander.
Abstract
Purpose: To assess diastolic ventricular interaction (DVI) and its consequences in endurance athletes and normally active individuals during lower body positive (LBPP) and negative pressure (LBNP). Methods: Eight male endurance athletes (VO₂ max 65.4 ± 5.7 mL•kg⁻¹•min⁻¹) and eight normally active individuals (VO₂ max 45.1 ± 6.0 mL•kg⁻¹•min⁻¹) underwent three experimental days: 1) assessment of VO₂ max 2) a negative orthostatic tolerance test, and 3) LBPP (0 to 60 mmHg) and LBNP (0 to -80 mmHg) during which time ventricular volumes were examined via echocardiography. Results: All normally active individuals completed the tolerance test on experimental day two, but seven out of eight athletes did not complete this test due to signs of presyncope. There were no statistically significant differences between groups in resting left ventricular end-diastolic volume (LVEDV), stroke volume, or cardiac output. In response to LBNP on experimental day three there was a similar decrease in right ventricular (RV) end-diastolic area in both groups. However, there was a differential group response to LBNP (a greater decrease in the endurance athletes) during day three with respect to LVEDV (p<0.05). The endurance athletes also had significantly greater decreases in stroke volume and cardiac output during LBNP compared to the normally active group (p<0.05). During LBPP on day three, the endurance athletes showed greater increases in LVEDV and stroke volume, despite similar responses in RV end diastolic area (p<0.05). Conclusion: Endurance athletes likely had a relatively slack pericardium causing minimized DVI during conditions of orthostatic stress, whereas the normally active individuals appear to have more marked DVI during orthostatic stress which allows for a paradoxically greater maintenance of LV filling in response to LBNP.
Item Metadata
Title |
Pericardial-mediated diastolic ventricular interactions in endurance-trained athletes during orthostatic stress
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Creator | |
Publisher |
University of British Columbia
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Date Issued |
2005
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Description |
Purpose: To assess diastolic ventricular interaction (DVI) and its consequences in
endurance athletes and normally active individuals during lower body positive (LBPP)
and negative pressure (LBNP).
Methods: Eight male endurance athletes (VO₂ max 65.4 ± 5.7 mL•kg⁻¹•min⁻¹) and eight
normally active individuals (VO₂ max 45.1 ± 6.0 mL•kg⁻¹•min⁻¹) underwent three
experimental days: 1) assessment of VO₂ max 2) a negative orthostatic tolerance test, and
3) LBPP (0 to 60 mmHg) and LBNP (0 to -80 mmHg) during which time ventricular
volumes were examined via echocardiography.
Results: All normally active individuals completed the tolerance test on experimental day
two, but seven out of eight athletes did not complete this test due to signs of presyncope.
There were no statistically significant differences between groups in resting left
ventricular end-diastolic volume (LVEDV), stroke volume, or cardiac output. In
response to LBNP on experimental day three there was a similar decrease in right
ventricular (RV) end-diastolic area in both groups. However, there was a differential
group response to LBNP (a greater decrease in the endurance athletes) during day three
with respect to LVEDV (p<0.05). The endurance athletes also had significantly greater
decreases in stroke volume and cardiac output during LBNP compared to the normally
active group (p<0.05). During LBPP on day three, the endurance athletes showed greater
increases in LVEDV and stroke volume, despite similar responses in RV end diastolic
area (p<0.05).
Conclusion: Endurance athletes likely had a relatively slack pericardium causing
minimized DVI during conditions of orthostatic stress, whereas the normally active individuals appear to have more marked DVI during orthostatic stress which allows for a
paradoxically greater maintenance of LV filling in response to LBNP.
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Genre | |
Type | |
Language |
eng
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Date Available |
2009-12-15
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Provider |
Vancouver : University of British Columbia Library
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Rights |
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
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DOI |
10.14288/1.0077034
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URI | |
Degree | |
Program | |
Affiliation | |
Degree Grantor |
University of British Columbia
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Graduation Date |
2005-11
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Campus | |
Scholarly Level |
Graduate
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Aggregated Source Repository |
DSpace
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Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.