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- Hansen, F, et al.
(författare)
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Non-invasive measurement of pulsatile vessel diameter change and elastic properties in human arteries: a methodological study
- 1993
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Ingår i: Clinical Physiology. - 1365-2281. ; 13:6, s. 631-643
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Tidskriftsartikel (refereegranskat)abstract
- A recently developed ultrasound phase-locked echo-tracking system makes it possible to measure non-invasive pulsatile vessel diameter changes, and, in combination with blood-pressure measurement, to calculate pressure strain elastic modulus (Ep) and stiffness (beta). The reproducibility in measurements of pulsatile diameter changes with this system was evaluated. Also the precision of indirect blood-pressure measurements, as compared to the simultaneously measured intra-arterial blood pressure was tested. The resulting reproducibility in pressure strain elastic modulus (Ep) and stiffness (beta) was evaluated. Intra-observer variabilities in measuring pulsatile diameter changes were 16% for the abdominal aorta, 10% for the common carotid artery, and 15% for the common femoral artery, respectively. Intra-observer variabilities for Ep and beta were 21% for both in the abdominal aorta, 17% for both in the common carotid artery, and 18% for both in the common femoral artery, respectively. There were only small differences in indirect and direct measurement of systolic blood pressure, whereas indirect blood pressure measurement systematically overestimated the diastolic blood pressure, on average by 20%. The variabilities in indirect blood pressure measurements were 2% for the systolic and 3% for the diastolic blood pressure, respectively. Inter-observer variability in the investigation of the common carotid artery was 10% for the pulsatile diameter changes, and 21% and 23% for Ep and beta, respectively. Thus, the echo-tracking system represents a reliable system for estimation of pressure strain elastic modulus and stiffness. However, Ep and beta are systematically underestimated by 25-30%, when used in combination with indirect blood pressure measurements.
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| 2. |
- Lanne, T, et al.
(författare)
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Differences in mechanical properties of the common carotid artery and abdominal aorta in healthy males
- 1994
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Ingår i: Journal of Vascular Surgery. - 1097-6809. ; 20:2, s. 218-225
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Vascular disease is differentiated throughout the vascular regions, with central arteries more prone to dilation and with peripheral arteries more prone to occlusive disease. In this study we investigated the diameter and compliance in the common carotid artery and abdominal aorta in healthy males at varying ages to assess potential differences in the aging process. METHODS: An ultrasound phase-locked echo-tracking system was used to determine differences in diameter and pulsatile diameter changes of the common carotid artery and abdominal aorta in 56 healthy Caucasian males ages 10 to 74 years. Pressure strain elastic modulus (Ep) and stiffness (beta) were calculated from diameter, pulsatile diameter change, and blood pressure obtained by the auscultatory method. Compliance was defined as the inverse of Ep and stiffness. RESULTS: The diameter of both common carotid artery and abdominal aorta increases not only when a person is a child, but also when they are between 25 and 70 years old. The dilation in adults seems to be more accentuated in the abdominal aorta (27%) than in the common carotid artery (17%). Ep and stiffness (beta) are higher in the common carotid artery when a person is 10 years of age (p < 0.01 and 0.05). However, during aging, Ep and stiffness (beta) increase to a higher extent in the aorta than in the common carotid artery, with a significantly higher Ep and stiffness (beta) in the aorta when a person is 45 years and older (45 years: p < 0.05 and p = NS; 60 years: p < 0.001 and p < 0.001; 70 years: p < 0.01 and p < 0.01). CONCLUSIONS: This investigation demonstrates regional differences in diameter change and compliance in the common carotid artery and abdominal aorta and implies that the abdominal aorta is more prone to degenerative changes than the common carotid artery. This may be one etiologic factor for the regional differences in vascular disease.
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