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Noninvasive method for measuring local pulse wave velocity by dual pulse wave Doppler: in vitro and in vivo studies.

Wang Z, Yang Y, Yuan LJ, Liu J, Duan YY, Cao TS - PLoS ONE (2015)

Bottom Line: The coefficient of variation (CV) of the intra- and inter- measurements for local PWV were 3.46% and 4.96%, for the PWV of the homogeneous rubber tubing were 0.99% and 1.98%.In the in vivo study, a significantly higher local PWV of LCCA was found in the hypertensive patients as compared to that in healthy subjects (6.29±1.04 m/s vs. 5.31±0.72 m/s, P = 0.019).The CV of the intra- and inter- measurements in hypertensive patients were 2.22% and 3.94%, in healthy subjects were 2.07% and 4.14%.

View Article: PubMed Central - PubMed

Affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China.

ABSTRACT

Objectives: To evaluate the validity and reproducibility of a noninvasive dual pulse wave Doppler (DPWD) method, which involves simultaneous recording of flow velocity of two independent sample volumes with a measurable distance, for measuring the local arterial pulse wave velocity (PWV) through in vitro and in vivo studies.

Methods: The DPWD mode of Hitachi HI Vision Preirus ultrasound system with a 5-13MHz transducer was used. An in vitro model was designed to compare the PWV of a homogeneous rubber tubing with the local PWV of its middle part measured by DPWD method. In the in vivo study, local PWV of 45 hypertensive patients (25 male, 49.8±3.1 years) and 45 matched healthy subjects (25 male, 49.3±3.0 years) were investigated at the left common carotid artery (LCCA) by DPWD method.

Results: In the in vitro study, the local PWV measured by DPWP method and the PWV of the homogeneous rubber tubing did not show statistical difference (5.16 ± 0.28 m/s vs 5.03 ± 0.15 m/s, p = 0.075). The coefficient of variation (CV) of the intra- and inter- measurements for local PWV were 3.46% and 4.96%, for the PWV of the homogeneous rubber tubing were 0.99% and 1.98%. In the in vivo study, a significantly higher local PWV of LCCA was found in the hypertensive patients as compared to that in healthy subjects (6.29±1.04 m/s vs. 5.31±0.72 m/s, P = 0.019). The CV of the intra- and inter- measurements in hypertensive patients were 2.22% and 3.94%, in healthy subjects were 2.07% and 4.14%.

Conclusions: This study demonstrated the feasibility of the noninvasive DPWD method to determine the local PWV, which was accurate and reproducible not only in vitro but also in vivo studies. This noninvasive echocardiographic method may be illuminating to clinical use.

No MeSH data available.


The methodology of the in vitro study.Panel A, the PWVA-B measurement, the top panel was the two dimensional echocardiographic imaging. The velocity spectra recorded at point A and B by pulse wave Doppler were displayed at the middle and bottom, respectively. The pressure curve recorded by the pressure transducer was shown under each spectrum. The time delay between the transducer and point A and B were respectively measured by foot detection using the intersecting tangent method (125ms and 184ms). Thus the transit time between A and B could be calculated as 184−125 = 59ms. Panel B, the local PWVM measured by the DPWD method, the simultaneously recorded dual velocity spectra were shown. The transit time between these two sites (9ms) was measured by wave foot detection using the intersecting tangent method. PWVA-B, pulse wave velocity between point A and B. DPWD, dual pulse wave Doppler; PWVM, pulse wave velocity at the middle of point A and B.
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pone.0120482.g002: The methodology of the in vitro study.Panel A, the PWVA-B measurement, the top panel was the two dimensional echocardiographic imaging. The velocity spectra recorded at point A and B by pulse wave Doppler were displayed at the middle and bottom, respectively. The pressure curve recorded by the pressure transducer was shown under each spectrum. The time delay between the transducer and point A and B were respectively measured by foot detection using the intersecting tangent method (125ms and 184ms). Thus the transit time between A and B could be calculated as 184−125 = 59ms. Panel B, the local PWVM measured by the DPWD method, the simultaneously recorded dual velocity spectra were shown. The transit time between these two sites (9ms) was measured by wave foot detection using the intersecting tangent method. PWVA-B, pulse wave velocity between point A and B. DPWD, dual pulse wave Doppler; PWVM, pulse wave velocity at the middle of point A and B.

Mentions: Ten pairs of PWVA-B with different distance and PWVM using the new method were measured. The in vitro experimental parameters and results of the PWV measurements are summarized in Table 1. Fig. 2 shows a representative PWVA-B measurement and local PWVM by the DPWD method based on the in vitro model. The mean value of the PWV between point A and B (PWVA-B = 5.03 ± 0.15 m/s) and the local PWV of a short segment at middle (PWVM = 5.16 ± 0.28 m/s) did not show difference with statistical significance (p = 0.075).


Noninvasive method for measuring local pulse wave velocity by dual pulse wave Doppler: in vitro and in vivo studies.

Wang Z, Yang Y, Yuan LJ, Liu J, Duan YY, Cao TS - PLoS ONE (2015)

The methodology of the in vitro study.Panel A, the PWVA-B measurement, the top panel was the two dimensional echocardiographic imaging. The velocity spectra recorded at point A and B by pulse wave Doppler were displayed at the middle and bottom, respectively. The pressure curve recorded by the pressure transducer was shown under each spectrum. The time delay between the transducer and point A and B were respectively measured by foot detection using the intersecting tangent method (125ms and 184ms). Thus the transit time between A and B could be calculated as 184−125 = 59ms. Panel B, the local PWVM measured by the DPWD method, the simultaneously recorded dual velocity spectra were shown. The transit time between these two sites (9ms) was measured by wave foot detection using the intersecting tangent method. PWVA-B, pulse wave velocity between point A and B. DPWD, dual pulse wave Doppler; PWVM, pulse wave velocity at the middle of point A and B.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4364771&req=5

pone.0120482.g002: The methodology of the in vitro study.Panel A, the PWVA-B measurement, the top panel was the two dimensional echocardiographic imaging. The velocity spectra recorded at point A and B by pulse wave Doppler were displayed at the middle and bottom, respectively. The pressure curve recorded by the pressure transducer was shown under each spectrum. The time delay between the transducer and point A and B were respectively measured by foot detection using the intersecting tangent method (125ms and 184ms). Thus the transit time between A and B could be calculated as 184−125 = 59ms. Panel B, the local PWVM measured by the DPWD method, the simultaneously recorded dual velocity spectra were shown. The transit time between these two sites (9ms) was measured by wave foot detection using the intersecting tangent method. PWVA-B, pulse wave velocity between point A and B. DPWD, dual pulse wave Doppler; PWVM, pulse wave velocity at the middle of point A and B.
Mentions: Ten pairs of PWVA-B with different distance and PWVM using the new method were measured. The in vitro experimental parameters and results of the PWV measurements are summarized in Table 1. Fig. 2 shows a representative PWVA-B measurement and local PWVM by the DPWD method based on the in vitro model. The mean value of the PWV between point A and B (PWVA-B = 5.03 ± 0.15 m/s) and the local PWV of a short segment at middle (PWVM = 5.16 ± 0.28 m/s) did not show difference with statistical significance (p = 0.075).

Bottom Line: The coefficient of variation (CV) of the intra- and inter- measurements for local PWV were 3.46% and 4.96%, for the PWV of the homogeneous rubber tubing were 0.99% and 1.98%.In the in vivo study, a significantly higher local PWV of LCCA was found in the hypertensive patients as compared to that in healthy subjects (6.29±1.04 m/s vs. 5.31±0.72 m/s, P = 0.019).The CV of the intra- and inter- measurements in hypertensive patients were 2.22% and 3.94%, in healthy subjects were 2.07% and 4.14%.

View Article: PubMed Central - PubMed

Affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China.

ABSTRACT

Objectives: To evaluate the validity and reproducibility of a noninvasive dual pulse wave Doppler (DPWD) method, which involves simultaneous recording of flow velocity of two independent sample volumes with a measurable distance, for measuring the local arterial pulse wave velocity (PWV) through in vitro and in vivo studies.

Methods: The DPWD mode of Hitachi HI Vision Preirus ultrasound system with a 5-13MHz transducer was used. An in vitro model was designed to compare the PWV of a homogeneous rubber tubing with the local PWV of its middle part measured by DPWD method. In the in vivo study, local PWV of 45 hypertensive patients (25 male, 49.8±3.1 years) and 45 matched healthy subjects (25 male, 49.3±3.0 years) were investigated at the left common carotid artery (LCCA) by DPWD method.

Results: In the in vitro study, the local PWV measured by DPWP method and the PWV of the homogeneous rubber tubing did not show statistical difference (5.16 ± 0.28 m/s vs 5.03 ± 0.15 m/s, p = 0.075). The coefficient of variation (CV) of the intra- and inter- measurements for local PWV were 3.46% and 4.96%, for the PWV of the homogeneous rubber tubing were 0.99% and 1.98%. In the in vivo study, a significantly higher local PWV of LCCA was found in the hypertensive patients as compared to that in healthy subjects (6.29±1.04 m/s vs. 5.31±0.72 m/s, P = 0.019). The CV of the intra- and inter- measurements in hypertensive patients were 2.22% and 3.94%, in healthy subjects were 2.07% and 4.14%.

Conclusions: This study demonstrated the feasibility of the noninvasive DPWD method to determine the local PWV, which was accurate and reproducible not only in vitro but also in vivo studies. This noninvasive echocardiographic method may be illuminating to clinical use.

No MeSH data available.