Doppler assessment of aortic stenosis: a 25-operator study demonstrating why reading the peak velocity is superior to velocity time integral
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Aims Measurements with superior reproducibility are useful clinically and research purposes. Previous reproducibility
studies of Doppler assessment of aortic stenosis (AS) have compared only a pair of observers and have not
explored the mechanism by which disagreement between operators occurs. Using custom-designed software which
stored operators’ traces, we investigated the reproducibility of peak and velocity time integral (VTI) measurements
across a much larger group of operators and explored the mechanisms by which disagreement arose. ...................................................................................................................................................................................................
Methods
and results
Twenty-five observers reviewed continuous wave (CW) aortic valve (AV) and pulsed wave (PW) left ventricular
outflow tract (LVOT) Doppler traces from 20 sequential cases of AS in random order. Each operator unknowingly
measured each peak velocity and VTI twice. VTI tracings were stored for comparison. Measuring the peak is much
more reproducible than VTI for both PW (coefficient of variation 10.1 vs. 18.0%; P < 0.001) and CW traces (coeffi-
cient of variation 4.0 vs. 10.2%; P < 0.001). VTI is inferior because the steep early and late parts of the envelope are
difficult to trace reproducibly. Dimensionless index improves reproducibility because operators tended to consistently
over-read or under-read on LVOT and AV traces from the same patient (coefficient of variation 9.3 vs.
17.1%; P < 0.001). ...................................................................................................................................................................................................
Conclusion It is far more reproducible to measure the peak of a Doppler trace than the VTI, a strategy that reduces measurement
variance by approximately six-fold. Peak measurements are superior to VTI because tracing the steep slopes
in the early and late part of the VTI envelope is difficult to achieve reproducibly
studies of Doppler assessment of aortic stenosis (AS) have compared only a pair of observers and have not
explored the mechanism by which disagreement between operators occurs. Using custom-designed software which
stored operators’ traces, we investigated the reproducibility of peak and velocity time integral (VTI) measurements
across a much larger group of operators and explored the mechanisms by which disagreement arose. ...................................................................................................................................................................................................
Methods
and results
Twenty-five observers reviewed continuous wave (CW) aortic valve (AV) and pulsed wave (PW) left ventricular
outflow tract (LVOT) Doppler traces from 20 sequential cases of AS in random order. Each operator unknowingly
measured each peak velocity and VTI twice. VTI tracings were stored for comparison. Measuring the peak is much
more reproducible than VTI for both PW (coefficient of variation 10.1 vs. 18.0%; P < 0.001) and CW traces (coeffi-
cient of variation 4.0 vs. 10.2%; P < 0.001). VTI is inferior because the steep early and late parts of the envelope are
difficult to trace reproducibly. Dimensionless index improves reproducibility because operators tended to consistently
over-read or under-read on LVOT and AV traces from the same patient (coefficient of variation 9.3 vs.
17.1%; P < 0.001). ...................................................................................................................................................................................................
Conclusion It is far more reproducible to measure the peak of a Doppler trace than the VTI, a strategy that reduces measurement
variance by approximately six-fold. Peak measurements are superior to VTI because tracing the steep slopes
in the early and late part of the VTI envelope is difficult to achieve reproducibly
Date Issued
2018-12-01
Date Acceptance
2017-08-23
Citation
EHJ Cardiovascular Imaging / European Heart Journal - Cardiovascular Imaging, 2018, 19 (12), pp.1380-1389
ISSN
2047-2412
Publisher
Oxford University Press (OUP)
Start Page
1380
End Page
1389
Journal / Book Title
EHJ Cardiovascular Imaging / European Heart Journal - Cardiovascular Imaging
Volume
19
Issue
12
Copyright Statement
© The Author(s) 2018. Published by Oxford University Press on behalf of the European Society of Cardiology. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL
Sponsor
British Heart Foundation
British Heart Foundation
British Heart Foundation
Grant Number
FS/10/38/28268
FS/12/12/29294
FS/14/27/30752
Subjects
echocardiography
valvular heart disease
Publication Status
Published
Date Publish Online
2018-01-15