Abstract:
:The proximal flow convergence method of multiplying color Doppler aliasing velocity by flow convergence surface area has yielded a new means of quantifying flow rate by noninvasively derived measurements. Unlike previous methods of visualizing the turbulent jet of mitral regurgitation on color flow Doppler mapping, flow convergence methods are less influenced by machine factors because of the systematic structure of the laminar flow convergence region. However, recent studies have demonstrated that the flow rate calculated from the first aliasing boundary of color flow Doppler imaging is dependent on orifice size, flow rate, aliasing velocity and therefore on the distance from the orifice chosen for measurement. In this study we calculated the regurgitant flow rates acquired by use of multiple proximal aliasing boundaries on color Doppler M-mode traces and assessed the effect of distances of measurement and aliasing velocities on the calculated regurgitant flow rate. Six sheep with surgically induced mitral regurgitation were studied. The distances from the mitral valve leaflet M-mode line to the first, second, and third sequential aliasing boundaries on color Doppler M-mode traces were measured and converted to the regurgitant flow rates calculated by applying the hemispheric flow equation and averaging instantaneous flow rates throughout systole. The flow rates that were calculated from the first, second, and third aliasing boundaries correlated well with the actual regurgitant flow rates (r = 0.91 to 0.96). The mean percentage error from the actual flow rates were 151% for the first aliasing boundary, 7% for the second aliasing boundary, and -43% for the third aliasing boundary; and the association between aliasing velocities and calculated flow rates indicates an inverse relationship, which suggests that in this model, there were limited velocity-distance combinations that fit with a hemispheric assumption for flow convergence geometry. The second aliasing boundary with an aliasing velocity, of 102 cm/sec, (which was achieved by use of a 4 kHz pulse repetition frequency, a 3.75 MHz transducer, and no color baseline shift), provided the closest fit to the actual regurgitant flow rates (r = 0.99; y = 0.95x + 0.07). The averaged calculated flow rates from all aliasing velocities also resulted in excellent correlation (r = 0.97; y = 0.99x + 0.5). A hemispheric flow convergence method that is based on color Doppler M-mode echocardiography is a feasible and automatable method for quantifying mitral regurgitant rate.(ABSTRACT TRUNCATED AT 400 WORDS)
journal_name
Am Heart Jjournal_title
American heart journalauthors
Zhang J,Jones M,Shandas R,Valdes-Cruz LM,Murillo A,Yamada I,Kang SU,Weintraub RG,Shiota T,Sahn DJdoi
10.1016/0002-8703(93)90025-5subject
Has Abstractpub_date
1993-02-01 00:00:00pages
449-58issue
2 Pt 1eissn
0002-8703issn
1097-6744pii
0002-8703(93)90025-5journal_volume
125pub_type
杂志文章abstract::Detection of mild hypertension by a small number of casual blood pressures may be inaccurate for the determination of average blood pressure. Nonetheless, casual pressures remain the basis for the diagnosis and treatment of hypertensive patients. We compared casual and noninvasive ambulatory blood pressure monitoring ...
journal_title:American heart journal
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更新日期:1987-01-01 00:00:00
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pub_type: 杂志文章,随机对照试验
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pub_type: 杂志文章,多中心研究,随机对照试验
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更新日期:2019-02-01 00:00:00
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pub_type: 杂志文章,多中心研究
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pub_type: 杂志文章
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pub_type: 杂志文章,多中心研究,随机对照试验
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pub_type: 临床试验,杂志文章
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doi:10.1016/s0002-8703(96)90272-0
更新日期:1996-04-01 00:00:00
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doi:10.1016/s0002-8703(76)80117-2
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pub_type: 杂志文章
doi:10.1016/s0002-8703(96)90008-3
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更新日期:1995-01-01 00:00:00
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pub_type: 杂志文章,多中心研究,随机对照试验
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更新日期:2019-02-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/0002-8703(92)90992-5
更新日期:1992-10-01 00:00:00
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