Novel Approach to the Quantitation of Regional Left Ventricular Systolic and Diastolic Function Using Tissue Doppler Imaging to Create a Myocardial Velocity Profile and Gradient
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概要
- 論文の詳細を見る
The myocardial velocity profile (MVP) and gradient (MVG) between the endocardium and epicardium of the left ventricular (LV) wall measured by color-coded tissue Doppler imaging (TDI) are new indices for evaluating regional LV myocardial function. However, accurate recording and measurement of the MVP is difficult using conventional methodology because of the stochastic nature of the ultrasound signal ; that is, the effect of speckled noise. The aim of this study was to validate the accuracy and establish the validity of a newly developed method for measuring the MVP and MVG using 10 clinically normal controls and 10 patients with a hypertensive hypertrophied LV posterior wall. A non-isotropic, averaging algorithm was developed that was capable of obtaining a stable MVP (averaged MVP). Averaged MVP was recorded using parasternal, LV short-axis, color-coded TDI, placing regions of interest along the LV posterior wall with the reference point for angle-correction being at the center of LV contraction. The velocity from epicardium to endocardium within the region of interest was automatically angle-corrected to calculate the velocity component radially relative to the LV cavity and was spatially averaged along the circumference within the region of interest. Inter- and intraobserber variabilities of measurements were lower in the averaged MVP and MVG than in the conventional MVP and MVG. The correlation coefficients of the linear regression lines of systolic and early diastolic MVPs in the LV posterior wall were higher in all controls and hypertensive patients with the averaged method than with the conventional TDI procedures. The mean peak systolic and early diastolic MVGs were lower in the hypertensive group than in the controls. In conclusion, the newly developed averaged MVP provides a stable and reproducible index for the quantitative assessment of regional LV myocardial function.
- 社団法人日本循環器学会の論文
- 2003-04-20
著者
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Ito S
Department Of Digestive And Cardiovascular Medicine University Of Tokushima Graduate School
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Kanda Ryoichi
Toshiba medical systems corporation
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abe yasuhiko
Toshiba medical systems corporation
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Ito Susumu
Department Of Digestive And Cardiovascular Medicine University Of Tokushima Graduate School
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Tanaka Hideji
Cardiovascular Section Higashi Tokushima National Hospital National Hospital Organization
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Ito Susumu
徳島大学 大学院ヘルスバイオサイエンス研究部臓器病態治療医学
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Yamada Hirotsugu
The Second Department of Internal Medicine, School of Medicine, The University of Tokushima
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Tabata Tomotsugu
The Second Department of Internal Medicine, School of Medicine, The University of Tokushima
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Ito Susumu
The Second Department of Internal Medicine, School of Medicine, The University of Tokushima
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Tabata Tomotsugu
Department Of Digestive And Cardiovascular Medicine The University Of Tokushima Graduate School Of M
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Tabata Tomotsugu
The Second Department Of Internal Medicine School Of Medicine The University Of Tokushima
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Oishi Yoshifumi
Cardiovascular Section, Higashi Tokushima National Hospital, National Hospital Organization
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Oki Takashi
Cardiovascular Section, Higashi Tokushima National Hospital, National Hospital Organization
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ISHIMOTO Takeo
Cardiovascular Section, Higashi Tokushima National Hospital, National Hospital Organization
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Abe Yasuhiko
Toshiba Corporation Medical Systems Research And Development Center
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Ishimoto Takeo
Cardiovascular Section Higashi Tokushima National Hospital National Hospital Organization
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Oki T
Cardiovascular Section Higashi Tokushima National Hospital National Hospital Organization
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Ito Susumu
Department Of Digestive And Cardiolovascular Medicine Tokushima University Hospital
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Fujimoto Sayuri
Cardiovascular Section,National Higashi Tokushima Hospital
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Tanaka Hideji
The Second Department of Internal Medicine School of Medicine,The University of Tokushima
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Fujimoto Sayuri
Cardiovascular Section National Higashi Tokushima Hospital
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Oki Takashi
Cardiovascular Section Higashi Tokushima National Hospital National Hospital Organization
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Kanda Ryoichi
Toshiba Corporation Medical Systems Research And Development Center
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Oishi Yoshifumi
Cardiovascular Section Higashi Tokushima National Hospital National Hospital Organization
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Tabata Tomotsugu
The Second Department Of Internal Medicine School Of Medicine University Of Tokushima
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Tabata Tomotsugu
Department Of Digestion And Cardiovascular Medicine University Of Tokushima
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Ito S
The Second Department Of Internal Medicine The University Of Tokushima School Of Medicine
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Ito Susumu
The Second Department Of Internal Medicine School Of Medicine The University Of Tokushima
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Fujimoto S
Cardiovascular Section,National Higashi Tokushima Hospital
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Tabata T
The Second Department of Internal Medicine School of Medicine,The University of Tokushima
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Tanaka H
The Second Department of Internal Medicine School of Medicine,The University of Tokushima
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Yamada H
The Second Department of Internal Medicine School of Medicine,The University of Tokushima
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Oishi Y
Cardiovascular Section,National Higashi Tokushima Hospital
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Ishimoto T
Cardiovascular Section,National Higashi Tokushima Hospital
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Abe Y
Toshiba Corporation,Medical Systems Research and Development Center
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Kanda R
Toshiba Corporation,Medical Systems Research and Development Center
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Tanaka Hideji
Cardiovascular Section, Higashi Tokushima National Hospital, National Hospital Organization
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