| Project/Area Number |
11695092
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Circulatory organs internal medicine
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| Research Institution | Tokyo Woman's Medical University |
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Principal Investigator |
SUGAWARA Motoaki Tokyo Women's Medical University, Department of Cardiovascular Sciences, Professor, 医学部, 教授 (60010914)
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| Co-Investigator(Kenkyū-buntansha) |
UJIIE Hiroshi Tokyo Women's Medical University, DepartmentNeurosurgery, Lecturer, 医学部, 講師 (00138869)
OKAYAMA Fumihiko Okayama University, Graduate School of Medicine and Dentistry Medical School, Professor, 医学部, 教授 (70029114)
NAKAZAWA Makoto Tokyo Women's Medical University Department of Pediatric Cardiology, Professor, 医学部, 教授 (10075567)
常 徳華 東京女子医科大学, 医学部, 助手
NIKI Kiyomi Tokyo Women's Medical University, Department of Cardiovascular Sciences, Research Associate, 医学部, 助手 (40218095)
CHANG Dehua Tokyo Women's Medical University, Department of Cardiovascular Sciences, Research Associate
今井 康晴 東京女子医科大学, 医学部, 教授 (30075246)
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| Project Period (FY) |
1999 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥5,900,000 (Direct Cost: ¥5,900,000)
Fiscal Year 2001: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 2000: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1999: ¥2,100,000 (Direct Cost: ¥2,100,000)
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| Keywords | wave intensity / cardiac contractility / diastolic function / reflected waves / carotid artery / ultrasound / echo tracking / color Doppler / 心機能 / 超音波法 / wave intensity / 負荷 / 心臓 |
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| Research Abstract |
Wave intensity (WI) is a new index for evaluating ventriculo-arterial interactions. Wave intensity is defined as (dP/dt)(dU/dt) at any site of the circulation, where dP/dt and dU/dt are the time derivatives of blood pressure and velocity, respectively. Arterial wave intensity in normal subjects has two positive sharp peaks. The first peak occurs during early systole, the magnitude of which increases markedly with increases in cardiac contractility The second peak, which occurs towards the end of ejection, is related to the ability of the left ventricle to actively stop aortic blood flow and the compliance of the artery. During mid-ejection between the two positive peaks of WI, negative peaks are often observed. The magnitude and the timing of these peaks give information about the strength of wave reflections and the distance between the measuring point and the position of the reflections.
We developed a new ultrasonic on-line system for obtaining WI, and assessed its validity. The system is composed of a computer, a WI unit and an ultrasonic machine (Aloka, Tokyo) equipped with a combined tissue imaging (5 or 7.5 MHz) and Doppler (5 MHz) transducer. The WI unit receives RF echo signals and color Doppler signals from the ultrasonic machine, and calculates the change in diameter of the artery (M-mode echo tracking) and the mean blood velocity through the sampling gate (color M-mode Doppler). Since arterial pressure waveforms and diameter change waveforms are similar, a blood pressure waveform is obtained from a diameter change waveform by calibrating its peak and bottom values by systolic and diastolic blood pressure measured with a cuff-type manometer.
We investigated the characteristics of carotid arterial wave intensity in patients with heart disease.Wave intensity has the potential to provide meaningftil information about the working condition of the heart interacting with the arterial system.
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