Research on diastolic properties of the myocardium by imaging propagation of shear wave along heart wall

剪切波沿心壁传播成像研究心肌舒张特性

• 批准号: 17206043
• 负责人: KANAI Hiroshi
• 金额: $ 32.45万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17206043/
• 关键词: Heart diseases; Medical ultrasonics; Myocardial elasticity; Phased tracking method; Noninvasive measurement; Tissue characterization; Myocardial viscosity; Lamb wave propagation; 動脈硬化症; 動脈壁弾性特性; 心臓壁粘性特性; 心臓疾患; 心臓壁弾性特性

By ultrasonic measurement of the myocardial motion, we have already found that pulsive waves are spontaneously excited by aortic-valve closure at end-systole. Since myocardial viscoelasticity is essential in the evaluation of heart diastolic properties, this study makes the physiological phenomenon to be measured noninvasively measured in vivo as follows:1 Using a sparse sector scan, the pulsive waves were measured almost simultaneously at several thousand points set along the heart wall at a sufficiently high frame rate. The consecutive spatial phase distributions clearly revealed wave propagation along the heart wall. The phase velocity of the wave is determined for each frequency component. By comparing the dispersion of the phase velocity with the theoretical one of the Lamb wave, which propagates along the viscoelastic plate immersed in blood, the instantaneous viscoelasticity is determined noninvasively.2 We realized the principle of the measurement in a clinical ultrasonic diagn … More ostic system.3 By actuating a small pulse in an elastic spherical shell, which was made as a model of the heart, we confirmed that the viscoelasticity of the spherical shell can be measured with an error less than 10% of the viscoelasticity measured by the mechanical test.4 By applying the developed method to 5 healthy subjects, we confirmed the sufficient reproducibility of the propagation velocity of the pulsive wave among the consecutive cardiac cycles.5 We confirmed that the difference among the viscoelasticity values estimated from the 5 subjects is less than 20% and the transient of the viscoelasticity just after the aortic valve closure is similar. The viscoelasticity estimates are similar to those measured for the canine heart wall in literature.6 By applying the method to 10 patients with old myocardial infarction, we found that the amplitude and the propagation speed were decreased in each of the diseased areas. These results correspond to that obtained by using the longitudinal waves in literature.7 In conclusion, based on the new findings, we developed a means to measure the myocardial viscoelasticity in vivo. These clinical results indicate that the method has a potential for noninvasively revealing myocardial heterogeneity. Less

通过对心肌运动的超声测量，我们已经发现脉冲波是由收缩末期主动脉瓣关闭自发激发的。由于心肌粘弹性对于评估心脏舒张特性至关重要，因此本研究采用如下方式在体内无创测量生理现象：1使用稀疏扇形扫描，以足够高的帧速率在沿心壁设置的数千个点上几乎同时测量脉冲波。连续的空间相位分布清楚地揭示了波沿心壁的传播。波的相速度是针对每个频率分量确定的。通过将相速度的色散与沿着浸入血液中的粘弹性板传播的兰姆波的理论相速度的色散进行比较，可以无创地确定瞬时粘弹性。2我们实现了临床超声诊断口腔系统中的测量原理。3通过在弹性球壳（作为心脏模型制作）中驱动小脉冲，我们证实了瞬时粘弹性。 可以测量球壳的粘弹性，其误差小于机械测试测量的粘弹性的 10%。4 通过将开发的方法应用于 5 名健康受试者，我们确认了脉冲波在连续心动周期中的传播速度具有足够的再现性。5 我们确认，5 名受试者估计的粘弹性值之间的差异小于 20%，并且 主动脉瓣关闭后粘弹性的瞬态是相似的。粘弹性估计与文献中对犬心壁的测量结果类似。6 通过将该方法应用于 10 名陈旧性心肌梗塞患者，我们发现每个病变区域的振幅和传播速度均有所下降。这些结果与文献中使用纵波获得的结果相对应。7 总之，根据新发现，我们开发了一种测量体内心肌粘弹性的方法。这些临床结果表明该方法具有无创揭示心肌异质性的潜力。较少的

项目成果

Modification of the phased-tracking method for reduction of artifacts in estimated artery wall deformation

• DOI: 10.1109/tuffc.2006.145
• 发表时间: 2006-11-01
• 期刊: IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
• 影响因子: 3.6
• 作者: Hasegawa, Hideyuki;Kanai, Hiroshi
• 通讯作者: Kanai, Hiroshi

Investigation of frequency characteristics in cutting of soft tissue using prototype ultrasonic knives

• DOI: 10.1143/jjap.46.4793
• 发表时间: 2007-07-01
• 期刊: JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS
• 作者: Ebina, Kosuke;Hasegawa, Hideyuki;Kanai, Hiroshi
• 通讯作者: Kanai, Hiroshi

Fetal myocardial thickening measured by ultrasonic-based technique called 'phased-tracking method'

• DOI: 10.1159/000093889
• 发表时间: 2006-01-01
• 期刊: FETAL DIAGNOSIS AND THERAPY
• 影响因子: 2.2
• 作者: Kunii, Shutaro;Sugawara, Junichi;Okamura, Kunihiro
• 通讯作者: Okamura, Kunihiro

Improved Imaging of the Carotid Artery in the Short-axis Plane by a Mechanical Scanning Ultrasonic Probe

通过机械扫描超声探头改进颈动脉短轴平面成像

• 发表时间: 2007
• 期刊: Journal of Medical Ultrasonics 34
• 作者: R. Inada;Y. Nakamura;A. Oota,;Kazuki Kudo
• 通讯作者: Kazuki Kudo

Assessment of Vibration of the Myocardium

心肌振动的评估

• 发表时间: 2006
• 作者: S. Kidera;T. Sakamoto and T. Sato;Hiroshi Kanai
• 通讯作者: Hiroshi Kanai