Uematsu M, Miyatake K, Tanaka N, Matsuda H, Sano A, Yamazaki N, Hirama M, Yamagishi M
Department of Cardiovascular Dynamics, National Cardiovascular Center Research Institute, Osaka, Japan.
J Am Coll Cardiol. 1995 Jul;26(1):217-23. doi: 10.1016/0735-1097(95)00158-v.
This study was performed to assess a new indicator of regional left ventricular contraction determined by a two-dimensional tissue Doppler imaging technique.
Recent studies have demonstrated that instantaneous tissue motion velocity can be noninvasively assessed by tissue Doppler imaging. However, quantitative assessment of regional left ventricular contraction is still difficult because of the effects of the Doppler angle of incidence and parallel motion of the whole heart.
We assessed left ventricular wall motion in 11 normal subjects, 14 patients with an old myocardial infarction (anteroseptal in 7, posterior in 7) and 8 patients with dilated cardiomyopathy. Tissue Doppler velocity was corrected by the Doppler angle of incidence after the hypothetical center of contraction was set. Subsequently, the myocardial velocity gradient between the endocardium and epicardium was determined from the velocity profile along each radial line from the center of contraction by using least squares linear regression.
In normal subjects, peak myocardial velocity gradient was lower in the anteroseptal wall (mean [+/- SD] 1.69 +/- 0.53 s-1) than in the posterior wall (3.28 +/- 0.67 s-1, p < 0.01). Myocardial velocity gradient in the infarct regions was significantly lower (anteroseptal 0.58 +/- 0.41 s-1, p < 0.05; posterior 0.17 +/- 0.27 s-1, p < 0.01) than that in normal subjects as well as that in the corresponding noninfarct regions (2.84 +/- 0.37 s-1 and 1.48 +/- 0.25 s-1, p < 0.01, respectively). In patients with dilated cardiomyopathy, myocardial velocity gradient was generally lower (anteroseptal 0.72 +/- 0.59 s-1; posterior 0.93 +/- 0.67 s-1) than that in normal subjects (p < 0.01).
These results demonstrate that regional left ventricular contraction can be quantitatively assessed by the myocardial velocity gradient derived from two-dimensional tissue Doppler imaging. We suggest that myocardial velocity gradient has potential for the quantitative assessment of regional left ventricular contraction abnormalities in patients.
本研究旨在评估一种通过二维组织多普勒成像技术确定的左心室局部收缩新指标。
近期研究表明，组织多普勒成像可无创评估瞬时组织运动速度。然而，由于多普勒入射角和全心平行运动的影响，左心室局部收缩的定量评估仍很困难。
我们评估了11名正常受试者、14名陈旧性心肌梗死患者（前间隔梗死7例，后壁梗死7例）和8例扩张型心肌病患者的左心室壁运动。在设定假设的收缩中心后，根据多普勒入射角校正组织多普勒速度。随后，通过使用最小二乘线性回归，从收缩中心沿每条径向线的速度剖面确定心内膜和心外膜之间的心肌速度梯度。
在正常受试者中，前间隔壁的峰值心肌速度梯度（平均值[±标准差]1.69±0.53 s⁻¹）低于后壁（3.28±0.67 s⁻¹，p<0.01）。梗死区域的心肌速度梯度显著低于正常受试者以及相应的非梗死区域（前间隔分别为0.58±0.41 s⁻¹，p<0.05；后壁为0.17±0.27 s⁻¹，p<0.01；正常受试者前间隔为2.84±0.37 s⁻¹，后壁为1.48±0.25 s⁻¹，p<0.01）。在扩张型心肌病患者中，心肌速度梯度通常低于正常受试者（前间隔为0.72±0.59 s⁻¹；后壁为0.93±0.67 s⁻¹，p<0.01）。
这些结果表明，左心室局部收缩可通过二维组织多普勒成像得出的心肌速度梯度进行定量评估。我们认为心肌速度梯度在定量评估患者左心室局部收缩异常方面具有潜力。
