Kuroiwa N, Nakamura K, Kawahira M, Sanada J, Hashimoto S
J Cardiogr. 1986 Mar;16(1):149-58.
Left ventricular relaxation property was evaluated by pulsed Doppler echocardiography. The indices obtained from Doppler signals within the left ventricle (LV) during the isovolumic relaxation period (IRF) were compared with the hemodynamic parameters obtained from cardiac catheterization studies. Subjects of this study were four patients with hypertrophic cardiomyopathy, four with hypertensive heart disease, three with angina pectoris, and seven normal subjects. All of them had no wall motion abnormalities and their ejection fractions were more than 0.60. The three indices of IRF were the time interval from the start of IRF to the time immediately before the rapid filling flow (isovolumic relaxation time; IRT), the time interval from the start to the peak (acceleration time; AcT), and the slope from the start to the peak (acceleration rate; AcR). The peak pressure (peak P) was measured at the same time. The positive and negative deflections of the first derivative of left ventricular (LV) pressure (+dp/dt and -dp/dt) and the time constant of LV pressure fall (time constant T) were calculated from LV pressure using a micromanometer-tipped angiocatheter. The end-diastolic volume index (EDVI), end-systolic volume index (ESVI), and ejection fraction (EF) were calculated from the LV angiogram. There were no significant correlations between the three IRF indices (IRT, AcT and AcR) and the hemodynamic parameters (peak P, EDVI, +dp/dt and -dp/dt). However, the time constant T, which is a good index of LV relaxation property and which is relatively free from afterload and preload, correlated well with IRT (r = 0.75, p less than 0.001), AcT (r = 0.60, p less than 0.01), and AcR (r = -0.66, p less than 0.01). It was concluded that the indices obtained from the blood flow patterns of the left ventricle during isovolumic relaxation were useful for estimating left ventricular relaxation property non-invasively and quantitatively.
采用脉冲多普勒超声心动图评估左心室舒张功能。将等容舒张期（IRF）左心室内多普勒信号获得的指标与心导管检查获得的血流动力学参数进行比较。本研究对象包括4例肥厚型心肌病患者、4例高血压性心脏病患者、3例心绞痛患者和7例正常受试者。所有患者均无室壁运动异常，射血分数均大于0.60。IRF的三个指标分别为从IRF开始到快速充盈血流前即刻的时间间隔（等容舒张时间；IRT）、从开始到峰值的时间间隔（加速时间；AcT）以及从开始到峰值的斜率（加速率；AcR）。同时测量峰值压力（峰值P）。使用微测压导管从左心室压力计算左心室压力一阶导数的正负偏转（+dp/dt和-dp/dt）以及左心室压力下降的时间常数（时间常数T）。根据左心室血管造影计算舒张末期容积指数（EDVI）、收缩末期容积指数（ESVI）和射血分数（EF）。三个IRF指标（IRT、AcT和AcR）与血流动力学参数（峰值P、EDVI、+dp/dt和-dp/dt）之间无显著相关性。然而，时间常数T是左心室舒张功能的良好指标，相对不受后负荷和前负荷影响，与IRT（r = 0.75，p小于0.001）、AcT（r = 0.60，p小于0.01）和AcR（r = -0.66，p小于0.01）相关性良好。得出结论，等容舒张期左心室血流模式获得的指标有助于无创且定量地评估左心室舒张功能。
