You Xiang-dong, Pu Zhao-xia, Peng Xian-jing, Zheng Sheng-zhou
Department of Ultrasound, Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou 310009, China.
Chin Med J (Engl). 2007 Jul 5;120(13):1172-5.
Tissue Doppler imaging (TDI) has provided an objective means to quantify global and regional left ventricular (LV) and right ventricular (RV) function with improved accuracy and greater reproducibility than conventional echocardiography. This study was conducted to assess RV myocardial systolic activation by TDI in subjects with pulmonary arterial hypertension (PAH).
A total of 30 patients with PAH and 30 healthy volunteers, all comparable in age and sex, underwent standard Doppler echo and TDI. Using pulsed Doppler echocardiography combined with TDI, the following regional parameters were evaluated in three different myocardial segments (RV basal lateral wall, basal septal, and LV basal lateral) on apical 4-chamber view: systolic (Sm), early- and late-diastolic (Em and Am) peak velocities. RV myocardial systolic activation delay was defined as the difference in time to peak TDI systolic velocities between the RV basal lateral wall and basal septal. In addition, RV end-diastolic and end-systolic areas were measured to calculate RV fractional area change from the same apical 4-chamber view.
Compared with the control group, patients with PAH showed increased RA and RV end-diastolic diameter (RA: (4.5 +/- 1.2) cm vs (3.0 +/- 0.8) cm, P < 0.05 and RV: (4.8 +/- 1.9) cm vs (3.4 +/- 0.5) cm, P < 0.05) and reduced RV fractional area change; (35 +/- 14)% vs (56 +/- 9)%, P < 0.05. These PAH patients showed lower myocardial peak velocities and a significant activation delay compared with controls (P < 0.05). Moreover, a strong correlation between RV myocardial systolic activation delay and RV fractional area change was shown in patients with pulmonary arterial hypertension (r = -0.82).
In PAH, RV myocardial systolic activation was markedly delayed, which was directly related to the RV fractional area change. RV myocardial systolic activation delay assessed by TDI could offer a unique approach to predict RV dysfunction.
组织多普勒成像（TDI）提供了一种客观手段，用于量化左心室（LV）和右心室（RV）的整体及局部功能，与传统超声心动图相比，其准确性更高且重复性更好。本研究旨在通过TDI评估肺动脉高压（PAH）患者的右心室心肌收缩激活情况。
总共30例PAH患者和30名健康志愿者，年龄和性别匹配，均接受标准多普勒超声心动图和TDI检查。使用脉冲多普勒超声心动图结合TDI，在心尖四腔视图的三个不同心肌节段（右心室基底部侧壁、基底部间隔和左心室基底部侧壁）评估以下局部参数：收缩期（Sm）、舒张早期和晚期（Em和Am）峰值速度。右心室心肌收缩激活延迟定义为右心室基底部侧壁和基底部间隔之间TDI收缩期峰值速度达到峰值的时间差。此外，从同一心尖四腔视图测量右心室舒张末期和收缩末期面积，以计算右心室面积变化分数。
与对照组相比，PAH患者的右心房和右心室舒张末期直径增加（右心房：（4.5±1.2）cm对（3.0±0.8）cm，P<0.05；右心室：（4.8±1.9）cm对（3.4±0.5）cm，P<0.05），右心室面积变化分数降低；（35±14）%对（56±9）%，P<0.05。与对照组相比，这些PAH患者的心肌峰值速度较低且激活延迟显著（P<0.05）。此外，肺动脉高压患者的右心室心肌收缩激活延迟与右心室面积变化分数之间存在强相关性（r=-0.82）。
在PAH中，右心室心肌收缩激活明显延迟，这与右心室面积变化分数直接相关。通过TDI评估的右心室心肌收缩激活延迟可为预测右心室功能障碍提供一种独特方法。
