Dambrauskaite Virginija, Delcroix Marion, Claus Piet, Herbots Lieven, D'hooge Jan, Bijnens Bart, Rademakers Frank, Sutherland George R
Department of Cardiology, University Hospital Gasthuisberg, Leuven, Belgium.
J Am Soc Echocardiogr. 2007 Oct;20(10):1172-80. doi: 10.1016/j.echo.2007.02.005. Epub 2007 Jun 13.
Right ventricular (RV) failure is the main cause of mortality in patients with pulmonary hypertension (PH). Therefore, there is an increasing interest for the assessment of RV function. This study aimed to evaluate the regional RV function in patients with PH by using ultrasonic strain rate imaging.
In all, 27 patients with PH and 27 control subjects were studied by ultrasonic strain rate imaging. The regional longitudinal deformation was measured in the RV free wall divided into two segments. A subgroup of 16 patients had concomitant invasive hemodynamic measurements.
In patients with PH, deformation parameters were significantly lower compared with that of control subjects (basal strain rate -2.28 +/- 0.9 vs -2.94 +/- 0.9 s(-1); strain -28 +/- 13% vs -42 +/- 11%; apical strain rate -1.05 +/- 1.38 vs -2.60 +/- 0.9 s(-1); strain -13 +/- 16% vs -41 +/- 11%, respectively). The deformation parameters in the apical segment were reduced more than in the basal segment (the segment-wise comparison with P < .002 for strain rate and P < .0001 for strain) in the patient group. The reduction of the apical deformation was related to the severity of RV afterload. Strong correlations were found between the apical strain and invasively measured mean pulmonary arterial pressure (R = 0.82, P < .0001) and pulmonary vascular resistance (R = 0.73, P < .001) and echocardiographically estimated hemodynamic parameters, RV size and global function, and exercise capacity (evaluated by a 6-minute walk test expressed as a percentage of the expected value).
Strain rate imaging provides a new tool to quantify regional RV dysfunction in patients with PH and reveals a characteristic regional pattern of abnormal RV free wall function.
右心室（RV）衰竭是肺动脉高压（PH）患者死亡的主要原因。因此，对右心室功能评估的兴趣日益增加。本研究旨在通过超声应变率成像评估肺动脉高压患者的右心室局部功能。
共有27例肺动脉高压患者和27例对照者接受了超声应变率成像研究。在分为两段的右心室游离壁测量局部纵向变形。16例患者的亚组同时进行了有创血流动力学测量。
与对照组相比，肺动脉高压患者的变形参数显著降低（基底段应变率-2.28±0.9对-2.94±0.9 s⁻¹；应变-28±13%对-42±11%；心尖段应变率-1.05±1.38对-2.60±0.9 s⁻¹；应变-13±16%对-41±11%）。患者组心尖段的变形参数比基底段降低得更多（应变率的节段性比较P<0.002，应变为P<0.0001）。心尖段变形的降低与右心室后负荷的严重程度相关。心尖段应变与有创测量的平均肺动脉压（R=0.82，P<0.0001）、肺血管阻力（R=0.73，P<0.001）以及超声心动图估计的血流动力学参数、右心室大小和整体功能以及运动能力（通过6分钟步行试验评估，以预期值的百分比表示）之间存在强相关性。
应变率成像为量化肺动脉高压患者右心室局部功能障碍提供了一种新工具，并揭示了右心室游离壁功能异常的特征性局部模式。
