二维斑点追踪技术与Tei指数联合评价慢性心衰患者左心室功能及扭转运动的研究

Evaluation of left ventricular function and twist in patients with chronic heart failure using two-dimensional speckle tracking technology combing Tei index

目的探讨慢性心衰患者的左心室旋转、扭转运动及Tei指数与左心室功能的关系,为临床检测慢性心衰患者心肌运动力学特征及左心室功能提供可靠的指标。方法选取慢性心衰患者79例（心功能Ⅱ级32例,心功能Ⅲ级26例,心功能Ⅳ级21例）,健康对照者28名。采用二维斑点追踪技术和常规超声心动图检查,采集心尖四腔心切面二尖瓣环组织多普勒频谱、左心室心底水平和心尖水平二维图像,测量并计算慢性心衰患者与健康对照者左心室整体扭转角度、短轴切面各节段室壁旋转角度、Tei指数,分析上述指标在各组间的差异性及其之间的相关性。结果 （1）Tei指数在健康对照组、心功能Ⅱ级组、心功能Ⅲ级组、心功能Ⅳ级组分别为0.33±0.19、0.37±0.18、0.46±0.31、0.49±0.33,各组间比较差异有统计学意义（χ^2=88.31,P〈0.01）,且Tei指数随心功能降低,逐渐增大。（2）左心室整体扭转角度在健康对照组、心功能Ⅱ级组、心功能Ⅲ级组、心功能Ⅳ级组分别为（12.89±2.65）、（12.29±1.94）、（12.38±2.13）、（8.46±2.90）度,各组间比较差异有统计学意义（F=25.99,P〈0.01）,心功能Ⅳ级组与健康对照组、心功能Ⅱ级组、心功能Ⅲ级组两两比较,差异均有统计学意义（q=6.43、5.71、4.17,P均〈0.05）。（3）健康对照组及心功能Ⅱ-Ⅳ级组受检者左心室心底水平各节段室壁的旋转角度间差异均有统计学意义（F=9.51、9.47、7.41、10.27、9.42、11.34,P均〈0.01）。心底水平各节段室壁的旋转角度与Tei指数呈正相关（r=0.327、0.277、0.266、0.321、0.306、0.325,P均〈0.01）,且前壁相关性最好。（4）4组受检者左心室心尖水平各节段室壁的旋转角度间差异均有统计学意义（F=6.17、3.49、3.46、3.50、3.48、2.81,P均〈0.01）。心尖水平各节段室壁的旋转角度与Tei指数呈负相关（r=-0.362、-0.278、-0.251、-0.279、-0.290、-0.288,P均〈0.01）,且前壁相关性最好。（5）左心室整体扭转角度与Tei指数呈负相关（r=-0.443,P〈0.01）,直线相关方程：左心室整体扭转角度=-18.30 Tei指数＋18.89。结论慢性心衰患者左心室整体扭转角度、短轴切面各节段室壁的旋转角度减小,而Tei指数增大。左心室整体扭转角度与Tei指数呈负相关。二维斑点追踪技术与Tei指数可以对慢性心衰患者左心室力学运动的改变和左心室功能进行评价。

Objective To explore the relationship among the left ventricular rotation and twist, Tei index and left ventricular function in chronic heart failure patients and provide reliable indicator of chronic heart left ventricular myocardial function and mechanical movement. Methods Seventy-nine chronic heart failure patients with cardiac function class Ⅱ（32 cases）, cardiac function class Ⅲ（26 cases） and cardiac function class Ⅳ（21 cases） and 28 healthy volunteer were included. All subjects underwent conventional echocardiography and two dimensional-speckle tracking imaging. The mitral annulus tissue Doppler spectrums at apical four chambers view, two-dimensional images of left ventricle at basal and apical level were acquired. The left ventricular twist, segmental rotation at short axis view and Tei index were measured. The differences were compared and the correlations were analyzed. Results（1） There were significant differences for Tei index among the four group（χ^2=88.31, P〈0.01）. The Tei index of healthy control group and chronic heart failure patients with cardiac function class Ⅱ, class Ⅲ and class Ⅳ were 0.33±0.19, 0.37±0.18, 0.46±0.31 and 0.49±0.33. The Tei index gradually increased when the heart function decreased.（2） The left ventricular twist were also significantly different among the four groups（F=25.99, P〈0.01）. The left ventricular twist of healthy control group and chronic heart failure patients with cardiac function class Ⅱ, class Ⅲ and class Ⅳ were（12.89±2.65）°,（12.29±1.94）°,（12.38±2.13）° and（8.46±2.90）°. The left ventricular twist gradually decreased when the heart function decreased. The differences between chronic heart failure patients with cardiac function class Ⅳ and healthy control group, chronic heart failure patients with cardiac function class Ⅱ and class Ⅲ were significant（q=6.43, 5.71 and 4.17, all P〈0.05）.（3） The left ventricular segmental rotations at basal level were significantly different among healthy control group and chronic heart failure patients with cardiac function class Ⅱ, Ⅲ and Ⅳ（F=9.51, 9.47, 7.41, 10.27, 9.42 and 11.34, all P〈0.01）. The left ventricular segmental rotations were positively correlated with Tei index and the segmental rotation of anterior wall was most correlated with Tei index（r=0.327, 0.277, 0.266, 0.321, 0.306 and 0.325, all P〈0.01）.（4） The left ventricular segmental rotations at apical level were significantly different among four groups（F=6.17, 3.49, 3.46, 3.50, 3.48 and 2.81, all P〈0.01）. The left ventricular segmental rotations were negatively correlated with Tei index and the segmental rotation of anterior wall was most correlated with Tei index（r=-0.362,-0.278,-0.251,-0.279,-0.290 and-0.288, all P〈0.01）.（5） The left ventricular twist and Tei index were negatively correlated（r=-0.443, P〈0.01）. Conclusions The left ventricular twist and segmental rotation at short axis view in patients with chronic heart failure decreased and Tei index gradually increased. The left ventricular twist and Tei index were negatively correlated. The combination of two-dimensional speckle tracking technology and Tei index could achieve noninvasive assessment of left ventricular mechanical movement and left heart function in chronic heart failure patients.