【作者】 崔嘉萍；

【导师】 刘兰燕； 李路明；

【作者基本信息】 河北医科大学 ， 影像医学与核医学， 2007， 硕士

【摘要】 目的:本研究应用组织多普勒成像（tissue Doppler imaging,TDI）技术测量扩张型心肌病患者的主动脉近端壁运动速度,探讨多普勒组织成像（TDI）评价主动脉弹性变化的应用价值。方法:选取扩张型心肌病患者33例（女性13名,男性20名,平均年龄45.24±11.29岁）,正常志愿者30例（女性12名,男性18名,平均年龄45.57±11.77岁）作为正常对照组。所有受试者肱动脉血压测量之后即刻左侧卧位,连接心电图,行常规经胸超声心动图检查。M型超声分别测量升主动脉瓣上3cm处收缩期和舒张期内径,利用公式计算主动脉膨胀性（D）和僵硬度（β）。转入TVI模式获取升主动脉长轴切面TVI图像,在组织-速度曲线上测量升主动脉同处前壁的运动速度（Sao,Eao,Aao）、加速前时间、扩张加速度。改良Simpson’法测定左室射血分数（LVEF）。结果:1和对照组相比,扩张型心肌病组僵硬度指数（3.38±0.72 vs 1.83±0.47,p<0.05）增高,膨胀度(0.70±0.18cm2 dynes^-1 vs 1.24±0.32cm2dynes^-1,p<0.01)降低,升主动脉前壁S波运动速度（4.40±0.69cm/s vs 6.45±1.29cm/s,p<0.01）降低,差别均有统计学意义。扩张型心肌病组升主动脉前壁E波、A波及扩张加速度均低于对照组,但无统计学意义。左室射血分数（LVEF）与正常组比较差异有显著性意义（P<0.01）。2 DCM组升主动脉前壁S波速度和僵硬度呈明显负相关（r=-0.68,p<0.01）,与膨胀性呈正相关（r=0.39,p<0.05）;升主动脉前壁扩张加速度与主动脉僵硬度呈负相关（r=-0.37,p<0.05）。对照组升主动脉前壁S波速度和僵硬度呈明显负相关（r=-0.69,p<0.01）,与膨胀性呈明显正相关（r=0.60,p<0.01）;升主动脉前壁E波速度和僵硬度呈明显负相关（r=-0.51,p<0.01）,与膨胀性呈正相关（r=0.39,p<0.05）;两组均以S波速度与升主动脉僵硬度之间的相关最密切。3两组中,年龄和主动脉僵硬度均呈正相关（r=0.45,p<0.05;r=0.63,p<0.01）;DCM组年龄与主动脉膨胀性呈负相关（r=-0.38, p<0.05）;和S波速度呈明显负相关（r=-0.59,p<0.01）;对照组年龄与主动脉膨胀性和S波速度呈明显负相关（r=-0.63,p<0.01;r=-0.76,p<0.01）。结论:1升主动脉前壁S波速度降低提示主动脉僵硬度增加,利用TDI方法直接测量主动脉壁的运动速度可以评价主动脉的弹性特征;2扩张型心肌病患者主动脉弹性功能受损;3年龄是主动脉僵硬度的主要决定因素;4 TDI方法测量主动脉壁运动速度具有简单、直接、干扰因素相对较少优点。更多还原

【Abstract】 Objective: The purpose of this study was to evaluate elastic properties of the proximal aorta assessed by tissue Doppler imaging （TDI） in patients with dilated cardiomyo- pathy （DCM）.Methods: Thirty-three patients with DCM （13 female, 20 male; mean age 45.24±11.29 years） were selected,while 30 healthy volunteers （12 female,18 male; mean age 45.57±11.77 years） matched with DCM group in age and gender as control group. After measuring arterial pressure, all subjects immediately examined by conventional echocardiography at left lateral decubitus position and linking ECG at the same time. Internal aortic systolic and diastolic diameters were obtained at 3cm above the aortic valve with M-mode echocardiography. Aortic distensibility (cm2·dynes^-1) and aortic stiffness index were calculated using formulas. On long axis view of ascending aortic tissue velocity imaging （TVI）, ascending aortic upper wall tissue velocities （Aortic S, E, A, cm/sec）, time before acceleration and expanding acceleration were measured 3cm above the aortic valve （the same point as the former） on TVI curve. Left ventricular ejection fraction （LVEF） was calculated by modified Simpson’s method.Results:1 The aortic stiffness index was significantly higher （3.38±0.72 vs 1.83±0.47, P<0.05）, while aortic distensibility and aortic S velocity were significantly lower respectively （0.70±0.18cm2dynes-1 vs 1.24±0.32cm2dynes-1 p< 0.01; 4.40±0.69cm/s vs 6.45±1.29cm/s p<0.01） in patients with DCM than those in healthy subjects. Compared with those of healthy subjects, aortic E, A velocity and expanding acceleration were also lower in DCM patients, but no statistical significance. Statistical significance was noted in left ventricular ejection fraction between two groups（r=p<0.01）.2 In DCM group, aortic S velocity showed a significant negative correlation with aortic stiffness（r=-0.68, p<0.01）, and a positive correlation with aortic distensibility（r = 0.39, p<0.05）; Aortic upper wall expanding acceleration was negatively correlated with （r=-0.37, p<0.05） aortic stiffness. In control group, significant negative correlation was noted between aortic S velocity and aortic stiffness （r=-0.69, p<0.01）, and significant positive correlation between aortic S velocity and aortic distensibility（r=0.60, p<0.01）; Aortic E velocity was negatively correlated well with aortic stiffness（r=-0.51, p<0.01）, and positively with aortic distensibility（r=0.39, p<0.05）. In both group aortic S velocity had a good correlation with artic stiffness. 3 In both group, significant positive correlation was found between age and aortic stiffness （r=0.45, p<0.05; r=0.63, p<0.01, respectively）. In DCM group a negative correlation was noted between age and aortic distensibility（r = -0.38, p<0.05）, and age was significantly negative correlated with aortic S wave velocity（r=-0.59, p<0.01）. In the control group, age was significantly negative correlated with aortic distensibility and aortic S wave velocity（r=-0.63, p<0.01; r=-0.76, p<0.01, respectively）.Conclusions: 1 Reduced aortic S velocity is associated with increased aortic stiffness. Elastic properties of the aorta can be assessed by direct measurement of the movements in the upper aortic wall with TDI; 2 In patients with DCM aortic stiffness increased and aortic S velocity reduced; 3 Age is a definitive clinical factor for aortic stiffness; 4 Compared with traditionary M-mode method, TDI is more simple, more direct and have relative fewer interference factors.更多还原