心肌弹性成像对高血压左心室不同构型患者心肌僵硬度的评价

Evaluation of myocardial stiffness by intrinsic cardiac elastography in hypertensivepatients with different types of left ventricular remodeling

目的探讨高频组织多普勒超声心动图弹性成像技术测量舒张末期左心室心肌拉伸的固有波传播速度(IVP),评价高血压左心室不同构型患者心肌僵硬度的可行性和临床价值。方法前瞻性纳入2019年9月至2020年3月在北京朝阳医院治疗的90例高血压患者(左心室正常构型组22例、向心性重构组30例及向心性肥厚组38例)和同期门诊年龄、性别匹配的30例健康者为对照组,均接受包括斑点追踪测量左心室整体纵向应变(GLS)的全面超声心动图检查,采用弹性成像技术定量检测心肌弹性的直接测量指标——心肌拉伸的IVP。比较各组之间IVP是否存在差异,IVP与常用超声心动图参数和GLS的相关性,受试者工作特征(ROC)曲线分析IVP预测左心室向心性肥厚的敏感度和特异度。结果高血压患者IVP高于健康对照组,向心性肥厚组IVP显著高于健康对照组、左心室重构组及正常构型组(均P<0.05)。IVP与左心室后壁厚度(LVPWT)、左心室质量指数(LVMI)、室间隔厚度(IVS)、相对室壁厚度(RWT)、收缩压(SBP)及E/e'呈显著正相关(r=0.732、0.695、0.670、0.652、0.626、0.625,均P<0.01),与GLS、e'average呈负相关(r=-0.593、-0.445,均P<0.001)。ROC曲线分析显示,IVP>179.84 cm/s是预测高血压患者左心室向心性肥厚构型的最佳阈值(敏感度92%,特异度61%)。结论 IVP是无创定量评估高血压左心室重构患者左心室心肌僵硬度的新参数,值得进一步研究应用。

Objective To explore the feasibility and clinical value of end-diastolic left ventricular intrinsic velocity propagation(IVP)of myocardial stretch measured by high-frame rate tissue Doppler echocardiography forevaluating myocardial stiffness in hypertensive patients with different types of left ventricular remodeling.Methods A total of 90 hypertensive patients with different types of left ventricular remodeling(22 patients with normal geometry,30 with concentric remodeling,and 38 with concentric hypertrophy)and 30 healthy controls were prospectively included in this study.All subjects underwent comprehensive echocardiographic examination including speckle tracking and measurement of global longitudinal strain(GLS)of the left ventricle,and IVP of myocardial stretch,which is a direct and quantitative measurement index of myocardial elasticity.The differences of IVP among the groups were compared.The correlations between IVP and common echocardiographic parameters or GLS were analyzed.The sensitivity and specificity of IVP in predicting left ventricular concentric hypertrophy were analyzed by receiver operating characteristic(ROC)curve analysis.Results IVP in hypertensive patients was higher than that of healthy controls,and IVP in the concentric hypertrophy subgroup was significantly higher than that of the other two left ventricular remodeling subgroups(P<0.05).IVP was significantly positively correlated with left ventricular posterior wall thickness,left ventricular mass index,thickness of interventricular septum,relative wall thickness,systolic blood pressure,and E/e’(r=0.732,0.695,0.670,0.652,0.626,and 0.625,respectively;P<0.001 for all),and negatively correlated with GLS and e’average(r=-0.593 and-0.445,respectively).ROC curve analysis showed that IVP>179.84 cm/s was the best threshold for predicting left ventricular concentric hypertrophy in hypertensive patients(sensitivity 92%,specificity 61%).Condusion IVP is a new parameter for noninvasive and quantitative evaluation of left ventricular myocardial stiffness in hypertensive patients with left ventricular remodeling,which is worthy of further study and application.