多普勒超声心动图评价兔左心室舒张功能与充盈压

目的 探讨舒张早期二尖瓣口血流速度(E)、瓣环运动速度(Ea)及E/Ea比值等多普勒指标在评价左心室舒张功能和充盈压方面的价值.方法 采用缩窄腹主动脉法建立18只左心室压力超负荷兔舒张功能不全模型(模型组),应用多普勒超声心动图观察左心大小、室壁厚度、射血分数(EF)及舒张功能指标,心导管测量左心室舒张末压(LVEDP).8只健康兔作为LVEDP对照(对照组).结果 模型组左心房增大、左心室肥厚、LVEDP明显增高(P＜0.01);多普勒指标Ea降低、E/Ea增高(P均＜0.01),而E/A无明显变化;LVEDP与E/Ea呈正相关(r=0.54,P<0.05).结论 在左心室肥厚所致的舒张功能不全动物模型中,Ea降低反映心肌主动松弛功能减退,E/Ea与LVEDP结合,可综合评价左心室舒张功能及充盈压.

Doppler echocardiographic estimation of left ventricular diastolic function and filling pressure on rabbits

Objective To explore the value of the combination of early diastolic mitral inflow (E) and mitral annulus velocity (Ea) in the estimation of left ventricular diastolic function and filling pressure. Methods Animal models of pressure overload-induced left ventricular hypertrophy (LVH) were established with abdominal aortic coarctation in 18 New-Zealand rabbits (model group), and 8 healthy rabbits served as normal controls. Two-dimensional and Doppler echocardiographic measurements were detected before abdominal coarctation and in LVH models. Results Compared with before abdominal coarctation, left atrial volume and left ventricular wall thickness increased in model group after abdominal coarctation (P<0.01), and left ventricular end diastolic pressure (LVEDP) significantly increased (P<0.01). Ea significantly decreased, and the ratio of E/Ea increased (all P<0.01), but no significant difference of E/A was found. Significant correlation was found between LVEDP and E/Ea (r=0.54, P<0.05). Conclusion In LVH rabbit models, Ea decreasing reflects the reduction of active relaxation of myocardial dysfunction, and E/Ea combination with LVEDP is useful in the evaluation of diastolic function and filling pressure.