组织多普勒成像对正常儿童房室环运动的研究

目的探讨组织多普勒成像(TDI)技术定量评价儿童心室功能的应用价值,研究儿童体格及心脏的生长发育对TDI参数的影响。方法用TDI方法测量242例出生后3d至17岁正常健康儿童二尖瓣环侧壁、间壁及三尖瓣环侧壁收缩期峰值速度(Sa)、舒张早期峰值速度(Ea)及舒张晚期峰值速度(Aa),并与临床资料及常规超声心动图指标进行对比研究。结果(1)各取样点Sa、Ea均以<1个月组最低[二尖瓣环侧壁:Sa(4.8±0.7)cm/s,Ea(6.6±1.1)cm/s,间壁:Sa(4.1±0.6)cm/s,Ea(5.0±0.8)cm/s;三尖瓣环Sa(6.2±1.2)cm/s,Ea(6.4±1.0)cm/s],并随年龄增长逐渐增长,1个月～组至1岁～组显著增长[1岁～组二尖瓣环侧壁:Sa(8.5±2.0)cm/s,Ea(16.3±2.6)cm/s,间壁:Sa(7.2±0.8)cm/s,Ea(12.2±1.6)cm/s;三尖瓣环:Sa(12.6±2.3)cm/s,Ea(14.7±2.6)cm/s],1岁～组三尖瓣环Sa、Ea较二尖瓣环更接近年长儿相应测值。二尖瓣环E/Ea值<1个月至7个月～组较高(侧壁9.2±2.1,间壁12.10±2.89),随年龄增长逐渐降低,1岁～组显著降低(侧壁5.9±1.2,间壁7.8±1.3)。(2)年龄、体表面积、心率及左心室舒张末期内径(LVEDD)对多数TDI参数有显著影响。LVEDD是影响二尖瓣环Sa、Ea的主要因素,是二尖瓣环E/Ea值的独立影响因子。结论正常儿童左、右心室收缩及舒张功能随年龄增长逐渐发育,这一发育过程以婴幼儿期最为快速,右心室功能的发育早于左心室,儿童体格及心脏的正常发育对心室收缩及舒张功能的发育有重要影响,LVEDD是左心室收缩及舒张功能的重要影响因素。

A study on atrioventricular annular movement in healthy children by tissue Doppler imaging

OBJECTIVE: Detecting the atrioventricular annular velocity along the long axis of ventricle by tissue Doppler imaging (TDI) is a useful modality to quantitatively assess global myocardial function. The present study was designed to quantitatively assess ventricular function in healthy children by TDI and to evaluate the clinical effect of growth and echocardiographic parameters on TDI velocities during childhood. METHODS: The study enrolled 242 healthy children aged 3 days to 17 years and they were divided into 8 groups: < 1 month of age group (37 cases), 1 month-of age group (28 cases), 7 months-of age group (21 cases), 1 year-of age group (36 cases), 4 years-of age group (40 cases), 7 years-of age group (26 cases), 10 years-of age group (28 cases) and > or = 13 years of age group (26 cases). Pulsed wave TDI velocities were obtained at the lateral mitral annulus (MA-L), basal septum (MA-S) and lateral tricuspid annulus (TA) during ventricular systole (Sa), early diastole (Ea) and late diastole (Aa), and Ea/Aa and E/Ea were obtained. Conventional echocardiography performed done and the parameters of left ventricular end-diastolic dimension (LVEDD), left ventricular ejection fraction (LVEF), the transmitral and transtricuspid flow E wave and A wave velocities and E/A ratio were obtained. TDI parameters were compared with demographic and echocardiographic variables. RESULTS: Sa, Ea and Ea/Aa were the lowest in children < 1 month of age [MA-L: Sa (4.8 +/- 0.7) cm/s, Ea (6.6 +/- 1.1) cm/s; MA-S: Sa (4.1 +/- 0.6) cm/s, Ea (5.0 +/- 0.8) cm/s; TA: Sa (6.2 +/- 1.2) cm/s, Ea (6.4 +/- 1.0) cm/s], and increased with age. The increase was significant from 1 month- to 1 year-of age group 1 year-of age group: MA-L: Sa (8.5 +/- 2.0) cm/s, Ea (16.3 +/- 2.6) cm/s; MA-S: Sa (7.2 +/- 0.8) cm/s, Ea (12.2 +/- 1.6) cm/s; TA: Sa (12.6 +/- 2.3) cm/s, Ea (14.7 +/- 2.6) cm/s. Ea and Sa of TA reached the older children's value earlier than those of the mitral annulus did. Aa increased in the 1 month-of age group compared to < 1 month of age group and remained stable beyond 1 year-of age group. Mitral annulus E/Ea ratio was high among neonates to 7-months-old children (MA-L: 9.2 +/- 2.1, MA-S: 12.1 +/- 2.9), and decreased with age, and there was a significant decrease in 1 year-of age group (MA-L: 5.9 +/- 1.2, MA-S: 7.8 +/- 1.3). In these healthy children, all the above TDI parameters except Aa were influenced by age, body surface area (BSA), LVEDD and heart rate. The influence of age and BSA showed a logarithm model. LVEDD was the main factor that influenced Sa and Ea of MA-L and MA-S, and it was the only single factor that influenced E/Ea ratio at mitral annulus. CONCLUSIONS: This study demonstrated that the left and right ventricular function developed with age in childhood, and it developed most rapidly during infancy and toddler period. The right ventricular function matured earlier than that of the left ventricle. Cardiac growth, age, and heart rate had important clinical effects on TDI velocities during childhood, and LVEDD had the most important influence on left ventricular systolic and diastolic function.