目的 探讨二维整体峰值应变指标在不同程度心力衰竭患者中的变化特征.方法 35例心肌梗死合并心力衰竭患者按照左心室射血分数(LVEF)分为轻度(14例)、中度(13例)及重度(8例)心力衰竭三组.28名健康受试者为正常对照组.应用二维斑点追踪技术分别测量收缩期左心室的纵向峰值应变(LS)、径向应变(RS)和圆周应变(CS),分别计算三种应变的平均值作为左心室整体纵向应变(GLS)、整体径向应变(GRS)及整体圆周应变(GCS);同时应用常规二维超声测量LVEF和左心室容积(LVEDV)等,比较各组间整体二维应变和心功能,分析GLS、GRS、GCS在不同心力衰竭组中的变化及其与LVEF的关系.结果 轻、中、重度心力衰竭组分别与正常对照组相比较,GLS、GRS、GCS差异均有统计学意义(P<0.01);三组心力衰竭组间相比,随着LVEF的减低GLS明显减低,三组心力衰竭组间GLS差异有统计学意义(P<0.05);重度心力衰竭组GCS明显低于轻度、中度心力衰竭组(P<0.05);但轻度与中度心力衰竭组间GCS差异无统计学意义(P>0.05);三组心力衰竭组之间GRS差异无统计学意义(P>0.05).相关分析显示GLS与LVEF呈高度相关(r=-0.65,P<0.01)、GCS与LVEF有一定的相关性(r=-0.55,P<0.01).结论 GLS、GRS、GCS在不同程度的心力衰竭组中变化不同,GLS与LVEF的变化关系密切.GLS、GRS、GCS的变化可能反映了心肌收缩功能不同程度的损伤.
Objective To observe the characteristics of the two-dimensional global strain index in patients with different degrees heart failure with speckle tracking echocardiography. Methods Totally 35 myocardial infarction patients with heart failure and 28 healthy subjects (control group) were enrolled in the study. The patients were divided into mild (n=14), moderate (n=13), and severe heart failure subgroup (n=8) according to left ventricular ejection fraction (LVEF). The systolic longitudinal strain (LS), radial strain (RS) and circumferential strain (CS) were measured of left ventricular with two-dimensional speckle tracking technique. The average value of left ventricular 18 segmental LS, RS and CS was calculated as the global longitudinal strain (GLS), the global radial strain (GRS) and the global circumference strain (GCS), respectively. LVEF and left ventricular end diastolic volume (LVEDV) were also measured with conventional two-dimensional echocardiography. The global two-dimensional strain and heart function between two groups were compared. The change of GLS, GRS and GCS of different heart failure and the relationship between them and LVEF were analyzed. Results Compared with control group, GLS, GRS and GCS reduced in heart failure groups (P<0.01). In heart failure groups, GLS significantly decreased with the decrease of LVEF, the difference of GLS was significant (P<0.05). GCS in severe heart failure subgroup was lower significantly than that in mild and moderate heart failure subgroups (P<0.05). No significant difference was found in GCS between mild and moderate heart failure subgroups (P>0.05). There was no significant difference in GRS among heart failure subgroups (P>0.05). GLS was closely correlated to LVEF (r=-0.65, P<0.01), GCS was also correlated to LVEF (r=-0.55, P<0.01). Conclusion The changes of GLS, GRS and GCS is different in different degrees of heart failure. GLS is closely correlated to the change of LVEF. The change of GLS, GRS and GCS may reflect degrees of myocardial injury.