应用超声二维斑点追踪显像（2DSTI）技术应变指标评估冠心病患者左心房功能。

选取2021年6月至2023年12月解放军东部战区总医院经冠状动脉造影检查确诊的冠心病患者83例，其中左心室射血分数（LVEF）≥50%的患者43例，作为LVEF正常组，LVEF＜50%的患者40例，作为LVEF减低组。另选择同期健康体检者22人作为健康对照组。采用常规超声心动图测量左心房容积指数（LAVI）、左心房最大容积（LAV_max）、左心房最小容积（LAV_mim）、左心房收缩前容积（LAV_preA）、左心房排空分数（LAEF）。采用2DSTI技术测量左心房储器期应变（LAS_r）、管道期应变（LAS_cd）和收缩期纵向应变（LAS_ct）。采用方差分析比较3组研究对象左心房功能指标的差异。绘制受试者操作特征（ROC）曲线分析左心房期相应变指标与左心室整体纵向应变（LVGLS）对冠心病患者心脏功能损害的诊断效能、确定截断值，并采用DeLong检验比较各指标诊断效能的差异。

LVEF正常组常规超声心动图左心房功能指标LAVI、LAV_max、LAV_mim、LAV_preA、LAEF与健康对照组比较，差异均无统计学意义（P均＞0.05）；LVEF正常组2DSTI技术应变指标LAS_r、LAS_cd低于健康对照组[（30.86±10.55）% vs（41.79±6.89）%；（15.48±6.57）% vs（20.39±3.76）%]，差异具有统计学意义（P＜0.05），而LVGLS、LAS_ct与健康对照组比较，差异无统计学意义（P＞0.05）。LVEF减低组常规超声心动图左心房功能指标LAVI、LAV_max、LAV_mim、LAV_preA、LAEF及左心房应变指标LAS_r、LAS_cd、LAS_ct与健康对照组和LVEF正常组比较[（44.95±21.22）ml/m²vs（30.56±20.55）ml/m²vs（32.47±16.51）ml/m²；（30.41±6.32）ml vs（19.00±5.01）ml vs（22.88±4.24）ml；（19.45±7.33）ml vs（7.37±2.57）ml vs（9.36±2.64）ml；（32.13±6.54）ml vs（13.73±4.77）ml vs（26.13±7.17）ml；（26.77±10.90）% vs（45.77±7.17）% vs（45.05±12.34）%；（17.37±10.89）% vs（41.79±6.89）% vs（30.86±10.55）%；（8.78±5.33）% vs（20.39±3.76）% vs（15.48±6.57）%；（8.79±7.95）% vs（15.00±8.74）% vs（15.38±6.64）%]，差异均具有统计学意义（F=21.613、4.833、0.547、13.579、6.688、31.436、21.613、4.833，P均＜0.001）。ROC曲线分析显示，LAS_r、LAS_cd、LAS_ct和LVGLS诊断冠心病患者心脏功能损害的曲线下面积（AUC）分别为0.859、0.810、0.535和0.778，DeLong检验显示LAS_r、LAS_cd、LVGLS诊断冠心病患者心脏功能损害效能差异无统计学意义（P＞0.05），均高于LAS_ct，差异具有统计学意义（P＜0.001、＜0.001、=0.008）；LAS_r诊断冠心病患者心脏功能损害截断值为34.2%时敏感度、特异度分别为90.9%、78.4%；LAS_cd诊断冠心病患者心脏功能损害截断值为14.9%时敏感度、特异度分别为95.5%、62.5%。

2DSTI技术左心房应变指标LAS_r、LAS_cd可以较左心室应变指标LVGLS更早反映冠心病患者亚临床期心脏功能损害，有望成为冠心病患者心脏功能早期损害的重要补充评价指标；不同LVEF水平的冠心病患者左心房期相应变具有不同的损害特征，该特征可以间接反映冠心病患者病情严重程度。

To evaluate left atrial function in patients with coronary atherosclerotic heart disease (CAD) via strain parameters derived from two-dimensional speckle tracking imaging (2DSTI).

Eighty-three patients with CAD confirmed by coronary angiography were included in this study. Among them, 43 patients with a left ventricular ejection fraction (LVEF) ≥ 50% were assigned to a normal LVEF group, and 40 patients with an LVEF ＜50% to a reduced LVEF group. Additionally, 22 healthy individuals who underwent routine health examinations during the same period were enrolled as a control group. Left atrial volume index (LAVI), maximal left atrial volume (LAV_max), minimal left atrial volume (LAV_min), pre-atrial contraction left atrial volume (LAV_preA), and left atrial emptying fraction (LAEF) were measured by conventional echocardiography, while left atrial reservoir strain (LAS_r), conduit strain (LAS_cd), and contraction strain (LAS_ct) were assessed using two-dimensional speckle tracking echocardiography (2D-STE). Analysis of variance (ANOVA) was used to compare differences in left atrial function among the three groups. Receiver operating characteristic (ROC) curve analysis was performed to evaluate and compare the diagnostic performance of left atrial phasic strain parameters and the left ventricular global longitudinal strain (LVGLS) in identifying impaired cardiac function in CAD patients, and to determine their optimal cutoff values.

There were no significant differences in conventional echocardiographic parameters of left atrial function, including LAVI, LAV_max, LAV_min, LAV_preA, and LAEF, between the normal LVEF group and the healthy control group (all P＞0.05). The left atrial strain indices LAS_r and LAS_cd measured by 2DSTE in the normal LVEF group were significantly lower than those of the healthy control group [(30.86±10.55)% vs (41.79±6.89)%; (15.48±6.57)% vs (20.39±3.76)%, both P＜0.05]. However, there was no significant difference in LVGLS or LAS_ct between the normal LVEF group and the healthy control group (both P＞0.05). In the reduced LVEF group, conventional echocardiographic parameters of left atrial function including LAVI, LAVmax, LAVmin, LAVpreA, and LAEF, as well as the left atrial strain indices LAS_r, LAS_cd, and LAS_ct, were statistically different from those of both the healthy control group and the normal LVEF group [(44.95±21.22) ml/m² vs (30.56±20.55) ml/m²vs (32.47±16.51) ml/m²; (30.41±6.32) ml vs (19.00±5.01) ml vs (22.88±4.24) ml; (19.45±7.33) ml vs (7.37±2.57) ml vs (9.36±2.64) ml; (32.13±6.54) ml vs (13.73±4.77) ml vs (26.13±7.17) ml; (26.77±10.90)% vs (45.77±7.17)% vs (45.05±12.34)%; (17.37±10.89)% vs (41.79±6.89)% vs (30.86±10.55)%; (8.78±5.33)% vs (20.39±3.76)% vs (15.48±6.57)%; (8.79±7.95)% vs (15.00±8.74)% vs (15.38±6.64)%, all P＜0.05]. ROC curve analysis revealed that the area under the curve (AUC) values for LAS_r, LAS_cd, LAS_ct, and LVGLS in diagnosing impaired cardiac function in CAD patients were 0.859, 0.810, 0.535, and 0.778, respectively. The DeLong test showed that the LAS_r, LAS_cd, and LVGLS indicators had comparable efficacy in diagnosing cardiac function impairment in CAD patients (P＞0.05), and they were all significantly superior to the LAS_ct indicator (P＜0.05). For LAS_r, a cutoff value of 34.2% yielded a sensitivity of 90.9% and specificity of 78.4%. For LAS_cd, a cutoff value of 14.9% provided a sensitivity of 95.5% and specificity of 62.5%.

In CAD patients, left atrial strain parameters derived from 2D-STE, including LAS_r and LAS_cd, can detect subclinical cardiac dysfunction earlier than LVGLS, and thus may serve as valuable complementary indicators for the early assessment of cardiac impairment in CAD patients. Moreover, CAD patients with different LVEF levels exhibit distinct patterns of left atrial phasic strain impairment, which may indirectly reflect the severity of the disease.