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.