Relationship between the Deformation Properties of the Left Ventricle and the Severity of Coronary Atherosclerosis in Patients with Coronary Artery Disease

The purpose of this study was to assess the properties of left ventricular myocardial deformation in patients with coronary artery disease (CAD) with various degrees of coronary lesions. Methods and Results: The study included 74 patients with stable angina pectoris Class II-IV aged between 40 and 70 years. All patients underwent the following examinations: assessment of traditional risk factors, physical examination, general clinical and laboratory blood tests, 12-lead ECG, 24-hour ABPM, transthoracic echocardiography, two-dimensional speckle tracking echocardiography (STE), and coronary angiography (CAG). The SYNTAX score was calculated retrospectively according to the SYNTAX score algorithm. All patients were divided into 3 groups: Group 1 included 21 patients with a low SYNTAX score (0–22), for whom standard drug therapy was recommended; Group 2 included 28 patients with an intermediate SYNTAX score (23–32), to whom PCI was recommended; Group 3 included 25 patients with a high SYNTAX score (≥33), to whom CABG was recommended. Left ventricular ejection fraction (LVEF) obtained using the modified biplane Simpson's method was significantly lower in Group 3 than in Groups 1 and 2 (P=0.001); it should be noted that this indicator was within the normative values in Groups 1 and 2, and belonged to the gradation “mild dysfunction.” A more objective quantitative assessment of the contractile function of the LV myocardium was obtained by assessing the GLS and SR. The comparative analysis of the LV myocardial deformation properties in the three studied groups showed that in Group 3 the GLS and SR indicators were significantly lower than in Group 1 (P=0.000 and P=0.0020). Moreover, GLS (global longitudinal strain) and SR (strain rate) were significantly higher in Group 1 than in Group 2 (P=0.0001 and P=0.0133, respectively). GLS significantly correlated with LVEF (r=0.57; P<0.05), E/A (r=0.22; P<0.05), and SYNTAX score (r=-0.63; P<0.05). SR significantly correlated with LVEF (r=0.49; P<0.05) and SYNTAX score (r=-0.37; P<0.05) Conclusion: The results obtained indicate the diagnostic value of STE with the determination of GLS and SR in a comprehensive assessment of the severity of SAD. GLS and SR significantly correlate with the clinical course of the disease, as well as indicators of LV remodeling and LV diastolic dysfunction. STE analysis of GLS and SR has incremental diagnostic value over transthoracic echocardiography in predicting significant CAD.