The role of speckle tracking echocardiography in the diagnosis of coronary artery disease and the evaluation of clinical outcomes after revascularization in patients suspected of non- ST-segment elevation acute coronary syndrome and stable angina pectoris and its relationship to syntax 2 score

Objective: Coronary artery disease (CAD), which is a chronic disease, is a social problem for our country and the whole world, with both a serious economic cost and negative effects on quality of life. Coronary angiography (CAG) is considered the gold standard for hemodynamic evaluation of lesions as well as coronary stenosis. However, since CAG is an invasive method, the importance of non-invasive diagnostic methods that predict CAD gain is increasing. In addition to conventional echocardiography, 2D speckle tracking echocardiography (2D STE) provides a more objective and clearer evaluation of left ventricular segmental wall motion disorder and systolic functions. Syntax and Syntax 2 scores are scoring systems used to determine the anatomical severity of CAD. When the results of the percutaneous intervention were evaluated, it was seen that the Syntax 2 score was superior to the Syntax score results. The aim of our study many fold: i) to assess left ventricle contractility before and after percutaneous coronary intervention (PCI) in detail with 2D STE, ii) to determine predictive power of this assessment in the diagnosis and follow-up of CAD via sensitivity and selectivity analysis, and iii) to investigate the relationship or correlation between PCI and the Syntax 2 score. Our target subject population in this study are patients with prior CAD diagnosis using CAG and normal left ventricular wall motion who are hospitalized with the suspicion of non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and stable angina pectoris (SAP), and decided for single vessel revascularization. 56 Materials and Methods: Thirty patients meeting our study and strain analysis criteria were recruited between February 2021 and February 2022. CAG was performed on the patients and PCI was applied to the responsible lesion during angiography. 2-dimensional global longitudinal strain (GLS) and segmental longitudinal strain (SLS) analyzes were performed on all apical images using the speckle tracking method. After 3 months, the control strain echocardiography of these patients was repeated, and the clinical results of revascularization were followed. Results: The mean age of the patients included in our study was calculated as 59.3±11.1 years. 21 (70%) of all patients were male. Smoking rate of the patients was 53.3% (n=16), and the percentage of those with a family history of coronary artery disease was 40%. According to the analysis, CAD was found in 20% of the patients, hypertension in 33.3%, diabetes mellitus in 43.3% and hyperlipidemia in 43.3%. In the study, we have compared "before" and "3 months after" the procedure values of GLS, SLS, and "the mean strain of myocardial regions fed by the coronary vessels" parameters of patients. We have found statistically significant increases in the median values of all parameters in the "3 months after the procedure" measurements compared to the pre-procedure period (p≤0.001). The diagnosis of 14 (46.7%) of patients in our study was NSTE-ACS and 16 (53.3%) was SAP. When strain values were analyzed according to diagnosis, pre-procedure CX strain value were calculated as -18.05(-18.7--14.9) and -19.75(-22.65--18.3) for patients with NSTE-ACS and SAP diagnosis respectively and the difference was found to be statistically significant (p=0.013). "Before the procedure" RCA strain values were calculated as -16.7(-18.8--15) and -19.1(-20.1--17.15) for NSTE-ACS and SAP groups respectively, and the difference between the groups was found statistically significant (p=0.022). "3 months after" the procedure RCA strain values were calculated as -19.2 (-21--17.2) and -21.45 (-23--19.65) for NSTE-ACS and SAP groups respectively and this difference was also found significant statistically (p=0.019). We have divided the patients into 2 groups based on if their Syntax 2 score is below or above 22. We had 18 (60%) and 12 (40%) patients in the low and high 57 score groups respectively. We have then compared "before" and "3 months after" the procedure values of LAD, CX, and RCA strain parameters for both groups. Our analysis revealed that there is not any statistically significant change in any of these parameters (p>0.05) for both groups. Conclusion: Our study shows that "speckle tracking echocardiography" is a non-invasive method that is predictive in the diagnosis of coronary artery disease, which also provides significant benefits in terms of clinical follow-up of patients after revascularization, and can detect myocardial deformation in the early period without visible changes in myocardial tissue. However, we should note that our study is a single-center, prospective study and therefore, in order to obtain results which could be more reliable, multicenter studies with a larger patient groups are required.