Assessment Of The Left Ventricular Systolic Function In Patients With Non-ST-Segment Elevation Myocardial Infarction By Two-Dimensional Speckle-Tracking Echocardiography

Part1:Assessment of the left ventricular strain in patients with non-ST-segment elevation myocardial infarction by two-dimensional speckle-tracking echocardiographyObjects We sought to explore the clinical value of two-dimensional speckle tracking echocardiography (2D-STE) for the identification of non-ST-segment elevation myocardial infarction (NSTEMI) by assessing left ventricular strains in patients with NSTEMI.Methods Sixty patients diagnosed with AMI, were divided into two groups based on electrocardiogram(ECG), NSTEMI group containing 30 patients, STEMI group containing 30 patients, and thirty age and gender matched subjects were involved as the control group. Global longitudinal and circumferential strains (GLS and GCS) were assessed by 2D-STE, so were territorial longitudinal and circumferential strains (TLS and TCS).Results ① All left ventricular segments of patients from NSTEMI group and STEMI group were divided into normal segments and infarcted segments based on the selective coronary arteriography(SCA). ②Patients with NSTEMI and STEMI had lower value assessed by GLS and infarcted segments TLS compared with patients in control group (P<0.05). Patients with STEMI had no significant difference assessed by GLS and infarcted segments TLS compared with patients in NSTEMI group. ③ Patients with NSTEMI and STEMI had lower value assessed by GCS and infarcted segments TCS compared with patients in control group (P<0.05). Patients with STEMI had no significant difference assessed by GCS and infarcted segments TCS compared with patients in NSTEMI group. ④ GLS correlated with GCS (r=0.618, P<0.001) significantly.Conclusions Longitudinal and circumferential strains have provided useful information for clinical diagnosis of NSTEMI.Part2:Assessment of the left ventricular layer-specific strains in patients with non-ST-segment elevation myocardial infarction by two-dimensional speckle-tracking echocardiographyObjects We sought to explore the clinical value of two-dimensional speckle tracking echocardiography (2D-STE) for the identification of non-ST-segment elevation myocardial infarction (NSTEMI) by assessing left ventricular layer-specific strains at endocardium, mid-myocardium and epicardium layers in patients with NSTEMI.Methods Sixty patients diagnosed with AMI, were divided into two groups based on electrocardiogram (ECG), NSTEMI group containing 30 patients, STEMI group containing 30 patients, and thirty age and gender matched subjects were involved as the control group. Layer-specific global longitudinal and circumferential strains (GLS and GCS) were assessed at endocardium, midmyocardium and epicardium by 2D-STE, so were territorial longitudinal and circumferential strains(TLS and TCS). The absolute differences between endocardial and epicardial GLS, GCS, infarcted segments TLS, TCS (ΔGLS, ΔGCS, ΔTLS, ΔTCS) were calculated.Results ①All left ventricular segments of patients from NSTEMI group and STEMI group were divided into normal segments and infarcted segments based on the selective coronary arteriography(SCA). ②Patients with NSTEMI and STEMI had lower value in all 3 myocardial layers assessed by GLS, ΔGLS and infarcted segments TLS, ATLS compared with patients in control group (P<0.05). Patients with STEMI had no significant difference in all 3 myocardial layers assessed by GLS, ΔGLS and infarcted segments TLS, ΔTLS compared with patients in NSTEMI group. ③ Patients with NSTEMI and STEMI had lower value in all 3 myocardial layers assessed by GCS, ΔGCS and infarcted segments TCS, ΔTCS compared with patients in control group (P<0.05). Patients with STEMI had no significant difference in all 3 myocardial layers assessed by GCS, ΔGCS and infarcted segments TCS, ΔTCS compared with patients in NSTEMI group, except for GCS of epicardium, which is lower than the value of NSTEMI group(P<0.05). ④Endocardium GLS correlated with endocardium GCS (r=0.632, P<0.001) significantly, Epicardium GLS correlated with epicardium GCS (r=0.533, P<0.001) significantly, AGLS correlated with ΔGCS (r=0.369, P<0.001) significantly.Conclusions Longitudinal and circumferential strains at endocardium, midmyocardium and epicardium have provided useful information for clinical diagnosis of NSTEMI.