Prediction of infarct size using two-dimensional speckle tracking echocardiography in acute myocardial infarction

Prediction of an impaired myocardial work using infarct size in acute myocardial infarction

BACKGROUND

The relationship between myocardial infarct size (MIS) on late gadolinium-enhanced cardiac MRI (LGE MRI) and myocardial work (MW) indices assessed with MW echocardiography (MWE) has not been well characterized. This study aimed to determine an impaired MW using MIS in patients with acute myocardial infarction.

METHODS

Left ventricular (LV) two-dimensional speckle-tracking echocardiography, MWE, and LGE MRI were performed in 33 patients with ST-segment elevation myocardial infarction and in 30 age- and sex-comparable controls. LV global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) and MIS were acquired, respectively.

RESULTS

MIS was negatively correlated with GWI (r = -0.60, P  = 0.005), GCW (r =- 0.66, P  = 0.002) and GWE (r = -0.71, P  = 0.0004), but positively correlated with GLS (r = 0.68, P  = 0.001). With the receiver operating characteristic curve, the cutoff value of MIS for the prediction of an impaired GLS was 16.5% [area under the curve (AUC) = 0.867)], an impaired GWI was 19.2% (AUC = 0.727), an impaired GCW was 19.2% (AUC = 0.725), an increased GWW was 15.8% (AUC = 0.656), an impaired GWE was 15.8% (AUC = 0.880).

CONCLUSION

MIS is a strong predictor of impaired MW. Timely reduction of infarct size is essential to improve myocardial function.

Number of segments with motion abnormalities is better correlated with infarct size in acute myocardial infarction

BACKGROUND

The relationship between the number of segments with motion abnormalities (SMA) on the bull's-eye plots of speckle-tracking echocardiography (STE) and myocardial infarct size (MIS) on late gadolinium-enhanced cardiac MRI (LGE-cMRI) has not been well characterized. This study aimed to determine MIS using the number of SMA in patients with acute myocardial infarction (MI).

METHODS

Left ventricular two-dimensional STE and LGE-cMRI were performed in 380 patients with ST-segment elevation MI within 48 h and 5-6 days after primary percutaneous intervention, respectively.

RESULTS

Patients with impaired global and regional myocardial strain, work and greater number of SMA had significantly larger infarcts ( P  < 0.05). Multivariate logistic regression analysis that included myocardial strain, work, and number of SMA showed that total number of SMA [odds ratio (OR) = 1.976; 95% confidence interval (CI): 1.539-2.538, P  < 0.0001], the number of segments with paradoxalic systolic movements (SPSM, OR = 3.703; 95% CI: 2.112-6.493, P  < 0.0001) were independent risk factors of large MIS (>19%). The area under receiver operating characteristic curve (AUC) of 0.904 (0.866~0.942) for total number of SMA was superior to that for global longitudinal strain (GLS, AUC = 0.813, 0.761~0.865), global work efficiency (GWE, AUC = 0.794, 0.730~0.857) and number of SPSM (AUC = 0.851, 0.804-0.899) to predict a large MIS ( P  < 0.05). The optimal cutoff value of total number of SMA was 7, with a sensitivity of 85.31%, a specificity of 81.48%, and an accuracy of 83.27%.

CONCLUSION

Total number of SMA is better associated with infarct size, which provided an incremental prognostic value above established prognostic parameters such as GLS and GWE.

Speckle-Tracking Echocardiography for Detecting Subclinical Left Ventricular Dysfunction in Patients With Familial Hypercholesterolemia

Myocardial ischemia and left ventricular dysfunction have been documented in young adults with familial hypercholesterolemia. We investigated whether speckle-tracking echocardiography can be used to detect subclinically impaired global and regional myocardial function in patients with this lipid disorder. This single-center study included 47 patients with familial hypercholesterolemia and 37 healthy control subjects who underwent transthoracic Doppler echocardiography and speckle-tracking echocardiography from January 2003 through December 2016. Conventional echocardiographic and strain parameters in the 2 groups were analyzed and compared. Left ventricular dimensions were significantly larger at end-diastole (P=0.02) and end-systole (P=0.013), left ventricular walls were significantly thicker (P <0.0001), and the early transmitral/early diastolic mitral annular velocity ratio was significantly higher (P=0.006) in the patient group than in the control group. In the patient group, global longitudinal and circumferential strain values were significantly lower (P <0.0001) and global radial strain values significantly higher (P=0.006); all segmental longitudinal strain (P <0.04) and most segmental circumferential strain values (P ≤0.01) were significantly lower; and some segmental radial strains, especially at the apex, were significantly higher (P ≤0.04). However, average longitudinal, circumferential, and radial strains in the different segments of the 3 main coronary artery territories were significantly lower in the patient group (P <0.01). Global longitudinal strain (r=0.561; P=0.001) and global circumferential strain (r=0.565; P <0.0001) were inversely correlated with low-density-lipoprotein cholesterol levels. We conclude that speckle-tracking echocardiography can be used to detect subclinical global and regional systolic abnormalities in patients with familial hypercholesterolemia.

Analysis of the application of echocardiography technology in diagnosis of acute myocardial infection

The purpose of this study is to enhance the diagnosis and treatment of acute myocardial infarction, prolong the life of patients with coronary heart disease, and improve the survival rate. In this study, 30 healthy adults are classified as the control group, and real-time three-dimensional echocardiography technology is used to observe the myocardial changes and characteristics of right ventricular morphology after acute myocardial infarction, which provides a theoretical basis for early clinical diagnosis and early intervention. The results show that the real-time three-dimensional echocardiography can provide more diagnostic information through the three-dimensional imaging of the cardiac structure and the real-time observation of the cardiac structures and their adjacent relations from any angle by combining the cutting and rotation of the image. Conventional examination methods such as two-dimensional echocardiography have a narrow time window for the detection of transient myocardial ischemia, which can clearly diagnose the ischemia in early stage, but its diagnostic ability in the late stage of ischemia is limited. When obtaining the cardiac full volume image within one cardiac cycle, echocardiography can quickly acquire dynamic images of ventricular volume without splicing and combine with the function of automatic delineation of endocardium of the 3d workstation to construct a real ventricular stereo image independent of the assumptions of the geometric model, so as to solve the inconvenience of the complex right ventricular space configuration and the obvious difference of its shape with the different load state. Therefore, as a new non-invasive imaging technique, it has unique advantages in accurate measurement of heart volume and evaluation of heart function.