Introduction
DM is a systemic metabolic disorder, and more than 70% of diabetic
patients develop coronary heart disease (CHD), which exhibits a wider
range and faster progression of coronary artery disease compared to
non-diabetic individuals. The main lesions in CHD occur in the
epicardium, whereas in DM, the primary lesions involve the myocardium
and microvasculature. When both conditions coexist, the aforementioned
lesions may be more extensive and severe. Clinical observations have
shown that DM patients with concomitant CHD have a higher prevalence and
severity of multi-vessel and diffuse coronary lesions compared to
non-diabetic patients[1-2]
Studies have confirmed that after acute myocardial infarction (AMI), the
region of RWMA comprises not only necrotic myocardium but also viable
myocardium, including stunned myocardium and hibernating
myocardium[3-4]. So far, there are three main
approaches used to identify viable myocardium[4]:
(1) Assessment of myocardial cellular metabolism, including oxidative
metabolism, glucose metabolism, and fatty acid metabolism; (2)
Evaluation of myocardial perfusion; (3) Monitoring of myocardial
contractile reserve. Among these, dobutamine stress echocardiography
(DSE) is internationally recognized as the standard method for
monitoring myocardial contractile reserve and is widely employed.
At present, STE-LDDSE offers significant advantages over traditional
methods for assessing viable myocardium[5-8]. It
mainly tracks the speckles of high-frame-rate two-dimensional images
frame by frame, allowing for the calculation and delineation of
myocardial motion velocity and deformation. By observing myocardial
motion trajectories, it accurately measures myocardial fiber motion
strain, strain rate, and rotation angles. Due to its angle-independent
nature, STE can provide more accurate assessments of local and global
myocardial function, making it highly valuable for detecting viable
myocardium. The combination of STE and LDDSE further enhances the
sensitivity and specificity, maximizing the detection of viable
myocardium[9-12].