Objective:To quantitatively evaluate left ventricular myocardial work in patients with type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD) by pressure strain loop (PSL) technique.Methods:A total of 103 T2DM patients diagnosed at the Heping Hospital Affiliated to Changzhi Medical College from April 2022 to May 2023 were selected. They were divided into three groups based on their fatty liver ultrasound findings: group A (34 cases without NAFLD), group B (37 cases with mild NAFLD), and group C (32 cases with moderate to severe NAFLD). All patients underwent routine echocardiography, which measured the end diastolic left ventricular diameter (LVIDd), end systolic left ventricular diameter (LVIDs), end diastolic interventricular septum (IVSTd), left ventricular posterior wall thickness (LVPWTd), and end systolic left atrial diameter (LAD). The biplane Simpson method was used to measure left ventricular ejection fraction (LVEF), end diastolic left ventricular volume (LVEDV), and end systolic left ventricular volume (LVESV). PSL technology was applied to analyze the overall longitudinal strain (GLS), global work index (GWI), global effective work (GCW), global ineffective work (GWW), and overall work efficiency (GWE) of the left ventricular myocardium. We compared the conventional echocardiography parameters and myocardial work parameters among three groups, and analyzed the correlation between myocardial work parameters and GLS and glycosylated hemoglobin (HbA 1c). Results:The differences in body mass index (BMI), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) between group B and group A were statistically significant (all P<0.05); There was a statistically significant difference in BMI, HbA 1c, and low density lipoprotein cholesterol (LDL-C) between group C and group B (all P<0.001); The differences in BMI, HbA 1c, ALT, AST, triglyceride (TC), high density lipoprotein cholesterol (HDL-C), and LDL-C between group C and group A were statistically significant (all P<0.05). The GWI and GCW in group B were lower than those in group A (all P<0.05), while the absolute GLS, GCW, GWI, and GWE in group C were lower than those in group A, and GWW was higher than those in group A (all P<0.05); The absolute values of GLS, GCW, GWI, and GWE in group C were lower than those in group B ( P<0.05). The correlation analysis results showed that GLS and HbA 1c were negatively correlated with GCW and GWI ( r=-0.571, -0.533, -0.273, -0.223, P<0.05). Conclusions:PSL technology can quantitatively evaluate left ventricular myocardial work in patients with T2DM combined with NAFLD, and can detect early impairment of left ventricular systolic function in patients. It has clinical reference value in evaluating overall and local cardiac function.