Hyperlipidemia increases the risk of atherosclerotic cardiovascular disease (ASCVD), a leading cause of morbidity and mortality among patients with type 2 diabetes mellitus (T2DM). Non-traditional lipid parameters show strong performance in T2DM risk assessment and prediction and are closely associated with ASCVD. Layer-specific strain imaging based on two-dimensional speckle-tracking imaging (2D-STI) differentiates myocardial layers and segments, providing additional information on myocardial motion.

To evaluate structural and functional changes of the left ventricle (LV) in patients with T2DM and hyperlipidemia using layer-specific strain imaging in combination with non-traditional lipid parameters.

A total of 100 patients with T2DM and normal left ventricular ejection fraction (LVEF) who were hospitalized in the Department of Endocrinology at Yichang Central People's Hospital between January 2021 and June 2023 were included, 50 of whom had hyperlipidemia. An additional 50 age- and sex-matched healthy individuals served as controls. Patients were categorized into a T2DM group (n=50) and a T2DM with hyperlipidemia group (n=50); healthy participants formed the control group (n=50). Baseline data were collected, and nontraditional lipid parameters were calculated based on traditional lipid profiles. Echocardiographic results were gathered; software was utilized to calculate left ventricular global longitudinal strain (GLS) and global circumferential strain (GCS). Values for subendocardial, mid-myocardial, and subepicardial longitudinal strain (GLSendo, GLSmid, GLSepi) as well as subendocardial, mid-myocardial, and subepicardial circumferential strain (GCSendo, GCSmid, GCSepi) were derived. The differences between subendocardial and subepicardial longitudinal strain (ΔGLS) and between subendocardial and subepicardial circumferential strain (ΔGCS) were also calculated. Correlations between nontraditional lipid parameters and LVEF were assessed using Pearson or Spearman rank correlation analysis. Multivariable hierarchical regression analysis was performed to identify factors associated with left ventricular systolic function in patients with T2DM and hyperlipidemia.

Compared with the control group, the T2DM group had higher SBP, DBP, FPG, HbA_1c, non-HDL-C, non-HDL-C/HDL-C ratio, and LCI (all P<0.05). The T2DM with hyperlipidemia group had higher SBP, DBP, FPG, HbA_1c, TC, TG, LDL-C, AIP, CRI, non-HDL-C/HDL-C ratio, and LCI than the control group (all P<0.05). Compared with the T2DM group, the T2DM with hyperlipidemia group had higher TC, TG, LDL-C, AIP, CRI, RLP-C, non-HDL-C, and LCI (all P<0.05). Echocardiographic findings showed that LAD was higher, whereas LVEF and the E/A ratio were lower, in both the T2DM and T2DM with hyperlipidemia groups than in the control group. The E/e' ratio was higher in the T2DM group than in the control group (P<0.05). LVPW also differed significantly among the three groups (P<0.05). Strain analysis showed that GLS and GCS were lower and peak strain dispersion (PSD) was higher in both the T2DM and T2DM with hyperlipidemia groups than in the control group (P<0.05). GLSendo, GLSmid, GLSepi, GCSendo, GCSmid, GCSepi, and ΔGCS were reduced in both T2DM groups compared with controls; moreover, GLSendo, GLSmid, GLSepi, GCSendo, GCSmid, ΔGLS, and ΔGCS were lower in the T2DM with hyperlipidemia group than in the T2DM group (all P<0.05). In patients with T2DM and hyperlipidemia, LVEF correlated negatively with AIP, CRI, RLP-C, non-HDL-C, the non-HDL-C/HDL-C ratio, and LCI (all P<0.05). In multivariable hierarchical regression, LCI was independently and negatively associated with LVEF (β= -0.564, P=0.034), whereas GLSendo was positively associated with LVEF (β=0.807, P=0.006); the model including both variables provided the best fit.

Layer-specific strain imaging enables layer-targeted assessment of LV myocardial mechanics and detects early impairment of LV systolic function in patients with T2DM and hyperlipidemia, even when conventional LVEF is preserved. The combination of GLSendo and nontraditional lipid parameters showed high diagnostic value for detecting impaired left ventricular systolic function in patients with T2DM and hyperlipidemia.