Echocardiographic study of myocardial work in patients with type 2 diabetes mellitus

BACKGROUND: A noninvasive left ventricular (LV) pressure-strain loop (PSL) provides a new method to quantify myocardial work (MW) by combining global longitudinal strain (GLS) and LV pressure, which exerts potential advantages over traditional GLS. We studied the LV PSL and MW in patients with type 2 diabetes mellitus (T2DM). METHODS: This cross-sectional study included 201 subjects (54 healthy controls and 147 T2DM patients) who underwent complete two-dimensional echocardiography (2DE), including 2D speckle-tracking echocardiography (STE), as well as brachial artery pulse pressure measurement. The PSL was used to determine the global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) of all study participants. The association between T2DM and LV function was evaluated according to these MW indices. RESULTS: The GLS was significantly lower in the T2DM group than in the control group (P < 0.001), indicating that the LV myocardium had been damaged, although the LV ejection fraction (LVEF) was still normal. The GWI and GWE were decreased (P = 0.022) and the GWW was increased (P < 0.001) in diabetic patients compared with controls, but the GCW was comparable in the two groups (P = 0.160). In all diabetic patients, age, body mass index, systolic blood pressure, smoking history, and LVEF were correlated with GWI, GWW and GWE. CONCLUSIONS: The use of LV PSL is a novel noninvasive technique that could help to depict the relationship between LV myocardial damage and MW in patients with T2DM.