The additive effects of kidney dysfunction on left ventricular function and strain in type 2 diabetes mellitus patients verified by cardiac magnetic resonance imaging

BACKGROUND Patients with type 2 diabetes mellitus (T2DM) are susceptible to coexisted with chronic kidney disease (CKD), which may increase cardiovascular mortality in these patients. The present study aimed to verify whether CKD aggravates the deterioration of left ventricular (LV) myocardial strain in T2DM patients and to explore the risk factors associated with LV strain. MATERIALS AND METHODS In total, 105 T2DM patients and 52 healthy individuals were included and underwent cardiac magnetic resonance examination. Patients were divided into the following two groups: T2DM with CKD (n = 33) and T2DM without CKD (n = 72). The baseline clinical and biochemical indices were obtained from hospital records before the cardiac magnetic resonance scan. Cine sequences, including long-axis views (2-chamber and 4-chamber) and short-axis views, were acquired. LV function and global strain parameters were measured based on cine sequences and compared among three groups. Pearson's analysis was performed to investigate the correlation between LV strain parameters and clinical indices. Multiple linear regression analysis was used to identify the independent indicators of LV strain. RESULTS Compared with normal controls, T2DM patients without CKD had a significantly decreased magnitude of peak strain (PS; radial), peak systolic strain rate (radial), and peak diastolic strain rate (radial and circumferential) (all P < 0.05). Furthermore, T2DM patients with CKD displayed markedly lower magnitudes of PS (radial, circumferential, and longitudinal) and peak diastolic strain rate (circumferential and longitudinal) than both normal controls and T2DM patients without CKD (all P < 0.05). The eGFR was positively associated with the magnitude of PS (R = radial, 0.392; circumferential, 0.436; longitudinal, 0.556), while uric acid was negatively associated with the magnitude of PS (R = radial, - 0.361; circumferential, - 0.391; longitudinal, - 0.460) (all P < 0.001). Multivariable linear regression indicated that the magnitude of PS was independently associated with eGFR (β = radial, 0.314; circumferential, 0.292; longitudinal, 0.500) and uric acid (β = radial, - 0.239; circumferential, - 0.211; longitudinal, - 0.238) (all P < 0.05). CONCLUSIONS Kidney dysfunction may aggravate the deterioration of LV strain in T2DM patients. LV strain is positively associated with the estimated glomerular filtration rate and negatively associated with uric acid, which may be independent risk factors for predicting reduction of LV strain.