The relationship between heart rate variability and left ventricular layer-specific deformation in uncomplicated diabetic patients.

ABSTRACT

The aim of this study was to investigate heart rate variability (HRV) and left ventricular (LV) remodeling in uncomplicated diabetic patients. Furthermore, we sought to investigate the association between HRV indices and LV structural, functional and mechanical parameters. This cross-sectional study included 50 uncomplicated patients with type 2 diabetes and 40 healthy controls without cardiovascular risk factors. All study subjects underwent 24-h Holter monitoring, laboratory analyses and complete two-dimensional echocardiography examination (2DE). LV structure and diastolic function were significantly deteriorated in the diabetic patients comparing with the controls. LV global longitudinal, circumferential and radial strains were significantly reduced in the diabetic group. LV endocardial, mid-miocardial and epicardial longitudinal and circumferential strains were significantly decreased, whereas LV twist was significantly increased, in the diabetic patients; 24-h, daytime and nighttime heart rates were higher in the diabetic patients. All parameters of time and frequency domain of HRV were reduced in the diabetic subjects. LV mass index, mitral E/e' ratio and 2DE LV endocardial and mid-miocardial longitudinal and circumferential strains correlated with HRV parameters. A multivariate regression analysis showed that E/e' ratio and 2DE LV layer-specific strains were associated with HRV parameters independently of age, BMI, systolic blood pressure and LV mass index. HRV and LV mechanics are significantly deteriorated in uncomplicated diabetic individuals. Parameters of LV remodeling are independently associated with HRV indices, which could indicate the importance of HRV determination in diabetics.