Echocardiographic evaluation of the effect of poor blood glucose control on left ventricular function and ascending aorta elasticity.

Abstract

Type 2 diabetes mellitus (T2DM) is associated with high cardiovascular risk. Preclinical left ventricular (LV) dysfunction and subclinical arterial stiffness have been documented in patients with T2DM. The aims of this study were to investigate whether there were any differences in LV function and ascending aorta elasticity between T2DM patients with controlled [defined as glycosylated hemoglobin (HbA1c) <6.5%] and uncontrolled (HbA1c ≥6.5%) blood glucose. We studied 86 T2DM patients: 42 T2DM patients with controlled blood glucose (controlled T2DM group) and 44 T2DM patients with uncontrolled blood glucose (uncontrolled T2DM group), and 40 healthy subjects as control. They all underwent transthoracic echocardiography examination, LV systolic function was evaluated by global longitudinal strain (GLS) and LV diastolic function was defined as the ratio of the early diastolic transmitral flow velocity (E) to average mitral annular velocity (e¯). Ascending aorta inner diameters and brachial blood pressure were measured to calculate ascending aorta elastic parameters: compliance (C), distensibility (D), strain (S), stiffness index (SI), Peterson's elastic modulus (EM). Compared to control, T2DM patients had reduced GLS, increased E/e ̅ and impaired ascending aorta elasticity. Furthermore, LV function and ascending aorta elasticity were more severely damaged in uncontrolled T2DM group compared with controlled T2DM group. By Pearson correlation analysis, the level of HbA1c was independently associated with the parameters of the LV function and ascending aorta elasticity. T2DM can impair the LV myocardial function and ascending aorta elastic properties, which may be further impaired by poor blood glucose control.