Echocardiographic Evaluation of the Effect of Poor Blood Glucose Control on Left Ventricular Function and Ascending Aorta Elasticity

Abstract Background: 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 was any differences in LV function and ascending aorta elasticity between T2DM patients with controlled [defined as glycosylated hemoglobin (HbA 1c ) <6.5%] and uncontrolled (HbA 1c ≥6.5%) blood glucose. Methods: We studied 86 T2DM patients with preserved LV ejection fraction (LVEF) whom be divided into two groups: 42 T2DM patients with controlled blood glucose (controlled T2DM group) and 44 T2DM patients with uncontrolled blood glucose (uncontrolled T2DM group), and 40 age- and gender-matched healthy subjects as controls. They all underwent transthoracic echocardiography examination, LV systolic function was evaluated by global longitudinal strain (GLS) measured using three-dimensional speckle-tracking echocardiography. LV diastolic function was defined as the ratio of the early diastolic transmitral flow velocities (E) to average mitral annular velocity (ȇ), and E/ȇ >14 was determined as abnormal. 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). Results: Compared to controls, patients with T2DM had reduced GLS, increased E/ȇ 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 HbA 1c was independently associated with the parameters of the LV function and ascending aorta elasticity. Conclusions: T2DM can impair LV myocardial function and ascending aorta elastic properties. Poor blood glucose control can lead to further damage to LV function and elasticity of the ascending aorta.