Assessment of Left Ventricular Function in Prediabetes Using Two-Dimensional Speckle Tracking Echocardiography

Abstract Background: Diabetes mellitus is one of the most important cardiovascular risk factors. The onset of type 2 diabetes mellitus is gradual, with nearly 70% of the patients progressing through prediabetic state which can persist for years. Multiple studies have shown prediabetes to be associated with increased risk of heart failure. Due to prolonged exposure to high glucose levels it has been supposed that prediabetes represents a state of continuous subclinical myocardial damage, which lead to left ventricular (LV) dysfunction and ultimately to heart failure. Speckle tracking echocardiography measured global longitudinal strain can detect subclinical LV dysfunction at an early stage. Aim of Study: Is to investigate the presence of subclinical LV dysfunction with comprehensive echocardiography includ-ing STE among asymptomatic prediabetic individuals and to study possible association between glycemic status and dif-ferent indices of LV systolic and diastolic function. Patients and Method: 90 subjects divided into 45 normo-tensive prediabetic subjects without known cardiovascular diseases and 45 age and sex matched normoglycemic, healthy subjectswere assessed by conventional echocardiography, TDE and 2-DSTE to measure global longitudinal strain of LV. Results: In prediabetic subjects, prolonged DT (p<0.007), higher E/e' ratio (p<0.006), higher lateral a' peak velocity (p<0.014), lower medial and lateral e'wave velocity (p<0.001, p<0.007), lower lateral s' wave peak velocity (p<0.0001) and medial e'/a' ratio (p<0.024),lower EF% (p<0.02); however still in the normal range, and lower GLS (p<0.0001) compared with controls. Among pre-DM group, several echocardiograph-ic measurements showed significant modest correlations with one or more of the 3 glycemic indices. There was significant correlation between all glycemic indices and GLS, with fasting plasma glucose (r=–0.42, p<0.0001), 2-h plasma glucose (r=–0.45, p<0.0001) and HbA1c (r=–0.57, p<0.0001), and E/e' ratio with fasting plasma glucose (r=–0.285, p<0.007), 2-h plasma glucose (r=–0.344, p<0.001) and HbA1c (r=–0.209, p<0.048). Conclusion: Prediabetes is associated with subclinical LV systolic and diastolic dysfunction with an association that exists between the severity of glycemia dysregulation and the extent of LV dysfunction. STE can detect early subclinical systolic longitudinal deformation abnormality before overt-impairment of indices of LV systolic function.