Association between subclinical left ventricular systolic dysfunction and glycemic control in asymptomatic type 2 diabetic patients with preserved left ventricular function.

BACKGROUND

Type 2 diabetes is strongly associated with the occurrence of cardiovascular diseases, especially heart failure. Some studies have suggested that subclinical systolic dysfunction as assessed by tissue Doppler imaging (TDI) is already present in uncomplicated diabetic patients with normal left ventricular ejection fraction (LVEF). Considering the importance of this aspect, the aim of this cross-sectional study was to examine the relationship between glycated hemoglobin and mean s' wave velocity (a reliable measure of early LV systolic dysfunction) in a cohort of type 2 diabetic outpatients with preserved LVEF and without ischemic heart disease.

METHODS

Forty-four male patients with newly diagnosed and 172 male patients with established type 2 diabetes were recruited for this cross-sectional study. All patients were evaluated with a transthoracic echocardiographic Doppler. The statistical analysis was conducted by a linear multivariate regression analysis, including several potential confounders.

RESULTS

The mean values of mean s' wave velocity were lower in patients with a worse glycemic control and progressively decreased across the quartiles of glycated hemoglobin. The multivariate linear regression analysis showed that mean s' wave velocity was inversely and independently associated with glycated hemoglobin (standardized beta coefficient -0.178; p = 0.043) after adjustment for age, duration of diabetes, body mass index, pulse pressure, estimated glomerular filtration rate, microvascular complication status, and indexed cardiac mass.

CONCLUSIONS

These results suggest that s' wave velocity, as evaluated by TDI echocardiography, was an early marker of systolic dysfunction in type 2 diabetic patients with preserved LVEF and without prior ischemic heart disease. Moreover, early systolic dysfunction was independently associated with poor glycemic control in these patients. Future studies are needed to elucidate the pathogenic role of chronic hyperglycemia in the development of early LV systolic dysfunction.