Objective To assess left ventricular (LV) structure, LV function, left atrial (LA) structure and LA systolic function by using all the currently available echocardiographic methods in patients with type 2 diabetes mellitus (DM) or impaired glucose tolerance (IGT), with or without coronary artery disease (CAD).

Methods Four groups of patients were evaluated including 35 patients with type 2 DM complicated with chronic CAD, 26 patients with type 2 DM without CAD, 12 patients with IGT without CAD and 26 healthy controls. All the patients were underwent coronary angiography to diagnose or exclude significant CAD. Echocardiography was performed and a lot of M-mode, 2-DE, pulse wave Doppler and tissue Doppler imaging parameters were measured.

Results All the patients with diabetes or IGT had a normal LV systolic function. However, compared to the control subjects, Am, Aa and Em/Ea were significantly higher (p<0.05) while Em/Am, Ea and Ea/Aa were significantly lower (p<0.01) in diabetic patients without CAD. Am and Aa were significantly higher (p<0.01 and p<0.05, respectively) while Em/Am was significantly lower in patients with IGT. Moreover, in patients with type 2 DM or IGT and without CAD, LAVmaxI, LAVminI, LAFF and LAEF were significantly higher. The diabetic patients with CAD had significant higher LVMI, LAVmaxI and LAEF (92.25 g/m²±26.96 g/m² vs 82.85 g/m²±13.97 g/m², 31.66 ml/m²±7.05 ml/m² vs 27.45 ml/m²±7.19 ml/m², 42.38%±9.91% vs 36.46%±5.49%, all p<0.05) compare to those without CAD.

Conclusions LV diastolic dysfunction, LA dilatation and enhanced LAEF existed already before the occurrence of significant LV systolic dysfunction in patients with type 2 DM or IGT. Patients with diabetes and CAD had more severe LA structural and functional abnormalities. These findings suggests that LA structural and functional abnormalities might be the earliest signs of further cardiac damage in type 2 diabetic patients when significant CAD is developed.