Early diastolic impairment of diabetic heart: the significance of right ventricle.

BACKGROUND: Left ventricular diastolic dysfunction represents the earliest preclinical manifestation of diabetic cardiomyopathy. Right ventricular function has not been studied in depth yet in diabetic patients, although the right ventricle has an important contribution to the overall cardiac function. This study was designed to assess diastolic and systolic ventricular function in both ventricles, in patients with type 1 diabetes, free from coronary artery disease and hypertension.
METHODS: We studied 66 type 1 diabetic patients and 66 age- and sex-matched normal subjects by conventional and tissue Doppler echocardiography. A possible correlation was examined for age, diabetes duration and echocardiographic measurements of left ventricular and right ventricular functions with univariate analysis.
RESULTS: Type 1 diabetic patients were found to have impaired diastolic function in both ventricles with either conventional or tissue Doppler echocardiography. On the contrary, systolic function in both ventricles was preserved in our diabetic population. The measured indexes showed an expected correlation with age and diabetes duration except from systolic velocity in tricuspid annulus determined by color tissue Doppler. Moreover, significant correlations were found among parameters of left and right ventricular function.
CONCLUSIONS: Patients with type 1 diabetes mellitus have impaired diastolic function, and particularly relaxation, in both ventricles before the development of myocardial systolic dysfunction. These alterations in myocardial function may be attributed to ventricular interdependence as well as to the uniform effect of diabetes to cardiac function.