ABNORMAL LEFT-VENTRICULAR DIASTOLIC FUNCTION DURING COLD PRESSOR TEST IN UNCOMPLICATED INSULIN-DEPENDENT DIABETES-MELLITUS

1. Insulin-dependent diabetes mellitus is a known risk factor for congestive heart failure and an early diastolic dysfunction has been described, In order to see if diabetes itself and not complications like hypertension, nephropathy or ischaemic heart disease can be considered responsible for the abnormal diastolic function of the left ventricle, 17 young patients with uncomplicated insulin-dependent diabetes mellitus and 12 control subjects were exposed to a cold presser test. 2. Blinded echo-Doppler examination was performed before and during the test, During basal conditions, left ventricular dimensions and volumes were smaller in diabetes and atrial contributions to left ventricular filling were increased. 3. During the cold presser test, isovolumic relaxation time increased, peak early filling velocity (E) decreased, E deceleration time decreased and atrial contribution (A) increased significantly in diabetes, while only A increased in the control group,A marked increase in left atrial ejection force was seen in diabetes only (P < 0.002). This difference was seen in spite of comparable reductions in mitral area and atrioventricular compliance in the two groups. 4. The hyperfunction of the left atrium in diabetes is hypothesized to be due to reduced size of the left ventricle combined with incipient autonomic neuropathy.