Abstract Vascular endothelial dysfunction, accelerated
thickening of arterial intima, and changes in ventricular
functions contribute to increased cardiovascular morbidity
in type 1 diabetes mellitus (T1DM). This study aimed to
investigate the functional-structural changes in the arteries
and myocardium together with affection of highly sensitive
C-reactive protein (hsCRP), circulating endothelial cells
(CECs), and vitamin C levels in children with T1DM. Also,
to test the association with early atherosclerotic changes. The
study included 30 children with a diagnosis of T1DMand 30
healthy subjects matched by sex, age, and body mass index.
Serum lipids, HbA1c, hsCRP, vitamin C, and CECs were
detected. Corrected QT interval (QTc), cardiac dimensions,
and left ventricular (LV) functions were assessed using
conventional echocardiography. Noninvasive ultrasound
was used to measure brachial artery flow-mediated dilation
(FMD) responses and carotid intima-media thickness (IMT).
The QTc interval was significantly higher in the diabetic
patients than in the control subjects (P.001). The findings
showed LV diastolic dysfunction as reflected by significantly
lower early peak flow velocity, decreased E/
A ratio, increased early filling deceleration time (DcT), and
prolonged isovolumic relaxation time (IVRT) (P.001for each). The children with diabetes had a significantly
lower FMD response, increased IMT, lower vitamin C level,
higher hsCRP, and higher CEC compared with the control
subjects (P.001 for each). A positive correlation
between CEC and HbA1c was found (P = 0.004). An
alteration in myocardial function and endothelial dysfunction
may begin early with the association of early atherosclerotic
changes. These changes are accelerated when
glycemic control is poor. The authors recommend early and
close observation of children with diabetes for any alterations
in cardiac and vascular endothelial function. Vitamin C
supplementation may reduce the risk of complications.