Cardiomyopathy in childhood diabetes mellitus: incidence, time of onset, and relation to metabolic control.

Cardiac function was evaluated using computer-assisted analysis of M-mode echocardiograms in 36 patients with onset of type I diabetes (insulin-dependent diabetes) in childhood. None of the patients had clinical evidence for cardiovascular disease or microvascular disease. An impairment of diastolic function was observed in the older patients with long-standing diabetes. The time between minimal cavity dimension and mitral valve opening was significantly prolonged (P less than 0.005), while the change of dimension in this time period and the change of dimension with rapid diastolic filling were normal. Although fractional shortening as a parameter of systolic function was normal in the diabetics, fractional shortening was inversely related to the mean HbA1 averaged over the last two years, reflecting the status of long-term metabolic control (P less than 0.0008). The time between minimum cavity dimension and mitral opening was also related to the mean HbA1 averaged over the last two years (P less than 0.0011). It is concluded that, with time, alterations of both systolic and diastolic function develop in children with type I diabetes. Their severity depends on the quality of metabolic control.