[Diabetic cardiomyopathy]

Type I and type II diabetes is associated with increased cardiovascular complications, the most common of which are ischaemic cardiomyopathy and left ventricular dysfunction. The existence of an independent disease, diabetic cardiomyopathy, was suggested by initial anatomic studies, experimental models, and, more recently, by epidemiological studies. The exact cause of this ventricular dysfunction is not known: several mechanisms have been proposed, such as metabolic abnormalities of glucose transport, cellular overload in fatty acid metabolites, alteration of calcium uptake by the sarcoplasmic reticulum leading to cellular calcium overload, coronary microangiopathy, structural collagen abnormalities, interstitial and perivascular fibrosis or the presence of an autonomic neuropathy. The condition is characterised by abnormal left ventricular filling suggesting poor compliance or prolongation of left ventricular relaxation. Left ventricular systolic function is usually normal at rest but abnormally decreased on effort. The value of strict metabolic control and the place of drug therapy, especially calcium antagonists which oppose cellular calcium overload, has yet to be established. The natural history of diabetic cardiomyopathy should be defined by clinical studies taking care to differentiate it from the cardiovascular consequences of hypertension or obesity which aggravate or stimulate this condition.