SIGNAL-AVERAGED ELECTROCARDIOGRAM IN PATIENTS WITH INSULIN-DEPENDENT (TYPE-1) DIABETES-MELLITUS WITH AND WITHOUT DIABETIC NEUROPATHY

The purpose of this study was to investigate the presence of ventricul ar late potentials derived from signal-averaged ECG in patients with I DDM with and without diabetic neuropathy. Eighty patients with IDDM bu t without evidence of cardiac disease and 80 age-matched healthy contr ol subjects were investigated. The corrected QT interval was measured from the standard surface electrocardiogram. Ventricular late potentia ls were derived from signal-averaged electrocardiogram. Out of the 80 diabetic patients, 20 had an autonomic neuropathy, 20 had an isolated peripheral neuropathy, and 40 had no symptoms of neuropathy. The corre cted QT interval was significantly prolonged in patients with an auton omic neuropathy as compared with the control group (436 +/- 23 ms(.5) vs 384 +/- 23 ms(.5), p < 0.001). In the other patient groups there wa s no significant prolongation of the corrected QT interval. Ventricula r late potentials were present in 3 diabetic patients with an isolated peripheral neuropathy and in 1 control subject (NS). No diabetic pati ent with an autonomic neuropathy had ventricular late potentials. Our data did not indicate an increased incidence of ventricular late poten tials derived from signal-averaged electrocardiogram in diabetic patie nts independent of a coexisting diabetic neuropathy or a prolonged cor rected QT interval. (C) 1997 by John Wiley & Sons, Ltd.