Ecg Features of Cardiac Autonomic Neuropathy In Patients With Type 2 Diabetes Mellitus

Abstract

IntroductionCardiac autonomic neuropathy (CAD) is associated with a poor cardiac prognosis, particularly with an increased risk of sudden death in diabetic patients. A lengthening of the QT interval and alteration of the QT dispersion have been reported in patients with diabetic CAD as well as increased sympathetic activity confirmed by the heart rate variability (HRV) assessment. Material and MethodsWe conducted a randomized study: 77 patients were enrolled in the Sumy Region Affair Hospital, among them 46 had type 2 diabetes mellitus (DM) for 5 years and longer (group A), 31 had normal glucose profile, history of DM was absent (group B). Our patients have been subjected to physical examination, blood tests (glucose, HbA1c, lipid profile), 12-lead ECG with HRV measure. The authors had full access and take responsibility for the integrity of the data. ResultsIt was detected that in patients with DM QTc interval values were close to the upper limits (461.5±26.61ms). The QTc averages of normal-to-normal (NN) intervals (SDANN), root mean square differences of successive NN intervals (RMSSD) and low-frequency (LF) – high-frequency (HF) power ratio were significantly higher in patients with DM (p<0.05). LF/HF was statistically linked to the increase of HbA1c and decrease of magnesium level. It was detected that changes could be improved by the glucose level control and treatment with magnesium supplements 100 mg per day for 30 days (p<0.05). ConclusionCAD is associated with QT prolongation and HRV disturbances. Further research of possible long-term consequences and approaches to their correction is required.