[Parameters of heart rhythm variability and QT-interval in patients with ischemic heart disease and type 2 diabetes].

We studied parameters of heart rhythm variability and QT intervals in 141 patients (mean age 52.4 +/- 7.3 years) with unstable angina and acute myocardial infarction; 101 of these patients (71.6%) had type 2 diabetes. We found that in patients with diabetes parameters RRNN, LF and LF/HF were significantly lower. In patients with diabetes and risk of microangiopathy lowering of LF was maximal and correlated with elevation of glycosylated hemoglobin. In patients with diabetes and neuropathy significant reduction of power in HF range and increase of maximal corrected QT-interval value were observed. It is possible, that in patients with ischemic heart disease type 2 diabetes causes decrease of tone of vegetative nervous system mainly due to activity of parasympathetic part and this is accompanied by impaired repolarization of cardiac ventricles.