Endocrine Abstracts

Background and aims: Mortality rate from cardiovascular disease (CV) including sudden death (SD) is pronounced in type 2 diabetic (T2DM) patients with cardiac autonomic neuropathy (CAN) and/or complex ventricular arrhythmias (CVA). Early repolarization (ER) is also considered to be a significant risk factor for SD. The aim of the study was to evaluation the relation between CAN, CVA and ER in T2DM patients.

Materials and methods: Participants were 44 T2DM patients (24m/20f, mean age 56.9±7.3 years) with ER pattern (Gr.1) at the surface ECG defined as a J-point elevation of at least 0.1 mV in at least two leads I,II,III,avF,avL,V4,V5 or V6, when slurring of the terminal part of QRS was associated with an elevation of ST segment. As controls (Gr.2) 35 sex, age and diabetes duration matched patients were selected. In all patients 24 h Holter ECG was performed.

Results: CVA, such as paired ventricular extrasystoles, episodes of ventricular tachycardia (VT) were more frequently registered in Gr.1 (43.2 vs 34.3%), while frequent supraventricular extrasystoles were more often observed in Gr. 2 (37.1 vs 34%), though this difference was not significant. Heart rate variability (HRV) parameters SDNN (0.091±0.023 vs 0.118±0.029, P=0.000) and triangular index (25.4±6.3 vs 33.6±8.1 P=0.000) were significantly lower in Gr 1.

Conclusion: CVA were more frequently observed in T2DM patients with ER. HRV parameters were lower in patients with ER. Increased risk of sudden cardiac death in T2DM patients may be associated with repolarization abnormalities due to cardiac autonomy neuropathy that predisposes to fatal ventricular arrhythmias. Further studies are required in order to assess the role of cardiac autonomy neuropathy in the development of repolarization abnormalities in T2DM patients.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.