ABC | Volume 114, Nº2, February 2020

Original Article Inanır et al. Arrhythmia predictors in type 1 diabetes mellitus Arq Bras Cardiol. 2020; 114(2):275-280 Limitations Manual calculation of measurements instead of computer- assisted calculationsmay be a limitation. Automatedmeasurement systems have been developed for QT measurement, but some problems currently exist with these systems. 38 Manual identification of T-end is also problematic, cardiologist- dependent, and poorly reproducible. Therefore, automated methods may be preferrable. 39 Long‑term ambulatory ECG monitorization methods might be valuable for documenting the association between the surface ECG parameters studied and arrhythmias. The number of patients in our study was relatively small. A larger patient population would provide more precise results. Association between ECG parameters may be evaluated along with other potential mechanisms for sudden death, such as autonomic dysfunction and fibrosis detected by magnetic resonance imaging. Lack of clinical follow up of the patients regarding arrhythmias and sudden death is another important limitation. Conclusions Previous studies have shown that QTc and QTdc prolongation is important in terms of malignant ventricular arrhythmias in patients with T1DM. 40 However, Tp-e and JTc intervals and Tp-e/QT and Tp-e/QTc ratios had not previously been measured in patients with T1DM. This study shows that these relatively new repolarization indices and potential electrocardiographic predictors of ventricular arrhythmias are significantly increased in T1DM. Further studies are needed to confirm our results. We hope that clinical significance of this finding for the prediction of malignant arrhythmias will be evaluated in future long-term follow-up and large-scale prospective studies. Author contributions Conception and design of the research, Analysis and interpretation of the data, Statistical analysis andWriting of the manuscript: Inanır M, Gunes Y, Sincer I, Erdal E; Acquisition of data: Inanır M, Gunes Y; Obtaining financing: Inanır M, Gunes Y, Erdal E; Critical revision of the manuscript for intellectual content: Inanır M, Gunes Y. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associatedwith any thesis or dissertationwork. Ethics approval and consent to participate This study was approved by the Ethics Committee of the Abant Izzet Baysal UniversityHospital under the protocol number 2018‑216. All theprocedures in this studywere in accordancewith the1975Helsinki Declaration, updated in2013. Informed consent was obtained from all participants included in the study. 1. 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