Iranian Heart Journal

Iranian Heart Journal

The Utility of the Lorenz Plot in Assessing Electrocardiographic Waveforms in Type 2 Diabetes with Sinus Rhythm: A Preliminary Controlled Clinical Observation

Document Type : Original Article

Authors
Marwan salih Al-Nimer 1
Maryam Mohan Dawood 2
1 College of Medicine, University of Diyala, 32001 Baqubah, Iraq.
2 Department of Ultrasound and Radiology, Ishtar Institute of Medical Technology, 10016 Baghdad, Iraq.
Abstract
Background: Analysis of the Lorenz plot (LP) has been studied in tachyarrhythmias resulting from many causes. Patients with diabetes have abnormal electrocardiographic (ECG) findings related to prolonged QT intervals and ventricular repolarization, which are causes of ventricular arrhythmias. This preliminary controlled observational clinical study aimed to demonstrate the shape and pattern of LP analysis in patients with diabetes with normal sinus rhythm.

Methods: A total of 100 participants (42 healthy individuals and 58 patients with diabetes) were recruited from 2 diabetes centers in 2025. Characteristics of the participants and ECG records were obtained. Each record was analyzed by determining measurements related to different intervals and the LP up to 9 R-R(n) intervals.

Results: Significantly shorter R-R(n) intervals, QRS dispersion, and TQ intervals, and significantly prolonged P-R intervals, QRS duration, and QT and JT intervals were observed in patients with diabetes compared with healthy participants. The LP analysis revealed that the patterns and morphologies were comet and comet-club (in healthy participants) and torpedo and cigarette (in patients with diabetes), respectively. A significant positive correlation between the Tp-e/QTc value and R-R(n)+1 was observed.

Conclusions: Patients with diabetes have a distinct pattern and shape of the LP compared with healthy participants, and the R-R(n)+1 interval was significantly positively correlated with the Tp-e/QTc ratio. (Iranian Heart Journal 2026; 27(4): 40-49)
Keywords
Lorenz plot
sinus rhythm
diabetes mellitus
Tp-e/QTc
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Iranian Heart Journal
Volume 27, Issue 4
Autumn 2026
Pages 40-49