Comp Less Recognized ECG Changes Associated with Significant Ischemia, Concerning the Minnesota Coding System

Hatamzadeh, Hossein; Izadi-Moud, Azadeh; Salehi-Sangani, Pooria; Moohebati, Mohsen; Islampanah, Muhammad; Pourali, Ghazaleh; Yadollahi, Asal; Rezaeifard, Helia; Ferns, Gordon A; Saffar Soflaei, Sara; Ghaour-Mobarhan, Majid

doi:10.30483/rjm.2025.254652.1426

Comp Less Recognized ECG Changes Associated with Significant Ischemia, Concerning the Minnesota Coding System

Document Type : Original Article

Authors

¹ Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

² Department of Cardiovascular Diseases, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

³ Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

⁴ Heart and Vascular Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Cardiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

⁵ Metabolic Syndrome Research Center, Mashhad University of Medical Science, Mashhad, Iran

⁶ International UNESCO Center for Health-Related Basic Sciences and Human Nutrition, Mashhad University of Medical Sciences, Mashhad, Iran

⁷ Brighton and Sussex Medical School, Division of Medical Education, Brighton, UK

10.30483/rjm.2025.254652.1426

Abstract

Background: An electrocardiogram (ECG) is a commonly used, noninvasive, cost-effective tool widely available for diagnosing patients with coronary artery disease. It is associated with significant myocardial ischemia due to Coronary artery disease (CAD), which is associated with specific ECG changes.

Objectives: The goals were to determine less well-known ECG changes associated with significant ischemia and assess their potential value as early markers for diagnosing myocardial ischemia in patients with CAD.

Methods: Data were obtained from participants in the MASHAD cohort study. The characteristics obtained, including fasting blood glucose, lipid profile, history of diabetes mellitus, history of hypertension, and history of previous CVD, were recorded. A 12-lead ECG was also obtained for each subject and coded for specific ECG changes using Minnesota (MN) codes. Patients were divided into two groups based on MN coding for significant ischemia. A p-value less than 0.05 was considered significant.

Results: Out of 9035 coded ECGs,1276 (14.1%) had significant myocardial ischemia. After applying backward binary logistic regression, left- and right-axis deviations were significantly associated with significant ischemia (OR=2.482, p<0.001; OR=2.757, p=0.023, respectively). Left Ventricular (OR=2.171, p=0.020) and right ventricular hypertrophy (OR=5.747, p=0.004) showed significant associations. Other indicators, including minor T-wave abnormalities (OR=3.249, p<0.001), left anterior hemiblock (OR=4.711, p=0.001), and notched and widened P wave (OR=2.415, p<0.001), were also significantly associated with significant ischemia.

Conclusion: These findings suggest that the identified ECG changes may serve as novel indicators or associated markers of central ischemia. However, more longitudinal studies are needed to evaluate each of these abnormalities in patients with CAD.

Keywords

Acknowledgements: The authors would like to thank Mashhad University of Medical Sciences (MUMS).

Availability of data and materials: The data generated and analyzed during the current study are available from the corresponding author upon reasonable request. The data belongs to Mashhad University of Medical Sciences (MUMS).

Conflicts of interests: The authors declare no conflict of interest.

Consent for publication: Not applicable.

Ethics approval and consent to participate: The study was approved by the ethics committee of Mashhad University of Medical Sciences (MUMS) under the approval code IR.MUMS.MEDICAL.REC.1399.783, following the principles of the Helsinki Declaration for medical research involving human subjects.

Financial disclosure: No funding was received to conduct this study.

Author contributions: Study concept and design: MG and HE; data collection: SSS, AI, HR, and AY; analysis and interpretation of data: SSS; drafting of the manuscript and critical revision: HH, PS, MI, AI, SSS, and GAF. All authors reviewed and approved the final version of the manuscript.

Open Access Policy: This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/

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Comp Less Recognized ECG Changes Associated with Significant Ischemia, Concerning the Minnesota Coding System

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Volume 14, Issue 1
January 2026
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Comp Less Recognized ECG Changes Associated with Significant Ischemia, Concerning the Minnesota Coding System

References

Volume 14, Issue 1January 2026Pages 1-13

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Volume 14, Issue 1
January 2026
Pages 1-13