Atrial artery involvement in myocardial infarction and new-onset atrial fibrillation: two-center retrospective cohort study

Introduction: Predicting the development of new-onset atrial fibrillation in patients with acute myocardial infarction is challenging, and the search for potential predictors continues. Recent evidence suggests that atherosclerotic or embolic lesions inthe arteries supplying the atria may influence the development of atrial fibrillation. Objective: To assess the incidence of lesions in the arteries supplying the atria in patients with acute primary myocardial infarction who develop new-onset atrial fibrillation.Methods: This two-center retrospective cohort study included 141 patients hospitalized in cardiology departments between 2020 and 2023 with acute myocardial infarction and new-onset atrial fibrillation. The coronary angiography protocol additionallyincluded examination of the arteries supplying the atria and assessment of their involvement in areas of acute or chronic ischemia. Results: Right-dominant coronary circulation was the predominant pattern, observed in 125 (88.7%) patients. In 46 (32.6%) patients, the atrial arteries were not involved in an area of acute or chronic ischemia; 34 (24.1%) patients had involvement or lesions ofone atrial artery; two atrial arteries were located in an ischemic area in 35 (24.8%) patients; combined involvement of three atrial arteries was observed in 17 (12.1%) patients; and all four atrial arteries examined were located in an area of acute or chronic ischemia in 9 (6.4%) patients. The sinus node artery was normal in 123 (84.8%) patients. The atrioventricular nodal artery was located in an area of acute ischemia in 38 (27.0%) cases and in an area of chronic ischemia in 29 (20.6%) cases; one additional patient (0.7%) had 90–99%stenosis of the artery itself. The right interatrial artery was located in an area of acute ischemia in 25 (17.7%) cases and in an area of chronic ischemia in 30 (21.3%) patients; 90–99% stenosis of this artery was detected in 11 (7.8%) additional patients. The left interatrialartery was normal or anatomically undeveloped in 106 (75.2%) patients, located in an area of acute ischemia in 8 (7.1%) patients, and located in an area of chronic ischemia in 24 (17.0%) patients; one (0.7%) patient had 90–99% stenosis. Conclusion: In 67.4% of cases, the development of new-onset atrial fibrillation in patients with myocardial infarction was associated with acute or chronic disease of the atrial arteries. In 95% of patients with an infarction-related right coronary artery and new-onset atrial fibrillation, the atrial arteries – the atrioventricular nodal artery and the right interatrial artery – were located in an area of acute or chronic ischemia. Received 22 April 2026. Revised 19 May 2026. Accepted 14 July 2026. Informed consentThe patient’s informed consent to use the records for medical purposes is obtained. FundingThe study did not have sponsorship. Conflict of interestThe authors declare no conflict of interest. Contribution of the authorsConception and study design: D.A. Shebonkina, L.V. Shekhovtsova, T.V. Kislukhin, D.V. Duplyakov Data collection and analysis: D.A. Shebonkina, L.V. Shekhovtsova, M.S. Vasilyeva, A.L. Titov, M.I. Boyarintsev, I.R. Vasilenok Statistical analysis: D.A. Shebonkina Drafting the article: D.A. Shebonkina Critical revision of the article: D.A. Shebonkina, D.V. Duplyakov Final approval of the version to be published: all authors