Abstract
BACKGROUND: In this study, we aimed to investigate the prognostic implications of lead aVR ST-segment elevation in an initial electrocardiogram (ECG) in patients diagnosed with acute coronary syndrome (ACS). Furthermore, we evaluated the association between electrocardiographic changes in lead aVR and objective measures such as angiographic findings and Syntax score. METHODS: This retrospective cohort study, conducted as a pilot study, encompassing both a retrospective cross-sectional analysis and a longitudinal follow-up, took place at Chamran Hospital from November 2017 to October 2019. A 6-month follow-up was conducted via phone interviews to assess patient outcomes. RESULTS: During the study period, there were 76 admissions with the final diagnosis of acute coronary syndrome and lead aVR ST-segment elevation on ECG. ARB intake and the severity of right coronary artery stenosis were significantly higher in patients with STE-aVR ≥1.5 mm. The clinical pathway analysis and 6-month follow-up outcomes concerning ST-segment changes in lead aVR did not reveal statistically significant differences in the distribution of various intervention strategies and clinical events. The overall ST-change was a significant risk factor for 6-month follow-up angiography (OR: 1.10; 95% CI: 1.002 to 1.213) and was also significantly associated with any stenosis in the RCA territory (OR: 1.10; 95% CI: 1.004 to 1.21). There was no significant association between ST-change and other follow-up hospital and angiography outcomes. CONCLUSION: The findings suggest that medication history, particularly with angiotensin receptor blockers, may shape the observed ST-segment changes in lead aVR. However, further investigation is needed to better understand the clinical implications of these trends.