Lead aVR ST-Segment Elevation as a Marker for Left Main Coronary Artery Disease in Acute Coronary Syndrome Patients

Background: Coronary artery disease (CAD) is a leading cause of death globally, including in Pakistan. Accurate and timely identification of severe left main coronary artery disease (LM-CAD) in patients with acute coronary syndrome (ACS) is crucial for improving outcomes. ST-segment elevation in lead aVR on electrocardiogram (ECG) has been proposed as a potential marker for LM-CAD. Objective: The study aimed to ascertain the prevalence of left main coronary artery disease in acute coronary syndrome patients exhibiting ST-segment elevation in lead aVR and to evaluate the diagnostic utility of this ECG finding. Methods: This cross-sectional study was conducted at the Department of Cardiology, Hayatabad Medical Complex, Peshawar, KPK, Pakistan, from April 2023 to May 2024. A total of 125 patients aged 18-75 years with ST-segment elevation of >0.5mm in lead aVR were enrolled. Exclusion criteria included chronic kidney disease, severe anemia, dextrocardia, history of circulatory collapse, low ejection fraction, and prior bypass grafting. Demographic and clinical data were collected, and all patients underwent coronary angiography. Data analysis was performed using SPSS version 25.0. Quantitative variables were presented as mean ± standard deviation, while qualitative variables were expressed as frequencies and percentages. The chi-square test was used to find associations, with a p-value <0.05 considered significant. The study followed ethical guidelines, including informed consent and institutional ethical board approval. Results: The cohort included 70.4% males and 29.6% females, with a mean age of 55.76 ± 6.5 years. Among the patients, 81.6% had LM-CAD. Significant associations were found between LM-CAD and smoking (P = 0.017) as well as obesity (P = 0.003). No significant associations were observed with age (P = 0.825) or gender (P = 0.764). Among the types of ACS, NSTEMI patients had the highest LM-CAD prevalence (48%), followed by STEMI (22.4%) and unstable angina (11.2%), with a significant association between unstable angina and LM-CAD (P = 0.048). Conclusion: ST-segment elevation in lead aVR is a reliable indicator of left main coronary artery disease in patients presenting with acute coronary syndrome. Major cardiovascular risk factors such as smoking and obesity showed strong correlations with this ECG finding. Incorporating lead aVR analysis into routine ECG evaluations can enhance diagnostic accuracy and facilitate early therapeutic decisions, potentially improving patient outcomes.