A Simple Non-invasive ECG Technique to Localize Culprit Vessel Occlusion Site in ST-Elevation Myocardial Infarction (STEMI) Patients

Background: Electrocardiograms (ECGs) are essential in identifying the type and location of acute myocardial infarction. In the setting of inferior wall myocardial infarction (IWMI), identification of the right coronary artery (RCA) as the culprit artery is important because of the potential complications associated with its involvement. Objectives: The study was conducted to identify the culprit artery responsible for STEMI from ECG tracings. To validate Fiol’s algorithm in Eastern Indian population and to compare the ECG findings with coronary angiogram. Methods: The cross-sectional study was conducted in 100 patients with acute STEMI. Patients presenting with acute ST-elevation myocardial infarction within 12 h of symptom onset were included in the study. In this study, we focused on Fiol’s algorithm and some other pre-specified criteria for prediction of occluded vessels. Cohen’s kappa statistical method was used to correlate ECG localisation of culprit artery with that of coronary angiogram. Results: Out of 100 STEMI patients, 73 patients had left anterior descending as the culprit artery, 24 patients had right coronary artery as the culprit artery and 3 patients had left circumflex artery as the culprit artery (73%, 24% and 3% respectively). Following Fiol’s algorithm, we have found that ECG has: high specificity (86%) but low sensitivity of 29% for an occlusion proximal to D1. Moderate sensitivity and moderate specificity (62% and 69% respectively) was noted for an occlusion distal to D1. Similarly, high sensitivity (90%) but low specificity (33%) was noted for lesion proximal to S1. Cohen’s kappa κ=1 suggests excellent agreement between ECG and coronary angiogram for inferior wall MI (both RCA and LCx occlusion). Conclusion: It can be concluded that ECG can reliably predict the culprit artery in STEMI patients. The Fiol’s algorithm is validated and considered as a simple tool to localize the infarct related artery in anterior wall myocardial infarction (AWMI) and inferior wall myocardial infarction (IWMI).