CVM Cardiovascular Medicine 1664-204X 1664-2031 EMH Schweizerischer Ärzteverlag AG Farnsburgerstrasse 8 CH-4132 Muttenz 02190 10.4414/cvm.2022.02190 Original article Acute Coronary Syndromes Reliability of an ECG-algorithm for identification of the infarct-related artery in inferior myocardial infarction in clinical practice Buchmann Beate beate.buchmann@gmx.de Cardiology | Chur | SWITZERLAND | 0041 798951285 Rönz Tim Bonetti Piero O. Kantonsspital Graubünden 01 01 2022 25 01 0 0 Copyright: EMH Schweizerischer Ärzteverlag AG 2022 EMH Schweizerischer Ärzteverlag AG "Cardiovascular Medicine" is an open access publication of EMH published in accordance with the terms of the Creative Commons licence attribution - NonCommercial - NoDerivatives 4.0 International. You are free to share, copy and redistribute the material in any medium or format under the following terms: Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. NonCommercial — You may not use the material for commercial purposes. NoDerivatives — If you remix, transform, or build upon the material, you may not distribute the modified material. "Non-commercial" means not primarily intended for or directed towards commercial advantage or monetary compensation. The incorporation of publications in commercial products, the use of publications to advertise for commercial products or services and any other usage that directly or indirectly pursues commercial interests is subject to the express previous consent of the publishing house as part of a written agreement. Please send us your request in writing. Exact indication of the publication from which you would like to reproduce material and detailed information about its intended use help to facilitate and expedite request processing.

Background: The presence of ST-segment elevation in lead III exceeding that in lead II when combined with ST-segment depression in lead I, aVL or both, was proposed as a powerful predictor of occlusion of the right coronary artery with sensitivity/specificity values of 90%/71% in patients with acute inferior ST-segment elevation myocardial infarction (STEMI). The present study was performed to investigate the reliability of this ECG-algorithm in clinical practice. Methods: ECGs of all consecutive patients who presented to our hospital with acute inferior STEMI and underwent emergency coronary angiography/primary percutaneous coronary intervention between January 2006 and December 2013 were analyzed retrospectively by 2 independent cardiologists according to the criteria mentioned above. The results were then compared with the angiographic findings and 28-day mortality data were collected. Results: A total of 356 patients with acute inferior STEMI were included in the present study. The right coronary artery was the infarct-related artery in 272 (76.4%) patients and the left circumflex coronary artery in 76 (21.4%) patients, whereas inferior STEMI was caused by distal occlusion of a large left anterior descending coronary artery in 4 (1.1%)  and of the Ramus intermedius in 4 (1.1%) patients. In our population the sensitivity/specificity values of the proposed ECG-algorithm to correctly identify the right coronary artery were 78%/49%. There was a non-significant trend towards a higher 28-day mortality in patients with a positive ECG-algorithm (3.5% vs. 1.0% ; p=0.186). Conclusions: In the present study we could not reproduce the excellent diagnostic accuracy of an ECG-algorithm for predicting the infarct-related artery in acute inferior STEMI reported in the literature. Thus, given its suboptimal diagnostic reliability and the lack of therapeutic consequences in patients with acute inferior STEMI and a clear indication for immediate reperfusion therapy, the clinical relevance of the proposed ECG-algorithm is questionable.