Identification by means of an electrocardiogram of the guilty artery and of its level of occlusion in myocardial infarction with elevation of the ST segment

Background. In clinical practice, the identification of the culprit vessel and the localization of the occlusion site in ST-elevation myocardial infarction (STEMI) are provided by coronary angiography. Over the last few years, however, an increasing body of literature focused upon the reassessment of the ECG as a reliable technique to obtain this useful information. The aim of this study was to evaluate the accuracy of electrocardiographic criteria compared to coronary angiography. Methods. On the basis of the available literature, we developed an electrocardiographic algorithm based on the analysis of ST-segment elevation and reciprocal depression, whose accuracy was verified through its use in our cohort of 343 consecutive patients during calendar years 2008-2010. All patients underwent emergent percutaneous coronary intervention in the setting of acute STEMI. Patients with left bundle branch block, pacemaker rhythm and/or with a history of previous reperfusion were excluded. The admission electrocardiograms were reviewed by experienced cardiologists blinded to the angiographic findings. Results. The criteria adopted allowed a correct identification of the culprit vessel in 87.5% of cases. The sensitivity for left anterior descending, right coronary artery, left circumflex and diagonal branch/double anterior descending/ramus intermediate was 98.8%, 93.7%, 31.7% and 44.4%, respectively; the specificity was 94.3%, 87.6%, 99.0% and 99.1%, respectively. The proximal/distal location was correctly identified in 62.4% of cases. Conclusions. Our results confirm that careful interpretation of the ECG, which is a versatile and widely available tool, appears useful for the detection of the culprit vessel and the coronary occlusion site in STEMI patients, with relevant implications for clinical management and selection of appropriate therapeutic strategies.