Assessment of validity of the ‘Culprit Score’ for predicting the culprit artery in patients with acute inferior wall myocardial infarction

Abstract

Background: Acute myocardial infarction is still a major health problem inspite of the impressive stride in diagnosis and treatment. Therefore, the early diagnosis and proper management is an important challenge. The identification of infarct related artery and site of occlusion in inferior wall myocardial infarction is extremely important to predict complications. Aim of the work: evaluating the use of ‘culprit score’ for prediction of the culprit artery in inferior wall MI Methods: This was a prospective observation study that was done from June 2017 to July 2018 and included 100 patients presented to the coronary care unit at Al-Azhar University Hospitals and National Heart Institute with inferior wall myocardial infarction. All patients were subjected to: history taking, clinical examination, ECG, cardiac enzymes, echocardiography and coronary angiography. Culprit Score is defined as: [(II -V2) / (III + V1 – aVL)] by measuring ST elevation in leads (II, III) and ST displacement in leads (V1, V2, AVL). Results:Mean age of patients involved in the study was 56.42+10.78 years with 80% of patients being male. The sensitivity and specificity, positive predictive value (PPV) and negative predictive value (NPV) of Culprit Score ≤ 0.5 to predict proximal RCA occlusions were 79.49 %, 86.89 %, 79.49 %, and 86.89 %, respectively and 0.5 to ≤ 1.5 to predict distal RCA occlusions were 78.13 %, 86.76 %, 73.53 %, and 89.39 %, respectively; and score >1.5 to predict LCX occlusions were 79.5 % and 86.9 %; 78.1 % and 86.7 %; and 75.8 % and 92.9 %, respectively. Conclusion: Culprit score could reliably predict the site of occlusion in inferior wall myocardial infarction.