ABSTRACT

Electrocardiogram (ECG) is widely used in the diagnosis of myocardial infarction (MI). It mostly gives important hints to detect the infarct-related artery (IRA). The changes in the morphology and in the position of the heart cause changes in ECG as well. Though ECG is used for the diagnosis of MI, it is not sufficient on its own in detecting the location of the underlying lesion. The pathologies changing the morphology of the heart, such as the atrial septal defect (ASD), increase the margin of error of ECG. We report a rare case; falsely positive ECG for anteroseptal MI in patient with ASD admitted with acute coronary syndrome. Coronary angiography revealed right coronary artery (RCA) lesion in the patient with acute MI who was found to have ST elevation in both precordial and inferior derivations. As a potential cause of mismatch between IRA and infarct location at ECG, echocardiography showed right ventricle dilatation related with cribriform ASD. It was percutaneously closed at 30 days after MI. Therefore, when observed a mismatch between IRA and infarct location at ECG, a detailed ex- amination should be performed to determine potential causes of the mismatch.

Keywords: Myocardial infarction Atrial septal defect Electrocardiogram