Unusual ST-t changes in Ebstein's anomaly with occlusion of a nondominant coronary artery

We present a case report of a patient of Ebstein's anomaly presenting with unusual ECG changes during acute coronary syndrome. The patient had undergone radiofrequency ablation of right posteroseptal accessory pathway. Two years later, he presented with acute chest pain. His ECG revealed ST elevation of 6-7 mm in leads III, aVF. V3R and V1-V4 with atrioventricular dissociation. He was thrombolysed for the same. He subsequently underwent an angiogram for continuing angina. His angiogram showed a nondominant right coronary artery with a 95% stenosis. The left circumflex artery was dominant but without any stenosis. The left anterior descending artery was also normal. Angiogplasty and stenting were done for the right coronary artery lesion and the patient did well on follow-up. The ST segment elevation in the anterior precordial leads resulting from occlusion of a nondominant right coronary artery is unusual. The possible reason for this is the isolated right ventricular infarction in the absence of any left ventricular infarction. Thus the electrical current of injury resulting from the right ventricular infarction was unopposed by any counterbalancing current of injury from the inferior surface of the left ventricle.