MINOCA Presenting as Anterior STEMI in a 19-year-old Complicated by Complete Heart Block and Pacemaker Implantation: A Rare Case Report

Background Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) accounts for 5–10% of all cases of acute myocardial infarctions. It has recently been observed in increasing numbers in younger patients without established coronary risk factors. While thought to be less severe, MINOCA may be associated with malignant arrhythmias and conduction disturbances. A post-anterior ST-elevation myocardial infarction (STEMI) complete heart block (CHB) is uncommon in this demographic and may be related to severe septal ischemia. Case Presentation We describe a case of a 19-year-old male who never had comorbid conditions before admission for classic ischemic chest pain with anterior STEMI. He underwent streptokinase thrombolytic therapy, for which coronary arteriography disclosed normal coronaries with suggestions of transient thrombotic occlusions with spontaneous recanalization. He returned with recurrent pain in the chest with prompt development of symptomatic CHB with hypotension for which he required dopamine infusion with transvenous pacing. His conduction disturbances progressed from CHB to bifascicular block, then to trifascicular block, with CHB eventually. Repeat coronary arteriography disclosed normal coronaries once more. The echocardiogram disclosed an ejection fraction of 45% with moderate wall motion abnormalities. Because of conduction instabilities, he underwent permanent pacing with significant improvement thereafter, to be sent home in stable conditions. Conclusion This case brings into focus a very rare presentation of MINOCA in a young patient that was complicated by progressing conduction system disease that needed permanent pacing. The importance of early recognition of MINOCA-related STEMI due to conduction system disease with careful monitoring, irrespective of a normal coronary cath angiogram, can once again be appreciated.