Immunoglobulin G4-related coronary artery pseudo aneurysm presenting as non-ST-segment elevation myocardial...

Immunoglobulin G4-related disease (IgG4-RD) is a rare, multifocal fibro-inflammatory disorder that can affect various organs, including the coronary arteries. Coronary artery pseudoaneurysm is an exceptionally uncommon manifestation of IgG4-RD, with only a few cases documented in the literature. We present a case of a 51-year-old gentleman who reported chest pain and was diagnosed with non-ST-segment elevation myocardial infarction (NSTEMI). Coronary angiography revealed a pseudoaneurysm of the left anterior descending artery (LAD) along with significant stenosis prior to it and extensive coronary artery ectasia. Further imaging and histopathological evaluation confirmed IgG4-RD. Surgical intervention with off-pump coronary artery bypass grafting using left internal mammary artery (LIMA) to mid left anterior descending artery (LAD) and pseudoaneurysm ligation was performed successfully. Postoperative outcomes were favorable, with the patient being discharged on corticosteroid therapy for IgG4-RD management. This case highlights the diagnostic and therapeutic challenges of coronary artery pseudoaneurysm in the context of IgG4-RD. Early recognition of IgG4-RD as an underlying cause of coronary artery pseudoaneurysm is critical. Multidisciplinary approach is essential to achieve favorable clinical outcomes.