Mycotic Aortocoronary Saphenous Vein Graft Aneurysm Presenting With Unstable Angina Pectoris

Rapidly expanding saphenous vein graft myoctic aneurysm causing ST-elevation myocardial infarction: a case report

Background 

Mycotic aneurysms of coronary vein grafts are rare and associated with high mortality. They are most commonly a result of surgical or percutaneous intervention, and present with complications including myocardial infarction (MI), infective endocarditis. A recent literature review identified 97 cases of mycotic coronary aneurysms in total.

Case summary

A 49-year-old man with a history of coronary artery bypass grafting and septic arthrithis presented with chest pain and fevers and ST elevation on electrocardiogram. Urgent angiogram showed an aneurysmal saphenous vein graft from the PL branch to PDA-no acute intervention was performed due to concern about bacteraemia. Methicillin-sensitive Staphylococcus aureus was grown in urine and blood but no focus of infection was identified. Despite treatment with antibiotics and antiplatelets, the patient returned with evidence of expansion of the SVG aneurysm requiring surgical resection.

Discussion 

This case highlights the difficulty in treating acute coronary syndromes involving mycotic aneurysms. Multimodal imaging approaches are useful to identify suspected infection, but false negatives occur. Due to high risk of rupture or haemorrhage, there are limited options for urgent reperfusion in cases of MI with mycotic aneurysm, demonstrating the need for an individualized approach and close follow-up.

Outcome of a giant coronary artery mycotic pseudoaneurysm secondary to non-typhoid Salmonella managed without surgical intervention

A 48-year-old woman with a history of AIDS, a recent coronary artery bypass graft operation and prior bacteraemia with non-typhoid Salmonella presented with non-exertional chest pain and elevated troponins. The cardiac catheterisation and coronary CT angiography revealed a 9 cm pseudoaneurysm arising from the proximal left anterior descending artery. The blood cultures confirmed non-typhoid Salmonella. Emergent surgery was initially deferred due to her complex anatomy. Moreover, the hospital course was complicated by Epstein-Barr virus meningitis and an associated decline in the patient’s mentation. Consequently, the mycotic pseudoaneurysm was medically managed with antibiotics and strict blood pressure goals. The natural history of giant mycotic coronary artery pseudoaneurysm formation and progression is appreciated through this first reported medically managed case. The follow-up coronary CT angiography at 3 months showed evidence of pseudoaneurysm leakage into surrounding tissue. The patient expired at 5 months from an unknown cause.