E2252. Mycotic Aneurysms and Infective Endocarditis: Spectrum of Disease and Imaging Findings
  1. Zhuyi Rebekah Lee; Singapore General Hospital
  2. Chu Ming Mindy Choong; Singapore General Hospital
Mycotic (infected) aneurysms are an uncommon but potentially deadly condition in which the vascular wall is weakened by infection, leading to aneurysmal dilatation of the artery. These can occur anywhere in the body, but preferentially involve the major vessels such as the aorta and intracranial arteries, which can have devastating consequences of rupture or embolization. A leading risk factor for these aneurysms is infective endocarditis, which is usually diagnosed by the cardiology colleagues via transthoracic or transesophageal cardiac echography. We describe the echo imaging findings and CT correlations. We describe a case series of various mycotic aneurysms and infective endocarditis and the attendant clinical presentations, serial follow-up, management, and eventual outcome.

Educational Goals / Teaching Points
Illustrate the imaging findings spectrum of mycotic aneurysms and infective endocarditison CT angiography and correlation with cardiac echography, associated non-vascular findings that may be present on CT angiography, and the management options, with particular attention to endovascular treatment by interventional radiology.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
CT angiography is the modality of choice due to its speed and spatial resolution. It is highly sensitive and specific. CT findings of a lobulated dilatation of arteries, with inflammatory changes of perivascular stranding and soft tissue thickening, mural thickening, or perianeurysmal gas are diagnostic for mycotic aneurysm. Complications such as free rupture, hematoma, and end organ infarcts are also demonstrated easily on CT. Infective endocarditis is often diagnosed on cardiac echography performed by our cardiology colleagues. However, with ECG gated CT, we can demonstrate vegetations and paravalvular abscesses that correlated to cardiac echography findings. Associated non-vascular findings include those of spondylodiscitis and cavitating lung abscesses. Management of each mycotic aneurysm differs greatly depending on case. Intimate discussion between the surgeons (vascular, cardiothoracic, and/or neurosurgical) and interventional radiologistry as well as the infectious disease/medical team is paramount. Management options include a combination of aggressive surgical debridement, endovascular stent repair, endovascular embolectomy, and long-term antimicrobial medical therapy.

By demonstrating the natural progression of mycotic aneurysms and infective endocarditis, we hope to highlight the importance of timely imaging for diagnosis and management. We hope this primer for residents will assist them in recognizing the clinical urgency of mycotic aneurysm and making faster and more confident diagnoses.