Shared Sheath Rupture, an Uncommon Presentation of Acute Aortic Syndrome: A Case Report and Literature Review.

Shared sheath rupture is a very rare form of acute aortic syndrome (AAS) that requires urgent diagnosis and management. We report the case of an 84-year-old gentleman who presented with acute chest pain, initially suspected to be ischaemic in origin. Elevated troponin supported a working diagnosis of acute coronary syndrome (ACS) and treatment was initiated; however, the patient subsequently deteriorated. Computed tomography angiography (CTA) was requested with suspicion of AAS. It revealed a penetrating aortic ulcer with haematoma extending into the shared adventitial space between the aorta and pulmonary trunk, the so-called 'shared sheath'. The patient was transferred for emergency surgical management. This case highlights a distinctly rare radiological finding, emphasising the importance of careful CTA interpretation, and illustrates the diagnostic challenges in differentiating AAS from ACS at presentation.