Eustachian valve endocarditis: Case report and literature review.

In the intravenous drug user (IVDU) population, infected right-sided valvular lesions are common, and this has been well described in the literature. The Eustachian valve (also known as the valve of the inferior vena cava) is another valve in close proximity to the tricuspid valve, which can, in rare cases, be the focus of infection. Eustachian valve endocarditis may be an under-recognised complication of Staphylococcus bacteraemia in IVDU population, often only identified by transesophageal imaging. We present a case of tricuspid valve endocarditis in an IVDU with secondary seeding on the Eustachian valve, and an accompanying literature review on this rare topic.