An unusual case of infective endocarditis: extension of a tricuspid valve vegetation into the left atrium through a patent foramen ovale.

Tricuspid valve endocarditis frequently occurs in the setting of intravenous drug use. A case of tricuspid valve endocarditis in a 37-year-old woman with a history of intravenous cocaine use is described. Transthoracic echocardiography showed extension of the tricuspid valve mass through a patent foramen ovale and into the left atrium. One week after intravenous antibiotic treatment, the mass no longer traversed the patent foramen ovale, and only two smaller tricuspid valve vegetations remained. The present case demonstrates the value of performing a complete and thorough transthoracic echocardiography to visualize and evaluate both the right- and left-sided consequences of infective endocarditis in intravenous drug users. It also serves as a useful reminder to physicians caring for such patients that right sided endocarditis can have important left-sided complications.