An extremely low birthweight neonate, born at 23 weeks' gestation weighing 600 g, developed eustachian valve endocarditis as a complication of neonatal intensive care. In addition to the presence of intraumbilical lines and percutaneous long lines, there was also evidence of maternal chorioamnionitis. Current first-line therapies for presumed infection on this neonatal unit are amoxicillin and gentamicin usually given for up to 5 days. By the third week of life, following clinical deterioration, rising infection markers (C reactive protein and white cell count), a fall in platelets and three serial blood cultures positive for Staphylococcus haemolyticus, endocarditis was suspected. A diagnosis of endocarditis was confirmed on echocardiography to involve the eustachian valve (figure 1).

The eustachian valve is an embryological remnant found at the insertion of the inferior vena cava into the right atrium. It directs fetal blood towards the left atrium through the foramen ovale. It is infrequently visualised in adults …