A 75 year old woman who had been paced with a VVI system some years earlier underwent an elective incisional hernia repair and sigmoidoscopy. Her postoperative course was initially uncomplicated but on day 6 she developed spiking temperatures and rigors accompanied by paroxysms of hypoxia. Examination confirmed known mitral regurgitation. There were no signs of endocarditis. Chest radiography and ventilation/perfusion scan were unremarkable. Transthoracic echocardiography was un-changed from a previous study with normal A-V and semilunar valves, and mild mitral regurgitation. Blood cultures grewEnterobacter cloacae.

The triad of pyrexia, hypoxic paroxysms, and positive blood cultures strongly suggested right sided endocarditis, and transoesophageal echocardiography was performed. This revealed a 1.3 cm²highly mobile vegetation adherent to the eustachian valve. There was no evidence of endocarditis elsewhere. The patient responded well to intravenous antibiotics, with full resolution of the vegetation.

The eustachian valve is a remnant of the right sinus venosus valve, which is vestigial in the adult heart where it is highly variable morphologically, ranging from absence to a long thread-like, fenestrated structure or Chiari’s network. All five previously reported cases of eustachian valve endocarditis were secondary to staphylococcal infections: four cases related to intravenous drug use and one following staphylococcal pneumonia. This case is unusual asE cloacae is present in normal intestinal flora. There was no evidence that the pacing wire was either an infected site or source. However, intermittent contact between the eustachian valve and pacing wire may have resulted in endothelial damage, predisposing the valve to infection.

• Download figure
• Open in new tab
• Download powerpoint