A 71 year old man was admitted with fever and chills. On admission his temperature was 39°C; physical examination was normal except for a grade I/VI aortic systolic murmur. Blood cultures and urine samples grew Staphylococcus aureus. Transoesophageal echocardiography (TOE) showed a mildly calcified aortic valve without vegetations, and diffuse atheroma of the descending aorta. Despite appropriate antibiotic treatment the patient remained febrile, and developed clinical and radiological signs of pulmonary oedema. A subsequent TOE revealed the presence of two saccular aneurysms of the descending aorta, one just beneath the isthmus (panel A: AO, aorta), and the second one just above the diaphragm (panel B). These aneurysms arose from two localised ruptures in the atheromatous intima (arrows). The inferior one was responsible for a severe compression of the left atrium and right pulmonary veins, as shown by spectral and colour flow Doppler (panel C: LA, left atrium; LV, left ventricle; MA, mycotic aneurysm). Magnetic resonance imaging (spin echo T1 images) showed both mycotic aneurysms with a severely inflammatory shell and infiltration of the mediastinal fat, as well as the compressed left atrium (panel D: AA, ascending aorta; Pl.E, pleural effusion; RA, right atrium; RV, right ventricle; RPA, right pulmonary artery). The patient was considered too ill for surgery and died within a few days from multiorgan failure.