A 14 year old girl was referred for management of Staphylococcus aureus endocarditis, severe mitral regurgitation, and congestive heart failure. She had received chemotherapy for left femoral osteosarcoma diagnosed four months earlier. Transthoracic echocardiography showed a large pericardial effusion and a 20 × 5 mm sausage shaped vegetation on the posterior mitral leaflet with severe mitral regurgitation (upper panels). Following pericardiocentesis, and antibiotic and diuretic treatment, the patient underwent mitral valve surgery. Intraoperative transoesophageal echocardiography showed a ruptured abscess cavity measuring 30 × 18 mm in the posterior mitral annulus, with regurgitation through the ring abscess (middle and lower panels). At surgery, there was severe panpericarditis and a large posteromedial mitral annular abscess, detaching P2 and P3 scallops from the annulus. The apparent vegetation was in fact the posterior mitral leaflet attached to the dehisced roof of the abscess cavity. The annulus was debrided and reconstructed using an equine pericardial patch and polypropylene sutures, and a 27 mm St Jude Medical mechanical prosthesis inserted. Transoesophageal echocardiography showed no further regurgitation and the patient is free of cardiac symptoms one year after surgery.

Transthoracic parasternal long axis echocardiograms. (A) Suspected infective vegetation (arrows) attached to a flail posterior mitral leaflet. Ao, aortic root; LA, left atrium; LV, left ventricle; RVO, right ventricular outflow. (B) Anteriorly directed colour jet of mitral regurgitation.

Transoesophageal long axis echocardiograms. (A) Loculated abscess in the posterior mitral annulus (arrowheads). The presumed vegetation consisted of the posterior valve leaflet (thick arrow) attached to the detached roof of the abscess (slender arrows). (B) Severe regurgitation from the left ventricular to left atrial fistula created by rupture of the abscess.

Transoesophageal echocardiograms, four chamber view. (A) Mitral annular abscess seen “en-face” (arrowheads). RA, right atrium; RV, right ventricle. (B) Turbulent systolic colour flow within the abscess cavity.