Case report
A 61-year-old man was admitted to hospital for chills, myalgia and anorexia evolving for two weeks. His past medical history was notable for hypertension, hypercholesterolemia, and tobacco abuse. Laboratory tests on admission showed an elevated C-reactive protein at 161 mg/dl, a hyperleukocytosis at 17 000/mm3, elevated total and direct bilirubin levels and liver enzyme alteration. Thoraco-abdominal CT-scan revealed the presence of multiple bilateral pulmonary consolidations compatible with lung abscess. Repeat blood cultures were positive for a methicillin-sensitive Staphylococcus aureus (MSSA). Transesophageal echocardiogram (TEE) (Figure 1) showed the presence of a huge right ventricular mass attached to the anterior leaflet of the tricuspid valve associated with a moderate tricuspid regurgitation.
The most likely diagnosis was an infective tricuspid valve endocarditis caused by MSSA, with a large vegetation and complicated by pulmonary abscess. Intravenous antibiotic therapy with cefazoline (preferred to flucloxacillin in the context of impaired liver enzymes) was initiated and the patient was scheduled for an urgent surgery due to the risk of massive pulmonary embolism.
Surgery under median sternotomy was preferred to a minimally invasive approach due to the embolic risk associated with the Seldinger technique required for peripheral venous cannulation. At the opening of the right atrium, we discovered a giant lobulated mass attached to the anterior leaflet of the tricuspid valve by a broad pedicle, near the antero-septal commissure (Figure 2). The mass was removed, excising part of the anterior leaflet (Figure 3). The defect was repaired by a bovine pericardial patch and two artificial neochordae were passed to the free margin of the pericardial patch and attached to the anterior papillary muscle. The antero-septal commissure was closed by an edge-to-edge stich and an annuloplasty using a 34 mm Carpentier-Edwards Physio Tricuspid ring was performed.
Postoperative echocardiography demonstrated a good functional result on the tricuspid valve, with trace residual tricuspid regurgitation without stenosis (mean transvalvular gradient of 1.8 mmHg). The resected mass was composed of fibrin deposition on microscopic examination, consistent with an infectious vegetation. Culture of the vegetation revealed the presence of MSSA and intravenous cefazoline was continued for 42 days after surgery. The postoperative course was uneventful. The 3-month follow-up assessment was satisfactory, showing an excellent tricuspid valve function without signs of infection recurrence.