INTRODUCTION: Chiari networks are vestigial remnants of the right valve of the sinus venosus, present in 1.5 to 2.0% of the population. There have been rare case reports of complications including thrombus or infective endocarditis of a Chiari network. Masses on the Chiari network are extremely rare.
CASE PRESENTATION: A 41-year-old female, with a history of infective endocarditis a year ago, was admitted with low back pain, fever and chills for 3-4 days. She also had a history of recurrent urinary tract infections in the last two months. She was treated with Nafcillin for six weeks a year ago for infective endocarditis. She had a history of intravenous drug abuse in the remote past and also had a 20 pack year smoking history. Her blood cultures grew Methicillin-sensitive Staphylococcus Aureus. A transesophageal echocardiogram done to rule out infective endocarditis showed a 1.2 × 2.0 cm mass attached to the Chiari network in the right atrium. The patient was treated with antibiotics for 5 weeks and her fevers resolved and also her blood cultures turned negative. A repeat echocardiogram showed the continued presence of the mass with no change in dimensions. Due to recurrent episodes of infective endocarditis, the patient underwent surgery. The mass along with the Chiari network was removed. Histopathology of the mass was consistent with papillary fibroelastoma and the fibrinopurulent material on its surface consistent with infective endocarditis. Patient made uneventful post surgical recovery.
DISCUSSIONS: Papillary fibroelastoma resembles a sea anemone, consisting of multiple papillary-like fronds arranged on a stalk. These fronds have a collagen core surrounded by elastic fibers and loose connective tissue. Papillary fibroelastomas commonly occur on cardiac valves; they occur only rarely on the Chiari network. A case of infective endocarditis of a Chiari network per se has been reported once. However, this patient showed a rare site of papillary fibroelastoma on the Chiari network and infective endocarditis on the mass.
CONCLUSION: This patient underscores the fact that not all endocarditis occurs on heart valves. Rare tumors such as papillary fibroelastoma on a Chiari network can be a potential source of infective endocarditis.
DISCLOSURE: Faisal Latif, None.