Right-sided infective endocarditis with coronary sinus vegetation

Background Infective endocarditis (IE) is a rare disease with high mortality. Right-sided IE accounts for 5–10% of cases of IE. The tricuspid valve is most commonly affected, oppositely in coronary sinus (CS). The diagnoses, treatments and outcomes of CS vegetation has not been summarized yet. Case presentation We present a 71-year-old man complained of cough and fever. Transthoracic echocardiography revealed the aneurysmal dilated CS with the band medium-echo mobile structure. A sinus venosus atrial septal defect has been detected. He had a persistent left superior vena cava which drained the right atrium via the aneurysmal dilated CS. Blood cultures were positive for Staphylococcus aureus . After intravenous antibiotic therapy, he had the symptom of dyspnea. The suspicious diagnosis is recurrent septic lung emboli which was confirmed by thoracic contrast enhanced computed tomography. The thoracotomy was performed to repair the atrial septum and remove the CS vegetation. Ten days later, the patient was discharged with only mild cough. Conclusion Both positive blood cultures and echocardiography are major criteria in right-sided IE with CS vegetation. Current treatment options of CS vegetation include medical therapy and surgery. The surgical strategy for CS vegetation should be individualized, due to the controversial indications and optimum time of surgery. Most people have a good prognosis after proper treatment.