CONGRESS ABSTRACT

Background: Infective endocarditis results from a complex interplay among bacterial virulence factors, coagulation, and hemodynamics.Native pulmonary valve endocarditis is a very rare phenomenon. Similarly, the development of a thrombus on the pulmonary valve is uncommon. In the following clinical case, these two rare events appear interconnected.
Clinical Case: A 66-year-old male presented to the emergency department with a history of weight loss, asthenia, and fever lasting two months, partially relieved by empirical antibiotic therapy. Initial diagnostic tests revealed sinus tachycardia and a slight increase in inflammation markers. A chest radiograph showed pulmonary consolidation, leading to further investigation with a CT pulmonary angiogram. This identified a large mass at the pulmonary valve, with a suspicion of thrombosis, accompanied by right segmental pulmonary embolism and associated pulmonary infarction. A transthoracic echocardiogram confirmed the presence of two iso-anechoic masses adherent to the pulmonary valve, predominantly on the anterior and left cusps, as seen in 3D reconstruction. Dysfunction or dilation of the right ventricle, as well as vegetations on the other valves, were ruled out. The patient was urgently admitted to the cardiac intensive care unit. Empirical antibiotic therapy was initiated due to suspected endocarditis, and blood
cultures were performed, which resulted negative. Despite being classified as intermediate-low risk for pulmonary embolism severity, considering the imminent risk of embolization from the identified mass, cardiothoracic surgery was performed. The procedure involved replacing the pulmonary valve with a bioprosthesis and removing the two neoformations. Pathological analysis indicated endocarditis of the pulmonary valve with transmural ulcerative inflammation and a thrombotic nature of the two masses. The culture of the valve was negative, suggesting a possible resolution of the infectious process. The postoperative period was stable, and the patient was subsequently enrolled in a cardiac rehabilitation program, with indications to continue anticoagulant therapy until reevaluation and antibiotic therapy with ceftriaxone and vancomycin for up to six weeks post-surgery. As far as we know, this is the first time in the literature that thrombus formation on a native pulmonary valve following endocarditis has been documented.