Background: Non-bacterial thrombotic endocarditis (NBTE), also known as marantic endocarditis or Libman-Sacks endocarditis, is a rare non-infectious condition affecting mostly the left-sided heart valves of patients who, most often, suffer from malignancies and connective tissue disorders. Herein, we present a case of a male patient with marantic endocarditis due to occult lung adenocarcinoma.
Case Presentation: The patient fulfilled the modified Duke's criteria of possible bacterial endocarditis of the aortic valve; however, multiple blood cultures and serological tests were negative.