Abstract

We report a rare case of Staphylococcus lugdunensis (S. lugdunensis) endocarditis in a 42-year-old male with a bicuspid aortic valve and an ascending aortic aneurysm. The patient initially presented with upper respiratory symptoms but rapidly deteriorated, developing acute pulmonary edema. Transthoracic and transesophageal echocardiography demonstrated severe aortic regurgitation, vegetation on the bicuspid valve, and a 52-mm ascending aortic aneurysm. Intraoperative assessment revealed extensive destruction involving the mitral–aortic intervalvular fibrosa (MAIVF), membranous septum, and anterior mitral leaflet. Emergency surgery was performed, including reconstruction of the MAIVF and membranous septum, mechanical aortic valve replacement, and ascending aortic replacement via the Wheat procedure. Tissue and blood cultures grew S. lugdunensis, which was sensitive to vancomycin. The patient completed a six-week antibiotic regimen and was discharged in stable condition.
This case highlights a unique association between S. lugdunensis endocarditis and focal MAIVF destruction in bicuspid aortic valve disease, underscoring the importance of timely surgical intervention.

Key words: Staphylococcus lugdunensis, mitral–aortic intervalvular fibrosa, wheat procedure, infective endocarditis, reconstructive cardiac surgery