A Very Rare Case of Primary Mural Endocarditis of the Right Atrium due to Candida Albicans

Abstract

Right-sided infective endocarditis accounts for 5-10% of all infective endocarditis cases. Fungal endocarditis represents 1-3% of all of infective endocarditis cases, with Candida spp. being the most common microbiological cause. Primary mural endocarditis is defined by the absence of valvular vegetations together with the presence of vegetations on the endocardial free wall that are not associated with myocardial abscesses, cardiac structural abnormalities, devices, prosthetic material, thrombi or tumors. It constitutes a very rare entity and only 63 cases have been published the literature. C. albicans is the microbiological cause in only nine of these cases, none of which involves the right atrium. We report the case of a frail 84-year-old female patient with a pacemaker presenting with fever. In the transthoracic and three-dimensional transesophageal echocardiograms, a mobile mass was found attached on the free wall of the right atrial base. Blood cultures were positive for C. albicans and the modified Duke criteria were fulfilled for a definite diagnosis of infective endocarditis. After evaluation from a heart team the patient was managed with transvenous lead extraction and intravenous high-dose caspofungin, according to the 2023 Guidelines of the European Society of Cardiology for the management of endocarditis. Pacemaker lead cultures were negative leading to the diagnosis of primary mural endocarditis. The patient responded well to treatment with significant clinical and laboratory improvement. Long-term oral fluconazole was initiated after hospital discharge with a close follow-up plan. To our knowledge this is the first case of primary mural endocarditis of the right atrium due to C. albicans.