Infective Endocarditis in Patients with Mitral Annular Calcification: Clinical and Echocardiographic Presentation,...

Mitral annular calcification (MAC) poses unique challenges in infective endocarditis (IE). This study aimed to characterize echocardiographic features of IE involving MAC and assess its management and outcomes.

We reviewed cases discussed during our IE multidisciplinary meetings, 2021-2024. Clinical data, imaging findings, and outcomes were collected through chart review.

Among 741 patients evaluated, 51 patients (7%; aged 73 ± 11 years; 45% female) had possible or definite IE and moderate-severe MAC. IE involved the mitral valve in 24 patients (47%). Mitral IE was more frequent in women (63% vs 30%, P = 0.02) and was less commonly associated with prior aortic valve replacement (17% vs 59%, P < 0.01). Staphylococcus aureus was the most common pathogen, with no difference between groups (38% vs 30% in the mitral vs nonmitral IE groups, respectively, P = 0.55). Patients with mitral IE often presented with large vegetations (median 13 mm), frequent valvular or perivalvular complications (moderate or greater mitral regurgitation in 54%, perforation in 33%, and perivalvular abscess in 13%). A succulent aspect of the vegetation mass with abnormal MAC mobility, described as "rocking," was observed in 7 patients (29%). Surgical indications were found in 63% of patients, but only 40% underwent surgery due to high perceived risk. The in-hospital mortality incidence was not different between the mitral and nonmitral IE groups (29% vs 15%, P = 0.32).

In patients with IE and MAC, the mitral valve was often primarily affected, showing large, mobile vegetations with a "rocking" motion. Despite frequent surgical indications, few underwent surgery, highlighting the need for improved management in this high-risk group.