Silent brain infarctions in patients with rheumatic mitral stenosis

Silent brain infarctions (SBI) are commonly detected in brain imaging. The association of SBI with rheumatic mitral stenosis (MS) is not clearly relevant. Based on magnetic resonance imaging, we aimed to describe the prevalence of SBI in patients with rheumatic MS and the cardiac abnormalities related to their occurrence.

This was a bicentric, cross-sectional study, conducted in Fez, Morocco which enrolled neurologically asymptomatic patients with rheumatic MS. The presence of SBI was scored on brain MRI. Age, sex, cardiac rhythm and oral anticoagulation (OAC) statement were recorded. We obtained mitral valve area and left atrium (LA) size through transthoracic echocardiography. Univariate and multivariate analysis were used to assess associations between presence of SBI and the explanatory variables.

Among the 100 patients with MS (mean age 47.08 ± 9.89 years, 72 % female, sex ratio: 0.38), 56 patients had SBI (56 %), including 7 with lacunar pattern. Patients with SBI were significantly older, had more frequently moderate/severe MS, and poorer control of INR when under OAC. Enlarged LA was strongly associated with SBI, either in patients with atrial fibrillation (AF) or in patients with sinus rhythm. Multivariate analysis revealed that enlarged LA (OR 20.15, [95 % CI 2.35-172.33]; p = 0.006) and labile INR (OR 3.86, [95 % CI 1.36-10.98]; p = 0.01) were independent predictors of SBI in patients with MS.

Patients with MS are at high risk of SBI. This risk increases with age, the severity of MS and above all the dilatation of LA, even without AF.