Impact of routine brain imaging on the prognosis of patients with left-sided valve infective endocarditis without neurological manifestations

Background: There are limited data on the impact of routine use of brain magnetic resonance imaging (MRI) on the prognosis of neurologically asymptomatic patients with left-sided infective endocarditis (IE). Methods: Among patients diagnosed with possible or definite IE in two tertiary referral centers between January 2005 and March 2019, we identified 527 left-sided IE patients without neurological symptoms or signs at the time of diagnosis. Patients who underwent brain MRI within 1 week after the IE diagnosis were classified as the routine brain imaging group (n = 216), and the rest were categorized as the control group (n = 311). All-cause mortality at 3 months, attributable mortality (defined as death directly related to IE), and fatal neurological events compared after adjustment using inverse probability of treatment weighting (IPTW). Results: During a median follow-up of 57 months, the routine brain imaging group had a similar risk of 3-month all-cause mortality to the control group in the multivariate analysis (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.24–1.14) and IPTW-adjusted cohort (HR, 0.59; 95% CI, 0.25–1.42). The risks of attributable mortality and fatal neurological events were also similar between the two groups in the multivariable analysis and IPTW-adjusted cohort. In the subgroup analysis, the routine brain imaging group showed more favorable outcomes in cases of large vegetation (> 10 mm) or acute-onset microorganisms. Conclusions: Routine use of brain MRI in left-sided IE patients without neurological manifestations is not associated with improved clinical outcomes. However, routine brain imaging in appropriate clinical settings could improve clinical outcomes.