Valve replacement in patients with endocarditis and cerebral septic emboli. Cerebral septic emboli complicate the cases in 20% to 40% of patients with left-sided endocarditis but the management of these patients who require a valvar operation remains unclear. From 1980 to 1988, the incidence of cerebral septic embolus was 42% (n = 45) among 106 patients with endocarditis who underwent valve replacement at the University of Illinois Hospital in Chicago. Of these 45 patients, 69% (n = 31) had symptomatic cerebral septic infarctions and 31% (n = 14) were asymptomatic. Findings on cerebral computed tomographic scans included ischemic infarcts (n = 36, 80%), hemorrhagic infarcts (n = 5, 11%), normal studies (n = 2, 4%), and unknown (n = 2, 4%). Neurological complications after valve replacement included postoperative strokes (n = 6, 6%), cerebral abscesses (n = 2, 2%), and seizure (n = 1, 1%). The presence of a hemorrhagic infarct preoperatively predisposed to a perioperative stroke (p less than 0.05). In conclusion, cerebral septic infarctions, both symptomatic and asymptomatic, are common among patients with endocarditis referred for valvar operation. In the absence of a hemorrhagic infarct, valve replacement can be performed with minimal risk of a perioperative stroke. 