For prosthetic heart valves the risk of infection is much higher than for native heart valves. During the course of infective endocarditis 20-40% of all patients suffer from cerebrovascular complications such as ischaemic stroke or intracerebral haemorrhage. We present the case of a 57-year-old woman who had undergone surgery to mechanically replace an aortic heart valve 11 months ago and suffered from repeated ischaemic strokes with secondary haemorrhage. The initial antibiotic regimen was ineffective in treating the later diagnosed Staphylococcus aureus infection of the prosthetic valve. Escalation of the antibiotic treatment was not able to halt the clinical course that finally led to the patient's death. The case report emphasizes the importance of early identification of the aetiology of infection in patients with mechanical heart valve replacement. Without rapid and adequate treatment there is a considerable risk for the development of severe neurological sequelae and cardiac failure that can ultimately result in a fatal course of this clinical picture.