Randomised controlled trials, observational cohort studies, case series and case reports of patients with a mechanical heart valve and intracranial haemorrhage during anticoagulant therapy were eligible for inclusion. Re-starting of anticoagulant therapy and clinical follow-up had to be described. Studies in which intracranial bleeding occurred after valve replacement therapy were excluded.
In the included studies, patients' ages ranged from 60 to 69 years (mean) in observational cohort studies and from 11 to 70 years in the case reports. Mitral and/or aortic valve sites were included. The observational cohort studies reported subdural, intracerebral, subarachnoidideal and intraspinal haemorrhage sites; INR (International Normalised Ratio) varied (not reported in case reports). Outcomes reported were time of oral anticoagulant restarting, cerebral ischaemic and haemorrhagic events, and deaths. The time point at which antithrombotic therapy was restarted varied. The antithrombotic therapies used were warfarin, enoxaparin, nadroparin, heparin and dipyridamole where reported.
Two reviewers independently performed study selection and disagreements resolved by a third reviewer.