Background In controlled clinical trials with patients with cardiovascular disease, both antiplatelet and oral anticoagulant therapy have proved effective in reducing thrombotic and thromboembolic complications. The combination of both therapeutic strategies has been evaluated in several cardiovascular conditions.
Methods A meta-analysis was performed on the bleeding risk in six published trials of combined oral anticoagulant and antiplatelet therapy.
Results The results of clinical trials (in patients with artificial heart valves and in patients with unstable angina or non-Q myocardial infarction) suggest that combined oral anticoagulant and antiplatelet therapy may be as safe as oral anticoagulation alone. Also, in a large study of healthy subjects the safety of combined oral anticoagulant and low-dose antiplatelet therapy was acceptable at one to two major bleedings per 100 person-years more than with oral anticoagulation alone.
Conclusions The safety of combined oral anticoagulant and antiplatelet therapy is probably acceptable, provided the antiplatelet therapy is given in a low dose. These results warrant an efficacy and safety evaluation of combined oral anticoagulant and low-dose antiplatelet therapy in large clinical trials.
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