Does adding antiplatelet therapy to oral anticoagulation reduce systemic embolism or death in patients with prosthetic heart valves?
Adding antiplatelet therapy to oral anticoagulation in high-risk prosthetic heart valve patients reduces systemic embolism and death at the cost of increased major bleeding.
Adding antiplatelet therapy, either dipyridamole or low-dose aspirin, to oral anticoagulation decreases the risk of systemic embolism or death among patients with prosthetic heart valves. The risk of major bleeding is increased with antiplatelet therapy. These results apply to patients with mechanical prosthetic valves or those with biological valves and indicators of high risk such as atrial fibrillation or prior thromboembolic events. The effectiveness and safety of low-dose aspirin (100 mg daily) appears to be similar to higher-dose aspirin and dipyridamole. In general, the quality of the included trials tended to be low, possibly reflecting the era when the majority of the trials were conducted (1970s and 1980s when trial methodology was less advanced).
Massel et al. (Tue,) studied this question.