Oral anticoagulant therapy achieved the lowest combined incidence of bleeding and thromboembolic complications at an international normalized ratio between 3.0 and 4.0 in patients after myocardial infarction.
RCT (n=3,404)
Double-blind
Randomized
Yes
What is the optimal intensity of oral anticoagulant therapy to minimize the combined risk of bleeding and thromboembolic complications in patients after myocardial infarction?
The optimal intensity of long-term oral anticoagulant therapy for post-myocardial infarction patients lies between an INR of 2.0 and 4.0 to balance hemorrhagic and thromboembolic risks.
Absolute Event Rate: 3.2% vs 8%
OBJECTIVES: This study attempted to determine the optimal intensity of anticoagulant therapy in patients after myocardial infarction. BACKGROUND: Treatment with oral anticoagulant therapy entails a delicate balance between over- (risk of bleeding) and under-anticoagulation (risk of thromboemboli). The optimal intensity required to prevent the occurrence of either event (bleeding or thromboembolic) is not known. METHODS: A method was used to determine the optimal intensity of anticoagulant therapy by calculating incidence rates for either event associated with a specific international normalized ratio. The numerator included events occurring at given international normalized ratios, and the denominator comprised the total observation time. RESULTS: The study population included 3,404 myocardial infarction patients enrolled in the ASPECT (Anticoagulants in the Secondary Prevention of Events in Coronary Thrombosis) trial. Total treatment was 6,918 patient-years. Major bleeding occurred in 57 patients (0.8/100 patient-years), and thromboembolic complications in 397 (5.7/100 patient-years). The incidence of the combined outcome (bleeding or thromboembolic complications) with international normalized ratio 5. After adjustment for achieved international normalized ratio levels, significant predictors were higher levels of systolic blood pressure and age. CONCLUSIONS: If equal weight is given to hemorrhagic and thromboembolic complications, these results suggest that the optimal intensity of long-term anticoagulant therapy for myocardial infarction patients lies between 2.0 and 4.0 international normalized ratio, with a trend to suggest an optimal intensity of 3.0 to 4.0.
Azar et al. (Wed,) conducted a rct in Myocardial infarction (n=3,404). Oral anticoagulant therapy vs. Placebo was evaluated on Combined outcome of bleeding or thromboembolic complications. Oral anticoagulant therapy achieved the lowest combined incidence of bleeding and thromboembolic complications at an international normalized ratio between 3.0 and 4.0 in patients after myocardial infarction.