Oral anticoagulant in patients surviving myocardial infarction. A new approach to old data.

Evidence of the preventive efficiency of long term oral anticoagulant (OA) therapy after myocardial infarction (MI) is still controversial. In an attempt to reappraise this problem, a study has been undertaken using the odds ratio method in which the data from 7 published studies of long term OA therapy after MI were pooled. The studies selected met predefined quality standards. The combination of the studies provided a sample of 1284 patients in the OA group versus 1013 in the reference group. The total mortality rates were 20.73% in the control group and 17.99% in the OA group; the difference is significant at p = 0.05. For recurrent MI only 5 trials could be pooled. The reinfarction rates were 13.81% in the control group versus 10.25% in the OA group, and again the difference is significant. The interpretation of such reassessed data is subject to certain limitations.