Controlled Study of the Effective Level of Long-Term Anticoagulation

Christos B. Moschos, Tufts University School of Medicine
Peter C.Y. Wong, Tufts University School of Medicine
Herbert S. Sise, Tufts University School of Medicine

Document Type Article


In an attempt to determine the proper range of long-term anticoagulation, a group of patients under treatment were divided into three treatment groups, intensive, moderate, and control. While there was not a significant difference in the mortality in these 178 patients who were followed for two years, there was a statistically significant reduced number of thromboembolic complications both in the intensive and moderate treatment groups compared to the control group. Since there were more hemorrhages in the intensively treated group, the moderately treated patients fared the best overall. The Quick test results averaged 15 to 20 seconds; thrombotest, 8% to 20%; prothrombinproconvertin test, 20% to 50%; and factor II (prothrombin), 30% to 50%. These ranges are more moderate than the generally recommended ones. © 1964 American Medical Association. All rights reserved.