The bleeding risk may be accentuated by frequent concomitant usage of antiplatelet drugs. Russia has its own thromboplastins. These are derived from human brain tissue and have an ISI close to 1.0. Monitoring of oral anticoagulant control is performed by determination of the prothrombin index. Phenindione is the most frequently used oral anticoagulant agent.
Warfarin is unknown.
Russia would welcome assistance from the Subcommittee in this area. He recommended the method developed by colleagues in Leiden. He also indicated that this method could be adopted to define appropriate therapeutic ranges in different patient populations. Dr. van der Meer described the establishment of a new European group whose main activity would relate to clinical aspects of oral anticoagulant control. Those interested should contact Dr. van der Meer.