INCREASE IN ACCEPTANCE OF THE INTERNATIONAL NORMALIZED RATIO (INR) FOR THE MANAGEMENT OF ORAL ANTICOAGULANT-THERAPY

In 1994 the German Cardiac Society recommended the International Norma lized Ratio (INR) instead of ''Quick's test'' for the longterm managem ent of oral anticoagulation therapy. Parallel cardiac surgical centers in Germany and Switzerland started patient recruitment for the GELIA study (German Experience with Low Intensity Anticoagulation). By the e nd of 1996, 862 consecutive patients with mechanical heart valve repla cement had been enrolled. According to the protocol of the GELIA study , intensity of anticoagulation, methods used to control the oral antic oagulation therapy as well as other factors relevant for the anticoagu lation management are reported every three months. The so far accumula ted data material of the GELIA study seemed, therefore, appropiate to analyze potential changes in the acceptance of INR during the time per iod 1993-1996. Potential differences in the anticoagulation management were analyzed separately according to the time of enrollment of patie nts and changes during the follow up period, e. g., a switch from ''Qu ick's test'' to INR. Taking the time of enrollment into account, the p ercentage of patients who had INR-controlled oral anticoagulation ther apy increased from 0 % (1993), 14.3 % (1994), 63.2 % (1995) to 74.2 % in 1996. During the follow up, there was a change from ''Quick's test' ' to INR controls in 7 patients (1994; 2.1 %), 67 patients (1995; 10.5 %) and 142 patients (1996; 17.3 %) with a consequent increase of INR controlled patients to a total of 34.2 % in 1994, 52.0 % in 1995, and 73.9 % in 1996.