Clinical Utility and Accuracy of Coaguchek® XS, a Reliable Alternative to Laboratory International Normalized Ratio Monitoring in Korean Patients With Atrial Fibrillation

Background and Objectives: To evaluate the accuracy and the clinical utility of the Coaguchek ® XS, a portable point-of-care coagulometer, compared to standard laboratory methods in Korean patients. Subjects and Methods: We included 107 patients with atrial fibrillation on long-term oral warfarin therapy. The prothrombin time as expressed by the international normalized ratio (INR) was measured by the portable Coaguchek ® XS system as well as standard laboratory methods. Agreement between the two methods was defined as a difference of less than 0.3 between the INR values. Results: The INR determined by the portable Coaguchek ® XS had excellent correlation with the values obtained by standard methods (r=0.984, p 3.0). There was a 91.6% agreement between the two methods. Only nine cases (8.4%) had a difference of more than 0.3; this was mainly noted in the high INR group. Conclusion: The portable self-testing of the INR by the Coaguchek ® XS might be a reliable