Abstract
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<0.01). The INR determined by the portable Coaguchek® XS tended to be high among the high INR group values (standard INR>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.
Figures and Tables
Fig. 1
The correlation between INRs by Coaguchek® XS and standard laboratory test (r=0.984, p<0.01). INR: international normalized ratio.
![kcj-39-71-g001](/upload/SynapseData/ArticleImage/0054kcj/kcj-39-71-g001.jpg)
References
1. Choi SY, Kim CH, Sohn DW, et al. Clinical characteristics and management in elderly patients with atrial fibrillation. J Korean Geriatr Soc. 1999. 3:82–90.
2. Choi SY, Kim CH, Kim YS, Hwang ES, Choi JO. Impacts of prophylactic measures on new thromboembolism in elderly patients with atrial fibrillation. J Korean Geriatr Soc. 2001. 5:129–138.
3. Choue CW. More aggressive drug therapy for the management of atrial fibrillation. Korean Circ J. 2002. 32:199–204.
4. Reynolds MW, Fahrbach K, Hauch O, et al. Warfarin anticoagulation and outcomes in patients with atrial fibrillation: a systematic review and metaanalysis. Chest. 2004. 126:1938–1945.
5. Gage BF, van Walraven C, Pearce L, et al. Selecting patients with atrial fibrillation for anticoagulation: stroke risk stratification in patients taking aspirin. Circulation. 2004. 110:2287–2292.
6. Kim YH. Rhythm control versus rate control of atrial fibrillation: pharmacologic and non-pharmacologic therapy. Korean Circ J. 2003. 33:553–558.
7. Gottlieb LK, Salem-Schatz S. Anticoagulation in atrial fibrillation: does efficacy in clinical trials translate into effectiveness in practice? Arch Intern Med. 1994. 154:1945–1953.
8. Bauman ME, Black KL, Massicotte MP, et al. Accuracy of the CoaguChek XS for point-of-care international normalized ratio (INR) measurement in children requiring warfarin. Thromb Haemost. 2008. 99:1097–1103.
9. Bereznicki LR, Jackson SL, Peterson GM, Jeffrey EC, Marsden KA, Jupe DM. Accuracy and clinical utility of the CoaguChek XS portable international normalised ratio monitor in a pilot study of warfarin home-monitoring. J Clin Pathol. 2007. 60:311–314.
10. Braun S, Watzke H, Hasenkam JM, et al. Performance evaluation of the new CoaguChek XS system compared with the established CoaguChek system by patients experienced in INR-self management. Thromb Haemost. 2007. 97:310–314.
11. Karon BS, McBane RD, Chaudhry R, Beyer LK, Santrach PJ. Accuracy of capillary whole blood international normalized ratio on the CoaguChek S, CoaguChek XS, and i-STAT 1 point-of-care analyzers. Am J Clin Pathol. 2008. 130:88–92.
12. Douketis JD, Lane A, Milne J, Ginsberg JS. Accuracy of a portable international normalization ratio monitor in outpatients receiving long-term oral anticoagulant therapy: comparison with a laboratory reference standard using clinically relevant criteria for agreement. Thromb Res. 1998. 92:11–17.