Comparison of the Performance of the Warfarin Pharmacogenetics Algorithms in Patients with Surgery of Heart Valve Replacement and Heart Valvuloplasty

• The algorithms had similar performance during the initial and stable phase of anticoagulation treatment.
• The Gage et al. algorithm had better performance in both phases of initial and stable anticoagulation treatment.
• Progressive decrease in sensitivity to warfarin has been discovered in patients of our study.
• Most algorithms were more accurate in the ideal dose group.
• It is more accurate to select algorithms with the derivation population of mixed races or same race for clinical application.

A large number of warfarin pharmacogenetics algorithms have been published. Our research was aimed to evaluate the performance of the selected pharmacogenetic algorithms in patients with surgery of heart valve replacement and heart valvuloplasty during the phase of initial and stable anticoagulation treatment.10 pharmacogenetic algorithms were selected by searching PubMed. We compared the performance of the selected algorithms in a cohort of 193 patients during the phase of initial and stable anticoagulation therapy. Predicted dose was compared to therapeutic dose by using a predicted dose percentage that falls within 20% threshold of the actual dose (percentage within 20%) and mean absolute error (MAE).The average warfarin dose for patients was 3.05 ± 1.23 mg/day for initial treatment and 3.45 ± 1.18 mg/day for stable treatment. The percentages of the predicted dose within 20% of the therapeutic dose were 44.0 ± 8.8% and 44.6 ± 9.7% for the initial and stable phases, respectively. The MAEs of the selected algorithms were 0.85 ± 0.18 mg/day and 0.93 ± 0.19 mg/day, respectively. All algorithms had better performance in the ideal group than in the low dose and high dose groups. The only exception is the Wadelius et al. algorithm, which had better performance in the high dose group.The algorithms had similar performance except for the Wadelius et al. and Miao et al. algorithms, which had poor accuracy in our study cohort. The Gage et al. algorithm had better performance in both phases of initial and stable treatment. Algorithms had relatively higher accuracy in the > 50 years group of patients on the stable phase.