RESUMEN
<p><b>OBJECTIVE</b>To investigate the proper anticoagulation intensity in patients after mechanical heart valve replacement in china.</p><p><b>METHODS</b>The anticoagulation therapy intensity and the complications in 480 patients after mechanical heart valve replacement were studied.</p><p><b>RESULTS</b>The follow-up rate was 89.17%, the total patient-years (Pty) was 2,110.04 years, the mean oral import warfarin dosage was (2.81 +/- 0.95) mg/day, and native warfarin dosage (2.38 +/- 0.46) mg/day. The mean PTR value of 2 116 samples was 1.43 +/- 0.26, and the INR value of 1 195 samples was 1.63 +/- 0.49. The total hemorrhage rate was 4.60% Pty, and the hemorrhage death rate was 0.38% Pty. The PTR and INR values were higher in the hemorrhage group than in the no-hemorrhage group. (t = 1.816, P < 0.05; t = 2.407, P < 0.01). The thromboembolism rate was 0.66% Pty, and the thromboembolism death rate was 0.05% Pty. There were 15 pregnancies in 14 women patients and no malformed newborns were found.</p><p><b>CONCLUSIONS</b>The most important complication of anticoagulation therapy after mechanical heart valve replacement is hemorrhage in china; The proper anticoagulation intensities of this group are INR 1.5-2.0 and PTR 1.3-1.5. It is beneficial to adopt the low intensity anticoagulation therapy for decreasing the death rate from hemorrhage, protecting pregnant women and newborns from hemorrhage and malformation, and improving the life qualities of the patients.</p>