Low standard oral anticoagulation therapy for Chinese patients with St.Jude mechanical heart valves

Objective To study the efficacy of the low standard oral anticoagulation therapy following St Jude Medical (SJM) valve implantation for Chinese patients.Methods Totally 805 patients with a mean age of 42.70±11.09 years,enrolled into this study. Among them,230 underwent aortic valve replacements (AVR),381 mitral valve replacements (MVR),189 double valve replacements (DVR) and 5 tricuspid valve replacememts (TVR). All patients received postoperative oral anticoagulation therapy based on a low standard of international normalized ratio (INR,2.0-2.5). Of the 805 patients,710 were followed up for 0.25-13 years (a median,4.15 years). Results Postoperatively,17 adverse events occurred. Operative mortality was 2.11%. The most frequent cause of operative mortality was a low cardiac output. During follow-up,there were 47 anticoagulant-induced hemorrhages [1.59%/patient-year (pt-yr)],10 cases of thromboembolism (0.34%/pt-yr),and 3 mechanical valve thromboses (0.19%/pt-yr). There were 44 late deaths and the linearized late mortality rates were 0.51%pt-yr. Estimates of actuarial survival for all patients at 5 and 10 years was 97.45% (0.70%) and 77.96% (17.44%),respectively.Conclusions A low target INR range of 2.0-2.5 is preferable for Chinese patients so as to reduce the severe bleeding complications in those with conventionally higher levels of INR. The long-term results were satisfactory in terms of the numbers of those who suffered thrombosis,embolism and bleeding.