| Objectives: To evaluate some methods to monitor anticoagulation therapy of warfarin.Methods: 1,Cases of prosthetic heart valve replacement were collected from June 2005 to May 2006 in the 2nd Affiliated Hospital of Nanchang University, general informations were also recorded.2,48 hours after prosthetic heart valve replacement, patients took warfarin, about 6.0mg or 5.0mg on the first day, 3.0mg or 2.5mg on the next day. All of them were tested international normalized ratio (INR) and prothrombin time (PT). We defined the therapeutic INR range as 1.8 to 2.5 for examination of outcomes. All patients were adjusted the dosage of warfarin according to INR value.3,Follow-up visit started when patients took warfarin, ended on 31st of December 2006. Complications, INR values (including INR values measured in the other hospitals) and warfarin dosage by out-patient review and telephone calling were recorded.4,18 out-patient cases from our hospital were adopted HPLC to measure plasma concentrations of warfarin during September 2006.5,Analyse follow-up results, relationship between INR value and plasma concentrations of warfarin, and relationship between INR value and warfarin dosage.Results: 1,Twenty six of 162 patients (16.05%) had postoperative complications during hospitalization, and thirteen of the twenty six patients were low cardiac output syndrome(LCOS), six cases were stopping bleeding by disclosing breast, three cases were cerebral air embolus, two cases were renal inadequacy, one was cerebral thrombosis, and another was upper gastrointestinal hemorrhage; Eight of 162 patients (4.94%) died, and four cases died of LCOS, one died of renal inadequacy, one died of refractory arrhythmia, one died of cerebral complication, and another died of unknown causes.2,126 cases were visited, the follow-up rate was 82% (126/154), up for seven to nineteen months. Six cases (4.16%) died, and three of them died of chronic heart failure, one died of prosthetic valve thrombosis, one died of anticoagulant bleeding, and another died of unknown causes. Thirteen cases had complications of hemorrhage and thromboembolism relating to anticoagulation. Ten cases (7.94%) were hemorrhage, and four cases of them were gingival bleeding, two cases were menorrhagia, two cases were cerebral hemorrhage, one was subcutaneous bleeding, and another was epistaxis; Three cases (2.38%) were thromboembolism, and two cases of them were central nervous embolization, and another was peripheral arterial embolization. All of the three patients were atrial fibrillation in preoperative diagnosis.3,Measured INR value is 2.39±1.27, daily dose of warfarin is 3.19±1.43mg.4,Eighteen cases of plasma concentrations of warfarin were measured, the observed INR values are as follows: three of them are smaller than 1.8 (Group A), ten are larger than 1.8 and smaller than 2.5 (Group B), the rest five are larger than 2.5 (Group C). The average warfarin plasma concentrations of Group C is higher than that of Group B, P<0.0005.5,There is seldom any linear correlation between INR value and plasma concentrations, R=0.65, P>0.1, and there is also no obvious linear correlation between INR value and the amount of daily warfarin dose taken, R=0.26, P>0.2.Conclusions: 1,Bleeding and thromboembolism which are relative to warfarin anticoagulation are the main complications after prosthetic heart valve replacement. The rate of bleeding is higher than that of thromboembolism.2,The INR range from 1.8 to 2.5 is suitable for the majority of Jiangxi citizens. The incidence of short-term complications from our review is close to which from national literature reports.3,Plasma concentrations of warfarin is an index of anticoagulation monitoring, which can give clinicians advice to adjust the dosage of warfarin safely and effectively. |
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