OBJECTIVETo investigate the clinical application of anticoagulation treatment with warfarin after prosthetic heart valve replacement and compare the effect and safety of different anticoagulant intensities.

METHODSA total of 845 Chinese patients receiving oral warfarin for anticoagulant treatment after prosthetic heart valve replacement in Guangdong General Hospital between 2000 and 2008 were enrolled in this survey. The general data, clinical data, medications, international normalized ratio (INR) and results of echocardiogram of these patients were followed up to observe the incidence of complication of thrombo-embolism and such adverse effect as hemorrhage.

RESULTSAll the patients were of Han nationality, and Cantonese accounted for 88.04%. The daily mean maintenance dose of warfarin was 2.92∓0.88 mg in these patients with a median INR of 2.09∓0.39. Of these patients, 44.62% received low-intensity anticoagulant treatment with warfarin with the INR maintained between 1.5 and 2.0, and 56.45% had standard anticoagulant intensity with the INR maintained between 2.0 and 3.0. The total incidence of thrombo-embolism was 4.14%. Severe hemorrhage occurred in 14 cases (1.66%), most frequently in the alimentary tract. The events of hemorrhage were correlated to the type of prosthetic heart valve replacement, occurring more frequently in patients with mechanical prosthetic heart valve replacement than in those with biological ones. No significant difference was found in the incidence of thrombo-embolism and server hemorrhage between the two groups receiving low and standard intensity therapy anticoagulant.

CONCLUSIONThe effect and safety of low-intensity anticoagulant treatment are comparable to that of standard intensity treatment in Chinese Han patients, and anticoagulation treatment with warfarin is effective and safe to maintain the INR between 1.8-3.0.