Optimal therapeutic range for oral anticoagulants in Japanese patients with prosthetic heart valves: a preliminary report from a single institution using conversion from thrombotest to PT-INR |
| |
Authors: | Y Uetsuka Saichi Hosoda Hiroshi Kasanuki Masahiko Aosaki Kagari Murasaki Katsuyoshi Ooki Miyuki Inoue Etsuko Akiyama Masukazu Kitada |
| |
Institution: | (1) Department of Cardiology, The Heart Institute of Japan, Tokyo Women's Medical University, 8-1 Kawadacho, Shinjuku-ku, Tokyo 162-8666, Japan Tel. +81-3-3353-8111; Fax +81-3-5269-7445 e-mail: yoshiou@aol.com, JP;(2) Sakakibara Memorial Hospital, Tokyo, Japan, JP;(3) Yokohama National Hospital, Yokohama, Japan, JP;(4) Central Clinical Laboratories, Tokyo Women's Medical University, Tokyo, Japan, JP |
| |
Abstract: | The thrombotest (TT) technique has been widely used in Japan for monitoring oral anticoagulant therapy (OAT). The therapeutic
range was originally recommended to be 10%–25%. However, the International Committee for Standardization in Hematology/International
Committee on Thrombosis and Hemostasis (ICSH/ICTH) recommended using the international normalized ratio of prothrombin time
(PT-INR) for monitoring OAT. It is necessary to use a universal standard measure for monitoring OAT in accordance with the
ICSH/ISTH recommendation. We simultaneously measured TT and PT in blood samples from 1 157 patients on long-term warfarin
therapy, and studied the correlation between TT and PT-INR. An excellent linear correlation was obtained between TT-INR and
PT-INR with the regression equation PT-INR = 1.0420 TT-INR − 0.0987 (r = 0.905, P < 0.001). We also examined the correlation between the incidence of thromboembolism in 170 patients receiving warfarin therapy
after prosthetic valve replacement; 50.5% received concomitant antiplatelet therapy. Thromboembolism occurred in 9 of 170
patients during a mean follow-up period of 2.44 years. The average TT values in patients with and without thromboembolism
were 26.4% (PT-INR: 1.53) and 21.1% (1.73), respectively (P < 0.01). The incidence of thromboembolism did not differ significantly between patients on warfarin alone (average TT: 22.2%)
and those on warfarin and antiplatelet agent (average TT: 20.9%). Our results suggest that the incidence of thromboembolism
is low in Japan despite a less intensive regimen having been adopted.
Received: June 22, 2000 / Accepted: October 4, 2000 |
| |
Keywords: | Prothrombin time Thrombotest International normalized ratio Warfarin Oral anticoagulant therapy Mechanical valve |
本文献已被 PubMed SpringerLink 等数据库收录! |
|