Kitamura M, Koyanagi H, Kawada S, Hosoda Y, Kurosawa H, Takeuchi Y, Kawase M, Wanibuchi Y
Tokyo Area Anticoagulation Study (TAS) Group, Japan.
Kyobu Geka. 1999 Nov;52(12):1001-4.
This study was undertaken to assess optimum anticoagulation control after bileaflet mechanical valve replacement by using the international normalized ratio of prothrombin time (PT-INR). From January to December 1995, 261 patients (pts) underwent mechanical valve replacement in the aortic (n = 95), mitral (n = 126), aortomitral (n = 39) or isolated tricuspid (n = 1) valve position in 8 medical centers in Tokyo, Japan. The St. Jude Medical valves were implanted in 184 pts and the Carbomedics valves in 77. There were 17 valve-related events as follows: 11 thromboembolic events (3.62%/pt-yr) including 10 transient ischemic attacks. 5 non-fatal bleeding events (1.65%/pt-yr), 2 reoperations (0.66%/pt-yr). At 18 postoperative months, free rates from all deaths (actuarial survival) thromboembolism, reoperation and all valve-related events were 95.3%, 95.7%, 98.7% and 88.9%, respectively. Under anticoagulant therapy, thrombin-antithrombin III complex and D-dimmer remained in high levels at 1 month after operation, and both values decreased to the control level at 6 months. In patients with thromboembolic events, PT-INR tended to be less than 2.0. The patients with bleeding events showed some increase of PT-INP or received anti-platelet agents. The 5 to 95 percentile of PT-INR at 6 months was 1.2 to 3.0 in the patients without valve-related events. These results suggested that optimum range of PT-INR might be between 1.2 and 3.0 after bileaflet mechanical valve replacement in patients without high risk of thromboembolism and between 2.0 and 3.0 in patients with the high risk.
本研究旨在通过使用凝血酶原时间国际标准化比值（PT-INR）评估双叶机械瓣膜置换术后的最佳抗凝控制。1995年1月至12月，261例患者在日本东京的8家医疗中心接受了主动脉瓣（n = 95）、二尖瓣（n = 126）、主动脉二尖瓣（n = 39）或孤立三尖瓣（n = 1）位置的机械瓣膜置换术。184例患者植入了圣犹达医疗瓣膜，77例患者植入了卡波美迪克斯瓣膜。发生了17例与瓣膜相关的事件，具体如下：11例血栓栓塞事件（3.62%/患者年），包括10例短暂性脑缺血发作；5例非致命性出血事件（1.65%/患者年），2例再次手术（0.66%/患者年）。术后18个月，所有死亡（精算生存率）、血栓栓塞、再次手术和所有与瓣膜相关事件的无事件发生率分别为95.3%、95.7%、98.7%和88.9%。在抗凝治疗下，凝血酶-抗凝血酶III复合物和D-二聚体在术后1个月时仍处于高水平，两者在6个月时均降至对照水平。在发生血栓栓塞事件的患者中，PT-INR往往低于2.0。发生出血事件的患者PT-INR有所升高或接受了抗血小板药物治疗。在无瓣膜相关事件的患者中，6个月时PT-INR的第5至95百分位数为1.2至3.0。这些结果表明，在无血栓栓塞高风险的患者中，双叶机械瓣膜置换术后PT-INR的最佳范围可能在1.2至3.0之间，而在高风险患者中则在2.0至3.0之间。
