Gage B F, Fihn S D, White R H
Division of General Medical Science, Washington University School of Medicine, Campus Box 8005, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
Ann Intern Med. 2001 Mar 20;134(6):465-74. doi: 10.7326/0003-4819-134-6-200103200-00011.
In North America, atrial fibrillation is associated with at least 75 000 ischemic strokes each year. Most of these strokes occur in patients older than 75 years of age. The high incidence of stroke in very elderly persons reflects the increasing prevalence of atrial fibrillation that occurs with advanced age, the high incidence of stroke in elderly patients, and the failure of physicians to prescribe antithrombotic therapy in most of these patients. This failure is related to the increased risk for major hemorrhage with advanced age, obfuscating the decision to institute stroke prophylaxis with antithrombotic therapy. This case-based review describes the risk and benefits of prescribing antithrombotic therapy for a hypothetical 80-year-old man who has atrial fibrillation and hypertension, and it offers practical advice on managing warfarin therapy. After concluding that the benefits of warfarin outweigh its risks in this patient, we describe how to initiate warfarin therapy cautiously and how to monitor and dose the drug. We then review five recent randomized, controlled trials that document the increased risk for stroke when an international normalized ratio (INR) of less than 2.0 is targeted among patients with atrial fibrillation. Next, we make the case that cardioversion is not needed for this asymptomatic patient with chronic atrial fibrillation. Instead, we choose to leave the patient in atrial fibrillation and to control his ventricular rate with atenolol. Later, when the INR increases to 4.9, we advocate withholding one dose of warfarin and repeating the INR test. Finally, when the patient develops dental pain, we review the analgesic agents that are safe to take with warfarin and explain why warfarin therapy does not have to be interrupted during a subsequent dental extraction.
在北美，心房颤动每年至少导致75000例缺血性卒中。这些卒中大多发生在75岁以上的患者中。高龄人群中卒中的高发病率反映了房颤患病率随年龄增长而增加、老年患者卒中发病率高以及大多数此类患者的医生未开具抗血栓治疗药物。这种不作为与高龄患者大出血风险增加有关，使得决定是否采用抗血栓治疗进行卒中预防变得模糊不清。本病例回顾描述了为一名假设的患有房颤和高血压的80岁男性开具抗血栓治疗的风险和益处，并提供了管理华法林治疗的实用建议。在得出华法林对该患者的益处大于风险的结论后，我们描述了如何谨慎启动华法林治疗以及如何监测和调整药物剂量。然后，我们回顾了五项近期的随机对照试验，这些试验记录了房颤患者将国际标准化比值（INR）目标设定为低于2.0时卒中风险增加的情况。接下来，我们认为对于这位无症状的慢性房颤患者不需要进行心脏复律。相反，我们选择让患者维持房颤状态，并使用阿替洛尔控制其心室率。后来，当INR升至4.9时，我们主张停用一剂华法林并重复检测INR。最后，当患者出现牙痛时，我们回顾了与华法林同时服用安全的止痛药物，并解释了为什么在随后的拔牙过程中华法林治疗不必中断。
