Vora Amit
J Assoc Physicians India. 2013 Dec;61(12):900-2.
Atrial fibrillation (AF) affects millions worldwide. Stroke is the most devastating complication of AF and is associated with a huge disease burden. As a preventive measure, anticoagulant therapy is recommended for most AF patients based on presence of stroke risk factors. For the past six decades warfarin remained the gold standard for stroke prevention in AF (SPAF). However, it is associated with numerous limitations such as a high risk of drug-drug, drug-food interactions and need for frequent INR (2-3) monitoring. Novel oral anticoagulant (NOAC) dabigatran etexilate is a selective, specific, reversible direct thrombin inhibitor that has been approved in India for SPAF and primary venous thromboembolism prevention. The efficacy and safety of dabigatran in AF has been established the "Randomized Evaluation of Long-Term Anticoagulant Therapy (RE-LY)", a randomized clinical trial. RE-LY (n = 18,113) demonstrated that the efficacy of dabigatran 110 mg BID was as good as well controlled warfarin and dabigatran 150 mg BID reduced the risk of ischaemic stroke by 25% (P = 0.03). Till date, 150mg dabigatran is the only NOAC offering a superior reduction in most commonly seen ischemic strokes due to AF compared to warfarin. Additionally, both doses of dabigatran significantly reduced the risk of total bleeds, intracranial, and life threatening bleeds versus warfarin (p < 0.05). Dabigatran has advantages over warfarin including predictable pharmacokinetic/pharmacodynamic profile, minimal drug-drug and no drug-food interactions while no monitoring is needed.The 150 mg dose of dabigatran should be considered in younger patients with a low risk of bleeding and good renal function to achieve a superior ischemic stroke reduction, whereas, the 110 mg dose should be considered in elderly patients, those with mild to moderate renal function or those with high risk of bleeding.
心房颤动(AF)在全球影响着数百万人。中风是AF最具破坏性的并发症,且与巨大的疾病负担相关。作为一种预防措施,基于中风风险因素的存在,大多数AF患者推荐使用抗凝治疗。在过去的六十年里,华法林一直是AF患者预防中风(SPAF)的金标准。然而,它存在许多局限性,如药物相互作用、药物与食物相互作用的高风险以及需要频繁监测国际标准化比值(INR)(2 - 3)。新型口服抗凝药(NOAC)达比加群酯是一种选择性、特异性、可逆的直接凝血酶抑制剂,已在印度被批准用于SPAF和预防原发性静脉血栓栓塞。达比加群在AF中的疗效和安全性已在一项随机临床试验“长期抗凝治疗随机评估(RE - LY)”中得到证实。RE - LY(n = 18,113)研究表明,达比加群110 mg每日两次的疗效与良好控制的华法林相当,达比加群150 mg每日两次使缺血性中风风险降低了25%(P = 0.03)。迄今为止,与华法林相比,150mg达比加群是唯一一种能更显著降低AF常见缺血性中风风险的NOAC。此外,与华法林相比,达比加群的两种剂量均显著降低了总出血、颅内出血和危及生命出血的风险(p < 0.05)。达比加群优于华法林,包括可预测的药代动力学/药效学特征、最小的药物相互作用且不存在药物与食物相互作用,同时无需监测。对于出血风险低且肾功能良好的年轻患者,应考虑使用150 mg剂量的达比加群以实现更好的缺血性中风风险降低,而对于老年患者、轻度至中度肾功能患者或出血风险高的患者,应考虑使用110 mg剂量。