1 Department of Internal Medicine, 2 Department of Cardiology, St John Hospital and Medical Center Detroit, Michigan, USA ; 3 Baylor University Medical Center, Baylor Heart and Vascular Institute, Baylor Jack and Jane Hamilton Heart and Vascular Hospital, Dallas, Texas, USA.
Cardiovasc Diagn Ther. 2014 Jun;4(3):224-31. doi: 10.3978/j.issn.2223-3652.2014.03.07.
Dabigatran etexilate, was found to be effective for stroke prevention in patients with non-valvular atrial fibrillation. Given its predictable pharmacodynamics, laboratory monitoring is not required. Moreover, the risks of overall bleeding, intracranial bleeding, and life-threatening hemorrhage from dabigatran were found to be lower than warfarin. However, a higher risk of gastrointestinal (GI) bleeding caused by dabigatran from the randomized evaluation of long-term anticoagulant therapy (RE-LY) trial has raised the concern regarding clinical outcomes of patients with GI bleeding caused by dabigatran compared with warfarin.
We retrospectively studied patients who were hospitalized for GI bleeding from dabigatran compared with warfarin with therapeutic anticoagulation monitoring during 2009 to 2012. Initial laboratory findings at presentation, number of transfused packed red blood cells (PRBCs), acute kidney injury, clinical outcomes (e.g., hypotension, tachycardia), length of stay, and death were compared.
Thirteen patients taking dabigatran and 26 patients who were on warfarin with therapeutic international normalized ratio (INR) were hospitalized during the study period. Demographic data and baseline parameters between the two groups were not significantly different except for concurrent aspirin use (84.6% vs. 50%, P=0.036). Fifty-four percent of patients taking dabigatran did not have activated partial thromboplastin time (aPTT) level performed at presentation (7/13). The patients with GI bleeding from warfarin received significantly more PRBC transfusions compared with the dabigatran group (1.92±2.2 vs. 0.69±1.1 units, P=0.024). After controlling for initial hemoglobin and history of chronic kidney disease by using multivariate analysis, the patients in the warfarin group were likely to receive more PRBC. Hypotension at presentation was more common in GI bleeding caused by warfarin than dabigatran but the P value was insignificant (30.8% vs. 7.7%, P=0.11). Nevertheless, no differences in clinical outcomes or length of stay were found between the two groups.
From our data, the patients with GI bleeding from dabigatran were likely to receive fewer PRBC transfusions; however, clinical outcomes and length of stay were comparable to GI bleeding caused by warfarin. Our sample generalizes to an elderly population (mean age of 77.9±10 years old) with creatinine clearance (CrCl) >30 mL/min who experience GI bleeding during chronic anticoagulation.
达比加群酯已被证明可有效预防非瓣膜性心房颤动患者的中风。鉴于其可预测的药代动力学特性，无需进行实验室监测。此外，达比加群的总出血、颅内出血和危及生命的出血风险低于华法林。然而，来自随机评估长期抗凝治疗（RE-LY）试验的达比加群引起胃肠道（GI）出血的风险较高，这引起了人们对 GI 出血患者临床结局的关注与华法林相比，达比加群引起的 GI 出血。
我们回顾性研究了 2009 年至 2012 年期间因治疗性抗凝监测而住院的因 GI 出血而服用达比加群与华法林的患者。比较了入院时的初始实验室检查结果、输注的浓缩红细胞（PRBC）数量、急性肾损伤、临床结局（如低血压、心动过速）、住院时间和死亡。
研究期间，13 名服用达比加群的患者和 26 名服用华法林且国际标准化比值（INR）在治疗范围内的患者住院。两组之间的人口统计学数据和基线参数无显著差异，除同时使用阿司匹林（84.6%对 50%，P=0.036）外。54%服用达比加群的患者入院时未进行活化部分凝血活酶时间（aPTT）检查（7/13）。与达比加群组相比，华法林组的 GI 出血患者接受了更多的 PRBC 输血（1.92±2.2 对 0.69±1.1 单位，P=0.024）。通过多元分析控制初始血红蛋白和慢性肾脏病史后，华法林组更有可能接受 PRBC 输血。与达比加群相比，华法林引起的 GI 出血患者入院时低血压更常见，但差异无统计学意义（30.8%对 7.7%，P=0.11）。然而，两组的临床结局或住院时间无差异。
根据我们的数据，达比加群引起的 GI 出血患者更有可能接受较少的 PRBC 输血；然而，与华法林引起的 GI 出血相比，临床结局和住院时间相当。我们的样本适用于接受慢性抗凝治疗期间发生 GI 出血的年龄较大的人群（平均年龄 77.9±10 岁），且肌酐清除率（CrCl）>30 mL/min。
