Roberts Gregory, Razooqi Rasha, Quinn Stephen
1 Flinders Medical Centre, Bedford Park, South Australia, Australia.
2 Flinders University, Bedford Park, South Australia, Australia.
Ann Pharmacother. 2017 Mar;51(3):219-225. doi: 10.1177/1060028016676830. Epub 2016 Oct 26.
The immediate postoperative warfarin sensitivity for patients receiving heart valve prostheses is increased. Established warfarin initiation protocols may lack clinical applicability, resulting in dosing based on clinical judgment.
To compare current practice for warfarin initiation with a known warfarin initiation protocol, with doses proportionally reduced to account for the increased postoperative sensitivity.
We compared the Mechanical Heart Valve Warfarin Initiation Protocol (Protocol group) with current practice (clinical judgment-Empirical group) for patients receiving mechanical heart valves in an observational before-and-after format. End points were the time to achieve a stable therapeutic international normalized ratio (INR), doses held in the first 6 days, and overanticoagulation in the first 6 days.
The Protocol group (n = 37) achieved a stable INR more rapidly than the Empirical group (n = 77; median times 5.1 and 8.7 days, respectively; P = 0.002). Multivariable analysis indicated that the Protocol group (hazard ratio [HR] = 2.22; P = 0.005) and men (HR = 1.76; P = 0.043) more rapidly achieved a stable therapeutic INR. Age, serum albumin, amiodarone, presence of severe heart failure, and surgery type had no impact. Protocol patients had fewer doses held (1.1% vs 10.1%, P < 0.001) and no difference in overanticoagulation (2.7% vs 9.1%, P = 0.27).
The Mechanical Heart Valve Warfarin Initiation Protocol provided a reliable approach to initiating warfarin in patients receiving mechanical aortic or mitral valves.
接受心脏瓣膜置换术的患者术后对华法林的敏感性会立即增加。既定的华法林起始方案可能缺乏临床适用性，导致剂量基于临床判断。
将当前华法林起始用药的做法与已知的华法林起始方案进行比较，并按比例减少剂量以应对术后增加的敏感性。
我们采用前后观察的形式，将机械心脏瓣膜华法林起始方案（方案组）与当前做法（临床判断-经验组）用于接受机械心脏瓣膜置换术的患者。终点指标为达到稳定治疗性国际标准化比值（INR）的时间、前6天暂停的剂量以及前6天的抗凝过度情况。
方案组（n = 37）比经验组（n = 77）更快达到稳定的INR（中位时间分别为5.1天和8.7天；P = 0.002）。多变量分析表明，方案组（风险比[HR] = 2.22；P = 0.005）和男性（HR = 1.76；P = 0.043）更快达到稳定的治疗性INR。年龄、血清白蛋白、胺碘酮、严重心力衰竭的存在以及手术类型均无影响。方案组患者暂停的剂量更少（1.1%对10.1%，P < 0.001），抗凝过度情况无差异（2.7%对9.1%，P = 0.27）。
机械心脏瓣膜华法林起始方案为接受机械主动脉瓣或二尖瓣置换术的患者启动华法林治疗提供了一种可靠的方法。
