From the Department of Cardiovascular Surgery, Mayo Clinic Rochester, Rochester, Minnesota.
Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria.
ASAIO J. 2018 Nov/Dec;64(6):e161-e165. doi: 10.1097/MAT.0000000000000845.
International normalized ratio (INR) measurements manage risks of bleeding and clotting sequelae in the population with left ventricular assist device (LVAD). Studies suggest that point-of-care (POC) INR does not significantly differ from plasma INR (P-INR) values in other patient populations, although this has not been validated in a multicenter LVAD study. We sought to determine whether POC-INR and P-INR values differ significantly in the LVAD population and reviewed patients with permanent LVAD implantation at seven institutions internationally. Our cohort comprised of 279 paired POC-INR and P-INR checks in patients supported on average 630 ± 598 days postimplant with predominately HeartWare, HeartMate II, and HeartMate III devices. The population averaged 57.9 years of age, and there were 86.7% male. We found no statistically significant difference between POC-INR and P-INR values. International normalized ratio accuracy correlated weakly with the time between INR measurements (p < 0.001). When the time difference was less than 4 hours, the difference between INR pairs was significantly lower than measurements greater than 8 hours (p = 0.006). There was no statistically significant difference when comparing paired INR values and time after implant to INR check (p = 0.43), age (p = 0.12), known coagulopathy (p = 0.12), bleeding history (p = 0.22), or thrombosis history (p = 0.34). This is the first large multicenter international study comparing POC-INR and P-INR measurements in patients with LVAD and found no statistically significant difference between either methods, particularly when measured within less than 4 hours of each other.
国际标准化比值（INR）测量可管理左心室辅助装置（LVAD）人群中的出血和血栓后遗症风险。研究表明，即时检测（POC）INR 与其他患者群体中的血浆 INR（P-INR）值没有显著差异，尽管这尚未在多中心 LVAD 研究中得到验证。我们旨在确定 POC-INR 和 P-INR 值在 LVAD 人群中是否存在显著差异，并回顾了国际上 7 家机构接受永久性 LVAD 植入的患者。我们的队列包括 279 对接受平均植入后 630±598 天支持的 LVAD 患者的 POC-INR 和 P-INR 检查，主要使用 HeartWare、HeartMate II 和 HeartMate III 设备。该人群的平均年龄为 57.9 岁，男性占 86.7%。我们发现 POC-INR 和 P-INR 值之间没有统计学上的显著差异。INR 准确性与 INR 测量之间的时间呈弱相关（p<0.001）。当时间差小于 4 小时时，INR 对之间的差异明显低于大于 8 小时的测量（p=0.006）。当比较植入后时间与 INR 检查的 INR 对值时，没有统计学上的显著差异（p=0.43），年龄（p=0.12），已知凝血障碍（p=0.12），出血史（p=0.22）或血栓形成史（p=0.34）。这是第一项比较 LVAD 患者 POC-INR 和 P-INR 测量值的大型多中心国际研究，未发现两种方法之间存在统计学上的显著差异，特别是当彼此之间的测量时间小于 4 小时时。
