Han Jason J, Gaffey Ann C, Sooppan Renganaden, Hung George, Venkataraman Chantel, Phillips Emily, Howard Jessica, McLean Rhondalyn, Acker Michael A, Atluri Pavan
From the *Division of Cardiovascular Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania; and †Division of Cardiovascular Medicine, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
ASAIO J. 2016 Mar-Apr;62(2):128-32. doi: 10.1097/MAT.0000000000000326.
Pump thrombosis (PT) is a common and potentially life-threatening complication among HeartMate II (HMII; Thoratec, Pleasanton, CA) patients. There have been efforts to correlate HMII geometry with higher risk of PT. The aim of this study was to test the validity of using HMII inflow cannula angle (ICA) and pump pocket depth (PPD) to predict PT. We performed a retrospective analysis of patients implanted with HMII left ventricular assist devices (LVADs) from January 2011 to March 2014 at our institution. Three blinded reviewers measured ICA and PPD from chest x-rays at postimplantation and most recent follow-up time points. The diagnosis of PT was visually confirmed upon device explantation by benchtop evaluation. HeartMate II was implanted in 90 patients. Sixteen (20%) patients experienced PT. There was no statistical difference between PT and non-PT patients in their initial ICAs (56.0° ± 10.1 vs. 54.6° ± 10.8, p = 0.63) and PPD (86.7 ± 24.9 mm vs. 81.1 ± 32.2 mm, p = 0.46). Prediction of PT using ICA and PPD by receiving operating characteristic was negative (area under curve (AUC) = 0.54 and 0.55, respectively). Changes in HMII geometry were measured over 112.5 (interquartile range = 34.3-337.3) days. A decrease in PPD was observed (p = 0.0001). Initial ICA was a significant predictor of future angle change and suggested a convergence toward the mean (55.4°) (analysis of variance p = 0.002). Pump thrombosis recurred in four (25%) patients. Postoperative ICA and PPD do not appear to predict PT in HMII patients in our experience. HeartMate II geometry changes over time secondary to remodeling with a decrease in PPD and a convergence toward the median in ICAs. Further investigation into the role of geometric ventricular assist device conformation postimplant may be warranted.
泵血栓形成（PT）是HeartMate II（HMII；Thoratec公司，普莱森顿，加利福尼亚州）患者中常见且可能危及生命的并发症。人们一直在努力将HMII的几何形状与PT的较高风险联系起来。本研究的目的是检验使用HMII流入插管角度（ICA）和泵袋深度（PPD）来预测PT的有效性。我们对2011年1月至2014年3月在我们机构植入HMII左心室辅助装置（LVAD）的患者进行了回顾性分析。三名盲法评审员在植入后和最近随访时间点通过胸部X光测量ICA和PPD。在设备取出时通过台式评估目视确认PT的诊断。90例患者植入了HeartMate II。16例（20%）患者发生了PT。PT患者和非PT患者的初始ICA（56.0°±10.1与54.6°±10.8，p = 0.63）和PPD（86.7±24.9 mm与81.1±32.2 mm，p = 0.46）之间无统计学差异。通过接受操作特征分析，使用ICA和PPD预测PT为阴性（曲线下面积（AUC）分别为0.54和0.55）。在112.5（四分位间距 = 34.3 - 337.3）天内测量了HMII几何形状的变化。观察到PPD减小（p = 0.0001）。初始ICA是未来角度变化的显著预测因子，并提示向平均值（55.4°）收敛（方差分析p = 0.002）。4例（25%）患者泵血栓形成复发。根据我们的经验，术后ICA和PPD似乎不能预测HMII患者的PT。由于重塑，HeartMate II的几何形状随时间变化，PPD减小，ICA向中位数收敛。可能有必要进一步研究植入后几何形状的心室辅助装置构象的作用。
