Teigen Levi M, John Ranjit, Kuchnia Adam J, Nagel Emily M, Earthman Carrie P, Kealhofer Jessica, Martin Cindy, Cogswell Rebecca
From the Food Science and Nutrition, University of Minnesota-Twin Cities, Minneapolis (L.T., A.J.K., E.M.N., C.P.E.); and Department of Cardiothoracic Surgery, Division of Surgery (R.J.) and Department of Medicine, Division of Cardiology (J.K., C.M., R.C.), University of Minnesota, Minneapolis.
Circ Heart Fail. 2017 Sep;10(9). doi: 10.1161/CIRCHEARTFAILURE.117.004069.
Skeletal muscle mass decreases in end-stage heart failure and is predictive of clinical outcomes in several disease states. Skeletal muscle attenuation and quantity as quantified on preoperative chest computed tomographic scans may be predictive of mortality after continuous flow (CF) left ventricular assist device (LVAD) implantation.
A single-center continuous flow-LVAD database (n=354) was used to identify patients with chest computed tomographies performed in the 3 months before LVAD implantation (n=143). Among patients with computed tomography data available, unilateral pectoralis muscle mass indexed to body surface area and attenuation (approximated by mean Hounsfield units [PHU]) were measured in each patient with a high intrarater and inter-rater reliability (intraclass correlation coefficients 0.98 and 0.97, respectively). Multivariate Cox regression analyses were performed, censoring at cardiac transplantation, to assess the impact of preoperative pectoralis muscle index and pectoralis muscle mean Hounsfield unit on survival after LVAD implantation. Each unit increase in pectoralis muscle index was associated with a 27% reduction in the hazard of death after LVAD (adjusted hazard ratio, 0.73; 95% confidence interval, 0.58-0.92; =0.007). Each 5-U increase in pectoralis muscle mean Hounsfield unit was associated with a 22% reduction in the hazard of death after LVAD (adjusted hazard ratio, 0.78; 95% confidence interval, 0.68-0.89; <0.0001). Pectoralis muscle index and pectoralis muscle mean Hounsfield unit outperformed other traditional measures in the data set, including the HeartMate II risk score.
Pectoralis muscle size and attenuation were powerful predictors of outcomes after LVAD implantation in this data set. This one time, repeatable, internal assessment of patient substrate added valuable prognostic information that was not available on standard preoperative testing.
终末期心力衰竭患者骨骼肌质量会下降，且在多种疾病状态下可预测临床结局。术前胸部计算机断层扫描（CT）所量化的骨骼肌衰减和数量可能预测连续血流（CF）左心室辅助装置（LVAD）植入术后的死亡率。
使用单中心连续血流LVAD数据库（n = 354）来识别在LVAD植入前3个月内进行过胸部CT检查的患者（n = 143）。在有CT数据的患者中，测量每位患者的单侧胸肌质量（以体表面积指数化）和衰减程度（通过平均亨氏单位[PHU]近似），测量的组内和组间可靠性均较高（组内相关系数分别为0.98和0.97）。进行多因素Cox回归分析，并以心脏移植作为删失事件，以评估术前胸肌指数和胸肌平均亨氏单位对LVAD植入术后生存的影响。胸肌指数每增加1个单位，与LVAD植入后死亡风险降低27%相关（调整后风险比为0.73；95%置信区间为0.58 - 0.92；P = 0.007）。胸肌平均亨氏单位每增加5个单位，与LVAD植入后死亡风险降低22%相关（调整后风险比为0.78；95%置信区间为0.68 - 0.89；P < 0.0001）。在该数据集中，胸肌指数和胸肌平均亨氏单位比其他传统指标表现更好，包括HeartMate II风险评分。
在该数据集中，胸肌大小和衰减程度是LVAD植入术后结局的有力预测指标。这种对患者基础情况的一次性、可重复的内部评估增加了标准术前检查中无法获得的有价值的预后信息。
