BackgroundSkeletal muscle alterations are associated with higher mortality and morbidity in patients with liver cirrhosis. Assessing these changes seems to be a promising method for identifying patients at a high risk of poor outcomes following liver transplantation (LT). This is particularly important given the current global shortage of organ donors. However, evidence of the impact of these alterations on the prognosis of patients undergoing LT is inconclusive. The aim of our prospective study was to evaluate the impact of skeletal muscle changes, reflected in sarcopenia, myosteatosis and metabolic changes in the calf muscles, on perioperative outcomes and long‐term survival after LT. We also sought to determine the posttransplant evolution of the resting muscle metabolism.MethodsWe examined 134 adult LT candidates. Of these, 105 underwent LT. Sarcopenia and myosteatosis were diagnosed by measuring the skeletal muscle index and mean psoas muscle radiation attenuation, respectively, which were obtained from computed tomography (CT) scans taken during pretransplant assessment. Additionally, patients underwent 31P MR spectroscopy (MRS) of the calf muscles at rest before LT and 6, 12 and 24 months thereafter. The median follow‐up was 6 years.ResultsPatients with abnormal 31P MRS results and CT‐diagnosed myosteatosis prior to LT had significantly worse long‐term survival after LT (hazard ratio (HR), 3.36; 95% confidence interval (CI), 1.48–7.60; p = 0.0021 and HR, 2.58; 95% CI, 1.06–6.29; p = 0.03, respectively). Multivariable analysis showed that abnormal 31P MR spectra (HR, 3.40; 95% CI, 1.50–7.71; p = 0.003) were a better predictor of worse long‐term survival after LT than myosteatosis (HR, 2.78; 95% CI, 1.14–6.78; p = 0.025). Patients with abnormal 31P MR spectra had higher blood loss during LT (p = 0.038), required a higher number of red blood cell transfusions (p = 0.006) and stayed longer in ICU (p = 0.041) and hospital (p = 0.007). Myosteatosis was associated with more revision surgeries following LT (p = 0.038) and a higher number of received red blood cell transfusion units (p = 0.002). Sarcopenia had no significant effect on posttransplant patient survival. An improvement in the resting metabolism of the calf muscles was observed at 12 and 24 months after LT.ConclusionsAbnormal 31P MRS results of calf muscles were superior to CT‐based diagnosis of myosteatosis and sarcopenia in predicting perioperative complications and long‐term survival after LT. Resting muscle metabolism normalized 1 year after LT in most recipients.

中文翻译：

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骨骼肌 31P MR 波谱在预测肝移植后患者生存率方面优于 CT


背景骨骼肌改变与肝硬化患者较高的死亡率和发病率相关。评估这些变化似乎是一种很有前途的方法，可以识别肝移植 （LT） 后不良结局的高风险患者。鉴于当前全球器官捐献者短缺，这一点尤为重要。然而，这些改变对接受 LT 的患者预后影响的证据尚无定论。我们前瞻性研究的目的是评估骨骼肌变化对 LT 后围手术期结局和长期生存率的影响，这些变化反映在肌肉减少症、肌脂肪变性和代谢变化中。我们还试图确定静息肌代谢的移植后演变。方法我们检查了 134 名成人 LT 候选人。其中，105 例接受了 LT。肌肉减少症和肌脂肪变性分别通过测量骨骼肌指数和平均腰大肌放射衰减来诊断，这些指标是从移植前评估期间进行的计算机断层扫描 （CT） 扫描中获得的。此外，患者在 LT 前和之后 6 、 12 和 24 个月接受了静息时小腿肌肉的 31P MR 光谱 （MRS）。中位随访时间为 6 年。结果31P MRS 结果异常且 LT 前 CT 诊断为脂肪变性的患者在 LT 后的长期生存率显著较差（风险比 （HR），3.36;95% 置信区间 （CI），1.48-7.60;p = 0.0021 和 HR，2.58;95% CI，1.06-6.29;p = 0.03，分别为）。多变量分析显示，异常的 31P MR 谱 （HR， 3.40;95% CI， 1.50–7.71;p = 0.003） 是比肌脂肪变性 （HR， 2.78;95% CI， 1.14–6.78;p = 0.025） 更好的 LT 后长期生存率较差的预测因子。 31P MR 谱异常的患者在 LT 期间失血量较高 （p = 0.038），需要更多的红细胞输注次数 （p = 0.006），并且在 ICU （p = 0.041） 和医院 （p = 0.007） 中停留的时间更长。肌脂肪变性与 LT 后更多的翻修手术 （p = 0.038） 和更多的接受红细胞输注单位 （p = 0.002） 相关。肌肉减少症对移植后患者生存率无显著影响。在 LT 后 12 个月和 24 个月观察到小腿肌肉的静息代谢有所改善。结论小腿肌肉 31P MRS 结果异常在预测围手术期并发症和 LT 后长期生存率方面优于基于 CT 的肌脂肪变性和肌肉减少症诊断。大多数受者在 LT 后 1 年静息肌代谢恢复正常。