Department of Radiology and Nuclear Medicine, Centre Hospitalier de l'Université de Montréal (CHUM), Montréal, Canada.
University of Ottawa Heart Institute, Division of Cardiology, Department of Medicine, Ottawa, Canada.
Bone Joint J. 2019 May;101-B(5):540-546. doi: 10.1302/0301-620X.101B5.BJJ-2018-1478.R1.
Cardiac magnetic resonance (CMR) was used to assess whether cardiac function or tissue composition was affected in patients with well-functioning metal-on-metal hip resurfacing arthroplasties (MoMHRA) when compared with a group of controls, and to assess if metal ion levels correlated with any of the functional or structural parameters studied.
In all, 30 participants with no significant cardiac history were enrolled: 20 patients with well-functioning MoMHRA at mean follow-up of 8.3 years post-procedure (ten unilateral, ten bilateral; 17 men, three women) and a case-matched control group of ten non-MoM total hip arthroplasty patients (six men, four women). The mean age of the whole cohort (study group and controls) at the time of surgery was 50.6 years (41.0 to 64.0). Serum levels of cobalt and chromium were measured, and all patients underwent CMR imaging, including cine, T2* measurements, T1 and T2 mapping, late gadolinium enhancement, and strain measurements.
None of the MoMHRA patients showed clinically significant cardiac functional abnormality. The MoMHRA patients had larger indexed right and left end diastolic volumes (left ventricular (LV): 74 ml/m 67 ml/m, p = 0.045; right ventricular: 80 ml/m 71 ml/m, p = 0.02). There was a small decrease in T2 time in the MoMHRA patients (median 49 ms 54 ms; p = 0.0003). Higher metal ion levels were associated with larger LV volumes and with shorter T2 time.
Although cardiac function is not clinically adversely affected in patients with well-functioning MoMHRA, modern imaging is able to demonstrate subtle changes in structure and function of the heart. As these changes correlate with systemic ion measurements, they may be consequences of wear debris deposition. Longer, longitudinal studies are necessary to determine whether cardiac function will become affected. Cite this article: 2019;101-B:540-546.
心脏磁共振（CMR）用于评估功能良好的金属对金属髋关节表面置换术（MoMHRA）患者与对照组相比心脏功能或组织成分是否受到影响，并评估金属离子水平是否与任何研究的功能或结构参数相关。
共有 30 名无明显心脏病史的参与者入组：20 名 MoMHRA 功能良好的患者，平均术后 8.3 年（10 例单侧，10 例双侧；17 例男性，3 例女性）和 10 例非 MoM 全髋关节置换术患者的病例匹配对照组（6 例男性，4 例女性）。整个队列（研究组和对照组）在手术时的平均年龄为 50.6 岁（41.0 至 64.0 岁）。测量了钴和铬的血清水平，所有患者均进行了 CMR 成像，包括电影、T2*测量、T1 和 T2 映射、晚期钆增强和应变测量。
MoMHRA 患者均无临床显著的心脏功能异常。MoMHRA 患者的左、右舒张末期容积指数较大（左心室：74ml/m3 71ml/m3，p=0.045；右心室：80ml/m3 71ml/m3，p=0.02）。MoMHRA 患者的 T2 时间略有缩短（中位数 49ms 54ms；p=0.0003）。较高的金属离子水平与较大的 LV 容积和较短的 T2 时间相关。
尽管功能良好的 MoMHRA 患者的心脏功能并未受到临床不良影响，但现代影像学能够显示心脏结构和功能的细微变化。由于这些变化与系统离子测量相关，它们可能是磨损碎片沉积的结果。需要进行更长时间的纵向研究，以确定心脏功能是否会受到影响。
