Department of Advanced Biomedical Sciences, University Federico II, Naples, Italy.
Institute of Biostructure and Bioimaging, National Council of Research, Naples, Italy.
Eur J Nucl Med Mol Imaging. 2017 Dec;44(13):2266-2273. doi: 10.1007/s00259-017-3778-1. Epub 2017 Jul 22.
Cardiac sympathetic denervation may be detectable in patients with Anderson-Fabry disease (AFD), suggesting its usefulness for early detection of the disease. However, the relationship between sympathetic neuronal damage measured by I-metaiodobenzylguanidine (MIBG) imaging with myocardial fibrosis on cardiac magnetic resonance (CMR) is still unclear.
Cardiac sympathetic innervation was assessed by I-MIBG single-photon emission computed tomography (SPECT) in 25 patients with genetically proved AFD. Within one month from MIBG imaging, all patients underwent contrast-enhanced CMR. MIBG defect size and fibrosis size on CMR were measured for the left ventricle (LV) and expressed as %LV.
Patients were divided into three groups according to MIBG and CMR findings: (1) matched normal, without MIBG defects and without fibrosis on CMR (n = 10); (2) unmatched, with MIBG defect but without fibrosis (n = 5); and (3) matched abnormal, with MIBG defect and fibrosis (n = 10). The three groups did not differ with respect to age, gender, α-galactosidase, proteinuria, glomerular filtration rate, and troponin I, while New York Heart Association class (p = 0.008), LV hypertrophy (p = 0.05), and enzyme replacement therapy (p = 0.02) were different among groups. Although in patients with matched abnormal findings, there was a significant correlation between MIBG defect size and area of fibrosis at CMR (r = 0.98, p < 0.001), MIBG defect size was larger than fibrosis size (26 ± 23 vs. 18 ± 13%LV, p = 0.02).
Sympathetic neuronal damage is frequent in AFD patients, and it may precede myocardial damage, such as fibrosis. Thus, I-MIBG imaging can be considered a challenging technique for early detection of cardiac involvement in AFD.
心脏去交感神经支配可能在安德森-法布里病（AFD）患者中可检测到，这表明其对疾病的早期发现有用。然而，用 I-间碘苄胍（MIBG）成像测量的交感神经元损伤与心脏磁共振（CMR）上的心肌纤维化之间的关系仍不清楚。
对 25 名经基因证实的 AFD 患者进行 I-MIBG 单光子发射计算机断层扫描（SPECT）评估心脏交感神经支配。在 MIBG 成像后一个月内，所有患者均进行对比增强 CMR。测量左心室（LV）的 MIBG 缺陷大小和 CMR 上的纤维化大小，并表示为 %LV。
根据 MIBG 和 CMR 结果，患者分为三组：（1）匹配正常组，无 MIBG 缺陷且 CMR 上无纤维化（n=10）；（2）不匹配组，有 MIBG 缺陷但无纤维化（n=5）；（3）匹配异常组，有 MIBG 缺陷和纤维化（n=10）。三组在年龄、性别、α-半乳糖苷酶、蛋白尿、肾小球滤过率和肌钙蛋白 I 方面无差异，而纽约心脏协会分级（p=0.008）、LV 肥厚（p=0.05）和酶替代治疗（p=0.02）在各组之间不同。尽管在匹配异常发现的患者中，MIBG 缺陷大小与 CMR 上纤维化面积之间存在显著相关性（r=0.98，p<0.001），但 MIBG 缺陷大小大于纤维化大小（26±23 比 18±13%LV，p=0.02）。
在 AFD 患者中，交感神经元损伤很常见，并且可能早于纤维化等心肌损伤。因此，I-MIBG 成像可以被认为是早期发现 AFD 心脏受累的一项有挑战性的技术。
