Abstract

Age-related cardiac amyloidosis results from deposits of wild-type tranthyretin amyloid (ATTRwt) in cardiac tissue. ATTR may play a role in carpal tunnel syndrome (CTS) and in spinal stenosis (SS), indicating or presaging systemic amyloidosis. We investigated consecutive patients undergoing surgery for SS for ATTR deposition in the resected ligamentum flavum (LF) and concomitant risk of cardiac amyloidosis. Each surgical specimen (LF) was stained with Congo red, and if positive, the amyloid deposits were typed by mass spectrometry. Patients with positive specimens underwent standard of care evaluation with fat pad aspirates, serum and urine protein electrophoresis with immunofixation, free light-chain assay, TTR gene sequencing and technetium 99 m-pyrophosphate-scintigraphy. In 2018–2019, 324 patients underwent surgery for SS and 43 patients (13%) had ATTR in the LF with wild-type TTR gene sequences. Two cases of ATTRwt cardiac amyloidosis were diagnosed and received treatment. In this large series, ATTRwt was identified in 13% of the patients undergoing laminectomy for SS. Patients with amyloid in the ligamentum flavum were older and had a higher prevalence of CTS, suggesting a systemic form of ATTR amyloidosis involving connective tissue. Further prospective study of patients with SS at risk for systemic amyloidosis is warranted.

摘要

与年龄相关的心脏淀粉样变性是由野生型转甲状腺素蛋白淀粉样蛋白 (ATTRwt) 在心脏组织中的沉积引起的。ATTR 可能在腕管综合征 (CTS) 和椎管狭窄症 (SS) 中发挥作用，表明或预示系统性淀粉样变性。我们调查了连续接受 SS 手术的患者在切除的黄韧带 (LF) 中的 ATTR 沉积和伴随的心脏淀粉样变性风险。每个手术标本 (LF) 都用刚果红染色，如果呈阳性，则通过质谱对淀粉样蛋白沉积物进行分型。阳性标本患者接受标准护理评估，包括脂肪垫抽吸、血清和尿蛋白电泳免疫固定、游离轻链检测、TTR基因测序和锝 99 m-焦磷酸闪烁显像。2018-2019 年，324 名患者接受了 SS 手术，43 名患者（13%）在 LF 中具有野生型TTR基因序列的 ATTR。2例ATTRwt心脏淀粉样变性被诊断并接受治疗。在这个大型系列中，在 13% 的 SS 椎板切除术患者中发现了 ATTRwt。黄韧带中存在淀粉样蛋白的患者年龄较大，CTS 患病率较高，这表明 ATTR 淀粉样变性是一种累及结缔组织的系统性形式。有必要对有系统性淀粉样变性风险的 SS 患者进行进一步的前瞻性研究。