Lizarazo Ortega David Andrés, Valderrama Bibiana Pinzón, González-Robledo Gina, Trujillo Patricia Bernal
Diagnostic Imaging Department, Fundación Santa Fe de Bogotá, Universidad El Bosque, 110111, Colombia.
Internal Medicine Department, Cardiology Service, Fundación Santa Fe de Bogotá, Universidad de Los Andes, 110111, Colombia.
Curr Med Imaging. 2023;19(4):402-406. doi: 10.2174/1573405618666220610091446.
Transthyretin amyloid cardiomyopathy was considered a rare pathology. However, recent studies show a significant prevalence in patients with degenerative aortic stenosis and heart failure with preserved ejection fraction.
An 85-year-old woman presented with a four-month history of pain in the rib cage with a history of diffuse large B-cell lymphoma of the oral cavity, essential thrombocytosis and dyslipidemia. She had no significant family history. A transthoracic echocardiogram showed degenerative aortic stenosis and normal systolic function with preserved left ventricular ejection fraction of 70%. Bone-avid tracer cardiac scintigraphy with technetium-99m-labeled hydroxymethylene diphosphonate with SPECT-CT documented grade two myocardial uptake according to the Perugini scale. MRI evidenced late patchy enhancement in the myocardium associated with diffuse subendocardial enhancement. Laboratory tests showed the absence of mutation in the transthyretin (TTR) gene, serum and urine immunofixation electrophoresis (IFE) negative for monoclonal protein and serum-free light chain (sFLC) assay with a normal kappa/lambda (K/L) ratio. All these findings were compatible with a non-invasive diagnosis of wild-type cardiac amyloidosis.
The accepted criteria for the definitive non-invasive diagnosis of amyloid cardiomyopathy are based on myocardial uptake by scintigraphy (with SPECT), serum and urine immunofixation electrophoresis, serum-free light chain assay and suggestive findings on echocardiography and/or MRI. Genetic testing should differentiate between ATTRv (v for variant) and ATTRwt (wt for wild type) forms.
转甲状腺素蛋白淀粉样变心肌病曾被认为是一种罕见疾病。然而，近期研究表明，在退行性主动脉瓣狭窄和射血分数保留的心力衰竭患者中，其患病率显著升高。
一名85岁女性，有4个月的胸廓疼痛病史，既往有口腔弥漫性大B细胞淋巴瘤、原发性血小板增多症和血脂异常病史。她没有明显的家族史。经胸超声心动图显示退行性主动脉瓣狭窄，收缩功能正常，左心室射血分数保留在70%。采用99m锝标记的羟亚甲基二膦酸盐进行骨亲和性示踪剂心肌闪烁显像及SPECT-CT检查，根据佩鲁吉尼量表记录为二级心肌摄取。MRI显示心肌晚期斑片状强化并伴有弥漫性心内膜下强化。实验室检查显示转甲状腺素蛋白（TTR）基因无突变，血清和尿液免疫固定电泳（IFE）未检测到单克隆蛋白，血清游离轻链（sFLC）检测kappa/ lambda（K/L）比值正常。所有这些发现均符合野生型心脏淀粉样变的无创诊断。
淀粉样变心肌病明确的无创诊断标准基于闪烁显像（SPECT）的心肌摄取、血清和尿液免疫固定电泳、血清游离轻链检测以及超声心动图和/或MRI的提示性表现。基因检测应区分ATTRv（v代表变异型）和ATTRwt（wt代表野生型）形式。
