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Journal of the American College of... Jun 2020Technetium-labeled cardiac scintigraphy (i.e., Tc-PYP scan) has been repurposed for the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM). Validated in cohorts... (Review)
Review
Technetium-labeled cardiac scintigraphy (i.e., Tc-PYP scan) has been repurposed for the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM). Validated in cohorts of patients with heart failure and echocardiographic and/or cardiac magnetic resonance imaging findings suggestive of cardiac amyloidosis, cardiac scintigraphy can confirm the diagnosis of ATTR-CM only when combined with blood and urine testing to exclude a monoclonal protein. Multisocietal guidelines support the nonbiopsy diagnosis of ATTR-CM using cardiac scintigraphy, yet emphasize its use in the appropriate clinical context and the crucial need to rule out light chain amyloid cardiomyopathy. Although increased awareness of ATTR-CM and the advent of effective therapy have led to rapid adoption of diagnostic scintigraphy, there is heterogeneity in adherence to consensus guidelines. This perspective outlines clinical scenarios wherein findings on technetium-labeled cardiac scintigraphy have been misinterpreted, reviews causes of false-negative and false-positive results, and provides strategies to avoid costly and potentially fatal misdiagnoses.
Topics: Amyloidosis; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Cardiomyopathies; Heart Failure; Humans; Magnetic Resonance Imaging, Cine; Organotechnetium Compounds; Radioactive Tracers; Radionuclide Imaging; Technetium
PubMed: 32498813
DOI: 10.1016/j.jacc.2020.04.022 -
ESC Heart Failure Feb 2022Transthyretin amyloid cardiomyopathy (ATTR-CM) is caused by the cardiac deposition of insoluble amyloid fibrils formed by misfolded transthyretin proteins and is... (Review)
Review
Transthyretin amyloid cardiomyopathy (ATTR-CM) is caused by the cardiac deposition of insoluble amyloid fibrils formed by misfolded transthyretin proteins and is associated with various cardiac symptoms, such as progressive heart failure, conduction disturbance, and arrhythmia. The implementation of technetium ( Tc)-labelled bone radiotracer scintigraphy for diagnosing ATTR-CM has enabled accurate diagnosis of the disease with high sensitivity and specificity and positioned this diagnostic modality as an integral part of disease diagnostic algorithms. In 2020, Tc-pyrophosphate scintigraphy received exceptional approval for Japanese national health insurance reimbursement as a diagnostic method of ATTR-CM. Nevertheless, the utility of Tc-labelled bone radiotracer scintigraphy and the importance of an early diagnosis of suspected ATTR-CM using this technique have yet to be internalized as common practice by general cardiologists, and guidance on daily clinical scenarios to consider this technique for a diagnosis of suspected ATTR-CM is warranted. In this review, we discuss the utility of Tc-labelled bone radiotracer scintigraphy for the early diagnosis of ATTR-CM based on published literature and the outcomes of an advisory board meeting. This review also discusses clinical scenarios that could support early diagnosis of suspected ATTR-CM as well as common pitfalls, correct implementation, and future perspectives of Tc-labelled bone radiotracer scintigraphy in daily clinical practice. The clinical scenarios to consider Tc-labelled bone radiotracer scintigraphy in daily practice may include, but are not limited to, patients with a family history of the hereditary type of disease; elderly patients (aged ≥60 years) with unexplained cardiac findings (e.g. cardiac hypertrophy associated with abnormalities on an electrocardiogram, heart failure with preserved ejection fraction associated with unexplained left ventricular hypertrophy, and heart failure with reduced ejection fraction associated with atrial fibrillation and left ventricular hypertrophy); and patients with cardiac hypertrophy associated with diastolic dysfunction, right ventricular/interatrial septum/valve thickness, left ventricular sparkling, or apical sparing. Cardiac hypertrophy and persistent elevation in cardiac troponin in elderly patients are also suggestive of ATTR-CM. Tc-labelled bone radiotracer scintigraphy is also recommended in patients with characteristic cardiac magnetic resonance findings (e.g. diffuse subendocardial late gadolinium enhancement patterns, native T1 increase, and increase in extracellular volume) or patients with cardiac hypertrophy and bilateral carpal tunnel syndrome.
Topics: Aged; Amyloid Neuropathies, Familial; Cardiomyopathies; Contrast Media; Diphosphates; Early Diagnosis; Gadolinium; Humans; Middle Aged; Prealbumin; Radionuclide Imaging; Technetium
PubMed: 34841715
DOI: 10.1002/ehf2.13693 -
The Quarterly Journal of Nuclear... Jun 2023
Topics: Humans; Diagnostic Imaging; Parathyroid Glands; Technetium Tc 99m Sestamibi
PubMed: 36748986
DOI: 10.23736/S1824-4785.23.03511-2