Amyloid cardiomyopathy

INTRODUCTION: Transthyretin amyloidosis (ATTR) is a progressive, heterogeneous rare disease manifesting as ATTR polyneuropathy (ATTR-PN), ATTR cardiomyopathy (ATTR-CM), or a mixed phenotype. Tafamidis meglumine (20 mg po qd) is approved in some markets to delay neurologic progression in ATTR-PN, while high-dose tafamidis (80/61 mg po qd) is approved worldwide to reduce cardiovascular mortality and cardiovascular-related hospitalization in ATTR-CM. The objective of this study was to assess the real-world benefit of high-dose tafamidis for delaying neurologic progression in patients with mixed-phenotype variant ATTR-CM (ATTRv-CM)...

AL amyloidosis is a life-threatening disease caused by deposition of immunoglobulin light chains. Whilst the mechanisms underlying light chains amyloidogenesis in vivo remain unclear, several studies have highlighted the role that tissue environment and structural amyloidogenicity of individual light chains have in the disease pathogenesis. AL natural deposits contain both full-length light chains and fragments encompassing the variable domain (VL ) as well as different length segments of the constant region (CL ), thus highlighting the relevance that proteolysis may have in the fibrillogenesis pathway...

ATTR amyloidosis results from the conversion of transthyretin into amyloid fibrils that deposit in tissues causing organ failure and death. This conversion is facilitated by mutations in ATTRv amyloidosis, or aging in ATTRwt amyloidosis. ATTRv amyloidosis exhibits extreme phenotypic variability, whereas ATTRwt amyloidosis presentation is consistent and predictable. Previously, we found an unprecedented structural variability in cardiac amyloid fibrils from polyneuropathic ATTRv-I84S patients. In contrast, cardiac fibrils from five genotypically-different patients with cardiomyopathy or mixed phenotypes are structurally homogeneous...

BACKGROUND: Cardiac amyloidosis (CA) is characterized by the extracellular deposition of misfolded protein in the heart. Precise identification of the amyloid type is often challenging, but critical, since the treatment and prognosis depend on the disease form and the type of deposited amyloid. Coexistence of clinical conditions such as old age, monoclonal gammopathy, chronic inflammation, or peripheral neuropathy in a patient with cardiomyopathy creates a differential diagnosis between the major types of CA: amyloidosis light chains (AL), amyloidosis transthyretin (ATTR) and amyloidosis A (AA)...

INTRODUCTION: Fine-needle aspiration (FNA) of abdominal fibroadipose tissue is a commonly utilized method for the detection of amyloidosis. While generally regarded as an accurate and specific detection method, the sensitivity is variable. The objective of this study was to investigate the performance of fat pad FNAs in detecting amyloidosis relative to other tissue biopsies. MATERIALS AND METHODS: Fat pad FNA results from January 1, 2014, to December 31, 2022, were catalogued...

AIMS: Despite their potential, sodium-glucose cotransporter 2 inhibitors (SGLT2i) have not been well-studied in transthyretin amyloid cardiomyopathy (ATTR-CM) as randomized trials have excluded patients with this morbid disease. We performed a retrospective study assessing the short-term efficacy and safety of SGLT2i in ATTR-CM. METHODS AND RESULTS: We screened consecutive patients seen at a tertiary care centre and identified 87 ATTR-CM patients treated with SGLT2i and 95 untreated control patients...

Increasing evidence suggests that gut microbiota alterations are related to development and phenotypes of many neuropsychiatric diseases. Here, we evaluated the fecal microbiota and its clinical correlates in patients with hereditary transthyretin amyloidosis (ATTRv) and polyneuropathy. Fecal microbiota from 38 ATTRv patients and 39 age-matched controls was analyzed by sequencing 16S V3-V4 ribosomal RNA, and its relationships with clinical characteristics of polyneuropathy and cardiomyopathy were explored. The familial amyloidotic polyneuropathy stage was stage I, II, and III in 13, 18, and 7 patients...

Transthyretin (TTR) is a tetrameric homologous protein that can dissociate into monomers. Misfolding and aggregation of TTR can lead to amyloid transthyretin amyloidosis (ATTR), which can cause many diseases (e.g., senile systemic amyloidosis, familial amyloid cardiomyopathy, and familial amyloid polyneuropathy). Despite growing evidence indicating that small oligomers play a critical role in regulating cytotoxicity, the structures of these oligomeric intermediates and their conformational transformations are still unclear, impeding our understanding of neurodegenerative mechanisms and the development of therapeutics targeting early aggregation species...

Although amyloid material in the heart is not infrequently encountered at autopsy it may on occasion be difficult to determine the significance in terms of possible contributions to the terminal mechanisms of death. A review was undertaken of the literature and of autopsy cases at Forensic Science SA over a 20-year-period (2003-2022) for all cases where significant amyloid material had been encountered on microscopy of the heart. Sixteen cases were found consisting of 11 cases where cardiac amyloid was involved in the lethal episode, and five where it was considered an incidental feature...

IMPORTANCE: Cardiopulmonary exercise testing (CPET) has an established role in the assessment of patients with heart failure. However, data are lacking in patients with transthyretin (ATTR) amyloidosis. OBJECTIVE: To use CPET to characterize the spectrum of functional phenotypes in patients with ATTR amyloidosis and assess their association with the cardiac amyloid burden as well as the association between CPET parameters and prognosis. DESIGN, SETTING AND PARTICIPANTS: This single-center study evaluated patients diagnosed with ATTR amyloidosis from May 2019 to September 2022 who underwent CPET at the National Amyloidosis Centre...

IMPORTANCE: Systemic amyloidosis from transthyretin (ATTR) protein is the most common type of amyloidosis that causes cardiomyopathy. OBSERVATIONS: Transthyretin (TTR) protein transports thyroxine (thyroid hormone) and retinol (vitamin A) and is synthesized predominantly by the liver. When the TTR protein misfolds, it can form amyloid fibrils that deposit in the heart causing heart failure, heart conduction block, or arrhythmia such as atrial fibrillation. The biological processes by which amyloid fibrils form are incompletely understood but are associated with aging and, in some patients, affected by inherited variants in the TTR genetic sequence...

AIMS: To evaluate the effect of long-term tafamidis treatment on health-related quality of life (HRQoL) in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) enrolled in the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) and long-term extension (LTE) study. METHODS AND RESULTS: We examined change from baseline in Kansas City Cardiomyopathy Questionnaire overall summary (KCCQ-OS) and clinical summary (KCCQ-CS) scores in patients who received tafamidis meglumine 80 mg for 30 months in ATTR-ACT and tafamidis (meglumine 80 mg or bioequivalent free acid 61 mg) for 30 months in the LTE study, and in patients who received placebo for 30 months in ATTR-ACT and tafamidis for 30 months in the LTE study...

Eplontersen (Wainua™) is a ligand-conjugated antisense oligonucleotide directed to TTR, which is being developed by Ionis Pharmaceuticals and AstraZeneca for the treatment of TTR-mediated amyloidosis (ATTR). Eplontersen, which is targeted to the liver by a ligand containing three N-acetyl galactosamine residues, binds to wild-type and variant TTR mRNA, thus reducing the levels of circulating TTR protein and amyloid deposition. Subcutaneous eplontersen reduced serum TTR levels, inhibited neuropathy progression and improved health-related quality of life in patients with polyneuropathy of hereditary ATTR (ATTRv-PN; v for variant) in a phase III trial...

Transthyretin amyloidosis (ATTR) is a condition defined by accumulation of insoluble transthyretin amyloid deposits in multiple organs, especially in the peripheral nerve and heart muscle. ATTR may result from transthyretin mutations (variant ATTR or ATTRv) or may occur with normal transthyretin genotype (wild type ATTR or ATTRwt). ATTRwt was previously known as "senile amyloidosis" and causes cardiomyopathy which may lead to heart failure with a preserved ejection fraction, affecting predominantly elderly men...

Background and Objectives: Hereditary transthyretin amyloidosis (ATTRv) is a rare disease caused by pathogenic variants in the transthyretin ( TTR ) gene. More than 140 different disease-causing variants in TTR have been reported. Only a few individuals with a rare TTR variant, c.302C>T, p.(Ala101Val) (historically known as p.(Ala81Val)), primarily associated with cardiac ATTRv, have been described. Therefore, our aim was to analyze the clinical characteristics of individuals with the identified c.302C>T TTR variant at our center...

BACKGROUND: The echocardiographic determination of cardiac causes of stroke focuses on the presence of left ventricular thrombus, valvular vegetations, and patent foramen ovale. Transoesophageal echocardiogram (TEE) is indicated when the transthoracic echocardiogram (TTE) is inconclusive or when there is clinical suspicion of cardiac causes that may have been missed by TTE. The presence of severe diastolic dysfunction on TTE in the absence of any other cardiac abnormality or cardiac history is not usually considered a clue to the cause of stroke...

BACKGROUND: Cardiac amyloidosis is increasingly recognized as a significant contributor to cardiovascular morbidity and mortality. With the emergence of novel therapies, there is a growing interest in prognostication of patients with cardiac amyloidosis using cardiac magnetic resonance imaging (CMR). In this systematic review and meta-analysis, we aimed to examine the prognostic significance of myocardial native T1 and T2, and extracellular volume (ECV). METHODS: Observational cohort studies or single arms of clinical trials were eligible...

There has been an exponential increase in the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CA). In response, the Midlands Amyloidosis Service was launched with the aim of providing patients with a timely diagnosis, remote expertise from the National Amyloidosis Centre and access to emerging transthyretin (TTR)-directed therapies. This was a descriptive study of a pilot hub-and-spoke model of delivering specialist amyloidosis care. Patients with suspected amyloidosis were referred from the wider Midlands region, and seen in a consultant-led multidisciplinary clinic...

BACKGROUND: Transthyretin amyloidosis (ATTR) is a significant cause of cardiomyopathy and other morbidities in the elderly and Black Americans. ATTR can be treated with new disease-modifying therapies, but large shortfalls exist in its diagnosis. The objective of this study was to test whether TTR amyloid can be detected and imaged in the conjunctiva using a novel small-molecule fluorescent ocular tracer, with the implication that ATTR might be diagnosable by a simple eye examination...

OBJECTIVES: To identify and describe the profile of potential transthyretin cardiac amyloidosis (ATTR-CM) cases in the Brazilian public health system (SUS), using a predictive machine learning (ML) model. METHODS: This was a retrospective descriptive database study that aimed to estimate the frequency of potential ATTR-CM cases in the Brazilian public health system using a supervised ML model, from January 2015 to December 2021. To build the model, a list of ICD-10 codes and procedures potentially related with ATTR-CM was created based on literature review and validated by experts...