Search

Aims: Transthyretin amyloid cardiomyopathy (ATTR‐CM) is an increasingly recognized cause of heart failure. A total of 3–4% of individuals of African descent carry a TTR gene mutation encoding the p.(V142I) variant, a powerful risk factor for development of variant ATTR‐CM (ATTRv‐CM); this equates to 1.6 million carriers in the United States. We undertook deep phenotyping of p.(V142I)‐ATTRv‐CM and comparison with wild‐type ATTR‐CM (ATTRwt‐CM). Methods and results: A retrospective study of 413 patients with p.(V142I) ATTRv‐CM who attended the UK National Amyloidosis Centre (NAC) was conducted. Patients underwent evaluation at time of diagnosis, including clinical, echocardiography, and biomarker analysis; a subgroup had cardiac magnetic resonance (CMR) imaging. A total of 413 patients with ATTRwt‐CM, matched for independent predictors of prognosis (age, NAC Stage, decade of first presentation), were used as a comparator group. At time of diagnosis, patients with ATTRv‐CM had significant functional impairment by New York Heart Association classification (NHYA class ≥ III; 38%) and 6‐min walk test distance (median 276 m). Median 5‐year survival in ATTRv‐CM patients was 31 versus 59 months in matched patients with ATTRwt‐CM (p < 0.001). Patients with ATTRv‐CM had significant impairment of functional parameters by echocardiography including biventricular impairment, high burden of regurgitant valvular disease and low cardiac output. Multivariable analysis revealed the prognostic importance of right ventricular dysfunction. CMR and histological analysis revealed myocyte atrophy and widespread myocardial infiltration in ATTRv‐CM. Conclusion: p.(V142I)‐ATTRv‐CM has an aggressive phenotype characterized by myocyte loss and widespread myocardial infiltration which may account for frequent biventricular failure and poor prognosis in this ATTR‐CM genotypic subgroup. [ABSTRACT FROM AUTHOR]

Transthyretin cardiac amyloidosis (ATTR-CA) represents an inexorably progressive and fatal cardiomyopathy. Increased understanding of the underlying pathogenesis responsible for the misfolding of transthyretin and the subsequent accumulation of amyloid fibrils within the myocardium has led to the development of several disease-modifying therapies that act on different stages of the disease pathway. Tafamidis is the first, and to date remains the only, therapy approved for the treatment of ATTR-CA, which, alongside acoramidis, stabilizes the transthyretin tetramer, preventing disaggregation, misfolding and formation of amyloid fibrils. Gene-silencing agents, such as patisiran, vutrisian and eplontersen, and novel gene-editing therapies, such as NTLA-2001, act to reduce the hepatic synthesis of transthyretin. Anti-amyloid therapies represent another strategy in the treatment of ATTR-CA and are designed to bind amyloid fibril epitopes and stimulate macrophage-mediated removal of amyloid fibrils from the myocardium. Many of these treatments are at an early investigational stage but represent an important area of unmet clinical need and could potentially reverse disease and restore cardiac functions even in patients with advanced disease. [ABSTRACT FROM AUTHOR]

Aims To perform evaluation of widely embraced bone scintigraphy-based non-biopsy diagnostic criteria (NBDC) for ATTR amyloid cardiomyopathy (ATTR-CM) in clinical practice, and to refine serum free light chain (sFLC) ratio cut-offs that reliably exclude monoclonal gammopathy (MG) in chronic kidney disease. Methods and results A multi-national retrospective study of 3354 patients with suspected or histologically proven cardiac amyloidosis (CA) referred to specialist centres from 2015 to 2021; evaluations included radionuclide bone scintigraphy, serum and urine immunofixation, sFLC assay, eGFR measurement and echocardiography. Seventy-nine percent (1636/2080) of patients with Perugini grade 2 or 3 radionuclide scans fulfilled NBDC for ATTR-CM through absence of a serum or urine monoclonal protein on immunofixation together with a sFLC ratio falling within revised cut-offs incorporating eGFR; 403 of these patients had amyloid on biopsy, all of which were ATTR type, and their survival was comparable to non-biopsied ATTR-CM patients (p = 0.10). Grade 0 radionuclide scans were present in 1091 patients, of whom 284 (26%) had CA, confirmed as AL type (AL-CA) in 276 (97%) and as ATTR-CM in only one case with an extremely rare TTR variant. Among 183 patients with grade 1 radionuclide scans, 122 had MG of whom 106 (87%) had AL-CA; 60/61 (98%) without MG had ATTR-CM. Conclusion The NBDC for ATTR-CM are highly specific [97% (95% CI 0.91-0.99)] in clinical setting, and diagnostic performance was further refined here using new cut-offs for sFLC ratio in patients with CKD. A grade 0 radionuclide scan all but excludes ATTR-CM but occurs in most patients with AL-CA. Grade 1 scans in patients with CA and no MG are strongly suggestive of early ATTR-type, but require urgent histologic corroboration. [ABSTRACT FROM AUTHOR]

Aims: Transthyretin amyloid cardiomyopathy (ATTR‐CM) is often assumed to be associated with wild‐type TTR genotype (ATTRwt) in elderly patients (aged ≥70), some of whom are not offered genetic testing. We sought to estimate the prevalence, clinical characteristics and prognostic implications of transthyretin (TTR) variants among elderly patients diagnosed with ATTR‐CM. Methods and results: Data from consecutive patients over 70 years of age diagnosed with ATTR‐CM at the UK National Amyloidosis Centre between January 2010 and August 2022 were retrospectively evaluated. All patients underwent clinical evaluation, biochemical tests, echocardiography and TTR genotyping. The study outcome was all‐cause mortality. The study population consisted of 2029 patients with ATTR‐CM (median age 79 years at diagnosis, 13.5% females, 80.4% Caucasian). Variant ATTR‐CM (ATTRv‐CM) was diagnosed in 20.7% (n = 421) of the study population of whom 327 (77.7%) carried V122I, 47 (11.2%) T60A, 16 (3.8%) V30M and 31 (7.3%) other pathogenic TTR variants. During a median (range) follow‐up of 29 (12–48) months, ATTRv‐CM was associated with increased all‐cause mortality compared to ATTRwt‐CM, with the poorest survival observed in V122I‐associated ATTRv‐CM (p < 0.001). Univariable and multivariable logistic regression analyses in those with ATTR‐CM showed younger age at diagnosis (odds ratio [OR] 0.85 per year, p < 0.001), female sex (OR 2.73, p < 0.001), Afro‐Caribbean ethnicity (OR 65.5, p < 0.001), atrial fibrillation (OR 0.65, p = 0.015), ischaemic heart disease (OR 0.54, p = 0.007), peripheral polyneuropathy (OR 5.70, p < 0.001) and orthostatic hypotension (OR 6.29, p < 0.001) to be independently associated with ATTRv‐CM. Conclusion: Up to 20.7% of elderly patients with ATTR‐CM have a pathogenic TTR variant. These findings support routine sequencing of the TTR gene in all patients with ATTR‐CM regardless of age. [ABSTRACT FROM AUTHOR]

Transthyretin (TTR) is a tetrameric protein synthesized primarily by the liver. TTR can misfold into pathogenic ATTR amyloid fibrils that deposit in the nerves and heart, causing a progressive and debilitating polyneuropathy (PN) and life-threatening cardiomyopathy (CM). Therapeutic strategies, which are aimed at reducing ongoing ATTR amyloid fibrillogenesis, include stabilization of the circulating TTR tetramer or reduction of TTR synthesis. Small interfering RNA (siRNA) or antisense oligonucleotide (ASO) drugs are highly effective at disrupting the complementary mRNA and inhibiting TTR synthesis. Since their development, patisiran (siRNA), vutrisiran (siRNA) and inotersen (ASO) have all been licensed for treatment of ATTR-PN, and early data suggest these drugs may have efficacy in treating ATTR-CM. An ongoing phase 3 clinical trial will evaluate the efficacy of eplontersen (ASO) in the treatment of both ATTR-PN and ATTR-CM, and a recent phase 1 trial demonstrated the safety of novel in vivo CRISPR-Cas9 gene-editing therapy in patients with ATTR amyloidosis. Recent results from trials of gene silencer and gene-editing therapies suggest these novel therapeutic agents have the potential to substantially alter the landscape of treatment for ATTR amyloidosis. Their success has already changed the perception of ATTR amyloidosis from a universally progressive and fatal disease to one that is treatable through availability of highly specific and effective disease-modifying therapies. However, important questions remain including long-term safety of these drugs, potential for off-target gene editing, and how best to monitor the cardiac response to treatment.Kindly check and confirm the processed running title.This is correct [ABSTRACT FROM AUTHOR]

Transthyretin (TTR) is a tetrameric protein, synthesized primarily by the liver, that acts as a physiological transport protein for retinol and thyroxine. TTR can misfold into pathogenic amyloid fibrils that deposit in the heart and nerves, causing a life-threatening transthyretin amyloidosis cardiomyopathy (ATTR-CM), and a progressive and debilitating polyneuropathy (ATTR-PN). Recent therapeutic advances have resulted in the development of drugs that reduce TTR production. Patisiran is a small interfering RNA that disrupts the complimentary mRNA and inhibits TTR synthesis, and is the first gene-silencing medication licensed for the treatment of ATTR amyloidosis. After encouraging results following the use of patisiran for the treatment of patients with ATTR-PN, there has been increasing interest in the use of patisiran for the treatment of ATTR-CM. Various studies have demonstrated improvements across a wide range of cardiac biomarkers following treatment with patisiran, and have changed the perception of ATTR-CM from being thought of as a terminal disease process, to now being regarded as a treatable disease. These successes represent a huge milestone and have the potential to revolutionize the landscape of treatment for ATTR-CM. However, the long- term safety of patisiran and how best to monitor cardiac response to treatment remain to be determined. [ABSTRACT FROM AUTHOR]

Aims: Transthyretin amyloid cardiomyopathy (ATTR‐CM) is predominantly diagnosed in men. The few available studies suggest affected women have a more favourable cardiac phenotype. We aimed to characterize sex differences among consecutive patients with non‐hereditary and two prevalent forms of hereditary (h)ATTR‐CM diagnosed over a 20‐year period. Methods and results: Analysis of deep phenotyping at presentation, changes on serial echocardiography and overall prognosis were evaluated. In total, 1732 consecutive patients were studied, comprising: 1095 with wild‐type (wt)ATTR‐CM; 206 with T60A‐hATTR‐CM; and 431 with V122I‐hATTR‐CM. Female prevalence was greater in T60A‐hATTR‐CM (29.6%) and V122I‐hATTR‐CM (27.8%) compared to wtATTR‐CM (6%). At presentation, females were 3.3 years older than males (wtATTR‐CM: 81.9 vs. 77.8 years; T60A‐hATTR‐CM: 68.7 vs. 65.1 years; V122I‐hATTR‐CM: 77.1 vs. 74.9 years). Body size significantly influenced measures of disease severity; when indexed, overall structural and functional phenotype was similar between sexes, the few significant differences suggested a mildly worse phenotype in females. No significant differences were observed in both disease progression on serial echocardiography and mortality across the overall population (p = 0.459) and when divided by genotype (wtATTR‐CM: p = 0.730; T60A‐hATTR‐CM: p = 0.161; V122I‐hATTR‐CM: p = 0.056). Conclusion: This study of a well‐characterized large cohort of ATTR‐CM patients did not demonstrate overall differences between sexes in either clinical phenotype, when indexed, or with respect to disease progression and prognosis. Non‐indexed wall thickness measurements may have contributed to both under‐representation and delays in diagnosis for affected females and highlights the potential role of utilizing indexed echocardiographic parameters for a more accurate assessment of patients at diagnosis and for disease prognostication. [ABSTRACT FROM AUTHOR]

Background: Diagnostic and therapeutic advances have led to much greater awareness of transthyretin cardiac amyloidosis (ATTR-CA). We aimed to characterize changes in the clinical phenotype of patients diagnosed with ATTR-CA over the past 20 years.Methods: This is a retrospective observational cohort study of all patients referred to the National Amyloidosis Centre (2002-2021) in whom ATTR-CA was a differential diagnosis.Results: We identified 2995 patients referred with suspected ATTR-CA, of whom 1967 had a diagnosis of ATTR-CA confirmed. Analysis by 5-year periods revealed an incremental increase in referrals, with higher proportions of patients having been referred after bone scintigraphy and cardiac magnetic resonance imaging (2% versus 34% versus 51% versus 55%, chi-square P<0.001). This was accompanied by a greater number of ATTR-CA diagnoses, predominantly of the wild-type nonhereditary form, which is now the most commonly diagnosed form of ATTR-CA (0% versus 54% versus 67% versus 66%, chi-square P<0.001). Over time, the median duration of associated symptoms before diagnosis fell from 36 months between 2002 and 2006 to 12 months between 2017 and 2021 (Mann-Whitney P<0.001), and a greater proportion of patients had early-stage disease at diagnosis across the 5-year periods (National Amyloidosis Centre stage 1: 34% versus 42% versus 44% versus 53%, chi-square P<0.001). This was associated with more favorable echocardiographic parameters of structure and function, including lesser interventricular septal thickness (18.0±3.8 mm versus 17.2±2.6 mm versus 16.9±2.3 mm versus 16.6±2.4 mm, P=0.01) and higher left ventricular ejection fraction (46.0%±8.9% versus 46.8%±11.0% versus 47.8%±11.0% versus 49.5%±11.1%, P<0.001). Mortality decreased progressively during the study period (2007-2011 versus 2012-2016: hazard ratio, 1.57 [95% CI, 1.31-1.89], P<0.001; and 2012-2016 versus 2017-2021: hazard ratio, 1.89 [95% CI, 1.55-2.30], P<0.001). The proportion of patients enrolled into clinical trials and prescribed disease-modifying therapy increased over the 20-year period, but even when censoring at the trial or medication start date, year of diagnosis remained a significant predictor of mortality (2012-2016 versus 2017-2021: hazard ratio, 1.05 [95% CI, 1.03-1.07], P<0.001).Conclusions: There has been a substantial increase in ATTR-CA diagnoses, with more patients being referred after local advanced cardiac imaging. Patients are now more often diagnosed at an earlier stage of the disease, with substantially lower mortality. These changes may have important implications for initiation and outcome of therapy and urgently need to be factored into clinical trial design. [ABSTRACT FROM AUTHOR]