Complete responses in AL amyloidosis are unequal: the impact of free light chain mass spectrometry in AL amyloidosis.

ABSTRACT: Amyloidogenic serum free light chains (sFLCs) drive disease progression in AL amyloidosis. Matrix-assisted laser desorption/ionization time of flight mass spectrometry-based FLC assay (FLC-MS) has greater sensitivity than conventional sFLC assays allowing for the detection of serological residual disease. We report the utility of FLC-MS in a large series of patients with AL amyloidosis assessing the impact of FLC-MS negativity after treatment on overall survival (OS) and organ response rates. Serum samples were analyzed using FLC-MS at diagnosis and at 6 and 12 months after treatment. The impact of FLC-MS negativity over standard hematologic responses on survival and organ response was assessed. A total of 487 patients were included; 290 (59%) and 349 (71.5%) had cardiac and renal involvement, respectively. There was 100% concordance between the light chain (LC) fibril type and LC isotype identified by FLC-MS. At 6 and 12 months, 81 (16.6%) and 101 (20.7%) were FLC-MS negative. Of those achieving a conventional hematologic complete response (CR) at 6 and 12 months, 45 (27.7%) and 64 (39%) were FLC-MS negative. At 12 months, median OS for CR + FLC-MS negative was not reached vs 108 months in CR + FLC-MS positive (P = .024). At 12 months, 70% of patients with FLC-MS negativity (vs 50% FLC-MS positive) achieved a cardiac response (P = .015). In a multivariate analysis, FLC-MS negativity at 12 months was an independent predictor of better outcomes. FLC-MS can detect persistent monoclonal light chains in a significant proportion of patients in a conventional hematologic CR. FLC-MS assessment promises to be a new standard for response assessment in AL amyloidosis.

Response rates to second-line treatment with daratumumab bortezomib dexamethasone (DVD) in relapsed/refractory light chain amyloidosis (AL) after initial Bortezomib-based regime.

Bortezomib is regularly used as frontline therapy for systemic AL amyloidosis. We assess the efficacy of second-line daratumumab-bortezomib-dexamethasone (DVD) in AL amyloidosis in bortezomib-exposed patients. A total of 116 patients treated with second-line DVD were identified from a prospective observational study of newly diagnosed AL amyloidosis (ALchemy). DVD was initiated in both the relapsed setting or where there was an inadequate response defined as very good partial response (VGPR) or VGPR with organ progression/lack of organ improvement. A complete response (CR)/VGPR to second-line DVD was achieved in 81 (69.8%) patients. A CR/VGPR was achieved in 67 (79.7%) in those who achieved a VGPR/CR to first line versus 14/32 (43.8%) in those who did not. Where DVD was initiated due to an inadequate response to first line (vs. at relapse), the median event-free survival (EFS) was 18 vs. 34 months (p = 0.002). If a CR/VGPR was achieved to DVD, the 2-year EFS was still lower in those with prior inadequate response 54% vs. 66% (p = 0.062). DVD is an efficacious second-line treatment in systemic AL amyloidosis in a bortezomib-exposed population. However, the response to DVD is poorer in those with an inadequate response to first-line bortezomib.

Native myocardial T1 and right ventricular size by CMR predict outcome in systemic sclerosis-associated pulmonary hypertension.

OBJECTIVES: Measures of right heart size and function are prognostic in systemic sclerosis-associated pulmonary hypertension (SSc-PH), but the importance of myocardial tissue characterisation remains unclear. We aimed to investigate the predictive potential and interaction of cardiovascular magnetic resonance (CMR) myocardial tissue characterisation and right heart size and function in SSc-PH. METHODS: A retrospective, single-centre, observational study of 148 SSc-PH patients confirmed by right heart catheterization who underwent clinically-indicated CMR including native myocardial T1 and T2 mapping from 2016 to 2023 was performed. RESULTS: Sixty-six (45%) patients died during follow-up (median 3.5 years, range 0.1-7.3). Patients who died were older (65 vs 60 years, p= 0.035) with more dilated (RVEDVi and RVESVi, p< 0.001), hypertrophied (RVMi, p= 0.013) and impaired (RVEF, p< 0.001) right ventricles, more dilated right atria (RAi, p= 0.043) and higher native myocardial T1 (p< 0.001).After adjustment for age, RVESVi (p = 0.0023) and native T1 (p = 0.0024) were independent predictors of all-cause mortality. Both RVESVi and native T1 remained independently predictive after adjusting for age and PH subtype (RVESVi p < 0.001, T1 p = 0.0056). Optimal prognostic thresholds for RVESVi and native T1 were ≤38 mL/m2 and ≤1119 ms, respectively (p < 0.001). Patients with RVESVi ≤ 38 mL/m2 and native T1 ≤ 1119 ms had significantly better outcomes than all other combinations (p < 0.001). Furthermore, patients with RVESVi > 38mL/m2 and native T1 ≤ 1119 ms had significantly better survival than patients with RVESVi > 38mL/m2 and native T1 > 1119ms (p = 0.017). CONCLUSION: We identified prognostically relevant CMR metrics and thresholds for patients with SSc-PH. Assessing myocardial tissue characterisation alongside RV function confers added value in SSc-PH and may represent an additional treatment target.

Conventional heart failure therapy in cardiac ATTR amyloidosis.

AIMS: The aims of this study were to assess prescription patterns, dosages, discontinuation rates, and association with prognosis of conventional heart failure medications in patients with transthyretin cardiac amyloidosis (ATTR-CA). METHODS AND RESULTS: A retrospective analysis of all consecutive patients diagnosed with ATTR-CA at the National Amyloidosis Centre between 2000 and 2022 identified 2371 patients with ATTR-CA. Prescription of heart failure medications was greater among patients with a more severe cardiac phenotype, comprising beta-blockers in 55.4%, angiotensin-converting enzyme inhibitors (ACEis)/angiotensin II receptor blockers (ARBs) in 57.4%, and mineralocorticoid receptor antagonists (MRAs) in 39.0% of cases. During a median follow-up of 27.8 months (interquartile range 10.6-51.3), 21.7% had beta-blockers discontinued, and 32.9% had ACEi/ARBs discontinued. In contrast, only 7.5% had MRAs discontinued. A propensity score-matched analysis demonstrated that treatment with MRAs was independently associated with a reduced risk of mortality in the overall population [hazard ratio (HR) 0.77 (95% confidence interval (CI) 0.66-0.89), P < .001] and in a pre-specified subgroup of patients with a left ventricular ejection fraction (LVEF) >40% [HR 0.75 (95% CI 0.63-0.90), P = .002]; and treatment with low-dose beta-blockers was independently associated with a reduced risk of mortality in a pre-specified subgroup of patients with a LVEF ≤40% [HR 0.61 (95% CI 0.45-0.83), P = .002]. No convincing differences were found for treatment with ACEi/ARBs. CONCLUSION: Conventional heart failure medications are currently not widely prescribed in ATTR-CA, and those that received medication had more severe cardiac disease. Beta-blockers and ACEi/ARBs were often discontinued, but low-dose beta-blockers were associated with reduced risk of mortality in patients with a LVEF ≤40%. In contrast, MRAs were rarely discontinued and were associated with reduced risk of mortality in the overall population; but these findings require confirmation in prospective randomized controlled trials.

Tc-99m labelled bone scintigraphy in suspected cardiac amyloidosis.

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.

Impact of Earlier Diagnosis in Cardiac ATTR Amyloidosis Over the Course of 20 Years.

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.

Characteristics and natural history of early-stage cardiac transthyretin amyloidosis.

AIMS: Transthyretin amyloid cardiomyopathy (ATTR-CM) is increasingly diagnosed at an early stage of the disease natural history, defined as National Amyloidosis Centre (NAC) ATTR Stage I. The natural history of early-stage ATTR-CM remains poorly characterized. METHODS AND RESULTS: A retrospective multi-centre observational study of 879 patients with ATTR-CM, either wild-type TTR genotype or carrying the p.V142I TTR variant, and NAC ATTR Stage I biomarkers at the time of diagnosis who did not receive disease-modifying therapy for amyloidosis. Disease characteristics at diagnosis that were independently associated with mortality by Cox regression analysis were N-terminal pro-B-type natriuretic peptide (NT-proBNP), TTR genotype, and troponin T. Patients were categorized into NAC ATTR Stage Ia, defined as a furosemide equivalent diuretic requirement of <0.75 mg/kg and an NT-proBNP ≤500 ng/L or ≤1000 ng/L in the presence of atrial fibrillation, and NAC ATTR Stage Ib comprising all remaining Stage I patients. Median estimated survival among the 88% NAC ATTR Stage Ib patients was 75 (95% CI 57-93) months compared with >100 months in the 12% with Stage Ia disease [hazard ratio for death 5.06 (95% confidence interval 1.23-20.87); P = 0.025] despite significant cardiovascular morbidity at the time of diagnosis which increased during follow-up, including among patients diagnosed in NAC ATTR Stage Ia. Estimated survival among UK NAC ATTR Stage Ia patients was comparable to UK general population controls (P = 0.297). CONCLUSION: Patients with NAC ATTR Stage I ATTR-CM can be further stratified according to NT-proBNP concentration and diuretic requirement at diagnosis. Patients with Stage Ia ATTR-CM have significant cardiovascular morbidity despite good short- and mid-term survival.

Longitudinal strain is an independent predictor of survival and response to therapy in patients with systemic AL amyloidosis.

AIMS: Cardiac involvement, a major determinant of prognosis in AL (light-chain immunoglobulin) amyloidosis, is characterized by an impairment of longitudinal strain (LS%). We sought to evaluate the utility of LS% in a prospectively observed series of patients. METHODS AND RESULTS: A total of 915 serial newly diagnosed AL patients with comprehensive baseline assessments, inclusive of echocardiography, were included. A total of 628/915 (68.6%) patients had cardiac involvement. The LS% worsened with advancing cardiac stage with mean -21.1%, -17.1%, -12.9%, and -12.1% for stages I, II, IIIa, and IIIb, respectively (P < 0.0001). There was a highly significant worsening of overall survival (OS) with worsening LS% quartile: LS% ≤-16.2%: 80 months, -16.1% to -12.2%: 36 [95% confidence interval (CI) 20.9-51.1] months, -12.1% to -9.1%: 22 (95% CI 9.1-34.9) months, and ≥-9.0%: 5 (95% CI 3.2-6.8) months (P < 0.0001). Improvement in LS% was seen at 12 months in patients achieving a haematological complete response (CR) (median improvement from -13.8% to -14.9% in those with CR and difference between involved and uninvolved light chain <10 mg/L). Strain improvement was associated with improved OS (median not reached at 53 months vs. 72 months in patients without strain improvement, P = 0.007). Patients achieving an LS% improvement and a standard N-terminal pro-brain natriuretic peptide-based cardiac response survived longer than those achieving a biomarker-based cardiac response alone (P < 0.0001). CONCLUSION: Baseline LS% is a functional marker that correlates with worsening cardiac involvement and is predictive of survival. Baseline LS% and an absolute improvement in LS% are useful additional measures of prognosis and response to therapy in cardiac AL amyloidosis, respectively.

Cardiovascular magnetic resonance in light-chain amyloidosis to guide treatment.

AIMS: To assess the ability of cardiovascular magnetic resonance (CMR) to (i) measure changes in response to chemotherapy; (ii) assess the correlation between haematological response and changes in extracellular volume (ECV); and (iii) assess the association between changes in ECV and prognosis over and above existing predictors. METHODS AND RESULTS: In total, 176 patients with cardiac AL amyloidosis were assessed using serial N-terminal pro-B-type natriuretic peptide (NT-proBNP), echocardiography, free light chains and CMR with T1 and ECV mapping at diagnosis and subsequently 6, 12, and 24 months after starting chemotherapy. Haematological response was graded as complete response (CR), very good partial response (VGPR), partial response (PR), or no response (NR). CMR response was graded by changes in ECV as progression (≥0.05 increase), stable (<0.05 change), or regression (≥0.05 decrease). At 6 months, CMR regression was observed in 3% (all CR/VGPR) and CMR progression in 32% (61% in PR/NR; 39% CR/VGPR). After 1 year, 22% had regression (all CR/VGPR), and 22% had progression (63% in PR/NR; 37% CR/VGPR). At 2 years, 38% had regression (all CR/VGPR), and 14% had progression (80% in PR/NR; 20% CR/VGPR). Thirty-six (25%) patients died during follow-up (40 ± 15 months); CMR response at 6 months predicted death (progression hazard ratio 3.82; 95% confidence interval 1.95-7.49; P < 0.001) and remained prognostic after adjusting for haematological response, NT-proBNP and longitudinal strain (P < 0.01). CONCLUSIONS: Cardiac amyloid deposits frequently regress following chemotherapy, but only in patients who achieve CR or VGPR. Changes in ECV predict outcome after adjusting for known predictors.

Viral Myocarditis and Dilated Cardiomyopathy as a Consequence-Changing Insights from Advanced Imaging.

Advancements in quantitative cardiac magnetic resonance (CMR) have revolutionized the diagnosis and management of viral myocarditis. With the addition of T1 and T2 mapping parameters in the updated Lake Louise Criteria, CMR can diagnose myocarditis with superior diagnostic accuracy compared with endomyocardial biopsy, especially in stable patients. Additionally, the unique value of CMR tissue characterization continues to improve the diagnosis and risk stratification of myocarditis. This review will discuss new and ongoing developments in cardiovascular imaging and its application to noninvasive diagnosis, prognostication, and management of viral myocarditis and its complications.

Haematologic responses and survival do not significantly decrease with subsequent lines of therapy in systemic immunoglobulin light chain amyloidosis: results from an analysis of real-world longitudinal data.

Systemic immunoglobulin light chain amyloidosis (AL) is an incurable disorder, and the natural history is incompletely understood. In this study, we describe its natural history based on an analysis of real-world longitudinal data. All patients seen at the National Amyloidosis Centre, UK, between February 2010 and August 2019 and treated with up-front bortezomib are included. In all, 1 276 patients received the first-line treatment; 259, 85, and 32 patients received second, third, and fourth treatment lines, respectively. Among patients requiring further treatment after the first line, 77·2% started the second line within two years of the first line; 50·5%, 50·6%, 40·1% and 40·6% of patients had achieved at least very good partial response after the first, second, third and fourth treatment lines. Median overall survival (OS) from first, second, third and fourth lines was 45 months, 56 months, 37 months and not reached, respectively (P = 0·109). In summary, although relapses occur in AL amyloidosis, the outcomes and responses do not worsen with each subsequent relapse, making it attractive to design therapeutics with curative intent.

Urinary retinol binding protein predicts renal outcome in systemic immunoglobulin light-chain (AL) amyloidosis.

Renal risk stratification in systemic immunoglobulin light-chain (AL) amyloidosis is according to estimated glomerular filtration rate (eGFR) and urinary protein creatinine ratio (uPCR), the latter attributed to glomerular dysfunction, with proximal tubular dysfunction (PTD) little studied. Urinary retinol binding protein 4 (uRBP), a low molecular weight tubular protein and highly sensitive marker of PTD, was prospectively measured in 285 newly diagnosed, untreated patients with systemic AL amyloidosis between August 2017 to August 2018. At diagnosis, the uRBP/creatinine ratio (uRBPCR) correlated with serum creatinine (r = 0·618, P < 0·0001), uPCR (r = 0·422, P < 0·0001) as well as both fractional excretion of phosphate and urate (r = 0·563, P < 0·0001). Log uRBPCR at diagnosis was a strong independent predictor of end-stage renal disease {hazard ratio [HR] 2·65, [95% confidence interval (CI) 1·06-6·64]; P = 0·038}, particularly in patients with an eGFR >30 ml/min/1.73 m2 [HR 4·11, (95% CI 1·45-11·65); P = 0·008] and those who failed to achieve a deep haematological response to chemotherapy within 3 months of diagnosis [HR 6·72, (95% CI 1·83-24·74); P = 0·004], and also predicted renal progression [HR 1·91, (95% CI 1·18-3·07); P = 0·008]. Elevated uRBPCR indicates PTD and predicts renal outcomes independently of eGFR, uPCR and clonal response in systemic AL amyloidosis. The role of uRBPCR as a novel prognostic biomarker merits further study, particularly in monoclonal gammopathies of renal significance.

A simple echocardiographic score to rule out cardiac amyloidosis.

BACKGROUND: Early diagnosis of cardiac amyloidosis (CA) is warranted to initiate specific treatment and improve outcome. The amyloid light chain (AL) and inferior wall thickness (IWT) scores have been proposed to assess patients referred by haematologists or with unexplained left ventricular (LV) hypertrophy, respectively. These scores are composed of 4 or 5 variables, respectively, including strain data. METHODS: Based on 2 variables common to the AL and IWT scores, we defined a simple score named AMYLoidosis Index (AMYLI) as the product of relative wall thickness (RWT) and E/e' ratio, and assessed its diagnostic performance. RESULTS: In the original cohort (n = 251), CA was ultimately diagnosed in 111 patients (44%). The 2.22 value was selected as rule-out cut-off (negative likelihood ratio [LR-] 0.0). In the haematology subset, AL CA was diagnosed in 32 patients (48%), with 2.36 as rule-out cut-off (LR- 0.0). In the hypertrophy subset, ATTR CA was diagnosed in 79 patients (43%), with 2.22 as the best rule-out cut-off (LR- 0.0). In the validation cohort (n = 691), the same cut-offs proved effective: indeed, there were no patients with CA in the whole population or in the haematology or hypertrophy subsets scoring < 2.22, <2.36 or < 2.22, respectively. CONCLUSIONS: The AMYLI score (RWT*E/e') may have a role as an initial screening tool for CA. A < 2.22 value excludes the diagnosis in patients undergoing a diagnostic screening for CA, while a < 2.36 and a < 2.22 value may be better considered in the subsets with suspected cardiac AL amyloidosis or unexplained hypertrophy, respectively.

Echocardiographic phenotype and prognosis in transthyretin cardiac amyloidosis.

AIMS: Transthyretin amyloidosis cardiomyopathy (ATTR-CM) is an increasingly recognized cause of heart failure. We sought to characterize the structural and functional echocardiographic phenotype across the spectrum of wild-type (wtATTR-CM) and hereditary (hATTR-CM) transthyretin cardiomyopathy and the echocardiographic features predicting prognosis. METHODS AND RESULTS: We studied 1240 patients with ATTR-CM who underwent prospective protocolized evaluations comprising full echocardiographic assessment and survival between 2000 and 2019, comprising 766 with wtATTR-CM and 474 with hATTR-CM, of whom 314 had the V122I variant and 127 the T60A variant. At diagnosis, patients with V122I-hATTR-CM had the most severe degree of systolic and diastolic dysfunction across all echocardiographic parameters and patients with T60AhATTR-CM the least; patients with wtATTR-CM had intermediate features. Stroke volume index, right atrial area index, longitudinal strain, and E/e' were all independently associated with mortality (P < 0.05 for all). Severe aortic stenosis (AS) was also independently associated with prognosis, conferring a significantly shorter survival (median survival 22 vs. 53 months, P = 0.001). CONCLUSION: The three distinct genotypes present with varying degrees of severity. Echocardiography indicates a complex pathophysiology in which both systolic and diastolic function are independently associated with mortality. The presence of severe AS was independently associated with significantly reduced patient survival.

Natural History, Quality of Life, and Outcome in Cardiac Transthyretin Amyloidosis.

BACKGROUND: Transthyretin amyloidosis cardiomyopathy (ATTR-CM) is an increasingly recognized cause of heart failure in older individuals. We sought to characterize the natural history of ATTR-CM and compare outcomes and quality of life among patients with acquired and hereditary forms of the disease. METHODS: We studied 711 patients with wild-type ATTR-CM, 205 with hereditary ATTR-CM associated with the V1221 variant (V122I-hATTR-CM), and 118 with non-V122I-hATTR-CM at the UK National Amyloidosis Center between 2000 and 2017. Patients underwent prospective protocolized evaluations comprising assessment of cardiac parameters, functional status by 6-minute walk test, quality of life according to the Kansas City Cardiomyopathy Questionnaire, and survival. Hospital service usage pre- and postdiagnosis was established using English central health records in a subset of patients. RESULTS: There was substantial diagnostic delay, with patients using hospital services a median (interquartile range) of 17 (9-27) times during the 3 years before diagnosis, by which time quality of life was poor; diagnosis of wild-type ATTR-CM was delayed >4 years after presentation with cardiac symptoms in 42% of cases. Patients with V122I-hATTR-CM were more impaired functionally ( P<0.001) and had worse measures of cardiac disease ( P<0.001) at the time of diagnosis, a greater decline in quality of life, and poorer survival ( P<0.001) in comparison with the other subgroups. CONCLUSIONS: ATTR-CM is an inexorably progressive and eventually fatal cardiomyopathy associated with poor quality of life. Diagnosis is often delayed for many years after symptoms develop. Improved awareness and wider use of recently validated diagnostic imaging methods are urgently required for patients to benefit from recent therapeutic developments.

Use of ixazomib, lenalidomide and dexamethasone in patients with relapsed amyloid light-chain amyloidosis.

With improving outcomes in amyloid light-chain (AL) amyloidosis, there is a need to study novel agents in this setting. We report outcomes of 40 patients with relapsed AL amyloidosis treated with ixazomib + lenalidomide + dexamethasone (IRd). Haematological responses were assessed on an intention-to-treat basis at three months: complete response (CR) - 8 (20·5%), very good partial response (VGPR) - 8 (20·5%), partial response (PR) - 7 (17·9%) and no response (NR) - 16 (41·0%). One patient had missing data. Six patients subsequently improved response. Best responses were: CR - 10 (25·6%), VGPR - 8 (20·5%), PR - 7 (17·9%), NR - 14 (35·9%). Cardiac and renal organ responses occurred in 5·6% and 13·3% respectively. Median progession-free survival (PFS) was 17·0 months (95% CI 7·3-20·7 months), improving to 28·8 months (95% CI 20·6-37·0 months) in those achieving CR/VGPR. Median overall survival was 29·1 months (95% CI 24-33 months). Serious adverse events were seen in 14 (35·0%) patients inclusive of 15 admissions due to: infection (6/15, 40·0%), fluid overload (5/15, 33·3%), cardiac arrhythmia (2/15, 13·3%), renal dysfunction (1/15, 6·6%) and anaemia (1/15, 6·6%). In summary, IRd is an oral treatment option with a manageable toxicity profile leading to deep responses in 47% of patients with relapsed AL amyloidosis.

Cardiac biomarkers are prognostic in systemic light chain amyloidosis with no cardiac involvement by standard criteria.

Patients with systemic immunoglobulin light chain amyloidosis (AL) with no evidence of cardiac involvement by consensus criteria have excellent survival, but 20% will die within 5 years of diagnosis and prognostic factors remain poorly characterised. We report the outcomes of 378 prospectively followed Mayo stage I patients (N-terminal pro b-type natriuretic peptide <332 ng/L, high sensitivity cardiac troponin <55 ng/L). The median presenting N-terminal pro b-type natriuretic peptide was 161 ng/L, high sensitivity cardiac troponin 10 ng/L, creatinine 76 µmol/L and mean left ventricular septal wall thickness, 10 mm. Median follow up was 42 (1-117 months), with 71 deaths; median overall survival was not reached (78% survival at 5 years). Although no patients had cardiac involvement by echocardiogram, a proportion (n=25/90, 28%) had cardiac involvement by cardiac magnetic resonance imaging. Age, autonomic nervous system involvement, N-terminal pro b-type natriuretic peptide >152 ng/L, high sensitivity cardiac troponin >10 ng/L and cardiac involvement by magnetic resonance imaging were predictive for survival; on multivariate analysis only N-terminal pro b-type natriuretic peptide >152 ng/L (P<0.008, hazard ratio [HR] 3.180, confidence interval [CI]: 1.349-7.495) and cardiac involvement on magnetic resonance imaging (P=0.026, HR=5.360, CI: 1.219-23.574) were prognostic. At 5 years, 70% of patients with N-terminal pro b-type natriuretic peptide >152 ng/L were alive. In conclusion, N-terminal pro b-type natriuretic peptide is prognostic for survival in patients with no cardiac involvement by consensus criteria and cardiac involvement is detected by magnetic resonance imaging in such cases. This suggests that N-terminal pro b-type natriuretic peptide thresholds for cardiac involvement in AL may need to be redefined.

The value of screening biopsies in light-chain (AL) and transthyretin (ATTR) amyloidosis.

INTRODUCTION: Systemic amyloidosis is a histological diagnosis, often achieved via critical organ biopsy. Screening biopsies represent a low-risk approach to diagnosis. OBJECTIVES AND METHODS: All patients with systemic AL and ATTR amyloidosis who underwent abdominal fat aspiration (AFA) and either a bone marrow (BM) or gastrointestinal (GI) biopsy at the UK National Amyloidosis Centre (2006-2019) were identified. We sought to determine diagnostic sensitivity in relation to whole body amyloid burden, amyloid type and organ involvement. RESULTS: Diagnostic sensitivity established in 471 patients with AL (n = 321) and ATTR (n = 150) amyloidosis, respectively, was 73.2% and 27.3% for AFA (P< .001), 59.7% and 42.2% for BM (P< .001), and 74.6% and 44.6% for GI biopsy (P< .001). ATTR amyloid deposits were detected in 35.4% BMs and 33.3% of GI biopsies when AFA did not demonstrate amyloid. In AL amyloidosis, sensitivity of combined AFA and BM biopsy in AL amyloidosis was 82.9%. There was a strong association between whole body amyloid burden and sensitivity of each screening biopsy method. The diagnostic sensitivity of screening biopsies ranged from 80.0% to 90.5% for patients with a large amyloid load on 123 I-SAP scintigraphy in comparison with 53.9%-79.0% in those with no visceral amyloid visible on imaging. CONCLUSION: Performing both AFA and BM biopsy should be considered in suspected AL amyloidosis to substantially reduce the clinical risk associated with critical organ biopsy. The sensitivity of screening biopsies in ATTR amyloidosis is poor.

Analysis of the TTR gene in the investigation of amyloidosis: A 25-year single UK center experience.

Transthyretin amyloidosis (ATTR) is caused by deposition of either wild-type (ATTRwt) or variant (ATTRm) transthyretin. ATTRwt presents with restrictive cardiomyopathy, while ATTRm displays a range of organ involvement. This retrospective analysis includes all patients referred to a single UK center in the last 25 years for clinical and laboratory assessment of known or suspected amyloidosis who underwent TTR gene sequencing. A total of 4459 patients were included in this study; 37% had final diagnosis of ATTR amyloidosis; 27% light chain amyloidosis; 0.7% other types of amyloidosis; 21.3% had no amyloid and 14% had no data. TTR variants were found in 770 (17%) cases; the most prevalent were p.V142I, p.T80A, and p.V50M identified in 42, 25, and 16%, respectively. The median age at referral in each group was: 76 (range 47-93), 66 (40-81), and 45 years (21-86), respectively. Overall 42 rare or novel variants were identified. Forty-two percent patients with ATTRm died at a median age of 73 years (33-89) with a median survival from diagnosis of 50 months. ATTRwt was the final diagnosis in 20% of patients undergoing genetic testing. Our findings of TTR variants in 17% of screened patients highlight the need for routine genetic testing in the evaluation of suspected ATTR amyloidosis.