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

Hypertrophe Kardiomyopathien und die kardiale ATTR-Amyloidose – eine aktuelle Übersicht für den klinischen Alltag

Hypertrophe obstruktive Kardiomyopathie Mavacamten, der erste Myosin-Aktivator, konnte erfolgreich in dem EXPLORER-HCM-Studienprogramm getestet werden. Lebensqualität und linksventrikuläre Druckgradienten-Abnahme wurden optimiert. Ob damit jedoch auch die Überlebensrate und Prognose der betroffenen Patienten verbessert wird, kann bis heute noch nicht gesagt werden. Die europäischen Zulassungsbehörden sehen allerdings bisher die Ergebnisse als so bedeutsam an, dass mit einer Führung der Substanzklasse vielleicht schon in den nächsten 6–8 Monaten zu rechnen ist. In den USA ist die Substanz bereits seit April 2022 zugelassen. Der Einsatz der Substanz bei HCM-Patienten ohne Obstruktion wird ebenfalls zurzeit untersucht.

Kardiale Transthyretin-Amyloidosen Kardiale Amyloidosen haben meist eine gute Ejektionsfraktion, jedoch sind auch EF mit 40 oder < 30 % möglich. Das Auftreten einer kardialen Amyloidose bei Patienten mit der Symptomatik einer Herzinsuffizienz mit erhaltener Ejektionsfraktion (HFpEF) ist in bis zu 15 % der Fälle nachzuweisen. Tafamidis ist die einzige zurzeit zugelassene erfolgreiche Therapiemöglichkeit bei Patienten mit kardialer ATTR-Amyloidose. Dies wurde auch durch weitere Beobachtungsregister der ATTR-ACT-Studie gezeigt. Für die Klinik ist zusätzlich wichtig, dass die Amyloidose auch die Aortenklappe befällt. Zahlreiche Patienten entwickeln somit auch eine Aortenstenose, die erkannt und meist interventionell zu behandeln ist.

Amyloidosis from the patient perspective: the French daily impact of amyloidosis study

BACKGROUND

Amyloidosis is a complex group of rare conditions. For patients, amyloidosis is severely debilitating: physically and psychologically. Currently, data are lacking to evaluate the medical, economic, and social burden of systemic amyloidosis.

OBJECTIVE

To analyse the patient burden according to the main types of systemic amyloidosis.

METHODS

The French Daily Impact of Amyloidosis study was an observational, cross-sectional and non-interventional study. Adults diagnosed with light chain (AL), transthyretin (ATTR), amyloid A (AA) and other rare forms of amyloidosis were eligible. Data regarding amyloidosis prevalence, diagnosis, management, and impact on everyday life were collected using a study-specific survey built by the Association Française Contre l'Amylose (AFCA) and the four French National Referral Centres for Amyloidosis.

RESULTS

A total of 603 patients, predominantly male (65%) with an average age of 66.8 years, including 170 AL, 224 ATTRv, 109 ATTRwt and 25 AA amyloidosis patients, completed the study-specific survey. The median delay from presentation to confirmed diagnosis was 27.4 months but varied according to amyloidosis type. Patients before diagnosis had breathlessness (49%), tingling sensation (33%), pain (28%), difficulty in walking (28%) and weight loss (22%). Amyloidosis was most frequently suspected (49%) and confirmed (57%) in local hospitals but managed in French amyloidosis referral centres (58%). Patients often reported problems with mobility, usual activities, pain/discomfort and anxiety/depression, but not with self-care.

CONCLUSIONS

Systemic amyloidosis severely impacts daily life. The delay to confirmed amyloidosis diagnosis needs to be reduced. Early, effective treatment is required to optimise patient benefits.

Cardiomyopathy correlates to nerve damage in p.A117S late-onset transthyretin amyloid polyneuropathy

Objective

Late‐onset hereditary transthyretin amyloidosis with polyneuropathy (ATTRv‐PN) is often associated with heart involvement. Recent advances in cardiac imaging allow the detection of cardiac amyloidosis. This study aimed to explore cardiomyopathy by cardiac imaging and its clinical correlates with polyneuropathy in late‐onset ATTRv‐PN.

Methods

Polyneuropathy was assessed by intraepidermal nerve fiber (IENF) density, nerve conduction study (NCS), autonomic function tests, quantitative sensory testing, and clinical questionnaires. Cardiomyopathy was evaluated by echocardiography, ^99mTc‐pyrophosphate (PYP) single‐photon emission computed tomography (SPECT) imaging, cardiac magnetic resonance imaging (CMR), and serum Pro‐B‐type natriuretic peptide. Healthy controls and patients with Brugada syndrome were enrolled for comparison of CMR.

Results

Fifty late‐onset ATTRv‐PN patients (38 men, 46 with p. A117S mutation), aged 63.7 ± 5.5 years, of polyneuropathy disability stage 1–4 were enrolled. All patients presented polyneuropathy in NCS, and 74.5% of patients had reduced IENF density in distal legs. All patients showed significant radiotracer uptake in the heart on ^99mTc‐PYP SPECT imaging, and 87.8% of patients had abnormally increased left ventricular (LV) septum thickness on echocardiography. CMR showed longer myocardial native T1, larger extracellular volume, greater LV mass index, and higher LV mass to end‐diastolic volume ratio in ATTRv‐PN patients than healthy controls and patients with Brugada syndrome. These CMR parameters were associated with skin denervation, absent sympathetic skin responses, elevated thermal thresholds, worsened NCS profiles, and functional deficits of polyneuropathy.

Interpretation

Late‐onset ATTRv‐PN coexisted with cardiomyopathy regardless of the clinical severity of polyneuropathy. The cardiac amyloid burden revealed by CMR was correlated with pathophysiology and clinical disability of nerve degeneration.

Transthyretin cardiac amyloidosis

Transthyretin cardiac amyloidosis (ATTR-CA) is an increasingly recognized cause of heart failure (HF) and mortality worldwide. Advances in non-invasive diagnosis, coupled with the development of effective treatments, have shifted ATTR-CA from a rare and untreatable disease to a relatively prevalent condition that clinicians should consider on a daily basis. Amyloid fibril formation results from age-related failure of homoeostatic mechanisms in wild-type ATTR (ATTRwt) amyloidosis (non-hereditary form) or destabilizing mutations in variant ATTR (ATTRv) amyloidosis (hereditary form). Longitudinal large-scale studies in the United States suggest an incidence of cardiac amyloidosis in the contemporary era of 17 per 100 000, which has increased from a previous estimate of 0.5 per 100 000, which was almost certainly due to misdiagnosis and underestimated. The presence and degree of cardiac involvement is the leading cause of mortality both in ATTRwt and ATTRv amyloidosis, and can be identified in up to 15% of patients hospitalized for HF with preserved ejection fraction. Associated features, such as carpal tunnel syndrome, can preceed by several years the development of symptomatic HF and may serve as early disease markers. Echocardiography and cardiac magnetic resonance raise suspicion of disease and might offer markers of treatment response at a myocardial level, such as extracellular volume quantification. Radionuclide scintigraphy with 'bone' tracers coupled with biochemical tests may differentiate ATTR from light chain amyloidosis. Therapies able to slow or halt ATTR-CA progression and increase survival are now available. In this evolving scenario, early disease recognition is paramount to derive the greatest benefit from treatment.

Impact of cardiac amyloidosis on outcomes of patients hospitalized with heart failure

BACKGROUND

Amyloidosis is a multi-systemic disease potentially leading to failure of affected organs. We aimed to investigate prevalence and prognostic implications of cardiac amyloidosis of any etiology on outcomes of hospitalized patients with heart failure (HF) in Germany.

METHODS

We analyzed data of the German nationwide inpatient sample (2005-2018) of patients hospitalized for HF (including myocarditis with HF and heart transplantation with HF). HF patients with amyloidosis (defined as cardiac amyloidosis [CA]) were compared with those HF patients without amyloidosis and impact of CA on outcomes was assessed.

RESULTS

During this fourteen-year observational period 5,478,835 hospitalizations for HF were analyzed. Amyloidosis was coded in 5,407 HF patients (0.1%). CA prevalence was 1.87 hospitalizations per 100,000 German population. CA patients were younger (75.0[IQR 67.0-80.0]vs.79.0[72.0-85.0]years, p < 0.001), predominantly male (68.9%) and had a higher prevalence of cancer (14.8% vs. 3.6%, p < 0.001). Adverse in-hospital events including necessity of transfusions of blood constituents (7.1% vs. 5.4%, p < 0.001) and cardio-pulmonary resuscitation (CPR, 2.7% vs. 1.4%; p < 0.001) were more frequent in CA. CA was independently associated with acute kidney failure (OR 1.40 [95%CI 1.28-1.52], p < 0.001), CPR (OR 1.58 [95%CI 1.34-1.86], p < 0.001), intracerebral bleeding (OR 3.13 [95%CI 1.68-5.83], p < 0.001) and in-hospital mortality between the 5 and 8th decade of life, but in-hospital mortality was strongly influenced by cancer.

CONCLUSIONS

CA was identified as an independent risk factor for complications and in-hospital mortality in HF patients, whereby it has to be mentioned that amyloidosis subtypes could not differentiated in the present study. Physicians should be aware of this issue concerning treatments and monitoring of CA-patients.

Red flags for the diagnosis of cardiac amyloidosis: simple suggestions to raise suspicion and achieve earlier diagnosis

Cardiac amyloidosis is an infiltrative disease characterized by extracellular deposition of insoluble amyloid fibrils in the heart leading to organ dysfunction. Despite recent diagnostic advances, the diagnosis of cardiac amyloidosis is often delayed or even missed. Furthermore, a long diagnostic delay is associated with adverse outcomes, with the early diagnosed patients showing the longest survival. In this narrative review we aimed to summarize the 'red flags' that may facilitate the correct diagnosis. The red flags may be classified as clinical, biohumoral, electrocardiographic, echocardiographic, and cardiac magnetic resonance features and should promptly raise the suspicion of cardiac amyloidosis in order to start a correct diagnostic pathway and targeted treatment strategies that may improve patients' outcomes.

Clinical manifestation, economic burden, and mortality in patients with transthyretin cardiac amyloidosis

Background

Transthyretin cardiac amyloidosis, also known as transthyretin cardiomyopathy (ATTR-CM) is a poorly-recognized disease with delayed diagnosis and poor prognosis. This nationwide population-based study aimed to identify disease manifestations, economic burden, and mortality of patients with ATTR-CM.

Methods

Data of newly diagnosed patients with ATTR-CM between 2013 and 2018 from the Korean National Health Insurance Service were used, covering the entire population. Patient characteristics included comorbidities, medical procedures, and medication. Healthcare resource utilization and medical costs were observed as measures of the economic burden. The Kaplan–Meier survival curve and years of potential life lost (YPLL) from the general population were estimated for disease burden with ATTR CM.

Results

A total of 175 newly diagnosed patients with ATTR-CM were identified. The most common cardiac manifestation was hypertension (51.3%), while the most common non-cardiac manifestation was musculoskeletal disease (68.0%). Mean medical costs at the post-cohort entry date were significantly higher than those at the pre-cohort entry date ($1,864 vs. $400 per patient per month (PPPM), p < 0.001). Of the total medical costs during the study period, the proportion of inpatients cost was 12.9 times higher than the outpatients cost ($1,730 and $134 PPPM, respectively). The median survival time was 3.53 years from the first diagnosis of ATTR-CM, and the mean (SD) YPLL was 13.0 (7.7).

Conclusions

Patients with ATTR-CM had short survival and high medical costs. To reduce the clinical and economic burdens, carefully examining manifestations of disease in patients can help with early diagnosis and treatment.

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.

Clinical recommendations to diagnose and monitor patients with transthyretin amyloid cardiomyopathy in Asia

Transthyretin amyloid cardiomyopathy (ATTR‐CM) is a debilitating and life‐threatening condition with a heterogeneous clinical presentation. Recent guidelines from the United States and Europe have been published to guide clinical practice and to facilitate management conformity by covering current diagnostic and treatment strategies for patients with ATTR‐CM. These guidelines highlight the importance of an early diagnosis to optimize therapeutic outcomes, specifying the use of tests and imaging techniques to allow accurate, noninvasive diagnosis of ATTR‐CM. However, as regional practice variations across Asia may limit access to healthcare, availability of specific tests, and expertise in assessing diagnostic images, there is an ongoing need to provide an Asian perspective on these clinical guidelines. This review article provides practical recommendations for the diagnosis and monitoring of patients with ATTR‐CM in Asia, highlighting the need for additional guidelines to support a broad and diverse population, consider differing healthcare systems and diagnostic testing availability, and provide a flexible yet robust algorithm.

Baseline characteristics and secondary medication adherence among Medicare patients diagnosed with transthyretin amyloid cardiomyopathy and/or receiving tafamidis prescriptions: A retrospective analysis of a Medicare cohort

BACKGROUND: Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underdiagnosed, life-threatening condition that mostly affects older persons. In May 2019, regulatory approval of tafamidis provided the first pharmacologic treatment of ATTR-CM. In the pivotal phase 3 Transthyretin Amyloidosis Cardiomyopathy Clinical Trial (ATTR-ACT), 97.2% of patients were classified as adherent (defined as taking ≥ 80% of scheduled doses). Given its recent approval, there is limited real-world evidence examining patient adherence to tafamidis. OBJECTIVE: To evaluate adherence patterns, demographics, and clinical characteristics of patients in the United States receiving tafamidis prescriptions through Medicare. Secondarily, we aimed to evaluate concomitant medications filled by this patient population. METHODS: We conducted a retrospective cohort study of US Medicare claims data, limited by the Health Insurance Portability and Accountability Act of 1996, in adult patients with an adjudicated pharmacy claim for tafamidis (tafamidis free acid 61-mg capsule once daily or tafamidis meglumine four 20-mg capsules once daily) between May 1, 2019, and June 30, 2021. Gaps in therapy were measured using day gaps between prescription refills and continuous measure of medication gaps. Implementation adherence was assessed through modified medication possession ratio (MPRm), medication refill adherence (MRA), and proportion of days covered (PDC). Patients were grouped based on Medicare coverage. Patients were analyzed by subgroups based on age and at the zip code level, via distressed communities index quartiles and rural-urban tiers. RESULTS: A total of 3,558 patients who received a prescription fill of a tafamidis formulation were identified using Medicare Fee-for-Service (FFS) and Medicare Advantage (MA) claims data from May 1, 2019, to June 30, 2021. The characteristics of this patient population were consistent with published literature, as 98.6% were older than 65 years, 53.4% were between 75 years and 84 years, and 81.5% were male. In the patient population receiving tafamidis refills, adherence was high across all 3 measures, with mean MPRm greater than 90% and mean MRA greater than 80%, across all age groups. Mean PDC adherence rates were 79% or more across all age groups. Concomitant medications were generally indicated for heart failure and thrombosis. Among monotherapy groups with similar demographic makeup, adherence was significantly higher among users of tafamidis free acid vs tafamidis meglumine (P < 0.0001 across all mean adherence measures). CONCLUSIONS: Our results demonstrate that real-world adherence to tafamidis in the Medicare population is high, regardless of age, zip code-level socioeconomic quartile, or geography. Adherence was higher among patients receiving tafamidis free acid, suggesting that the enhanced convenience of a single capsule once daily may positively contribute to adherence among patients with ATTR-CM. DISCLOSURES: Darrin Benjumea is an employee of Genesis Research who has been contracted by Pfizer, Inc., for involvement in this study. Andrew Peterson is an employee of University of the Sciences who has been contracted by Pfizer, Inc., for involvement in this study. Zach Bredl is an employee of Care Journey who has been contracted by Pfizer, Inc., for involvement in this study. Anuja Roy, Nick Marchant, Jose Alvir, Rahul Bhambri, Jason Kemner, and Bhash Parasuraman are employees of Pfizer, Inc., and own stock and/or stock options. This study was supported by Pfizer, Inc.

Incidence and predictors of worsening heart failure in patients with wild-type transthyretin cardiac amyloidosis

BACKGROUND

Prognostic markers of survival have been identified in wild-type transthyretin amyloidosis (ATTRwt), but limited data exist with respect to hospitalizations with worsening heart failure (WHF). Predictive markers of WHF have yet to be identified.

METHODS

From April 2017 to February 2021, 104 patients with ATTRwt were diagnosed and prospectively followed from the time of diagnosis to the time of death or the censoring date of 1 February 2021. Baseline patient characteristics, biomarkers, and advanced echocardiography were used to predict hospitalization with WHF.

RESULTS

During the median follow-up period of 23 months, 51% of patients were hospitalized due to WHF. Seventy-three per cent of patients with WHF were admitted at least twice. Patients with WHF during the first year had significantly poorer survival (P < 0.001). Independent predictors of WHF during follow-up were pacemaker implantation prior to diagnosis (PMI, P = 0.037) and right atrial volume index (RAVi, P = 0.008). Patients with PMI had a higher left ventricular mass index and poorer left ventricular and right ventricular systolic function indicating a more advanced stage of amyloid disease.

CONCLUSIONS

A high incidence and recurrence of hospital admissions with WHF were demonstrated in contemporary patients with ATTRwt, which was associated with reduced survival. Patients with pacemaker devices prior to ATTRwt diagnosis experienced more frequent hospitalizations with WHF. PMI and right atrial enlargement were identified as independent predictors of WHF during follow-up.

Prevalence and Clinical Outcomes of Transthyretin Amyloidosis: A Systematic Review and Meta-analysis

BACKGROUND

Systematic evidence on the prevalence and clinical outcome of transthyretin amyloidosis (ATTR) is missing. We explored: a) the prevalence of cardiac amyloidosis in various patient subgroups, b) survival estimates for ATTR subtypes and c) the effects of novel therapeutics on the natural course of disease.

METHODS

A systematic review of literature published in Medline before 31/12/2021 was performed for the prevalence of cardiac amyloidosis & all-cause mortality of ATTR patients. Extracted data included sample size, age, sex, and all-cause mortality at 1, 2 and 5-years. Subgroup analyses were performed for ATTR subtype i.e., wild type ATTR (wtATTR) vs. hereditary ATTR (htATTR), htATTR genotypes and treatment subgroups.

RESULTS

We identified a total of 62 studies (n=277,882 individuals) reporting the prevalence of cardiac amyloidosis, which was high among patients with a hypertrophic cardiomyopathy phenotype, HFpEF, and elderly with aortic stenosis. Data on ATTR mortality were extracted from 95 studies (n=18,238 ATTR patients). Patients with wtATTR were older (p=7x10^-10 ) and more frequently male (p=5x10^-20 ) vs. htATTR. The 2-year survival of ATTR was 73.3% (95%CI 71.6-76.2); for non-subtyped ATTR 70.4% (95%CI 66.9-73.9), for wtATTR (76.0%, 95%CI: 73.0-78.9) and for htATTR (77.2%, 95%CI: 74.0-80.4); in meta-regression analysis wtATTR was associated with higher survival after adjusting for confounders. There was an interaction between survival and htATTR genotypes (p=10^-15 , Val30Met having the lowest and Val122Ile/Thr60Ala the highest mortality). ATTR 2-year survival was higher on tafamidis/patisiran compared to natural disease course (79.9%, 95%CI: 74.4-85.3 vs. 72.4%, 95%CI 69.8-74.9, p<0.05).

CONCLUSIONS

We report the prevalence of ATTR in various population subgroups and provide survival estimates for the natural course of disease and the effects of novel therapeutics. Important gaps in worldwide epidemiology research in ATTR were identified. This article is protected by copyright. All rights reserved.

Clinical and Genetic Evaluation of People with or at Risk of Hereditary ATTR Amyloidosis: An Expert Opinion and Consensus on Best Practice in Ireland and the UK

Hereditary transthyretin-mediated amyloidosis (hATTR) is challenging to diagnose early owing to the heterogeneity of clinical presentation, which differs according to the TTR gene variant and its penetrance in each individual. The TTR variants seen most frequently in the UK and Ireland (T80A, V142I and V50M) differ to those commonly occurring in other geographic locations and warrant a specific consideration for diagnosis and genetic testing. In addition, recent availability of treatment for this condition has reinforced the need for a more consistent approach to the management of patients, including access to specialist services, genetic testing and counselling, and clinical investigation for families living in the UK and Ireland. A multidisciplinary panel of experts from the UK and Ireland was convened to identify the current challenges, provide recommendations, and develop a consensus for the diagnosis and screening of people with, or at risk of, hATTR. Over a series of meetings, experts shared their current practices and drafted, refined and approved a consensus statement. This consensus statement provides recommendations for three different groups: (1) people with symptoms raising a possibility of hATTR amyloidosis; (2) people with biopsy-confirmed hATTR amyloidosis; and (3) people without symptoms who may have hATTR amyloidosis (i.e. relatives of people with identified TTR variants). For each group, recommendations are made for the required steps for the diagnosis and follow-up of symptomatic patients, and for guidance on the specialist support for counselling and pre-symptomatic genetic testing of at-risk individuals. This guidance is intended to be practical and based on available evidence. The aim is for regional amyloid specialist centres to provide timely diagnosis, clinical screening, and treatment for individuals and their families with hATTR amyloidosis.

A simple staging system using biomarkers for wild-type transthyretin amyloid cardiomyopathy in Japan

AIMS

It has been reported that a staging system combining N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin T (hs-cTnT) or estimated glomerular filtration rate (eGFR) is useful in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). However, these studies were mainly conducted in Western countries, and their usefulness for the Japanese population is unclear. We examined and validated the staging system using hs-cTnT, eGFR, and B-type natriuretic peptide (BNP) in Japanese patients with ATTRwt-CM.

METHODS AND RESULTS

We retrospectively evaluated 176 patients with ATTRwt-CM. The cut-off values of hs-cTnT and eGFR were selected as 0.05 ng/mL and 45 mL/min/1.73 m2 , respectively, based on a previous report. The optimal cut-off value of BNP was 255.6 pg/mL to predict all-cause mortality (sensitivity, 75%; specificity, 58%; area under the curve, 0.69; 95% confidence interval [CI], 0.61-0.78; P < 0.001) based on a receiver operating characteristic curve. We defined the cut-off value of BNP as 250 pg/mL. Increased hs-cTnT (>0.05 ng/mL) and BNP (>250 pg/mL) and decreased eGFR (<45 mL/min/1.73 m2 ) were significant predictors of poor prognosis (P < 0.05). We calculated the score by adding 1 point if hs-cTnT and BNP levels increased or eGFR decreased by more than the cut-off value. The hazard ratio of all-cause death adjusted by age and sex, using score 0 as a reference, was 0.44 (95% CI 0.08-2.49, P = 0.44) for score 1, 3.69 (95% CI 1.21-11.21, P = 0.02) for score 2, and 5.40 (95% CI 1.57-18.54, P = 0.007) for score 3. We divided patients into a low score group (0-1 point) and high score group (2-3 points). Kaplan-Meier analyses revealed significant differences in all-cause death and rehospitalization for heart failure (log rank test; P < 0.001), and after adjusting for sex and age, the hazard ratio of all-cause death was 6.96 (95% Cl 2.88-16.83, P < 0.001) and that for rehospitalization for heart failure was 4.27 (95% Cl 2.26-8.07, P < 0.001) in the high-risk group, compared with those in the low-risk group. The median survival period was 32.0 months in the high-risk group.

CONCLUSIONS

This simple staging system, which combines hs-cTnT, BNP, and eGFR, was useful for predicting prognosis in Japanese patients with ATTRwt-CM. This system can objectively evaluate the disease progression of ATTRwt-CM and may be useful for patient selection for disease-modifying therapy.

Suspicion, screening, and diagnosis of wild-type transthyretin amyloid cardiomyopathy: a systematic literature review

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt CM) is a more common disease than previously thought. Awareness of ATTRwt CM and its diagnosis has been challenged by its unspecific and widely distributed clinical manifestations and traditionally invasive diagnostic tools. Recent advances in echocardiography and cardiac magnetic resonance (CMR), non-invasive diagnosis by bone scintigraphy, and the development of disease-modifying treatments have resulted in an increased interest, reflected in multiple publications especially during the last decade. To get an overview of the scientific knowledge and gaps related to patient entry, suspicion, diagnosis, and systematic screening of ATTRwt CM, we developed a framework to systematically map the available evidence of (i) when to suspect ATTRwt CM in a patient, (ii) how to diagnose the disease, and (iii) which at-risk populations to screen for ATTRwt CM. Articles published between 2010 and August 2021 containing part of or a full diagnostic pathway for ATTRwt CM were included. From these articles, data for patient entry, suspicion, diagnosis, and screening were extracted, as were key study design and results from the original studies referred to. A total of 50 articles met the inclusion criteria. Of these, five were position statements from academic societies, while one was a clinical guideline. Three articles discussed the importance of primary care providers in terms of patient entry, while the remaining articles had the cardiovascular setting as point of departure. The most frequently mentioned suspicion criteria were ventricular wall thickening (44/50), carpal tunnel syndrome (42/50), and late gadolinium enhancement on CMR (43/50). Diagnostic pathways varied slightly, but most included bone scintigraphy, exclusion of light-chain amyloidosis, and the possibility of doing a biopsy. Systematic screening was mentioned in 16 articles, 10 of which suggested specific at-risk populations for screening. The European Society of Cardiology recommends to screen patients with a wall thickness ≥12 mm and heart failure, aortic stenosis, or red flag symptoms, especially if they are >65 years. The underlying evidence was generally good for diagnosis, while significant gaps were identified for the relevance and mutual ranking of the different suspicion criteria and for systematic screening. Conclusively, patient entry was neglected in the reviewed literature. While multiple red flags were described, high-quality prospective studies designed to evaluate their suitability as suspicion criteria were lacking. An upcoming task lies in defining and evaluating at-risk populations for screening. All are steps needed to promote early detection and diagnosis of ATTRwt CM, a prerequisite for timely treatment.

Correlation of Quantitative 99mTc DPD Scintigraphy With Echocardiographic Alterations in Left Atrial Parameters in Transthyretin Amyloidosis

AIM

Cardiac transthyretin amyloidosis (ATTR) patients have high rates of atrial arrhythmias. We evaluated echocardiographic structural and functional left atrial (LA) parameters and correlated these with technetium-99m 3,3-diphosphono-1,2-propanodicarboxylic acid (^99mTc-DPD) bone scintigraphy tracer uptake within the LA in ATTR patients.

METHODS

ATTR patients (wild-type, hereditary and asymptomatic transthyretin [TTR] variant carriers) who had undergone ^99mTc-DPD and transthoracic echocardiogram (TTE) were selected. Quantitative ^99mTc-DPD uptake analysis and echocardiographic evaluation of LA structural and functional parameters was performed.

RESULTS

Forty (40) ATTR patients (wild-type n=17; hereditary ATTR and TTR variant carriers n=23; median age 68.8±22 years) were included. TTE parameters including indexed LA minimum (LAV_min) (r=0.66), and LA maximum volumes (LAV_max) (r=0.64), LA emptying fraction (LAEF) (r=-0.68), LA function index (LAFI) (r=-0.70) and reservoir strain (ƐR) (r=-0.70) (p<0.001 for all) demonstrated good correlation to LA tracer uptake. Normal LA volume (LAV_min and LAV_max) and function (LAEF, LAFI and ƐR) was observed in hereditary ATTR and TTR variant carriers without cardiac tracer uptake. The subgroup of ATTR patients with atrial fibrillation/flutter demonstrated increased LAV_min and LAV_max with further reduction in LA function (LAEF, LAFI and ƐR). Receiver operating characteristic curves demonstrated strong diagnostic accuracies for LA structural (LAV_min and LAV_max; area under the curve [AUC] of 0.83 and 0.84 respectively) and functional (LAEF, LAFI and ƐR; AUC 0.81, 0.88 and 0.85, respectively) parameters.

CONCLUSION

Left atrial structural and functional parameters demonstrated good correlations with quantitative ^99mTc-DPD tracer LA uptake. Echocardiography and ^99mTc-DPD scintigraphy may have significant roles in identification and surveillance of ATTR patients likely to develop atrial arrhythmias.

Prognostic significance of incidental suspected transthyretin amyloidosis on routine bone scintigraphy

BACKGROUND

Transthyretin amyloidosis (ATTR) is an occasional incidental finding on bone scintigraphy. We studied its prognostic impact in elderly patients.

METHODS

The study population consisted of 2000 patients aged over 70 years who underwent bone scintigraphies with clinical indications in three nuclear medicine departments (Kymenlaakso, Jorvi and Meilahti hospitals) in Finland. All studies were performed using 99mTechnetium labeled hydroxymethylene diphosphonate (HMDP). ATTR was suspected in patients with ≥grade 2 Perugini grade uptake (grade 0-3). Heart-to-contralateral ratio (H/CL) of ≥ 1.30 was considered positive for ATTR. The overall and cardiovascular mortality were obtained from the Finnish National Statistical Service.

RESULTS

There were a total of 1014 deaths (51%) and 177 cardiovascular deaths (9%) during median follow-up of 4 ± 2 years. ATTR was suspected in 69 patients (3.6%) of which 54 (2.7%) had grade 2 and 15 (.8%) had grade 3 uptake and in 47 patients (2.4%) by H/CL ratio. In multivariate analyses age, bone metastasis, H/CL ratio and grade 3 uptake were independent predictors of overall and cardiovascular mortality. Grade 2 uptake was a predictor of cardiovascular mortality.

CONCLUSIONS

A suspected ATTR as an incidental finding on bone scintigraphy predicts elevated overall and cardiovascular mortality in elderly patients.

Novel approaches to diagnosis and management of hereditary transthyretin amyloidosis

Hereditary transthyretin amyloidosis (ATTRv) is a severe, adult-onset autosomal dominant inherited systemic disease predominantly affecting the peripheral and autonomic nervous system, heart, kidney and the eyes. ATTRv is caused by mutations of the transthyretin (TTR) gene, leading to extracellular deposition of amyloid fibrils in multiple organs including the peripheral nervous system. Typically, the neuropathy associated with ATTRv is characterised by a rapidly progressive and disabling sensorimotor axonal neuropathy with early small-fibre involvement. Carpal tunnel syndrome and cardiac dysfunction frequently coexist as part of the ATTRv phenotype. Although awareness of ATTRv polyneuropathy among neurologists has increased, the rate of misdiagnosis remains high, resulting in significant diagnostic delays and accrued disability. A timely and definitive diagnosis is important, given the emergence of effective therapies which have revolutionised the management of transthyretin amyloidosis. TTR protein stabilisers diflunisal and tafamidis can delay the progression of the disease, if treated early in the course. Additionally, TTR gene silencing medications, patisiran and inotersen, have resulted in up to 80% reduction in TTR production, leading to stabilisation or slight improvement of peripheral neuropathy and cardiac dysfunction, as well as improvement in quality of life and functional outcomes. The considerable therapeutic advances have raised additional challenges, including optimisation of diagnostic techniques and management approaches in ATTRv neuropathy. This review highlights the key advances in the diagnostic techniques, current and emerging management strategies, and biomarker development for disease progression in ATTRv.

Practical guidelines for the diagnosis and treatment of transthyretin amyloid cardiomyopathy (ATTR-CM or transthyretin cardiac amyloidosis)

This paper summarizes the data from updated international protocols and guidelines for diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM). The invasive and non-invasive diagnosis techniques and their combinations are briefly reviewed; the evidentiary foundations for each diagnostic option and tool are analyzed. The paper describes a customized algorithm for sequential diagnosis and differential diagnosis of patients with suspected ATTR-CM with allowance for the combination of clinical signs and diagnostic findings. Along with the awareness of primary care providers about the red flags of the disease and visualization criteria, as well as providing information to the patients about the possibility of performing therapy of ATTR amyloidosis and the risks of delayed diagnosis, the proposed algorithm enables timely patient routing and prescribing specific treatment.

Prevalence, characteristics, and mortality of patients with transthyretin amyloid cardiomyopathy in the Nordic countries

Aims

Transthyretin amyloid cardiomyopathy (ATTR‐CM) is a progressive condition caused by deposition of transthyretin amyloid fibrils in the heart and is associated with poor quality of life and a shortened lifespan. This study aimed to describe the prevalence, clinical characteristics, and mortality of patients with ATTR‐CM, using multiple national health registers in Denmark, Finland, Norway, and Sweden.

Methods and results

Transthyretin amyloid cardiomyopathy patients were identified during 2008–2018 using a combination of diagnosis codes for amyloidosis and heart disease and were matched to patients with non‐ATTR heart failure (HF). An identical study design was used in each country to facilitate comparison and aggregation of results. A total of 1930 ATTR‐CM patients were identified from national health registers in the four countries. In 2018, prevalence of ATTR‐CM per 100 000 inhabitants ranged from 1.4 in Denmark to 5.0 in Sweden; a steep increase over time was observed in Sweden and Norway. Median survival from diagnosis was 30 months for ATTR‐CM patients and 67 months for matched HF patients. Survival was significantly lower for female than for male ATTR‐CM patients (median survival: 22 and 36 months), while no significant difference was observed in the HF cohort.

Conclusions

This study provides the first nationwide estimates of the prevalence, clinical characteristics, and mortality of patients with ATTR‐CM, using identical study design across several countries. Findings corroborate previous case series showing high mortality in ATTR‐CM, two‐fold higher than for other HF patients and higher in women than men, highlighting the need for more precise and early diagnosis to reduce the disease burden.

Imaging-Guided Treatment for Cardiac Amyloidosis

Purpose of Review

This review will explore the role of cardiac imaging in guiding treatment in the two most commonly encountered subtypes of cardiac amyloidosis (immunoglobulin light-chain amyloidosis [AL] and transthyretin amyloidosis [ATTR]).

Recent Findings

Advances in multi-parametric cardiac imaging involving a combination of bone scintigraphy, echocardiography and cardiac magnetic resonance imaging have resulted in earlier diagnosis and initiation of treatment, while the evolution of techniques such as longitudinal strain and extracellular volume quantification allow clinicians to track individuals’ response to treatment. Imaging developments have led to a deeper understanding of the disease process and treatment mechanisms, which in combination result in improved patient outcomes.

Summary

The rapidly expanding treatment regimens for cardiac amyloidosis have led to an even greater reliance on cardiac imaging to help establish an accurate diagnosis, monitor treatment response and aid the adjustment of treatment strategies accordingly.

Prognostic Value of 99mTc-HMDP Scintigraphy in Elderly Patients With Chronic Heart Failure

BACKGROUND

This study evaluated the prevalence and prognostic significance of cardiac transthyretin amyloidosis (ATTR) diagnosed using ^99mTc- hydroxymethylene-diphosphonate (^99mTc-HMDP) scintigraphy in an elderly heart failure population.

METHODS

This retrospective study included 335 patients aged >70 years with heart failure and who underwent ^99mTc-HMDP scintigraphy due to non-cardiac reasons in three imaging centres in Finland (Kymenlaakso Central Hospital, Jorvi Central Hospital, and Meilahti University Hospital). A Perugini grade >2 and heart-to-contralateral ratio (H/CL) of ≥1.30 were considered positive for cardiac ATTR. The overall and cardiovascular mortality were obtained from the national statistical service (Statistics Finland).

RESULTS

There were 234 deaths, of which 70 were classified as being due to cardiovascular causes during a median follow-up of 1 (1-3) year. Transthyretin amyloidosis was diagnosed in 22 patients (6.6%) using visual analysis and 17 patients using the H/CL ratio (5.1%). Patients with ATTR were older (85±5 vs 80±5 yrs; p=0.002) and had higher N-terminal pro-brain natriuretic peptide (NT-ProBNP) levels (1,451 [813-3,799] vs 6,192 [2,030-8,833] ng/L; p=0.02). Age, bone metastases, and glomerular filtration rate were independent predictors of overall mortality in multivariable analysis. Age, glomerular filtration rate, ≥grade 2 visual cardiac uptake, and H/CL ratio were independent predictors of cardiovascular mortality.

CONCLUSIONS

Cardiac uptake suggestive of ATTR was found in 5% of elderly patients with chronic heart failure. The presence of cardiac uptake on bone scintigraphy did not convey independent prognostic value on overall mortality but was independently associated with cardiovascular mortality.

The revolution of ATTR amyloidosis in cardiology: certainties, gray zones and perspectives

Transthyretin (TTR) is a tetrameric protein synthesized mostly by the liver. As a result of gene mutations or as an ageing-related phenomenon, TTR molecules may misfold and deposit in the heart and in other organs as amyloid fibrils. Amyloid transthyretin cardiac amyloidosis (ATTR-CA) manifests typically as left ventricular pseudohypertrophy and/or heart failure with preserved ejection fraction and is an underdiagnosed disorder affecting quality of life and prognosis. This justifies the current search for novel tools for early diagnosis and accurate risk prediction, as well as for safe and effective therapies. In this review we will provide an overview of the main unsolved issues and the most promising research lines on ATTR-CA, ranging from the mechanisms of amyloid formation to therapies.

When to Suspect and How to Approach a Diagnosis of Amyloidosis

Diagnoses of amyloidosis, particularly transthyretin amyloid cardiomyopathy (ATTR-CM), are steadily increasing throughout the world, but the condition remains underdiagnosed. Patients with amyloidosis may present to a range of medical and surgical specialties, often with multisystemic disease, and a high index of clinical suspicion is required for diagnosis. Bone scintigraphy and cardiovascular magnetic resonance (CMR) imaging offer highly sensitive and specific imaging modalities for cardiac amyloidosis. Histological confirmation of amyloid deposition and amyloid type remains the cornerstone of diagnosis for most amyloid types, with transthyretin amyloid cardiomyopathy the exception, which may be diagnosed by validated nonbiopsy diagnostic criteria in the majority. Histological diagnosis of amyloid has been enhanced by laser capture microdissection and tandem mass spectrometry. Early diagnosis and treatment prior to the development of end-organ damage remains essential to improving morbidity and mortality for patients with amyloidosis.

[Cardiac arrhythmias and amyloidosis]

Cardiac amyloidosis (CA) is a form of cardiomyopathy characterized by the extracellular deposit of protein fibers in the myocardium, leading to the development of heart failure, arrhythmias, and electrical conduction system alterations. It is known that most cardiomyopathies have a close relationship with heart rhythm abnormalities, however, CA is specially related to different kinds of arrhythmias even in pre-diagnosis stages. Arrhythmias like atrial fibrillation are present in up to 70% of patients with CA associated with a high risk of cardioembolic complications independent of the risk stratification. Ventricular arrhythmias are frequent, but the use of implantable cardioverter defibrillator has not been demonstrated to improve survival. The Atrial-Ventricular node disease is also common, and is frequently associated with the implantation of a pacemaker, even in asymptomatic patients. In this review, we clarify the recommendations of the most current guidelines, summarize historical and contemporaneous data and describe evidence-based strategies for the management of arrhythmias and their complications in CA.

Healthcare resource use of patients with transthyretin amyloid cardiomyopathy

Aims

Transthyretin amyloid cardiomyopathy (ATTR‐CM) is the cardiac manifestation of transthyretin amyloidosis (ATTR). The aim of this study was to estimate healthcare resource use for ATTR‐CM patients compared with heart failure (HF) patients, in Denmark, Finland, Norway, and Sweden.

Methods and results

Data from nationwide healthcare registers in the four countries were used. ATTR‐CM patients were defined as individuals diagnosed with amyloidosis and cardiomyopathy or HF between 2008 and 2018. Patients in the ATTR‐CM cohort were matched to patients with HF but without ATTR‐CM diagnosis. Resource use included number of visits to specialty outpatient and inpatient hospital care. A total of 1831 ATTR‐CM and 1831 HF patients were included in the analysis. The mean number of hospital‐based healthcare contacts increased in both the ATTR‐CM and HF cohort during 3 years pre‐diagnosis and was consistently higher for the ATTR‐CM cohort compared with the HF cohort, with 6.1 [CI: 5.9–6.3] vs. 3.2 [CI: 3.1–3.3] outpatient visits and 1.03 [CI: 0.96–1.1] vs. 0.7 [CI: 0.7–0.8] hospitalizations. In the first year following diagnosis, patients with ATTR‐CM continued to visit outpatient care (10.2 [CI: 10.1, 10.4] vs. 5.7 [CI: 5.6, 5.9]) and were admitted to hospital more frequently (3.3 [CI: 3.2, 3.4] vs. 2.5 [CI: 2.5, 2.6]) than HF patients.

Conclusions

Transthyretin amyloid cardiomyopathy imposes a high burden on healthcare systems with twice as many outpatient specialist visits and 50% more hospitalizations in the year after diagnosis compared with HF patients without ATTR‐CM. Studies to investigate if earlier diagnosis and treatment of ATTR‐CM may lower resource use are warranted.

Multimodality Imaging in the Evaluation and Prognostication of Cardiac Amyloidosis

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy resulting from deposition of misfolded immunoglobulin light chains (AL-CA) or transthyretin (ATTR-CA) proteins in the myocardium. Survival varies between the different subtypes of amyloidosis and degree of cardiac involvement, but accurate diagnosis is essential to ensure initiation of therapeutic interventions that may slow or potentially prevent morbidity and mortality in these patients. As there are now effective treatment options for CA, identifying underlying disease pathogenesis is crucial and can be guided by multimodality imaging techniques such as echocardiography, magnetic resonance imaging, and nuclear scanning modalities. However, as use of cardiac imaging is becoming more widespread, understanding optimal applications and potential shortcomings is increasingly important. Additionally, certain imaging modalities can provide prognostic information and may affect treatment planning. In patients whom imaging remains non-diagnostic, tissue biopsy, specifically endomyocardial biopsy, continues to play an essential role and can facilitate accurate and timely diagnosis such that appropriate treatment can be started. In this review, we examine the multimodality imaging approach to the diagnosis of CA with particular emphasis on the prognostic utility and limitations of each imaging modality. We also discuss how imaging can guide the decision to pursue tissue biopsy for timely diagnosis of CA.

Clinical Implications of the Amyloidogenic V122I Transthyretin Variant in the General Population

BACKGROUND

The V122I variant in transthyretin (TTR) is the most common amyloidogenic mutation worldwide. The aim of this study is to describe the cardiac phenotype and risk for adverse cardiovascular outcomes of young V122I TTR carriers in the general population.

METHODS AND RESULTS

TTR genotypes were extracted from whole-exome sequence data in participants of the Dallas Heart Study. Participants with African ancestry, available V122I TTR genotypes (N = 1818) and either cardiac magnetic resonance imaging (n = 1364) or long-term follow-up (n = 1532) were included. The prevalence of V122I TTR carriers (45 ± 10 years) was 3.2% (n/N = 59/1818). The V122I TTR carriers had higher baseline left ventricular wall thickness (8.52 ± 1.82 vs 8.21 ± 1.62 mm, adjusted P = .038) than noncarriers, but no differences in other cardiac magnetic resonance imaging measures (P > .05 for all). Although carrier status was not associated with amino terminal pro-B-type natriuretic peptide (NT-proBNP) at baseline (P = .79), V122I TTR carriers had a greater increase in NT-proBNP on follow-up than noncarriers (median 28.5 pg/mL, interquartile range 11.4-104.1 pg/mL vs median 15.9 pg/mL, interquartile range 0.0-43.0 pg/mL, adjusted P = .018). V122I TTR carriers were at a higher adjusted risk of heart failure (hazard ratio 3.82, 95% confidence interval 1.80-8.13, P < .001), cardiovascular death (hazard ratio 2.65, 95% confidence interval 1.14-6.15, P = .023), and all-cause mortality (hazard ratio 1.95, 95% confidence interval 1.08-3.51, P = .026) in comparison with noncarriers.

CONCLUSIONS

V122I TTR carrier status was associated with a greater increase in NT-proBNP, slightly greater left ventricular wall thickness, and a higher risk for heart failure, cardiovascular death, and all-cause mortality. These findings suggest the need to develop amyloidosis screening strategies for V122I TTR carriers.

Healthcare resource use associated with the diagnosis of transthyretin amyloidosis cardiomyopathy

OBJECTIVES

Our primary aim was to evaluate the healthcare resource use associated with the diagnosis of transthyretin amyloidosis cardiomyopathy. Second, we aim to assess the effect of the number of diagnostic tests and clinical contact points on the total time and costs between symptom onset and diagnosis defining a quantitative hypothetical optimized diagnostic pathway.

SETTING

Clinical and cost data were collected from patients presenting between 2010 and 2018 in a tertiary referral institution in South London involving two participating hospitals.

PARTICIPANTS

Thirty-eight adult patients with a definite diagnosis of transthyretin amyloidosis cardiomyopathy were included, mostly male (n = 28, 74%) and of African-Caribbean descent (n = 23, 64%). We excluded patients without a confirmed transthyretin amyloidosis cardiomyopathy or those on inotersen, patisiran, or diflunisal at point of referral.

PRIMARY AND SECONDARY OUTCOME MEASURES

The average time between first presentation and final diagnosis, and the cost per patient per month. By comparing to a more optimal clinical pathway towards diagnosis, we considered what could be the theoretical gain in terms of time to diagnosis and financial savings.

RESULTS

The average time between first presentation and final diagnosis was 2.74 years. The average cost per patient per month was higher with progressive heart failure symptoms. A hypothetical optimal pathway reduces time to diagnosis of 1.65 to 1.74 years per patient. The potential financial savings are estimated within the range of £3000 to £4800 per patient.

CONCLUSIONS

Patients diagnosed with transthyretin amyloidosis cardiomyopathy have substantial healthcare resource utilization and costs starting from symptom onset. Higher costs were observed with progression in symptoms and appear linked to a delayed diagnosis. The number of additional diagnostic tests and clinical contact points may contribute to this and could represent a path to explore further for important health and cost savings, with more efficient pathways for these patients to be managed.

The role of serial 99mTc-DPD scintigraphy in monitoring cardiac transthyretin amyloidosis

PURPOSE

Cardiac transthyretin amyloidosis is a usually fatal form of restrictive cardiomyopathy for which clinical trials of treatments are ongoing. It is anticipated that quantitative nuclear medicine scintigraphy, which is experiencing growing interest, will soon be used to evaluate treatment efficacy. We investigated its utility for monitoring changes in disease load over a significant time period.

METHODS

Sixty-two treatment-naive patients underwent ^99mTc-labelled 3,3-diphosphono-1,2propanodicarboxylic acid (^99mTc-DPD) scintigraphy two to four times each over a five-year period. Quantitation of cardiac ^99mTc-DPD retention was performed according to two established methods: measurement of heart-to-contralateral ratio (H/CL) in the anterior view (planar) and percentage of administered activity in the myocardium (SPECT).

RESULTS

In total 170 datasets were analysed. Increased myocardial retention of ^99mTc-DPD was demonstrable as early as 12 months from baseline. Year-on-year progression across the cohort was observed using SPECT-based quantitation, though on 30 occasions (27.8%) the change in our estimate was negative.

CONCLUSIONS

The spread of our results was notably high compared to the year-on-year increases. If left unaccounted for, variance may draw fallacious conclusions about changes in disease load. We therefore urge caution in drawing conclusions solely from nuclear medicine scintigraphy on a patient-by-patient basis, particularly across a short time period.

Change in N-terminal pro-B-type natriuretic peptide at 1 year predicts mortality in wild-type transthyretin amyloid cardiomyopathy

OBJECTIVES

Wild-type transthyretin amyloid cardiomyopathy (wtATTR-CM) is a progressive and fatal condition. Although prognosis can be determined at the time of diagnosis according to National Amyloidosis Centre (NAC) transthyretin amyloidosis (ATTR) stage, the clinical course varies substantially between individuals. There are currently no established measures of rate of disease progression. Through systematic analysis of functional, biochemical and echocardiographic disease-related variables we aimed to identify prognostic markers of disease progression in wtATTR-CM.

METHODS

This is a retrospective observational study of 432 patients with wtATTR-CM diagnosed at the UK NAC, none of whom received disease-modifying therapy. The association between mortality from the 12-month timepoint and change from diagnosis to 12 months in a variety of disease-related variables was explored using Cox regression.

RESULTS

Change in N-terminal pro-B-type natriuretic peptide concentration (∆ NT-proBNP) at 12 months from diagnosis was the strongest predictor of ongoing mortality and was independent of both change in other disease-related variables (HR 1.04 per 500 ng/L increase (95% CI 1.01 to 1.07); p=0.003) and a range of known prognostic variables at the time of diagnosis (HR 1.07 per 500 ng/L increase (95% CI 1.02 to 1.13); p=0.007). An increase in NT-proBNP of >500 ng/L, >1000 ng/L and >2000 ng/L during the first year of follow-up occurred in 45%, 35% and 16% of patients, respectively.

CONCLUSION

Change in NT-proBNP concentration during the first year of follow-up is a powerful independent predictor of mortality in wtATTR-CM.

Evaluation of the cardiac amyloidosis clinical pathway implementation: a real-world experience

Aims

The aim of this study is to evaluate the implementation of the cardiac amyloidosis (CA) clinical pathway on awareness among referring cardiologists, diagnostic delay, and severity of CA at diagnosis.

Methods and results

Patients with CA were retrospectively included in this study and divided into two periods: pre-implementation of the CA clinical pathway (2007-18; T1) and post-implementation (2019-20; T2). Patients' and disease characteristics were extracted from electronic health records and compared. In total, 113 patients (mean age 67.8 ± 8.5 years, 26% female) were diagnosed with CA [T1 (2007-18): 56; T2 (2019-20): 57]. The number of CA diagnoses per year has increased over time. Reasons for referral changed over time, with increased awareness of right ventricular hypertrophy (9% in T1 vs. 36% in T2) and unexplained heart failure with preserved ejection fraction (22% in T1 vs. 38% in T2). Comparing T1 with T2, the diagnostic delay also improved (14 vs. 8 months, P < 0.01), New York Heart Association Class III (45% vs. 23%, P = 0.03), and advanced CA stage (MAYO/Gillmore Stage III/IV; 61% vs. 33%, P ≤ 0.01) at time of diagnosis decreased.

Conclusion

After implementation of the CA clinical pathway, the awareness among referring cardiologists improved, diagnostic delay was decreased, and patients had less severe CA at diagnosis. Further studies are warranted to assess the prognostic impact of CA clinical pathway implementation.

Heart Failure Subtypes and Cardiomyopathies in Women

Heart failure affects over 2.6 million women and 3.4 million men in the United States with known sex differences in epidemiology, management, response to treatment, and outcomes across a wide spectrum of cardiomyopathies that include peripartum cardiomyopathy, hypertrophic cardiomyopathy, stress cardiomyopathy, cardiac amyloidosis, and sarcoidosis. Some of these sex-specific considerations are driven by the cellular effects of sex hormones on the renin-angiotensin-aldosterone system, endothelial response to injury, vascular aging, and left ventricular remodeling. Other sex differences are perpetuated by implicit bias leading to undertreatment and underrepresentation in clinical trials. The goal of this narrative review is to comprehensively examine the existing literature over the last decade regarding sex differences in various heart failure syndromes from pathophysiological insights to clinical practice.

State-of-the-art review on management of end-stage heart failure in amyloidosis: transplant and beyond

Cardiac involvement occurs in light-chain (AL), transthyretin wild-type (wtATTR), and hereditary (hATTR) amyloidosis; other types of amyloidosis account for < 5% of all cardiac amyloidosis (CA). CA can present subclinically on screening, insidiously with symptoms such as exertional dyspnea, or abruptly as cardiogenic shock. Initially, CA patients were thought to be poor candidates for transplant due to short long-term survival; however, there is a marked improvement in heart and multi-organ transplant outcomes over the past 10 years with newer treatments and improvements in support with temporary and durable mechanical circulatory support while awaiting transplant. Patients with AL CA were reported to have worse post-OHT outcomes than patients with ATTR CA, but this gap is quickly closing with improved patient selection, novel chemotherapeutics, and perhaps with selected use of bone marrow transplantation. Waitlist mortality and transplantation rates have markedly improved for CA after the United Network for Organ Sharing (UNOS) policy change in October 2018. In this review, we will evaluate contemporary data from the last 5 years on advances in the field of transplantation and mechanical circulatory support in this patient population.

Applying diagnosis support systems in electronic health records to identify wild-type transthyretin amyloid cardiomyopathy risk

Aim: Wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) is frequently misdiagnosed, and delayed diagnosis is associated with substantial morbidity and mortality. At three large academic medical centers, combinations of phenotypic features were implemented in electronic health record (EHR) systems to identify patients with heart failure at risk for ATTRwt-CM. Methods: Phenotypes/phenotype combinations were selected based on strength of correlation with ATTRwt-CM versus non-amyloid heart failure; different clinical decision support and reporting approaches and data sources were evaluated on Cerner and Epic EHR platforms. Results: Multiple approaches/sources showed potential usefulness for incorporating predictive analytics into the EHR to identify at-risk patients. Conclusion: These preliminary findings may guide other medical centers in building and implementing similar systems to improve recognition of ATTRwt-CM in patients with heart failure.

Unique Phenotypes With Corresponding Pathology in Late-Onset Hereditary Transthyretin Amyloidosis of A97S vs. V30M

Objective

Hereditary transthyretin amyloidosis (ATTRv) encompasses different phenotypes among various genotypes. The analysis of the natural history and risk factors of faster progression in different genotypes would refine the treatment strategy.

Methods

The clinical manifestations of ATTRv from A97S (p.A117S) of Taiwanese and late-onset V30M (p.V50M) of Japanese were compared. An autopsy study of A97S was performed.

Results

There existed three unique features in the A97S cohort compared to the V30M cohort: (1) dysphagia, (2) carpal tunnel syndrome (CTS), and (3) onset age. First, dysphagia was common in A97S (53.4%) but not in V30M and served as a contributor to fast disease progression. All phases of swallowing were affected. In the autopsy pathology, there were extensive amyloid deposits in the viscera and nerves of the tongue, larynx, and esophagus. In A97S, 45 patients (43.3%) had a history of CTS before the onset of length-dependent symptoms by 3 years. The amyloid deposition was more prominent in the median nerve than that in the transverse carpal ligament. The onset age at different stages was younger in the A97S cohort than the V30M cohort by 4–5 years.

Conclusion

These phenotypic characteristics together with autopsy pathology in A97S are distinct from V30M. Early dysphagia in A97S correlated with fast progression. In A97S, median neuropathy leading to CTS might be in a continuous spectrum of ATTRv course rather than an independent disease entity. Such observations may serve as a foundation to explore and analyze unique phenotypes among various genotypes.

Eyes on amyloidosis: microvascular retinal dysfunction in cardiac amyloidosis

Aims

Methods and results

Conclusions

Sex-related differences in clinical presentation and all-cause mortality in patients with cardiac transthyretin amyloidosis and light chain amyloidosis

We aimed to ascertain whether sex-related differences are relevant to clinical presentation, cardiac phenotype and all-cause mortality in different types of cardiac amyloidosis, a field still poorly investigated. Medical files from consecutive patients diagnosed with cardiac amyloidosis between 2000 and 2020, at Careggi University Hospital, were retrospectively evaluated. Over this period, 259 patients (12% females) were diagnosed with wild type transthyretin amyloidosis (wtATTR), 52 (25% females) with hereditary transthyretin amyloidosis (hATTR) and 143 (47% females) with light chain amyloidosis (AL). Women with wtATTR, compared to men, were significantly older at the time of diagnosis and showed higher National Amyloidosis Centre score, thicker normalized interventricular septum, higher diastolic dysfunction and worse right ventricular function. Females with hATTR and AL had lower normalized cardiac mass compared to men, otherwise, bio-humoral parameters, NYHA class, and ECG characteristics were similar. Comparing females and male with wtATTR, hATTR and AL, no differences in Kaplan-Meier curves for all-cause mortality were observed with regard to sex, p-value >0.05. In conclusion, we did not observe major differences in clinical expression related to sex in different types of cardiac amyloidosis: specifically, all-cause mortality was not affected. Nevertheless, women with wtATTR had echocardiographic signs of more advanced disease and higher NAC score at diagnosis suggesting a possible later recognition of disease compared to men.

Cardiac amyloidosis: Description of a series of 143 cases

INTRODUCTION AND OBJECTIVES

Recently, there have been important advances in the diagnosis and treatment of cardiac amyloidosis (CA). Our aim was to provide an updated description of its 2 most frequent types: the transthyretin CA (ATTR-CA) and the light chain CA (AL-CA).

METHODS

Prospective registry of patients with CA diagnosed in 7 institutions in Galicia (Spain) between January 1, 2018 and June 30, 2020. Variables related to clinical characteristics, complementary tests, survival and causes of death were collected.

RESULTS

One hundred and forty-three patients with CA were consecutively included, 128 ATTR-CA (89.5%) and 15 AL-CA (10.5%). Mean age was 79.6±7.7 years and 23.8% were women. Most patients with ATTR-CA were diagnosed non-invasively (87.5%). On physical examination, 35.7, 35 and 7% had Popeye's sign, Dupuytren's contracture and macroglossia, respectively. Twelve-month and 24-month survival was 92.1 and 76.2% in the ATTR-CA group, and 78.6 and 61.1% in the AL-CA group (P=.152). The cause of death was cardiovascular in 80.8% of the cohort.

CONCLUSIONS

ATTR-CA can be diagnosed non-invasively in most cases and it is the most common type of CA in routine clinical practice. Furthermore, an increase in the short-term survival of CA appears to be observed, which could be due to advances related to its diagnosis and treatment.

Opportunities for Earlier Diagnosis and Treatment of Cardiac Amyloidosis

Despite the rapid expansion of noninvasive (nonbiopsy) diagnosis, contemporary patients with cardiac amyloidosis too often present with advanced features of disease, such as diminished quality of life, elevated natriuretic peptides, and advanced heart failure. Therapeutics for transthyretin cardiomyopathy (ATTR-CM) are most effective when administered before significant symptoms of cardiac dysfunction manifest, making early identification of affected individuals of paramount importance. Community engagement and ensuring that a broad range of clinicians have working knowledge of how to screen for ATTR-CM in everyday practice will be an important step in moving disease identification further upstream. However, reliance on the appropriate and timely diagnosis by individual clinicians may continue to underperform. This review highlights how targeted screening of special populations may facilitate earlier diagnosis. Systems of care that operationalize screening of high-risk subpopulations and prospective validation of novel approaches to ATTR-CM identification are needed.

Baseline Characteristics and Secondary Medication Adherence Patterns Among Patients Receiving Tafamidis Prescriptions: A Retrospective Analysis Using a National Specialty Pharmacy Dispensing Database

INTRODUCTION

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a serious, underrecognized condition, which leads to heart failure and early mortality if left untreated. Until recently, heart transplantation was the only treatment for ATTR-CM. Regulatory approval of tafamidis transformed treatment for patients. In the phase 3 Transthyretin Amyloidosis Cardiomyopathy Clinical Trial (ATTR-ACT), which established the safety and efficacy of tafamidis, medication adherence was high with 97.2% of patients taking ≥80% of scheduled doses. Evidence of real-world adherence to cardiology drugs demonstrates low adherence and suboptimal outcomes; however, real-world adherence to tafamidis has not been investigated. The main objective of this study was to describe adherence patterns of patients filling tafamidis in the Symphony Health database.

METHODS

This retrospective analysis of the Symphony Health Solutions claims database used secondary adherence measures, including modified medication possession ratio (MPRm), days between fills adherence rate, and compliance rate, to assess adherence patterns of 2020 patients filling tafamidis free acid 61-mg capsules or tafamidis meglumine 4x20-mg capsules from June 1, 2019 to August 31, 2020.

RESULTS

Patients receiving a tafamidis formulation had characteristics consistent with the expected patient population; 71.6% were aged 75-84 years, 83.2% were male, and the highest proportion resided in the Northeast region (30.5%) of the United States. Adherence for tafamidis was high, as 75% to 100% of the patients across subgroups met or exceeded the commonly defined adherence threshold of 80%. Median number of refills ordered and received was six refills per patient. Most patients received refills with no gap (n=1633) or a gap <30 days (n=1267/1317 patients). Adherence was high across follow-up time, sex, and age subgroups. Adherence varied by geographic region, with the Northeast being significantly higher than the Midwest (mean MPRm 94.41% vs 88.21%, p=0.0007).

CONCLUSION

These results provide evidence that real-world adherence to tafamidis in patients with ATTR-CM is high.

OUP accepted manuscript

Aims

In patients with transthyretin amyloid cardiomyopathy (ATTR-CM), the effect of tafamidis on myocardial function using serial speckle tracking echocardiography has not been reported. The purpose of this study was to describe the natural history of myocardial function in untreated ATTR-CM and determine the effect of tafamidis on myocardial functional parameters over 12 months of treatment.

Methods and results

A total of 45 subjects with ATTR-CM were retrospectively studied: 23 treated with tafamidis and 22 untreated. Two-dimensional speckle tracking echocardiography was analysed at baseline and 1 year. Serial longitudinal, circumferential, and radial strain, twist, torsion, and myocardial work were measured. Over 1 year, absolute global longitudinal strain (GLS) deteriorated more in the untreated group by a median of 1.1% [inter-quartile range (IQR) 0.95] compared with 0.3% (IQR 1) in the tafamidis group (P = 0.02). Myocardial work index and efficiency also deteriorated to a greater degree: 142.5 mmHg% (IQR 197) and 4% (IQR 8), respectively, in the untreated group compared with 61.5 mmHg% (IQR 210) and 1% (IQR 7) in the tafamidis group (P = 0.04). There were no significant between group differences in left ventricular ejection fraction (LVEF), tissue Doppler velocities, circumferential or radial strain, LV twist or torsion at 1 year. The stabilization effect of tafamidis on myocardial function at 1 year did not differ according to baseline GLS, LVEF, or National Amyloidosis Centre disease stage.

Conclusions

In ATTR-CM, tafamidis resulted in a lesser deterioration in GLS, myocardial work index, and efficiency over a 12-month period compared with a cohort not treated with tafamidis.

Suspecting and diagnosing transthyretin amyloid cardiomyopathy (ATTR-CM) in India: An Indian expert consensus

Transthyretin cardiac amyloidosis (ATTR-CM) is a rare and under-recognized disorder characterized by the aggregation of transthyretin-derived insoluble amyloid fibrils in the myocardium. Heterogeneity of symptoms at presentation, makes its diagnosis often delayed. An expert panel gathered on a virtual platform across India to conduct a meeting for developing a guiding tool for ATTR-CM diagnosis. The panel recommended younger age (≥40 years) for suspecting ATTR-CM and thick-walled non-dilated hypokinetic ventricle was considered as one of the important red flags. Electrocardiogram (ECG) and echocardiography (ECHO) findings were recommended as primary tests to raise the suspicion while nuclear scintigraphy and hematological tests were recommended to confirm the diagnosis and rule out amyloid light-chain (AL) amyloidosis. Cardiac magnetic resonance (CMR) and biopsy were recommended in case of ambiguity in the presence of red flags. Considering the lack of expert guidelines in the Indian scenario, a standardized diagnostic algorithm was also proposed.

Epidemiology of cardiomyopathies and incident heart failure in a population-based cohort study

AIMS

The population prevalence of cardiomyopathies and the natural history of symptomatic heart failure (HF) and arrhythmia across cardiomyopathy phenotypes is poorly understood. Study aims were to estimate the population-diagnosed prevalence of cardiomyopathies and describe the temporal relationship between a diagnosis of cardiomyopathy with HF and arrhythmia.

METHODS

People with cardiomyopathy (n=4116) were identified from linked electronic health records (~9 million individuals; 2000-2018) and categorised into hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), restrictive cardiomyopathy (RCM) and cardiac amyloidosis (CA). Cardiomyopathy point prevalence, rates of symptomatic HF and arrhythmia and timing relative to a diagnosis of cardiomyopathy were determined.

RESULTS

In 2018, DCM was the most common cardiomyopathy. DCM and HCM were twice as common among men, with the reverse trend for ARVC. Between 2010 and 2018, prevalence increased for ARVC by 180% and HCM by 9%. At diagnosis, more patients with CA (66%), DCM (56%) and RCM (62%) had pre-existing HF compared with ARVC (29%) and HCM (27%). Among those free of HF at diagnosis of cardiomyopathy, annualised HF incidence was greatest in CA and DCM. Diagnoses of all cardiomyopathies clustered around the time of HF onset.

CONCLUSIONS

The recorded prevalence of all cardiomyopathies increased over the past decade. Recognition of CA is generally preceded by HF, whereas individuals with ARVC or HCM more often developed HF after their cardiomyopathy diagnosis suggesting a more indolent course or better asymptomatic recognition. The clustering of HF and cardiomyopathy diagnoses suggests opportunities for presymptomatic or earlier diagnosis.