Screening for Cardiac Amyloidosis 5 to 15 Years After Surgery for Bilateral Carpal Tunnel Syndrome

Previous surgery for lumbar spinal stenosis and association with amyloidosis and heart failure - A Danish nationwide study

INTRODUCTION

Cardiac Amyloidosis (CA) is characterised by amyloid fibril deposits causing heart failure (HF). Lumbar spinal stenosis (LSS) is recognised as a potential red flag for CA, but the association remains underexplored in large-scale studies.

METHODS

This nationwide registry-based cohort study in Denmark included subjects ≥60 years with a history of LSS surgery. LSS patients were matched 1:1 with controls by age, sex, ischaemic heart disease, chronic obstructive lung disease, chronic kidney disease, diabetes, and atrial fibrillation.

RESULTS

A total of 44,548 LSS surgery patients and matched controls were included (median age 71.5 years, 56.2% women). The cumulative incidence of amyloidosis after 10 years was higher in the LSS group (0.16% vs. 0.08%, HR 2.29 [95% CI 1.46-3.60]) after adjustment for malignancy, hypertension, and liver disease. The cumulative incidence of HF after 10 years was 10.1% in LSS patients compared with 7.5% in controls (HR 1.28 [95% CI 1.22-1.35], p < 0.0001).

CONCLUSIONS

In this nationwide cohort study, LSS surgery was associated with a significantly higher risk of amyloidosis and HF. Prospective studies are warranted to explore the association further.

Cardiac Amyloidosis: A Narrative Review of Diagnostic Advances and Emerging Therapies

Background/Objectives: Cardiac amyloidosis (CA) is an underdiagnosed and potentially life-threatening infiltrative cardiomyopathy characterized by the extracellular deposition of misfolded amyloid fibrils in cardiac tissue. It is most commonly associated with light-chain (AL) amyloidosis and transthyretin (ATTR) amyloidosis, either hereditary or wild-type. The disease often presents with non-specific symptoms, leading to delayed diagnosis and treatment. This study aims to provide a comprehensive overview of the pathophysiology, diagnostic strategies, and current therapeutic approaches for cardiac amyloidosis, with a focus on improving early detection and clinical outcomes. Methods: A narrative review was conducted using databases such as PubMed and Scopus, covering the period from September 2016 to March 2025. Keywords such as "cardiac amyloidosis", "cardiac amyloidosis from transthyretin", "cardiomyopathy", "transthyretin", "immunoglobulin light-chain amyloidosis", and "familial amyloidosis" were used. Relevant clinical trials and guideline-based management recommendations were also included. Results: This review highlights that non-invasive imaging modalities and serum biomarker analyses are key to reducing diagnostic delays. New therapeutic developments, including gene-editing technologies and RNA-based therapies, show promise in early trials. Multidisciplinary management and increased awareness are crucial for timely diagnosis and treatment optimization. Conclusions: The early recognition of cardiac amyloidosis remains a major clinical challenge. Advances in non-invasive diagnostics and emerging disease-modifying therapies are transforming the prognosis of affected patients. Continued research and heightened clinical suspicion are essential to improve outcomes in this complex and heterogeneous disease.

Middle-ear osteolytic transthyretin amyloidosis: A CARE case report

INTRODUCTION

Wild-type transthyretin amyloidosis (ATTRwt) is a rare but serious disease that is underestimated due to asymptomatic progression. Cardiac deposits worsen prognosis, highlighting the importance of early detection for preventive treatment.

CASE REPORT

An elderly patient presented with an osteolytic lesion of the middle ear. Pathology diagnosed amyloid transthyretin deposits associated with cholesteatoma.

DISCUSSION

Identifying reliable markers to screen for risk of cardiac amyloidosis is important, due to poor prognosis. Recent studies found higher prevalence of hearing loss in ATTRwt than in the general population. The present case identified the middle ear as a target of ATTR, which could improve our understanding of the pathophysiology.

Amyloidosis Screening by Biopsy During Carpal Tunnel Release: A Systematic Review and Meta-analysis

Background

Cardiac amyloidosis (CA) is an underdiagnosed cause of heart failure with newly available effective therapies. Carpal tunnel syndrome is a common early manifestation of amyloidosis, and tissue obtained during carpal tunnel release (CTR) can be screened for amyloid, allowing for early CA diagnosis and treatment. However, neither screening criteria nor diagnostic yield are well defined. We estimated the prevalence of amyloid within the tenosynovium or transverse carpal ligament and occult CA among patients undergoing screening biopsy during CTR based on the results of published studies.

Methods

We conducted a systematic review and meta-analysis of studies that analyzed screening biopsies obtained at the time of CTR for the presence of amyloid.

Results

Of 21 articles meeting inclusion criteria, 14 included biopsies from a general population undergoing CTR, 5 reported biopsies from a prescreened population at elevated risk for amyloidosis undergoing CTR, and 2 included patients undergoing CTR with suspected amyloidosis. The pooled prevalence of amyloid within the tenosynovium/transverse carpal ligament was 11% (95% confidence interval: 5%-18%) in American and European studies without prescreening, 20% (95% confidence interval: 13%-29%) in studies of screened patients, and 88%-100% in studies of patients suspected of having amyloidosis preoperatively. Overall, 5%-20% of patients with amyloid-positive biopsies who underwent cardiac screening were eventually diagnosed with CA, of whom 33% were started on transthyretin tetramer stabilizers.

Conclusions

Biopsies for amyloid during CTR demonstrate a high rate of positivity among at-risk populations and an opportunity for early detection of occult CA. Future studies should further refine diagnostic criteria to optimize cost-effectiveness of widespread screening.

Spinal amyloid deposits are common among older patients undergoing spinal stenosis decompression surgery

Background

Recent advances in the management of transthyretin amyloid cardiomyopathy (ATTR-CM) have highlighted the need for early identification. Studies have demonstrated amyloid deposits in orthopedic surgical specimens, prompting a diagnosis of concurrent ATTR-CM. We sought to determine the prevalence of spinal amyloid deposits among patients undergoing spinal stenosis decompression surgery and whether the presence of deposits was associated with ATTR-CM.

Methods

Patients >60 years of age undergoing spinal stenosis decompression surgery were enrolled as part of a prospective, single-center, cohort study. Samples from the disc and ligamentum flavum were obtained during surgery. Patients with amyloid deposition on Congo red staining returned for standard-of-care clinical assessment consisting of blood testing, a transthoracic echocardiogram, nuclear pyrophosphate imaging when indicated, and an evaluation with a cardiologist.

Results

Out of 54 enrolled patients, 24 patients (44%; 95% CI, 31%-59%) were found to have spinal amyloid deposits. Amyloid-positive patients were older than amyloid-negative patients (70 years vs. 63 years, p < 0.01). On follow-up testing, no amyloid-positive patients were found to have definitive ATTR-CM. However, 37% of amyloid-positive patients had abnormal cardiac biomarkers, and 36% of amyloid-positive patients had reduced global longitudinal strain on echocardiography, suggesting possible early disease.

Conclusions

Spinal amyloid deposits, in both the disc and ligamentum flavum, were found in 44% of older patients undergoing spinal stenosis decompression surgery. While none of these patients tested positive for ATTR-CM on early follow-up, subtle abnormalities in cardiac testing suggest that further follow-up testing is warranted to detect the advent of cardiac amyloidosis in the future.

Transthyretin amyloid cardiomyopathy: Literature review and red-flag symptom clusters for each cardiology specialty

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) is a progressive and infiltrative cardiac disorder that may cause fatal consequences if left untreated. The estimated survival time from diagnosis is approximately 3-6 years. Because of the non-specificity of initial symptom manifestation and insufficient awareness among treating physicians, approximately one-third of patients with ATTRwt-CM are initially misdiagnosed with other cardiac diseases. Although heart failure (HF) is the most common initial manifestation of ATTRwt-CM, observed in nearly 70% of affected patients, patients may also present with other cardiologic symptoms, such as atrial fibrillation (AF) and aortic stenosis (AS). This non-specific and diverse nature of the initial ATTRwt-CM presentation indicates that various cardiology subspecialties are involved in patient diagnosis and management. Standard guideline-directed pharmacological treatment for HF is not recommended for patients with ATTRwt-CM because of its limited effectiveness. However, no established algorithms are available regarding HF management in this patient population. This literature review provides an overview of the red flags for ATTRwt-CM and research findings regarding HF management in this patient population. In addition to commonly recognized red flags for ATTRwt-CM (e.g., HF, AF and severe AS), published literature identified potential red flags such as coronary microvascular dysfunction. For HF management in patients with ATTRwt-CM, the use of mineralocorticoid receptor antagonists (MRAs) was reported as a well-tolerated option associated with a low discontinuation rate and reduced mortality. Although there is no concrete evidence for recommendations against sodium-glucose cotransporter 2 inhibitor (SGLT2i) administration, research supporting its use is limited to small-scale studies. Robust evidence is lacking for AF ablation, implantable cardioverter-defibrillators and cardiac resynchronization therapy. Based on the published findings and our clinical experience as Japanese ATTRwt-CM experts, red-flag symptom clusters for each cardiology specialty (HF, arrhythmia and ischaemia/structural heart disease) and a treatment scheme for HF management are presented. As this research area remains at an exploratory stage, our observations would require further discussion among experts worldwide.

Patient Journey to Transthyretin Cardiac Amyloidosis Diagnosis - A Japanese Claims Database Study

BACKGROUND

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an under-recognized cause of heart failure (HF) in older adults. Delayed ATTR-CM diagnosis may result in more advanced symptoms. This study describes the journey of Japanese patients with ATTR-CM.

METHODS AND RESULTS

This retrospective non-interventional study used the DeSC Healthcare database. Patients aged ≥18 years at the index date (date when ATTR-CM was first diagnosed or date of first tafamidis 80 mg prescription, whichever was earlier) and who had received ≥1 tafamidis 80 mg prescription or ≥1 specific ATTR-CM diagnosis, excepting "suspected diagnosis", at any time between April 1, 2014 and August 31, 2021 were included. The median age of patients was 79.0 years, and 79.9% (n=239) were male. The most frequently observed comorbidities defined as indicating the onset of ATTR-CM were HF (87.9%), atrial fibrillation/atrial flutter (50.2%), and conduction disorders (17.2%), with a median time from onset to index date of 15.5, 14.0, and 9.0 months for each comorbidity, respectively. Lumbar spinal stenosis (23.9%), neuropathy (13.0%), and carpal tunnel syndrome (7.5%) were common extracardiac symptoms, with a median time from the appearance of these symptoms to index date of 19.0, 5.0, and 18.0 months, respectively.

CONCLUSIONS

There was a delay between the appearance of cardiac and extracardiac comorbidities of ATTR-CM and its diagnosis in real-world Japanese clinical settings, emphasizing the need for early diagnosis of ATTR-CM.

Early diagnosis, disease stage and prognosis in wild-type transthyretin amyloid cardiomyopathy: The DIAMOND study

AIMS

Disease staging and prognostic scoring in wild-type transthyretin-related cardiac amyloidosis (ATTRwt-CA) can be captured by two systems (NAC and Columbia scores). However, uncertainty remains as epidemiology of the disease is evolving rapidly. We evaluated features associated with staging systems across ATTRwt-CA patients from different diagnostic pathways, and their association with prognosis.

METHODS

We performed an analysis on DIAMOND patients with available data to evaluate NAC and Columbia score. DIAMOND was a retrospective study from 17 Italian referral centres for CA, enrolling 1281 patients diagnosed between 2016 and 2021, and aimed at describing characteristics of pathways leading to ATTRwt-CA diagnosis. Of the original cohort, 811 patients were included in this analysis. Each patient had NAC and Columbia score calculated. Patients were grouped according to NAC and Columbia scoring classes. We described characteristics of patients according to staging classes and diagnostic pathways at diagnosis. Prevalence of early diagnoses, defined as NAC Ia, NYHA class I, no use of diuretics, no history of heart failure (HF) hospitalizations nor of atrial fibrillation prior to diagnosis, was investigated. Finally, prognostic variables were tested alone and grouped as NAC or Columbia scores in Cox univariate and multivariate regression analyses. Prognosis was investigated as all-cause mortality, in the whole population and dividing patients in HF versus other diagnostic pathways.

RESULTS

Only 1% of the study population had an early ATTRwt-CA diagnosis. Distribution of prognostic variables and of NAC and Columbia classes was heterogeneous across diagnostic pathways. The prevalence of NAC III and Columbia III was higher in the HF diagnostic pathway, but all NAC and Columbia classes were present in all pathways. Both NAC and Columbia scores were associated with all-cause mortality at univariate Cox regression analysis in the whole population, in patients from the HF diagnostic pathway and in those from other pathways. At multivariate analysis, Columbia score remained significantly associated with the outcome, together with age at diagnosis, left ventricular ejection fraction and maximal wall thickness.

CONCLUSIONS

In this contemporary nationwide cohort, an ATTRwt-CA early diagnosis was very rare. Disease staging with NAC and Columbia scoring systems determined classes of patients with heterogeneous features. Both scores were significantly associated with mortality, but other variables also had prognostic significance.

Wild-type transthyretin cardiac amyloidosis and aortic stenosis: Can carpal tunnel syndrome help distinguish the chicken from the egg?

BACKGROUND

The frequent association between transthyretin wild-type (TTRwt) cardiac amyloidosis (CA) and aortic stenosis (AS) suggests a bidirectional relationship: TTRwt-CA could induce AS and vice versa. Systemic manifestations may highlight this interaction: systemic amyloidogenesis would lead to systemic symptoms, CA, and AS, whereas the myocardial stresses induced by degenerative AS might promote local amyloidogenesis without systemic symptoms. Carpal tunnel syndrome (CTS) is the most frequently reported extracardiac symptom. Through a comparison of TTRwt-CA patients with and without CTS, we sought to determine whether CTS serves as a reliable indicator of systemic involvement and its impact on cardiac and valvular characteristics.

METHODS AND RESULTS

A total of 411 consecutive patients with TTRwt-CA were included. CTS, present in 70.3%, was associated with a younger age (80 vs. 84 years, p < 0.001), more extracardiac symptoms, and advanced CA, with greater cardiac remodeling and a higher heart-to-mediastinum ratio (1.63 vs. 1.54; p = 0.012) compared to patients without CTS. AS was present in 21% and 31% of patients with and without CTS, respectively (p = 0.024). Except for AS, these associations remained significant after adjusting for confounding factors. In severe AS, patients with CTS exclusively exhibited low-flow low-gradient (LFLG) AS and less severe class of aortic valvular calcium score (5.6% vs. 60%; p = 0.006) compared to those without CTS.

CONCLUSION

Our findings suggest that CTS may delineate two phenotypes in TTRwt-CA: a systemic phenotype associated with advanced CA and poorly calcified LFLG AS, and a cardiac phenotype characterized by less severe CA and a mixed pattern of highly calcified AS, suggesting disparate pathophysiologies.

Cardiovascular Risk Factors and Genetic Risk in Transthyretin V142I Carriers

BACKGROUND

Nearly 3% to 4% of Black individuals in the United States carry the transthyretin V142I variant, which increases their risk of heart failure. However, the role of cardiovascular (CV) risk factors (RFs) in influencing the risk of clinical outcomes among V142I variant carriers is unknown.

OBJECTIVES

This study aimed to assess the impact of CV RFs on the risk of heart failure in V142I carriers.

METHODS

This study included self-identified Black individuals without prevalent heart failure from 6 TOPMed (Trans-Omics for Precision Medicine) cohorts, the REGARDS (Reasons for Geographic And Racial Differences in Stroke) study, and the All of Us Research Program. The cohort was stratified based on the V142I genotype and the number of CV RFs (hypertension, diabetes, obesity, and hypercholesterolemia). Adjusted Cox models were used to assess the association of heart failure with the V142I genotype and CV RF profile, taking noncarriers with a favorable CV RF profile as reference.

RESULTS

The cross-sectional analysis, including 1,625 V142I carriers among 48,365 Black individuals, found that the prevalence of CV RFs did not vary by V142I carrier status. In the longitudinal analysis, there were 587 (3.2%) V142I carriers among 18,407 Black individuals (median age: 60 years [Q1-Q3: 52-68 years], 63.0% female). Among carriers, the heart failure risk was attenuated with a favorable (0 or 1 RF) CV RF profile (adjusted HR: 2.26; 95% CI: 1.58-3.23) compared with an unfavorable (3 or 4 RFs) CV RF profile (adjusted HR: 4.14; 95% CI: 2.79-6.14).

CONCLUSIONS

A favorable CV RF profile lowers but does not abrogate V142I variant-associated heart failure risk. This study highlights the importance of having a favorable CV RF profile among V142I carriers for risk reduction of heart failure.

Transthyretin Cardiac Amyloidosis in Australia and New Zealand-A Multi-Site Snapshot for 2022

OBJECTIVE

To estimate the burden of transthyretin cardiac amyloidosis (ATTR-CA) through a cross- sectional 'snapshot' of Australian Amyloidosis Network (AAN) and New Zealand (NZ) specialist amyloidosis clinics.

DESIGN, SETTING & PARTICIPANTS

A prospective survey was performed of seven AAN/ specialist amyloidosis clinics across Australia and NZ. All centres were invited to contribute data; participating centres provided clinical and demographic data for patients with ATTR-CA reviewed in the 2022 calendar year. Patients with new or previously confirmed ATTR-CA reviewed in the 2022 calendar year were included. Diagnosis was established through a positive cardiac scintigraphy scan in the absence of a monoclonal gammopathy or through a cardiac biopsy staining positive with transthyretin (TTR).

RESULTS

A total of 515 patients were reviewed across seven sites. A total of 302/515 (59%) were wild type TTR (ATTRwt), 63/515 (12%) were variant ATTR (ATTRv) and the remaining 150 (29%) had not undergone genetic testing at the time of data collection. A total of 455/515 (88%) patients were male. Compared to ATTRwt, patients with ATTRv had smaller left ventricular (LV) wall thickness (IVSd 14±3 mm vs 16±3mm, p<0.001), and better LV systolic function (LVGLS -15.4±5% vs -11.7±3%, p<0.001). Most patients, 387/515 (75%) were on at least one ATTR specific treatment, including EGCG (157), diflunisal (139), doxycycline (68) and tafamidis (78), acoramidis (33) and gene silencer therapies or monoclonal antibodies (23).

CONCLUSION

A significant number of patients with ATTR-CA are seen in specialist amyloidosis clinics across Australia and NZ. Most patients received specific amyloidosis therapy, thorough enrollment in clinical trials. With increased recognition of amyloidosis and newer therapies becoming available, the volume of patients seen in these clinics is likely to increase.

Biomarkers to Predict Abnormal Technetium-99m Pyrophosphate Scans in Patients With Suspected Transthyretin Amyloidosis

Background

Technetium Tc 99m pyrophosphate scintigraphy (99mTc PYP imaging) is a diagnostic tool for transthyretin amyloid cardiomyopathy (ATTR-CM). Cardiac biomarkers, particularly high-sensitivity cardiac troponin (hs-cTn) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), may help identify patients at low or high risk for ATTR-CM.

Objectives

The authors sought to evaluate the predictive value of hs-cTnT and NT-proBNP in patients undergoing 99mTc PYP imaging for suspected ATTR-CM in a large U.S. cohort.

Methods

This was a retrospective study of patients who underwent 99mTc PYP imaging between May 2013 and September 2022, including those with at least 1 hs-cTnT measurement within 6 months of the scan.

Results

ATTR-CM was diagnosed in 427 of 1,442 patients (29.6%). A hs-cTnT level <6 ng/L (n = 50, 3.5%) showed a negative predictive value of 100% (95% CI: 93%-100%) and sensitivity of 100% (95% CI: 99%-100%) for ruling out ATTR-CM. As the hs-cTnT threshold increased, the number of patients who could be ruled out also increased, but false negatives emerged. The positive predictive value for ruling in ATTR-CM remained low. NT-proBNP showed similar results (n = 1,378). The combination of hs-cTnT <14 ng/L and NT-proBNP <60 ng/L identified 45 patients (3.3%) without ATTR-CM.

Conclusions

In patients undergoing 99mTc PYP imaging for suspected ATTR-CM, very low hs-cTnT levels can effectively rule out the diagnosis, although in a small subset of patients. Higher thresholds increase the risk of false negatives. NT-proBNP and combined biomarker strategies showed similar trends, the utility of hs-cTnT and NT-proBNP for ruling in the disease is limited.

Performance of Clinical Scoring Systems in the Diagnosis of Transthyretin Amyloid Cardiomyopathy in a Diverse Patient Cohort

BACKGROUND

Two diagnostic clinical scoring systems, the ATTR-CM Score and the T-AMYLO Score, have been proposed but not validated in diverse populations despite Black race being an important risk factor for transthyretin amyloid cardiomyopathy (ATTR-CM). The aim of this study was to evaluate their performance in diagnosing ATTR-CM in a diverse patient cohort.

METHODS

This retrospective single-center study analyzed patients who underwent a 99mTc-pyrophosphate single-photon emission computed tomography scan (Tc-PYP) for workup of suspected ATTR-CM. ATTR-CM was considered present in those exhibiting Perugini scores of 2 or 3, confirmed by myocardial radiotracer uptake via single-photon emission computed tomography. The diagnostic performance of a multivariate regression model and the two scoring systems was tested against Tc-PYP as the gold standard.

RESULTS

Our cohort included 476 patients, of which 308 (65%) were non-Hispanic Black, 93 (20%) were Hispanic, and 215 (45%) were female. A total of 164 (34%) had a positive Tc-PYP result. Age ≥74 years, male sex, history of carpal tunnel, left ventricular ejection fraction <55%, posterior wall thickness over 12 mm, and relative wall thickness over 0.57 were independent predictors of positive Tc-PYP results in our cohort, and hemoglobin level <10 mg/dL, glomerular filtration rate <30 mL/min/1.73 m2, and coronary artery disease were independent predictors of negative Tc-PYP. The multivariate model had an area under the curve (AUC) of 0.92 (95% CI 0.90-0.95). The ATTR-CM Score (AUC, 0.86; 95% CI 0.83-0.90) had better diagnostic accuracy than the T-AMYLO Score (AUC, 0.75; 95% CI 0.71-0.80; P < .001).

CONCLUSIONS

Two simple clinical scoring systems, derived to identify patients at high risk of having ATTR-CM necessitating further diagnostic evaluation, showed good predictive accuracy in our diverse patient cohort. The ATTR-CM Score was superior to the T-AMYLO Score in our cohort.

Prevalence of transthyretin cardiac amyloidosis in patients with aortic stenosis

BACKGROUND

Transthyretin cardiac amyloidosis (ATTRCA) is a prevalent disease, and it can be associated with heart failure (HF), left ventricle hypertrophy (LVH), atrial fibrillation (AF), and aortic stenosis (AS).

AIM

The study aims to detect the prevalence of ATTRCA in the symptomatic AS population.

METHOD

A single-center prospective study screening for ATTRCA in patients diagnosed with symptomatic severe AS undergoing aortic valve (AV) intervention.

RESULTS

A total of 27 patients were enrolled, of which 15 (56%) were men. The mean age was 72.8 ± 10.5 years. HF symptoms were present in 11 (40.7%) patients at New York Heart Association (NYHA) class II, while 15 (55.6%) patients had NYHA class III symptoms. AF was present in 6 (22.2%) patients. The mean left ventricle ejection fraction (LVEF) was 49.4 ± 9.75%, and the mean stroke volume (SV) was 37.4 ± 8.7 ml/m2. The interventricular septal thickness (IVS) was 1.2 ± 0.18 cm. The AS mean gradient was 46 ± 12 mmHg, and the aortic valve area (AVA) was 0.69 ± 0.16 cm2. The ATTRCA was diagnosed by bone scintigraphy in 5 (18.5%) AS patients. Perugini scores of 2 and 3 were considered positive for ATTRCA with the heart/contralateral lung (H/CL) ratio of 1.48 ± 0.35. There was no difference in LVEF between patients with ATTRCA and those without ATTRCA 50 ± 9.8% vs 47 ± 9.3%; p-value 0.55. The ATTRCA had a lower SV of 33.9 ± 6.9 ml/m2 compared to patients without ATTRCA 37.5 ± 8.8 ml/m2; p-value of 0.34. There was no significant difference in LVH or IVS thickness between the patients with ATTRCA and those without ATTRCA. The left ventricle (LV) mass index in ATTRCA was 87 ± 21 g/m2 compared to patients without ATTRCA 98.7 ± 26 g/m2, with a p-value 0.38, and the IVS thickness was 1.1 ± 0.22 cm compared to patients without ATTRCA 1.2 ± 0.18 cm; p-value 0.17. The left atrial (LA) volumes were significantly higher in the ATTRCA group 55.5 ± 25.6 ml/m2 compared to patients without ATTRCA 37.5 ± 10.9 ml/m2 with a significant p-value 0.028. The mean AV gradient was lower in ATTRCA patients at 40.8 ± 8.4 mmHg, compared to patients without ATTRCA at 46.1 ± 12.1 mmHg; it did not reach a statistical significance p-value 0.3. There was a significant difference in LV relative longitudinal strain (LS) between patients with ATTRCA 11.8 ± 3.2 and those without ATTRCA 63.3 ± 22.6 with a significant p-value 0.001.

CONCLUSION

ATTRCA is prevalent in AS patients; bone scintigraphy is recommended for screening AS patients for ATTRCA.

Amyloid nomenclature 2024: update, novel proteins, and recommendations by the International Society of Amyloidosis (ISA) Nomenclature Committee

The ISA Nomenclature Committee met at the XIX International Symposium of Amyloidosis in Rochester, MN, 27 May 2024. The in-person event was followed by many electronic discussions, resulting in the current updated recommendations. The general nomenclature principles are unchanged. The total number of human amyloid fibril proteins is now 42 of which 19 are associated with systemic deposition, while 4 occur with either localised or systemic deposits. Most systemic amyloidoses are caused by the presence of protein variants which promote misfolding. However, in the cases of AA and ATTR the deposits most commonly consist of wild-type proteins and/or their fragments. One peptide drug, previously reported to create local iatrogenic amyloid deposits at its injection site, has been shown to induce rare instances of systemic deposition. The number of described animal amyloid fibril proteins is now 16, 2 of which are unknown in humans. Recognition of the importance of intracellular protein aggregates, which may have amyloid or amyloid-like properties, in many neurodegenerative diseases is rapidly increasing and their significance is discussed.

Carpal Tunnel Syndrome as a Potential Indicator of Cardiac Amyloidosis: A Systematic Review and Meta-Analysis

Carpal tunnel syndrome (CTS) and cardiac amyloidosis (CA) are seemingly disparate medical conditions but may be linked. CTS can be a sign of early CA, and CA can be a hidden cause of heart failure. Therefore, in this systematic review and meta-analysis, we aim to investigate the expected correlation between the occurrence of CTS and CA. A comprehensive search was conducted across multiple databases, including PubMed, Web of Science, Scopus, and Cochrane Library, to get relevant studies previously published before June 2023. No language restrictions were applied. Randomized clinical trials and observational studies have been included to investigate the proportion of patients reporting CA among patients with an established diagnosis of CA, and also the incidence of patients who have CTS among patients with CA has been investigated with a pooled estimation of the expected time from the diagnosis of CTS till the development of CA. Studies that did not report data on CTS or CA or lacked sufficient details were excluded. Meta-analysis of data for each outcome was performed using R version R.4.3.2 software (R Foundation for Statistical Computing, Vienna, Austria) using the Meta package. Heterogeneity across studies was assessed using the I² statistic. A meta-analysis of 15 studies, including 1416 patients, evaluated the relationship between CTS and CA. Among these, 495 patients with CTS were assessed for the presence of CA, and 915 patients with CA were evaluated for the presence of CTS. The pooled meta-analysis of eight studies, which included 915 patients with CA, revealed that 38% (95% CI: 35%-41%) had a history of CTS. Conversely, the proportion of patients with CTS who developed CA was 13% (95% CI: 4%-35%). The pooled mean time from CTS to the development of CA, based on 639 patients across four studies, was 6.02 years (95% CI: 3.76-8.36). Significant heterogeneity was noted for some outcomes (e.g., proportion of CA in patients with CTS: I²=93%), likely influenced by variations in study populations, age distributions, and diagnostic criteria. Our review of the literature suggests that there may be a link between CTS and CA. However, more research is needed to confirm this link and to understand how the two conditions are related. It is important to consider the possibility of CA in patients with CTS, as screening, early detection, and timely treatment can improve outcomes by slowing disease progression and reducing complications.

Value of troponin and NT-proBNP to screen for cardiac amyloidosis after carpal tunnel syndrome surgery

BACKGROUND

Early diagnosis of cardiac amyloidosis (CA) is crucial due to the promising effect of disease-modifying treatment. This calls for screening strategies to identify CA patients with so-called "red flags", such as carpal tunnel syndrome (CTS).

OBJECTIVES

This study aims to assess Troponin-T (TnT) and N-terminal pro-B-type natriuretic peptide (NT-ProBNP) as predictors for CA in patients with a history of surgery for bilateral carpal tunnel syndrome, a population suitable for systematic screening.

METHODS

Subjects with a history of surgery for bilateral CTS 5-15 years prior, identified using national registries were investigated for CA as per international recommendations. Sensitivity, specificity, positive and negative predictive values were assessed, and receiver operating curves were generated using logistic regression.

RESULTS

Among the 250 participants, 12 were diagnosed with CA, all with wild-type transthyretin amyloidosis. Elevated TnT levels (≥13 ng/L) were found in all CA patients and 25.6% (±2.8) of non-CA patients. The negative predictive value (NPV) of TnT <13 ng/L was 100%. For NT-ProBNP the NPV was 99.1% when age dependent cutoff levels were used. A combination of both biomarkers yielded an NPV of 99.1% and sensitivity of 99.7%. Early disease (Mayo or NAC stage 1) was found in 83% of identified patients with CA.

CONCLUSION

This study demonstrates the utility of TnT and NT-ProBNP as negative predictors to exclude CA in a screening population with a history of surgery for CTS.

The journey to diagnosis of wild-type transthyretin-mediated (ATTRwt) amyloidosis: a path with multisystem involvement

BACKGROUND

Wild-type and hereditary transthyretin-mediated amyloidosis (ATTRwt and ATTRv amyloidosis, respectively) are progressive, fatal diseases with a broad range of clinical presentations and multisystem effects. Despite having a higher prevalence, ATTRwt amyloidosis is less well characterized due to its non-hereditary nature, and its relatively poorer disease awareness delays diagnosis. Understanding of its natural history has evolved in recent years, but this is largely based on physician-collected data rather than patients' reports of their own experiences. A mixed methods approach was used to evaluate how the healthcare journeys of patients with ATTRv and ATTRwt amyloidosis compare.

METHODS

A quantitative survey was administered to US-patients diagnosed with both ATTRwt amyloidosis and ATTRv amyloidosis identified through a patient support group. Subsequent in-depth interviews with participants with ATTRwt amyloidosis were conducted. Quantitative data with related qualitative quotes from patients were produced to characterize their paths to diagnosis and the disease burden experienced.

RESULTS

A total of 47 respondents completed the survey (ATTRv, n = 20 and ATTRwt, n = 27) and a total of 14 survey respondents with ATTRwt amyloidosis were interviewed. Survey results reported a high disease burden for patients with both conditions, with patients with ATTRwt amyloidosis reporting more diagnoses and procedures prior to their final diagnosis. Interviews with participants with ATTRwt amyloidosis revealed that patients face a high symptomatic burden of disease. Diagnosis was often delayed due to three key factors: (1) early signs of ATTRwt amyloidosis were often assumed to be related to old age; (2) many medical specialists working in silos were involved in participants' diagnostic; and (3) there was a general lack of disease awareness. Early indicators such as carpal tunnel syndrome were often overlooked. Participants were typically diagnosed after the disease had progressed to include severe cardiac symptoms such as atrial fibrillation and severe shortness of breath. Sleep apnoea was also reported by a number of participants, with a considerable impact on quality of life.

CONCLUSIONS

Our study provides insight into the overall impact of the patient journey on their quality of life and demonstrates how increased awareness of ATTRwt amyloidosis and more coordinated engagement with physicians could reduce the time to diagnosis.

Epidemiology, diagnosis, and management of cardiac amyloidosis

Cardiac amyloidosis (CA) is an infiltrative restrictive cardiomyopathy caused by the deposition of amyloid fibrils in the myocardium. It manifests in two primary subtypes: transthyretin cardiac amyloidosis (ATTR) and immunoglobulin light chain cardiac amyloidosis (AL). ATTR is further classified into wild-type and hereditary based on transthyretin gene mutation. Advances in diagnostics and therapeutics have transformed CA from a rare and untreatable condition to a more prevalent and manageable disease. Noninvasive diagnostic tools such as electrocardiography, echocardiography, and cardiac magnetic resonance can raise suspicion for CA; bone scintigraphy can non-invasively confirm ATTR, while AL necessitates histological confirmation. The severity of ATTR and AL can be assessed through serum biomarker-based staging. Treatment approaches differ, ranging from silencing or stabilizing transthyretin and degrading amyloid fibrils in ATTR to employing anti-plasma cell therapies and autologous stem cell transplantation in AL.

Assessment of transthyretin instability in patients with wild-type transthyretin amyloid cardiomyopathy

The pathophysiology of variant transthyretin (TTR) amyloidosis (ATTRv) is associated with destabilizing mutations in the TTR tetramer. However, why TTR with a wild-type genetic sequence misfolds and aggregates in wild-type transthyretin amyloidosis (ATTRwt) is unknown. Here, we evaluate kinetic TTR stability with a newly developed ELISA system in combination with urea-induced protein denaturation. Compared with that in control patients, endogenous TTR in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) exhibited thermodynamic instability, indicating that circulating TTR instability may be associated with the pathogenesis of ATTRwt as well as ATTRv. Our findings provide new insight into the underlying mechanisms of ATTRwt.

Radionuclide Imaging of Cardiac Amyloidosis: An Update and Future Aspects

Cardiac amyloidosis (CA) is caused by the misfolding, accumulation and aggregation of proteins into large fibrils in the extracellular compartment of the myocardium, leading to restrictive cardiomyopathy, heart failure and death. The major forms are transthyretin (ATTR) CA and light-chain (AL) CA, based on the respective precursor protein. Each of them requires early diagnosis for a timely treatment initiation that will improve patient outcomes. For this, radionuclide imaging is essentially used as single-photon emission computed tomography (SPECT) with bone-avid radiotracers or as positron emission tomography (PET) with amyloid-binding radiotracers. Both offer unprecedented specificity for the diagnostic of CA. SPECT has even revolutionized the diagnosis of ATTR-CA by making it non-invasive. Indeed, SPECT has now entered the standard diagnostic pathway to CA and has led to earlier diagnosis of the disease. SPECT also modified the epidemiology of ATTR-CA, highlighting that the disease is much more frequent than previously believed, and showing that ATTR-CA plays a substantial role in HFpEF and aortic stenosis, particularly among elderly patients. In parallel, amyloid-binding radiotracers for PET have accumulated a substantial amount of evidence, but are not approved for clinical use in CA yet. Further studies are needed to refine acquisition protocols and validate results in broader populations. Unlike bone-avid SPECT radiotracers, PET radiotracers have been specifically created to bind to amyloid fibrils. Thus, PET is the only imaging method that is truly specific for amyloid deposits and very sensitive to any amyloid type. Indeed, PET can not only detect ATTR-CA, but also AL-CA and rare hereditary forms. For both SPECT and PET, advances in quantitation of myocardial uptake have generated more granular and reproducible findings, paving the way for progress in earlier diagnosis, risk stratification and therapeutic response monitoring. Encouraging findings have shown that SPECT and PET are sensitive to early CA when other diagnostic methods are negative. Both radionuclide imaging techniques can predict adverse outcomes, but more evidence is needed to determine how to use them in conjunction with usual prognostic staging scores. Studies on follow-up imaging after therapy suggested that SPECT and PET can capture myocardial changes in CA, but again, more data are needed to meaningfully interpret such changes. Based on all these promising results, radionuclide imaging has the potential to further impact the landscape of CA in diagnosis, prognosis and follow-up, but also to substantially contribute to the assessment of novel therapies that will improve the lives of patients with CA.

Early Diagnosis of Amyloidosis and Cardiac Involvement through Carpal Tunnel Surgery and Predictive Factors

Background/Objectives: To determine the prevalence of amyloidosis through the analysis of synovial tissue and transverse carpal ligament (TCL) in patients undergoing surgery for carpal tunnel syndrome (CTS), detect predictive factors for the presence of amyloid, and assess cardiac involvement degree. Methods: A prospective study with longitudinal cohort follow-up at a teaching hospital. Patients undergoing CTS surgery from 1 January 2019 to 31 May 2021 were included. Samples from synovial and TCL tissues were examined for amyloid presence. Multivariate analysis was used to detect predictive factors of the presence of amyloid. Patients with amyloid underwent echocardiography, laboratory analyses, and scintigraphy. Results: Two hundred and forty-six patients were included. The prevalence of amyloid was 11.4% in TCL and 12.6% in synovial tissues. Age (p = 0.035; OR 1.123), bilateral CTS symptoms (p = 0.022; OR 3.647), and trigger finger (p < 0.001; OR 3.537) were predictors of the presence of amyloid. Seventeen patients were diagnosed with transthyretin amyloidosis (ATTR) located in the carpus (no scintigraphic cardiac uptake or grade 0), one with light chain amyloidosis, eight with ATTR with cardiac involvement (grades 2-3), and five with ATTR in the carpus and scintigraphic uptake grade 1 (with normal echocardiogram and blood and urine tests). Conclusions: We detected amyloid in 12.6% of unselected consecutive patients who underwent CTS surgery. Biopsy in patients with CTS for amyloid detection, especially in elderly patients with bilateral symptoms and trigger finger, may be useful for the early diagnosis of amyloidosis, primarily due to transthyretin.

Screening for cardiac amyloidosis in patients with tenosynovial red flags: A collaboration between family medicine and cardiology

BACKGROUND

Amyloid deposition in tenosynovial structures precedes cardiac involvement up to 20 years. Therefore, a cardiological screening in patients with a history of tenosynovial manifestations of cardiac amyloidosis (CA) could lead to an increased number of early diagnoses.

METHODS

Patients with tenosynovial manifestations of CA (carpal tunnel syndrome, atraumatic biceps tendon rupture, lumbar spinal stenosis) have been identified by general practitioners and evaluated in a Referral Center for CA. Patients with a high suspicion of CA underwent the CA diagnostic pathway.

RESULTS

Among 50 General Practitioners (GP) contacted, 10 (20%) agreed to participate in the study for a total of 5615 patients ≥60 years. One hundred forty-five patients met the inclusion criteria, 2 of them already had a diagnosis of CA, and 57 agreed to undergo a cardiological evaluation (electrocardiography, echocardiography, NTproBNP assay). The median age was 73 [67-80] years and 31 (54%) were women. Eight patients were suggested to start the CA diagnostic pathway, five of them underwent a complete diagnostic evaluation for CA, three refused to complete the diagnostic exams and no new diagnoses were made.

CONCLUSION

A screening program for CA in patients with tenosynovial manifestations identified by general practitioners is feasible, but may not yield a high rate of new diagnosis. In this study, we identified two patients who already had a diagnosis of CA, and among patients at high risk for CA, 37% refused to complete the diagnostic pathway. Increased awareness of CA among patients might increase participation and diagnostic yield in screening studies. Further validation of this protocol is needed to evaluate its diagnostic performance.

Diagnostic Modalities in the Detection of Cardiac Amyloidosis

Cardiac amyloidosis (CA) results mainly from the infiltration of the myocardium by either immunoglobulin light-chain fibrils (AL) or transthyretin fibrils (ATTR), causing restrictive cardiomyopathy and eventually death if untreated. AL derives from monoclonal immunoglobulin light chains produced by plasma cell clones in the bone marrow, while ATTR is the misfolded form of hepatically derived transthyretin (TTR) protein and can be hereditary (ATTRv) or wild-type (ATTRwt). Over the last decade, improvements in diagnostic imaging and better clinical awareness have unleashed a notable presence of CA in the community, especially ATTR in the elderly population. These multimodality imaging modalities include echocardiography, cardiac magnetic resonance, and radionuclide scintigraphy with bone-avid tracers. There has been remarkable progress in the therapeutic landscape as well, and there are disease-modifying therapies available now that can alter the course of the disease and improve survival if initiated at an early stage of the disease. There remains an unmet need for detecting this disease accurately and early so that these patients can benefit the most from newly emerging therapies.

Carpal Tunnel Syndrome and Transthyretin Amyloidosis in the All of Us Research Program

OBJECTIVE

To evaluate the association of carpal tunnel syndrome (CTS) with incident heart failure and incident amyloidosis and to assess the risk of CTS in pathogenic TTR genetic variant carriers.

METHODS

This prospective cohort study included multiethnic US adults 18 years of age and older without prevalent heart failure and amyloidosis with available genotypic data from the All of Us Research Program. The primary outcomes were incident heart failure and incident amyloidosis. The association of incident heart failure and incident amyloidosis with CTS was assessed using multivariable adjusted Cox models accounting for age, sex, race and ethnicity, obesity, hypertension, diabetes, statin use, and smoking status.

RESULTS

Of the 166,987 individuals included, the median age was 54 (38 to 66) years; 105,279 (63.0%) were female, and 92,780 (55.6%) were non-Hispanic White individuals; CTS was identified in 12,407 (7.4%) individuals. Compared with individuals without CTS, the adjusted hazard ratio for incident heart failure was 1.13 (95% CI, 1.02 to 1.26) in individuals with CTS. The risk of amyloidosis was ∼3-fold higher (adjusted hazard ratio, 2.86; 95% CI, 1.71 to 4.77) in individuals with CTS compared with those without CTS. Individuals carrying a pathogenic TTR variant had an approximately 40% higher risk (adjusted hazard ratio, 1.38; 95% CI, 1.16 to 1.65) for development of CTS compared with noncarriers.

CONCLUSION

Cardiac amyloidosis screening programs may use CTS as a sentinel event and use genetic testing to identify individuals at a higher risk of TTR amyloidosis.

Cardiac amyloidosis at a glance

Amyloidosis can affect any organ in the body by deposition of amyloid fibrils. When these aggregate in the heart, it leads to cardiac amyloidosis a life-threatening and progressive disease. Although considered a rare condition, advances in imaging techniques and raised awareness have shown that it might be more frequent than has been historically estimated. Cardiac amyloidosis can be hereditary or occur as a consequence of the ageing process but, regardless of type, patients experience a heavy symptomatic burden. This article provides an overview of its pathophysiology, signs and symptoms and how any nurse can look for the main red flags in clinical practice. Early referral for specialist care can have a significant impact on disease progression and patient quality of life.

Breakthrough advances enhancing care in ATTR amyloid cardiomyopathy

Transthyretin amyloid cardiomyopathy (ATTR-CM) has been traditionally considered a rare and inexorably fatal condition. ATTR-CM now is an increasingly recognized cause of heart failure (HF) and mortality worldwide with effective pharmacological treatments. Advances in non-invasive diagnosis, coupled with the development of effective treatments, have transformed the diagnosis of ATTR-CM, which is now possible without recourse to endomyocardial biopsy in ≈70 % of cases. Many patients are now diagnosed at an earlier stage. Echocardiography and cardiac magnetic resonance have enabled identification of patients with possible ATTR-CM and more accurate prognostic stratification. Although radionuclide scintigraphy with 'bone' tracers has an established diagnostic value, the diagnostic performance of the bone tracers validated for non-invasive confirmation of ATTR-CM may not be equal. Characterising the wider clinical phenotype of patients with ATTR-CM has enabled identification of features with potential for earlier diagnosis such as carpal tunnel syndrome. Therapies able to slow or halt ATTR-CM progression and increase survival are now available and there is also evidence that patients may benefit from specific conventional HF medications. Cutting-edge research in the field of antibody-mediated removal of ATTR deposits compellingly suggest that ATTR-CM is a truly reversible disorder, bringing hope for patients even with advanced disease. A wide horizon of possibilities is unfolding and awaits discovery.

Hospitalization-based epidemiology of systemic and cardiac amyloidosis in the Veneto Region, Italy

AIM

Defining the epidemiology of systemic and cardiac amyloidosis (CA) is a contemporary challenge. The present study aimed to estimate incidence and time trends in amyloidosis-related hospitalizations (AH) in Veneto Region (5 million inhabitants, Northeastern Italy).

METHODS

International Classification of Diseases (ICD-9) codes were used to identify AH in Veneto from 2010 to 2020. AH were defined as any hospitalization with a discharge summary reporting an ICD-9 code for systemic amyloidosis. Hospitalization for CA was defined as records with ICD-9 code for systemic amyloidosis and ICD-9 code for heart failure,cardiomyopathy or arrhythmia. Hospital/outpatient encounters for carpal tunnel syndrome (CTS) surgeries also were extracted. AH incidence was estimated using a buffer of 5 years.

RESULTS

In the time range 2015-2020, the incidence rate of AH was 23.5 cases per 106 (95% confidence interval, CI, 21.8; 25.3), mainly affecting patients>65 years (76.2%) and males (63.5%), with a progressively increasing trend (percent annual increase 17%, 95% CI 12; 22%). The 10 year prevalence of AH in 2020 was 124.5 per 106 (95% CI 114.9; 134.8). In 2020, annual hospitalized prevalent cases of CA were about 70% of all cases (159/228), mainly patients >65 years and males. Among patients with multiple CTS surgeries, a subsequent code for cardiac disease was found in 913 after a median of 3.9 years, more frequently in men than in women (463/6.526 7.1% versus 450/11.406 3.9%).

CONCLUSIONS

In Veneto, we recorded a significantly increasing trend in the incidence of AH, with concordant increasing prevalence estimates.

Being a Better Starfish Thrower, Carpal Tunnel Syndrome, and Cardiac Amyloidosis: The Hand Surgeon's Opportunity to Make a Profound Difference

In recent years, there is increasing literature in cardiac and hand surgery journals demonstrating a stronger association between seemingly idiopathic carpal tunnel and amyloidosis. Despite this, it can be difficult for hand surgeons to identify who need biopsies, and this is further complicated by the cost of a biopsy and the low likelihood that a patient has cardiac amyloidosis. In patients with cardiac amyloidosis and carpal tunnel syndrome (CTS), CTS is typically diagnosed 5-10 years prior. Early diagnosis of cardiac amyloidosis is crucial, as current medications work to slow disease progression, but do not treat existing amyloid deposits. Hand surgeons can play an essential role in early diagnosis. The patient case discussed describes a man who had a carpal tunnel biopsy because of his bilateral CTS, recurrent trigger fingers, and his age. After confirmation of amyloidosis, he was referred for cardiac amyloidosis evaluation. Testing confirmed this diagnosis, and he was started on tafamidis, which studies show provide patients an opportunity for increased survival and quality of life. The responsibility falls on cardiologists and hand surgeons to continue refining the indications for carpal tunnel biopsy and spreading awareness of carpal tunnel biopsy and amyloid testing, as much work is still needed.

Cardiac Amyloidosis Due to Transthyretin Protein: A Review

Importance

Systemic amyloidosis from transthyretin (ATTR) protein is the most common type of amyloidosis that causes cardiomyopathy.

Observations

Transthyretin (TTR) protein transports thyroxine (thyroid hormone) and retinol (vitamin A) and is synthesized predominantly by the liver. When the TTR protein misfolds, it can form amyloid fibrils that deposit in the heart causing heart failure, heart conduction block, or arrhythmia such as atrial fibrillation. The biological processes by which amyloid fibrils form are incompletely understood but are associated with aging and, in some patients, affected by inherited variants in the TTR genetic sequence. ATTR amyloidosis results from misfolded TTR protein deposition. ATTR can occur in association with normal TTR genetic sequence (wild-type ATTR) or with abnormal TTR genetic sequence (variant ATTR). Wild-type ATTR primarily manifests as cardiomyopathy while ATTR due to a genetic variant manifests as cardiomyopathy and/or polyneuropathy. Approximately 50 000 to 150 000 people in the US have heart failure due to ATTR amyloidosis. Without treatment, heart failure due to ATTR amyloidosis is associated with a median survival of approximately 5 years. More than 130 different inherited genetic variants in TTR exist. The most common genetic variant is Val122Ile (pV142I), an allele with an origin in West African countries, that is present in 3.4% of African American individuals in the US or approximately 1.5 million persons. The diagnosis can be made using serum free light chain assay and immunofixation electrophoresis to exclude light chain amyloidosis combined with cardiac nuclear scintigraphy to detect radiotracer uptake in a pattern consistent with amyloidosis. Loop diuretics, such as furosemide, torsemide, and bumetanide, are the primary treatment for fluid overload and symptomatic relief of patients with ATTR heart failure. An ATTR-directed therapy that inhibited misfolding of the TTR protein (tafamidis, a protein stabilizer), compared with placebo, reduced mortality from 42.9% to 29.5%, reduced hospitalizations from 0.7/year to 0.48/year, and was most effective when administered early in disease course.

Conclusions and Relevance

ATTR amyloidosis causes cardiomyopathy in up to approximately 150 000 people in the US and tafamidis is the only currently approved therapy. Tafamidis slowed progression of ATTR amyloidosis and improved survival and prevented hospitalization, compared with placebo, in people with ATTR-associated cardiomyopathy.

Amyloidosis and Considerations for the Hand Surgeon

Amyloidosis can lead to cardiac, renal, and other multiorgan failure. New treatments have become available that can prolong survival but rely on early diagnosis. Manifestations of amyloidosis in hand surgery include carpal tunnel syndrome, trigger finger, peripheral neuropathy, and spontaneous distal biceps rupture. Often, these can predate systemic amyloidosis, offering hand surgeons an opportunity to diagnose patients with amyloidosis before systemic disease, refer them for treatment, and potentially alter disease course and prolong survival. In this review, we describe the pathophysiology and two most common subtypes of amyloidosis seen by hand surgeons. We provide guidance on biopsy practices and referral for patients with amyloidosis. Lastly, we provide a brief overview of the treatments for amyloidosis and their effect on disease course.

Neuromuscular manifestations of wild type transthyretin amyloidosis: a review and single center's experience

Transthyretin amyloidosis (ATTR) is a condition defined by accumulation of insoluble transthyretin amyloid deposits in multiple organs, especially in the peripheral nerve and heart muscle. ATTR may result from transthyretin mutations (variant ATTR or ATTRv) or may occur with normal transthyretin genotype (wild type ATTR or ATTRwt). ATTRwt was previously known as "senile amyloidosis" and causes cardiomyopathy which may lead to heart failure with a preserved ejection fraction, affecting predominantly elderly men. The exact prevalence of ATTRwt in the general population remains unclear, but its occurrence may be underestimated in women. It was observed that a proportion of ATTRwt cardiomyopathy patients may develop slowly progressing neuropathy that is milder and indolent in comparison with typical progressive neuropathy associated with ATTRv. Furthermore, the causality of neuropathy is often uncertain in patients with ATTRwt. Neuropathy symptoms, including distal sensory loss, unsteadiness and (neuropathic) pain are common in elderly patients with multiple potential causes, and as ATTRwt patients are typically older, relatively high prevalence of peripheral neuropathy is expected with frequent comorbidities. Relatively high prevalence of ATTRwt in elderly population contrasts few documented cases of neuropathy caused by ATTRwt, and there is uncertainty whether ATTRwt neuropathy is an infrequent occurrence or a significant manifestation of multisystemic ATTRwt. We review neurologic and musculoskeletal manifestations of ATTRwt and present clinical features of a single center cohort of ATTRwt patients with suspected peripheral neuropathy.

What's new in cardiac amyloidosis? Pharmacological treatment, physical activity, and care of patients with transthyretin cardiac amyloidosis

Awareness, proper diagnosis and treatment of cardiac amyloidosis have increased, but there are still several unmet needs that have to be addressed for the optimal care of the disease. In this comprehensive review, we describe current and future treatments for both hereditary and wild-type TTR cardiac amyloidosis and also review lifestyle, including current challenges and opportunities for specific dietary concerns and exercise sports for these patients.

Prevalence of amyloid in ligamentum flavum of patients with lumbar spinal stenosis

BACKGROUND

Transthyretin (ATTR) amyloidosis is often diagnosed in an advanced stage, when irreversible cardiac damage has occurred. Lumbar spinal stenosis (LSS) may precede cardiac ATTR amyloidosis by many years, offering the opportunity to detect ATTR already at the time of LSS surgery. We prospectively assessed the prevalence of ATTR in the ligamentum flavum by tissue biopsy in patients aged >50 years undergoing surgery for LSS.

METHODS

Ligamentum flavum thickness was assessed pre-operatively on axial T2 magnetic resonance imaging (MRI) slices. Tissue samples from ligamentum flavum were screened centrally by Congo red staining and immunohistochemistry (IHC).

RESULTS

Amyloid in the ligamentum flavum was detected in 74/94 patients (78.7%). IHC revealed ATTR in 61 (64.9%), whereas amyloid subtyping was inconclusive in 13 (13.8%). Mean thickness of ligamentum flavum was significantly higher at all levels in patients with amyloid (p < .05). Patients with amyloid deposits were older (73.1 ± 9.2 vs. 64.6 ± 10.1 years, p = .01). No differences in sex, comorbidities, previous surgery for carpal tunnel syndrome or LSS were observed.

CONCLUSIONS

Amyloid, mostly of the ATTR subtype, was found in four out of five patients with LSS and is associated with age and ligamentum flavum thickness. Histopathological work-up of ligamentum flavum might inform future decision making.

Current clinical use of speckle-tracking strain imaging: insights from a worldwide survey from the European Association of Cardiovascular Imaging (EACVI)

AIMS

Speckle-tracking echocardiography (STE) strain imaging has been a major advancement in myocardial function quantification. We aimed to explore current worldwide clinical application of STE.

METHODS AND RESULTS

Access, feasibility, access, and clinical implementation of STE were investigated with a worldwide open-access online survey of the European Association of Cardiovascular Imaging. Participants (429 respondents and 77 countries) from tertiary centres (46%), private clinics, or public hospitals (54%) using different vendors for data acquisition and analysis were represented. Despite almost universal access (98%) to STE, only 39% of the participants performed and reported STE results frequently (>50%). Incomplete training and time constraints were the main reasons for not using STE more regularly. STE was mainly used to assess the LV (99%) and less frequently the right ventricular (57%) and the left atrial (46%) function. Cardiotoxicity (88%) and cardiac amyloidosis (87%) were the most frequent reasons for the clinical use of LV STE. Left atrial STE was used most frequently for the diagnosis of diastolic dysfunction and right ventricular STE for the assessment of right ventricle (RV) function in pulmonary hypertension (51%). Frequency of STE use, adherence to optimal techniques, and clinical appropriateness of STE differed according to training experience and across vendors. Key suggestions outlined by respondents to increase the clinical use of STE included improved reproducibility (48%) and standardization of strain values across vendors (42%).

CONCLUSION

Although STE is now readily available, it is underutilized in the majority of centres. Structured training, improved reproducibility, and inter-vendor standardization may increase its uptake.

Musculoskeletal manifestations associated with transthyretin-mediated (ATTR) amyloidosis: a systematic review

BACKGROUND

Hereditary and wild-type transthyretin-mediated (ATTRv and ATTRwt) amyloidoses result from the misfolding of transthyretin and aggregation of amyloid plaques in multiple organ systems. Diagnosis of ATTR amyloidosis is often delayed due to its heterogenous and non-specific presentation. This review investigates the association of musculoskeletal (MSK) manifestations with ATTR amyloidosis and the delay from the onset of these manifestations to the diagnosis of ATTR amyloidosis.

METHODS

This systematic review utilized Medline and EMBASE databases. Search criteria were outlined using a pre-specified patient, intervention, comparator, outcome, time, study (PICOTS) criteria and included: amyloidosis, ATTR, and MSK manifestations. Publication quality was assessed utilizing Joanna Briggs Institute (JBI) critical appraisal checklists. The search initially identified 7,139 publications, 164 of which were included. PICOTS criteria led to the inclusion of epidemiology, clinical burden and practice, pathophysiology, and temporality of MSK manifestations associated with ATTR amyloidosis. 163 publications reported on ATTR amyloidosis and MSK manifestations, and 13 publications reported on the delay in ATTR amyloidosis diagnosis following the onset of MSK manifestations.

RESULTS

The MSK manifestation most frequently associated with ATTR amyloidosis was carpal tunnel syndrome (CTS); spinal stenosis (SS) and osteoarthritis (OA), among others, were also identified. The exact prevalence of different MSK manifestations in patients with ATTR amyloidosis remains unclear, as a broad range of prevalence estimates were reported. Moreover, the reported prevalence of MSK manifestations showed no clear trend or distinction in association between ATTRv and ATTRwt amyloidosis. MSK manifestations precede the diagnosis of ATTR amyloidosis by years, and there was substantial variation in the reported delay to ATTR amyloidosis diagnosis. Reports do suggest a longer diagnostic delay in patients with ATTRv amyloidosis, with 2 to 12 years delay in ATTRv versus 1.3 to 1.9 years delay in ATTRwt amyloidosis.

CONCLUSION

These findings suggest that orthopedic surgeons may play a role in the early diagnosis of and treatment referrals for ATTR amyloidosis. Detection of MSK manifestations may enable earlier diagnosis and administration of effective treatments before disease progression occurs.

Clinical characteristics and prognostic implications of orthopedic ligament disorders in patients with wild-type transthyretin amyloidosis cardiomyopathy

BACKGROUND

Wild-type transthyretin amyloidosis (ATTRwt) is associated with multiple ligament disorders (LD) such as carpal tunnel syndrome (CTS), lumbar spinal stenosis (LSS), and spontaneous tendon rupture (STR). No studies have investigated the prevalence of these LD in the same cohort of ATTRwt patients. Furthermore, the clinical characteristics and prognostic implications of such disorders have not been studied.

METHODS

From 2017 to 2022, 206 consecutive patients with ATTRwt were diagnosed and followed prospectively to the time of death or the censoring date of September 1st, 2022. Patients with and without LD were compared, and the presence of LD was used along with the baseline clinical, biochemical, and echocardiographic characteristics to predict hospitalization with worsening heart failure and death.

RESULTS

CTS surgery was performed in 34 % of the patients, 8 % were treated for LSS, and 10 % had experienced an STR. The median follow-up time was 706 days (312-1067). Hospitalization with worsening heart failure occurred more frequently in patients with LD compared to patients without LD (p = 0.035). Presence of LD or surgery for CTS were found to be independent predictors of worsening heart failure with a hazard ratio of 2.0 (p = 0.01). The mortality was comparable between patients with and without LD (p = 0.10).

CONCLUSION

Orthopedic disorders are prevalent in ATTRwt cardiomyopathy, and presence of LD was an independent predictor of hospitalization with worsening heart failure.

Prevalence of Cardiac Amyloidosis in Patients Undergoing Carpal Tunnel Release With Amyloid Deposition

BACKGROUND

Carpal tunnel syndrome (CTS) is considered an early sign of cardiac amyloidosis (CA) because amyloid deposition is often confirmed in the tenosynovium removed during carpal tunnel release (CTR); however, the prevalence of concomitant CA is unclear.

METHODS AND RESULTS

We prospectively examined 700 patients who underwent CTR and evaluated amyloid deposition after tenosynovium removal. Amyloid deposition was observed in 261 (37%) patients, who were significantly older and predominantly male (P<0.05). Of them, 120 agreed to cardiac screening. We performed 99 mTc-labeled pyrophosphate (99 mTc-PYP) scintigraphy in 12 patients who met either of the following criteria: (1) interventricular septal diameter (IVSd) ≥14 mm or (2) 12 mm ≤ IVSd < 14 mm with above-normal limits in high-sensitivity cardiac troponin T (hs-cTnT). Six patients (50%) had positive findings on 99 mTc-PYP scintigraphy and were diagnosed with wild-type transthyretin CA. Concomitant CA was observed in 6/120 (5%) CTR patients with amyloid deposition and 50% (6/12) in patients with left ventricular hypertrophy (≥12 mm) with increased hs-cTnT levels.

CONCLUSIONS

Amyloid deposition was frequently observed in the removed tenosynovium of elderly men with CTS. Cardiac screening may be useful for early diagnosis of CA in patients undergoing CTR with amyloid deposition.

Transthyretin derived amyloid deposits in the atrium and the aortic valve: insights from multimodality evaluations and mid-term follow up

BACKGROUND

Recent studies have reported atrial involvement and coexistence of aortic stenosis in transthyretin (ATTR) cardiac amyloidosis (CA). However, pathological reports of extraventricular ATTR amyloid deposits in atrial structures or heart valves are limited, and the clinical implications of ATTR amyloid deposits outside the ventricles are not fully elucidated.

CASE PRESENTATION

We report 3 cases of extraventricular ATTR amyloid deposits confirmed in surgically resected aortic valves and left atrial structures, all of which were unlikely to have significant ATTR amyloidosis infiltrating the ventricles as determined by multimodality evaluation including ^99mtechnetium-pyrophosphate scintigraphy, cardiac magnetic resonance, endomyocardial biopsy and their mid-term clinical course up to 5 years. These findings suggested that these were extraventricular ATTR amyloid deposits localized in the aortic valve and the left atrium.

CONCLUSIONS

While long-term observation is required to fully clarify whether these extraventricular ATTR amyloid deposits are truly localized outside the ventricles or are early stages of ATTR-CA infiltrating the ventricles, our 3 cases with multimodality evaluations and mid-term follow up suggest the existence of extraventricular ATTR amyloid deposits localized in the aortic valve and left atrial structures.

Risk stratification in transthyretin-related cardiac amyloidosis

Transthyretin related cardiac amyloidosis (TTR-CA) is an infiltrative cardiomyopathy that cause heart failure with preserved ejection fraction, mainly in aging people. Due to the introduction of a non invasive diagnostic algorithm, this disease, previously considered to be rare, is increasingly recognized. The natural history of TTR-CA includes two different stages: a presymptomatic and a symptomatic stage. Due to the availability of new disease-modifying therapies, the need to reach a diagnosis in the first stage has become impelling. While in variant TTR-CA an early identification of the disease may be obtained with a genetic screening in proband's relatives, in the wild-type form it represents a challenging issue. Once the diagnosis has been made, in order to identifying patients with a higher risk of cardiovascular events and death it is necessary to focus on risk stratification. Two prognostic scores have been proposed both based on biomarkers and laboratory findings. However, a multiparametric approach combining information from electrocardiogram, echocardiogram, cardiopulmonary exercise test and cardiac magnetic resonance may be warranted for a more comprehensive risk prediction. In this review, we aim at evaluating a step by step risk stratification, providing a clinical diagnostic and prognostic approach for the management of patients with TTR-CA.

Screening approaches to cardiac amyloidosis in different clinical settings: Current practice and future perspectives

Cardiac amyloidosis is a serious and progressive infiltrative disease caused by the deposition of amyloid fibrils in the heart. In the last years, a significant increase in the diagnosis rate has been observed owing to a greater awareness of its broad clinical presentation. Cardiac amyloidosis is frequently associated to specific clinical and instrumental features, so called "red flags", and it appears to occur more commonly in particular clinical settings such as multidistrict orthopedic conditions, aortic valve stenosis, heart failure with preserved or mildly reduced ejection fraction, arrhythmias, plasma cell disorders. Multimodality approach and new developed techniques such PET fluorine tracers or artificial intelligence may contribute to strike up extensive screening programs for an early recognition of the disease.

Impact of Carpal Tunnel Syndrome Surgery on Early Diagnosis and Treatment of Transthyretin Cardiac Amyloidosis

Background and Objectives: Cardiac amyloidosis is an infiltrative, progressive, and restrictive cardiomyopathy that leads to heart failure, reduces life quality, and causes death. This is a multisystem disorder caused by mutations of the transthyretin protein and is associated not only with cardiac diseases or carpal tunnel syndrome but also with nerve, liver, lung, gastrointestinal tract, kidney, or eye pathologies. Carpal tunnel syndrome is an early red-flag symptom of transthyretin (TTR) cardiac amyloidosis; therefore, screening for unsuspected cardiac amyloidosis can be performed through histological testing of flexor retinaculum specimens gathered during carpal tunnel release surgery. Our case highlights that early detection and accurate diagnosis of a disease are important factors for improving clinical outcomes in patients with TTR amyloidosis. Case Summary: We report the case of a 71-year-old man who presented with bilateral carpal tunnel syndrome. Amyloid deposits were detected after carpal tunnel release surgery through histological testing of the synovial tissue. The patient was sent for a cardiological evaluation. Physical examination, laboratory tests, and the ECG revealed no significant changes. The diagnosis of amyloidosis was confirmed with multimodality imaging in the early stage, which helped to start specific medicamental treatment with the transthyretin stabilizer tafamidis. Conclusions: Our objective is to highlight the early recognition and specific medicamental treatment of cardiac amyloidosis for better patient prognosis and outcomes.

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.