Cardiac amyloidosis: updates in diagnosis and management

Cardiomegaly: Navigating the uncharted territories of heart failure - A multimodal radiological journey through advanced imaging, pathophysiological landscapes, and innovative therapeutic frontiers

Cardiomegaly is among the disorders categorized by a structural enlargement of the heart by any of the situations including pregnancy, resulting in damage to heart muscles and causing trouble in normal heart functioning. Cardiomegaly can be defined in terms of dilatation with an enlarged heart and decreased left or biventricular contraction. The genetic origin of cardiomegaly is becoming more evident due to extensive genomic research opening up new avenues to ensure the use of precision medicine. Cardiomegaly is usually assessed by using an array of radiological modalities, including computed tomography (CT) scans, chest X-rays, and MRIs. These imaging techniques have provided an important opportunity for the physiology and anatomy of the heart. This review aims to highlight the complexity of cardiomegaly, highlighting the contribution of both ecological and genetic variables to its progression. Moreover, we further highlight the worth of precise clinical diagnosis, which comprises blood biomarkers and electrocardiograms (EKG ECG), demonstrating the significance of distinguishing between numerous basic causes. Finally, the analysis highlights the extensive variation of treatment lines, such as lifestyle modifications, prescription drugs, surgery, and implantable devices, although highlighting the critical need for individualized and personalized care.

Myocardial Transit Time Mapping by CMR: A Novel Indicator of Microcirculatory Dysfunction in Cardiac Amyloidosis

Cardiac amyloidosis (CA) is characterized by the deposition of amyloid fibrils within the myocardium, resulting in a restrictive physiology. Although microvascular dysfunction is a common feature, it is difficult to assess. This study aimed to explore myocardial transit time (MyoTT) by cardiovascular magnetic resonance (CMR) as a potential novel parameter of microcirculatory dysfunction in CA. This prospective study enrolled 20 CA patients and 20 control subjects. CMR acquisition included cine imaging, pre- and post-contrast T1 mapping, and MyoTT assessment, which was calculated from the time delay in contrast agent arrival between the aortic root and coronary sinus (CS). Compared to the control group, patients with CA exhibited significantly reduced left ventricular (LV) ejection fraction and myocardial strain, an increase in LV global peak wall thickness (LVGPWT), extracellular volume fraction (ECV), and prolonged MyoTT (14.4 ± 3.8 s vs. 7.7 ± 1.5 s, p < 0.001). Moreover, patients at Mayo stage III had a significantly longer MyoTT compared to those at stage I/II. MyoTT showed a positive correlation with the ECV, LVGPWT, and LV global longitudinal strain (LV-GLS) (p < 0.05). The area under the curve (AUC) for MyoTT was 0.962, demonstrating diagnostic performance comparable to that of the ECV (AUC 0.995) and LV-GLS (AUC 0.950) in identifying CA. MyoTT is significantly prolonged in patients with CA, correlating with fibrosis markers, remodeling, and dysfunction. As a novel parameter of coronary microvascular dysfunction (CMD), MyoTT has the potential to be an integral biomarker in multiparametric CMR assessment of CA.

Impact of Baseline Neuropathy Severity on Vutrisiran Treatment Response in the Phase 3 HELIOS-A Study

INTRODUCTION

Hereditary transthyretin (ATTRv, v for variant) amyloidosis is a rare, progressive, fatal disease with multisystem manifestations, caused by pathogenic variants in the transthyretin (TTR) gene. Vutrisiran, an RNA interference therapeutic that results in rapid TTR knockdown, improved neuropathy and quality of life (QOL) versus external placebo in patients with ATTRv amyloidosis with polyneuropathy in the phase 3 HELIOS-A study (NCT03759379). This post hoc analysis evaluates the impact of baseline neuropathy severity on response to vutrisiran treatment.

METHODS

Patients were randomized (3:1) to vutrisiran (n = 122; 25 mg subcutaneous injection once every 3 months) or patisiran (n = 42; 0.3 mg/kg intravenous infusion once every 3 weeks), which served as a reference group. In this post hoc analysis, patients were grouped into quartiles of increasing baseline Neuropathy Impairment Score (NIS): Quartile (Q)1 ≥ 5.0 to ≤ 20.5; Q2 > 20.5 to ≤ 44.1; Q3 > 44.1 to ≤ 73.1; Q4 > 73.1 to ≤ 127.0. Mean change from baseline to Month 18 was summarized by quartile for a range of efficacy endpoints.

RESULTS

Across all baseline NIS quartiles, vutrisiran demonstrated benefit versus external placebo in measures of neuropathy severity (modified NIS + 7), QOL (Norfolk Quality of Life-Diabetic Neuropathy), disability (Rasch-built Overall Disability Scale), gait speed (10-m walk test), and nutritional status (modified body mass index). Overall, patients in lower versus higher NIS quartiles (less severe neuropathy) at baseline maintained better scores at Month 18. The external placebo group progressively worsened in all measures at Month 18.

CONCLUSIONS

Vutrisiran demonstrated benefit in neurologic function and other key efficacy measures versus external placebo across all four baseline neuropathy severity quartiles. Patients initiating vutrisiran earlier in their disease course retained the highest neurologic function level after 18 months, highlighting the importance of early diagnosis and treatment.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT03759379.

Diagnosis and treatment of hereditary transthyretin amyloidosis with polyneuropathy in the United States: Recommendations from a panel of experts

Hereditary transthyretin (ATTRv; v for variant) amyloidosis is a rare, multisystem, progressive, and fatal disease in which polyneuropathy is a cardinal manifestation. Due to a lack of United States (US)-specific guidance on ATTRv amyloidosis with polyneuropathy, a panel of US-based expert clinicians convened to address identification, monitoring, and treatment of this disease. ATTRv amyloidosis with polyneuropathy should be suspected in unexplained progressive neuropathy, especially if associated with systemic symptoms or family history. The diagnosis is confirmed through genetic testing, biopsy, or cardiac technetium-based scintigraphy. Treatment should be initiated as soon as possible after diagnosis, with gene-silencing therapeutics recommended as a first-line option. Consensus is lacking on what represents "disease progression" during treatment; however, the aggressive natural history of this disease should be considered when evaluating the effectiveness of any therapy.

Effect of Tafamidis on Cardiac Function in Patients With Transthyretin Amyloid Cardiomyopathy: A Post Hoc Analysis of the ATTR-ACT Randomized Clinical Trial

Importance

Tafamidis has been shown to improve survival in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) compared with placebo. However, its effect on cardiac function has not been fully characterized.

Objective

To examine the effect of tafamidis on cardiac function in patients with ATTR-CM.

Design, Setting, and Participants

This was an exploratory, post hoc analysis of the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT), a multicenter, international, double-blind, placebo-controlled phase 3 randomized clinical trial conducted from December 2013 to February 2018. The ATTR-ACT included 48 sites in 13 counties and enrolled patients aged 18 to 90 years with ATTR-CM. Data were analyzed from July 2018 to September 2023.

Intervention

Patients were randomized to tafamidis meglumine, 80 mg or 20 mg, or placebo for 30 months.

Main Outcomes and Measures

Patients were categorized based on left ventricular (LV) ejection fraction at enrollment as having heart failure with preserved ejection fraction (≥50%), mildly reduced ejection fraction (41% to 49%), or reduced ejection fraction (≤40%). Changes from baseline to month 30 in LV ejection fraction, LV stroke volume, LV global longitudinal strain, and the ratio of early mitral inflow velocity to septal and lateral early diastolic mitral annular velocity (E/e') were compared in patients receiving tafamidis, 80 mg, vs placebo.

Results

A total of 441 patients were randomized in ATTR-ACT, and 436 patients had available echocardiographic data. Of 436 included patients, 393 (90.1%) were male, and the mean (SD) age was 74 (7) years. A total of 220 (50.5%), 119 (27.3%), and 97 (22.2%) had heart failure with preserved, mildly reduced, and reduced LV ejection fraction, respectively. Over 30 months, there was less pronounced worsening in 4 of the echocardiographic measures in patients receiving tafamidis, 80 mg (n = 176), vs placebo (n = 177) (least squares mean difference: LV stroke volume, 7.02 mL; 95% CI, 2.55-11.49; P = .002; LV global longitudinal strain, -1.02%; 95% CI, -1.73 to -0.31; P = .005; septal E/e', -3.11; 95% CI, -5.50 to -0.72; P = .01; lateral E/e', -2.35; 95% CI, -4.01 to -0.69; P = .006).

Conclusions and Relevance

Compared with placebo, tafamidis, 80 mg, attenuated the decline of LV systolic and diastolic function over 30 months in patients with ATTR-CM. Approximately half of patients had mildly reduced or reduced LV ejection fraction at enrollment, suggesting that ATTR-CM should be considered as a possible diagnosis in patients with heart failure regardless of underlying LV ejection fraction.

Trial Registration

ClinicalTrials.gov Identifier: NCT01994889.

Electrocardiographic heterogeneity of patients with variant transthyretin amyloid cardiomyopathy: Genotype-phenotype correlations

BACKGORUND

Hereditary transthyretin(vATTR) cardiac amyloidosis has extremely different features according to the type of transthyretin(TTR) mutation. Data about electrocardiographic findings(ECG) in vATTR are limited and not informative of genotype correlation. Aim of this study is to analyze ECG characteristics and their correlation to clinical and echocardiographic aspects in patients with vATTR, focusing on different TTR mutations.

METHODS AND RESULTS

This is a multicentric, retrospective, observational study performed in six Italian referral centres. We divided patients in two groups, according to the previously described phenotypic manifestations of the TTR mutation. Of 64 patients with vATTR, 23(36%) had prevalent cardiac(PC) TTR mutations and 41(64%) patients had a prevalent neurological(PN) TTR mutations. Patients with PC mutations were more frequently males and older, with advanced NAC staging. At baseline ECG, atrial fibrillation was more common in patients with PC, while pacemaker induced rhythm in PN mutations. PQ and QRS durations were longer and voltage to mass ratio was lower in PC mutations. Different TTR mutations tend to have distinctive ECG features.

CONCLUSIONS

ECG in vATTR is extremely heterogeneous and the specific mutations are associated with distinct instrumental and clinical features. The differences between PN and PC vATTR are only partially explained by the different degree of cardiac infiltration.

Natriuretic Peptides and Cardiac Troponins: Markers of Disease Progression and Risk in Light Chain Cardiac Amyloidosis

PURPOSE OF REVIEW

Light chain (AL) amyloidosis can cause an infiltrative cardiomyopathy that can result in symptomatic heart failure. The vague, nonspecific onset of signs and symptoms may lead to a delay in diagnosis and treatment leading to poor outcomes. Cardiac biomarkers, such as troponins and natriuretic peptides, play a pivotal role in diagnosis, determining prognosis, and assessing treatment response in patients with AL amyloidosis. Because of the evolving landscape for both diagnosis and treatment of AL cardiac amyloidosis, we review the critical role these and other biomarkers play in the clinical management of this disease.

RECENT FINDINGS

A number of conventional cardiac and noncardiac serum biomarkers are commonly used in AL cardiac amyloidosis and may be surrogates for cardiac involvement and inform prognosis. These include typical heart failure biomarkers such as levels of circulating natriuretic peptides as well as cardiac troponins. Other noncardiac biomarkers frequently measured in AL cardiac amyloidosis included difference between the involved and uninvolved free light chains (dFLC) and markers of endothelial cell activation and damage such as von Willebrand factor antigen and matrix metalloproteinases. AL amyloidosis can lead to cardiac involvement which has been associated with poor outcomes, especially if not identified and treated early. Natriuretic peptides and cardiac troponins are cornerstones for the diagnosis and management of AL cardiac amyloidosis. Their levels may represent cardiac stress, injury, and possibly degree of cardiac involvement, and they play a key role in AL amyloidosis disease staging.

Impact of Vutrisiran on Quality of Life and Physical Function in Patients with Hereditary Transthyretin-Mediated Amyloidosis with Polyneuropathy

INTRODUCTION

Hereditary transthyretin (ATTRv; v for variant) amyloidosis, also known as hATTR amyloidosis, is a progressive and fatal disease associated with rapid deterioration of physical function and patients' quality of life (QOL). Vutrisiran, a subcutaneously administered RNA interference (RNAi) therapeutic that reduces hepatic production of transthyretin, was assessed in patients with ATTRv amyloidosis with polyneuropathy in the pivotal HELIOS-A study.

METHODS

The phase 3 open-label HELIOS-A study investigated the efficacy and safety of vutrisiran in patients with ATTRv amyloidosis with polyneuropathy, compared with an external placebo group from the APOLLO study of the RNAi therapeutic patisiran. Measures of QOL and physical function were assessed.

RESULTS

At month 18, vutrisiran improved Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) total score (least squares mean difference [LSMD] in change from baseline [CFB]: -21.0; p = 1.84 × 10-10) and Norfolk QOL-DN domain scores, compared with external placebo. This benefit relative to external placebo was evident across all baseline polyneuropathy disability (PND) scores and most pronounced in patients with baseline PND scores I-II. Compared with external placebo, vutrisiran also demonstrated benefit in EuroQoL-Visual Analog Scale (EQ-VAS) score (LSMD in CFB: 13.7; nominal p = 2.21 × 10-7), 10-m walk test (LSMD in CFB: 0.239 m/s; p = 1.21 × 10-7), Rasch-built Overall Disability Score (LSMD in CFB: 8.4; p = 3.54 × 10-15), and modified body mass index (mBMI) (LSMD in CFB: 140.7; p = 4.16 × 10-15) at month 18. Overall, Norfolk QOL-DN, EQ-VAS, and mBMI improved from pretreatment baseline with vutrisiran, whereas all measures worsened from baseline in the external placebo group. At month 18, Karnofsky Performance Status was stable/improved from baseline in 58.2/13.1% with vutrisiran versus 34.7/8.1% with external placebo.

CONCLUSION

Vutrisiran treatment provided significant clinical benefits in multiple measures of QOL and physical function in patients with ATTRv amyloidosis with polyneuropathy. Benefits were most pronounced in patients with earlier-stage disease, highlighting the importance of early diagnosis and treatment.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT03759379.

The patient pathway in ATTR-CM in Greece and how to improve it: A multidisciplinary perspective

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underdiagnosed disease associated with high mortality rates and the patient journey is characterized by increased complexities. Accurate and timely diagnosis and prompt initiation of disease-modifying treatment constitute the contemporary unmet need in ATTR-CM. ATTR-CM diagnosis is characterized by considerable delays and high rates of misdiagnosis. The majority of patients present themselves to primary care physicians, internists, and cardiologists, and many have undergone repeated medical evaluations before an accurate diagnosis has been made. The disease is diagnosed mainly after the development of heart failure symptoms, reflecting a long course of missed opportunities before diagnosis and disease-modifying treatment initiation. Early referral to experienced centers ensures prompt diagnosis and therapy. Early diagnosis, better care coordination, acceleration of digital transformation and reference networks, encouragement of patient engagement, and implementation of rare disease registries are the key pillars to improve the ATTR-CM patient pathway and achieve important benefits in ATTR-CM outcomes.

Usefulness of automatic assessment for longitudinal strain to diagnose wild-type transthyretin amyloid cardiomyopathy

Background

Left ventricular (LV) apical sparing by transthoracic echocardiography (TTE) has not been widely accepted to diagnose transthyretin amyloid cardiomyopathy (ATTR-CM), because it is time consuming and requires a level of expertise. We hypothesized that automatic assessment may be the solution for these problems.

Methods-and-Results

We enrolled 63 patients aged ≥70 years who underwent ^99mTc-labeled pyrophosphate (^99mTc-PYP) scintigraphy on suspicion of ATTR-CM and performed TTE by EPIQ7G, and had enough information for two-dimensional speckle tracking echocardiography at Kumamoto University Hospital from January 2016 to December 2019. LV apical sparing was described as a high relative apical longitudinal strain (LS) index (RapLSI). Measurement of LS was repeated using the same apical images with three different measurement packages as follows: (1) full-automatic assessment, (2) semi-automatic assessment, and (3) manual assessment. The calculation time for full-automatic assessment (14.7 ± 1.4 sec/patient) and semi-automatic assessment (66.7 ± 14.4 sec/patient) were significantly shorter than that for manual assessment (171.2 ± 59.7 sec/patient) (p < 0.01 for both). Receiver operating characteristic curve analysis showed that the area under curve of the RapLSI evaluated by full-automatic assessment for predicting ATTR-CM was 0.70 (best cut-off point; 1.14 [sensitivity 63%, specificity 81%]), by semi-automatic assessment was 0.85 (best cut-off point; 1.00 [sensitivity, 66%; specificity, 100%]) and by manual assessment was 0.83 (best cut-off point; 0.97 [sensitivity, 72%; specificity, 97%]).

Conclusion

There was no significant difference between the diagnostic accuracy of RapLSI estimated by semi-automatic assessment and that estimated by manual assessment. Semi-automatically assessed RapLSI is useful to diagnose ATTR-CM in terms of rapidity and diagnostic accuracy.

Status and Future Directions of Therapeutics and Prognosis of Cardiac Amyloidosis

Accumulation of aberrant proteins in the heart causes cardiac amyloidosis, an uncommon and complicated illness. It can be classified into two main types: light chain (AL) and transthyretin (ATTR). The diagnosis of cardiac amyloidosis is challenging due to its non-specific clinical presentation and lack of definitive diagnostic tests. Diagnostic accuracy has increased with the advent of modern imaging methods, including cardiac magnetic resonance imaging (MRI) and positron emission tomography (PET) scans. Depending on the severity of cardiac amyloidosis, a number of treatments may be attempted and specified according to the subtype of amyloidosis and the presence of complications. However, there are still significant challenges in treating this condition due to its complexity and lack of effective treatments. The prognosis for patients with cardiac amyloidosis is poor. Despite recent advances in diagnosis and treatment, there is still a need for more effective treatments to improve outcomes for patients with this condition. Therefore, we aim to review the current and future therapeutics reported in the literature and among ongoing clinical trials recruiting patients with CA.

Prognostic value of right ventricular global longitudinal strain in patients with immunoglobulin light-chain cardiac amyloidosis

Aims

Left ventricular (LV) global longitudinal strain (GLS) (LV-GLS) is a strong and independent predictor of outcomes in patients with immunoglobulin light-chain (AL) cardiac amyloidosis. This study was performed to investigate whether right ventricular (RV) GLS (RV-GLS) provides prognostic information in patients with AL amyloidosis.

Methods and results

Among 74 patients who were diagnosed with AL cardiac amyloidosis at Kumamoto University Hospital from December 2005 to December 2022, 65 patients who had enough information for two-dimensional speckle tracking imaging and did not receive chemotherapy before the diagnosis of cardiac amyloidosis were retrospectively analysed. During a median follow-up of 359 days, 29 deaths occurred. In two-dimensional echocardiographic findings, LV-GLS, left atrium reservoir strain (LASr), and RV-GLS were significantly lower in the all-cause death group than in the survival group (LV-GLS: 8.9 ± 4.2 vs. 11.7 ± 3.9, P < 0.01; LASr: 9.06 ± 7.28 vs. 14.09 ± 8.32, P < 0.05; RV-GLS: 12.0 ± 5.1 vs. 16.8 ± 4.0, P < 0.01). Multivariable Cox proportional hazard analysis showed RV-GLS was significantly and independently associated with all-cause death in patients with AL cardiac amyloidosis (hazard ratio 0.85; 95% confidence interval, 0.77-0.94; P < 0.01). Receiver operating characteristic analysis showed that the area under the curve of RV-GLS for all-cause death was 0.774 and that the best cut-off value of RV-GLS was 14.5% (sensitivity, 75%; specificity, 72%). In the Kaplan-Meier analysis, patients with AL cardiac amyloidosis who had low RV-GLS (<14.5%) had a significantly higher probability of all-cause death (P < 0.01).

Conclusion

RV-GLS has prognostic value in patients with AL cardiac amyloidosis and provides greater prognostic power than LV-GLS and LASr.

Amylo-AFFECT-QOL, a self-reported questionnaire to assess health-related quality of life and to determine the prognosis in cardiac amyloidosis

Background and aims

Self-reported questionnaires are useful for estimating the health-related quality of life (HR-QoL), impact of interventions, and prognosis. To our knowledge, no HR-QoL questionnaire has been developed for cardiac amyloidosis (CA). This study aimed to validate Amylo-AFFECT-QOL questionnaire to assess HR-QoL and its prognostic value in CA.

Methods

A self-reported questionnaire, “Amylo-AFFECT” had been designed and validated for CA symptoms evaluation and screening by physicians. It was adapted here to assess HR-QoL (Amylo-AFFECT-QOL) and its prognostic value in CA. To validate the theoretical model, internal consistency and convergent validity were assessed, particularly correlations between Amylo-AFFECT-QOL and the HR-QoL Minnesota Living Heart Failure (MLHF) questionnaire.

Results

Amylo-AFFECT-QOL was completed by 515 patients, 425 of whom (82.5%) had CA. Wild-type and hereditary transthyretin amyloidosis (ATTRwt and ATTRv) and immunoglobulin light-chain amyloidosis (AL) were diagnosed in 47.8, 14.7, and 18.8% of cases, respectively. The best HR-QoL evaluation was obtained with five dimensions: “Heart failure,” “Vascular dysautonomia,” “Neuropathy,” “Ear, gastrointestinal, and urinary dysautonomia,” and “Skin or mucosal involvement.” The global Amylo-AFFECT-QOL and MLHF scores showed significant positive correlations (rs = 0.72, p &lt; 0.05). Patients with a final diagnosis of CA had a global Amylo-AFFECT-QOL score significantly higher than the control group composed by patients with other diagnoses (22.2 ± 13.6 vs. 16.2 ± 13.8, respectively, p-value &lt; 0.01). According to the Amylo-AFFECT-QOL global results, ATTRv patients’ QoL was more affected than AL patients’ QoL or ATTRwt patients’ QoL. Patients with a higher HR-QoL score had a greater risk of death or heart transplant after 1 year of follow-up (log-rank &lt; 0.01).

Conclusion

Amylo-AFFECT-QOL demonstrates good psychometric properties and is useful for quantifying HR-QoL and estimating CA prognosis. Its use may help to improve overall management of patients with CA.

Detection and Diagnosis of Cardiac Amyloidosis in Egypt

Cardiac amyloidosis is a life-threatening disease that occurs when amyloid proteins, most commonly immunoglobulin light chain or transthyretin, mutate or become unstable, misfold, deposit as amyloid fibrils, and accumulate in the myocardium. Early diagnosis of cardiac amyloidosis is hindered by insufficient awareness, specifically regarding clinical red flags and diagnostic pathways. Cardiac amyloidosis diagnosis comprises two important phases, clinical suspicion (phase one) followed by definitive diagnosis (phase two). Each phase is associated with specific clinical techniques. For example, clinical features, electrocardiography, echocardiography, and cardiac magnetic resonance imaging serve to raise suspicion of cardiac amyloidosis and facilitate early diagnosis, whereas laboratory tests (i.e., blood or urine electrophoresis with immunofixation), biopsy, scintigraphy-based nuclear imaging, and genetic testing provide a definitive diagnosis of cardiac amyloidosis. In Egypt, both the lack of cardiac amyloidosis awareness amongst healthcare providers and the unavailability of clinical expertise for the use of diagnostic techniques must be overcome to improve the prognosis of cardiac amyloidosis in the region. Previously published diagnostic algorithms for cardiac amyloidosis have amalgamated techniques that can raise clinical suspicions of cardiac amyloidosis with those that definitively diagnose cardiac amyloidosis. Though such algorithms have been successful in developed countries, diagnostic tools like echocardiography, scintigraphy, and cardiac magnetic resonance imaging are not ubiquitously available across Egyptian facilities. This review presents the current state of knowledge regarding cardiac amyloidosis in Egypt and outlines a new diagnostic algorithm which leverages regional nuclear imaging expertise. Importantly, the proposed diagnostic algorithm guides accurate amyloid-typing to mitigate misdiagnosis and erroneous treatment selection and improve the cardiac amyloidosis diagnostic accuracy in Egypt.

Impact of baseline polyneuropathy severity on patisiran treatment outcomes in the APOLLO trial

OBJECTIVE

Assess how baseline polyneuropathy severity impacts response to patisiran regarding neurologic impairment and quality of life (QOL) in patients with hereditary transthyretin-mediated amyloidosis (ATTRv amyloidosis).

METHODS

This post hoc analysis grouped patients from the Phase 3 APOLLO study (n = 225) by baseline Neuropathy Impairment Score (NIS) into quartiles: 6-<31; 31-<57; 57-<85.5; 85.5-141.6. Neurologic impairment (modified NIS+7 [mNIS+7], NIS total score), disability (Rasch-built Overall Disability Scale [R-ODS]), gait speed (10-meter walk test [10-MWT]), grip strength, and QOL (Norfolk Quality of Life-Diabetic Neuropathy [Norfolk QOL-DN] questionnaire) were assessed.

RESULTS

Across all baseline NIS quartiles, patisiran improved several clinical markers of disease compared with placebo at 18 months. Patients in lower NIS quartiles, treated with patisiran earlier in the disease course, maintained better scores in mNIS+7, NIS total score, R-ODS, 10-MWT, grip strength, and Norfolk QOL-DN versus those in higher NIS quartiles, while placebo-treated patients experienced worsening of all functional measures after 18 months across all quartiles.

CONCLUSIONS

Patisiran treatment improved neurologic function and QOL across a wide range of baseline polyneuropathy severities versus placebo. Timing of treatment initiation in patients with ATTRv amyloidosis remains critical for the preservation of function.(ClinicalTrials.gov number, NCT01960348).

Efficacy and safety of vutrisiran for patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy: a randomized clinical trial

BACKGROUND

The study objective was to assess the effect of vutrisiran, an RNA interference therapeutic that reduces transthyretin (TTR) production, in patients with hereditary transthyretin (ATTRv) amyloidosis with polyneuropathy.

METHODS

HELIOS-A was a phase 3, global, open-label study comparing the efficacy and safety of vutrisiran with an external placebo group (APOLLO study). Patients were randomized 3:1 to subcutaneous vutrisiran 25 mg every 3 months (Q3M) or intravenous patisiran 0.3 mg/kg every 3 weeks (Q3W) for 18 months.

RESULTS

HELIOS-A enrolled 164 patients (vutrisiran, n = 122; patisiran reference group, n = 42); external placebo, n = 77. Vutrisiran met the primary endpoint of change from baseline in modified Neuropathy Impairment Score +7 (mNIS+7) at 9 months (p = 3.54 × 10^-12), and all secondary efficacy endpoints; significant improvements versus external placebo were observed in Norfolk Quality of Life-Diabetic Neuropathy, 10-meter walk test (both at 9 and 18 months), mNIS+7, modified body-mass index, and Rasch-built Overall Disability Scale (all at 18 months). TTR reduction with vutrisiran Q3M was non-inferior to within-study patisiran Q3W. Most adverse events were mild or moderate in severity, and consistent with ATTRv amyloidosis natural history. There were no drug-related discontinuations or deaths.

CONCLUSIONS

Vutrisiran significantly improved multiple disease-relevant outcomes for ATTRv amyloidosis versus external placebo, with an acceptable safety profile.

CLINICALTRIALS.GOV

NCT03759379.

Inotersen to Treat Polyneuropathy Associated with Hereditary Transthyretin (hATTR) Amyloidosis

Background

Amyloidosis is a group of diseases with the common pathophysiology of protein misfolding and aberrant deposition in tissue. There are both acquired and hereditary forms of this disease, and this review focuses on the latter hereditary transthyretin-mediated (hATTR). hATTR affects about 50,000 individuals globally and mostly appears as one of three syndromes - cardiac, polyneuropathy, and oculoleptomeningeal. Polyneuropathy is the most common form, and there is usually some overlap in individual patients.

Results

Recently, novel therapeutic options emerged in the form of groundbreaking drugs, Patisiran and Inotersen, small interfering RNA molecules that target TTR and reduce the production of this protein. By targeting TTR mRNA transcripts, Inotersen decreases protein translation and production, reducing the deposition of misfolded proteins. It was shown to be both effective and safe for use and specifically formulated to concentrate in the liver - where protein production takes place.

Conclusion

hATTR is a rare, progressive, and debilitating disease. Its most common presentation is that of polyneuropathy, and it carries a very poor prognosis and a natural history conveying a median survival of < 12 years. Novel therapeutic options are groundbreaking by providing disease-modifying specific, targeted therapies against TTR production and deposition. The use of RNA interference (RNAi) opens the door to the treatment of hereditary diseases by targeting them at the genetic level.

Real-Life Evaluation of an Algorithm for the Diagnosis of Cardiac Amyloidosis

OBJECTIVE

To evaluate the real-life use of a modified Gillmore algorithm with a "one-stop-shop" approach, bone scintigraphy (BS), a monoclonal gammopathy test (GT), a salivary gland biopsy (SGB), and genetic testing performed at the same time for the diagnosis of cardiac amyloidosis at the French National Reference Centre for Cardiac Amyloidosis (Henri Mondor Hospital, Créteil, France).

METHODS

This retrospective cohort study included a total of 1222 patients with suspected amyloidosis who underwent BS and GT between June 2008 and May 2019.

RESULTS

Of 1222 patients, 349 had no cardiac uptake on BS and negative GT (BS-/GT-), 276 were BS-/GT positive (GT+), 420 patients were BS+/GT-, and 177 were BS+/GT+. Our one-stop-shop check-up enabled us to diagnose 892 (72.9%) patients; 330 (27.0%) patients required additional examinations, such as mass spectrometry and/or a cardiac biopsy. This subset notably included 112 patients with amyloid light chain amyloidosis. More than 64% of the patients with transthyretin amyloidosis or another type of amyloidosis were diagnosed during the one-stop shop visit. Sensitivity and specificity of BS for transthyretin amyloidosis diagnosis was 99% and 96%, respectively. For amyloid light chain diagnosis, sensitivity and specificity were 100% and 76%, respectively, for GT and 54% and 100%, respectively, for SGB. Of 910 transthyretin genetic tests, 205 (17%) detected mutations.

CONCLUSION

The results of our real-life cohort study confirmed the ability of a one-stop-shop approach with a modified Gillmore algorithm to diagnose cardiac amyloidosis and the interest of simultaneous testing for earlier diagnosis. The SGB has diagnostic value because it is easy, quick, and less invasive than a cardiac biopsy.

Wild type cardiac amyloidosis: is it time to order a nuclear technetium pyrophosphate SPECT imaging study?

Transthyretin (ATTR) amyloidosis is a debilitating systemic disease often associated with symptomatic cardiac involvement. Diagnosis has dramatically changed with the advent of Technetium-99 m pyrophosphate (Tc-PYP) single-photon emission computed tomography (SPECT). With the ability to diagnose ATTR amyloidosis noninvasively and offer newer therapies, it is increasingly important to identify which patients should be referred for this testing. Relative apical sparing of longitudinal strain on echocardiogram can be potentially used to screen such patients. We sought to describe electrocardiogram (ECG) and echocardiogram (TTE) findings, including relative apical sparing of longitudinal strain, in ATTR amyloidosis patients diagnosed non-invasively with ^99mTc-PYP imaging. This was a single-center, retrospective study with 64 patients who underwent ^99mTc-PYP imaging between June 2016 and February 2019. Relative apical longitudinal strain was calculated from left ventricular longitudinal strain (LV LS) values. No ECG parameters were meaningfully associated with of ^99 m Tc-PYP positive patients. LV mass index (p = 0.001), IVSd (p < 0.001), and LVPWd (< 0.001) demonstrated a highly significant difference between positive and negative ^99mTc-PYP groups. ^99mTc-PYP positive patients had a higher relative apical sparing of LV LS (p < 0.001), and notably, no ^99mTc-PYP negative patient had a ratio > 1.0. The finding of relative apical sparing of longitudinal strain can reliably guide clinicians in triaging which patients to consider ordering ^99mTc-PYP imaging for the noninvasive diagnosis of wild type cardiac amyloidosis. A patient with clinically suggestive features and an LV LS relative apical sparing ratio > 0.8 can be considered for ^99mTc-PYP imaging to evaluate for ATTR cardiac amyloidosis.

Heart Transplantation, Either Alone or Combined With Liver and Kidney, a Viable Treatment Option for Selected Patients With Severe Cardiac Amyloidosis

Heart transplantation in cardiac amyloidosis (CA) patients is possible and generally considered for transplantation if other organs are not affected. In this study, we aimed to describe and assess outcome in patients following heart transplantations at our CA referral center.

Methods

We assessed all CA patients that had heart transplantations at our center between 2005 and 2018. Patients with New York Heart Association status 3 out of 4, with poor short-term prognosis due to heart failure, despite treatment, and without multiple myeloma, systemic disease, severe neuropathic/digestive comorbidities, cancer, or worsening infections were eligible for transplantation. Hearts were transplanted by bicaval technique. Standard induction and immunosuppressive therapies were used. Survival outcome of CA patients after transplantation was compared with recipients with nonamyloid pathologies in France.

Results

Between 2005 and 2018, 23 CA patients had heart transplants: 17 (74%) had light chain (light chain amyloidosis [AL]) and 6 (26%) had hereditary transthyretin (hereditary transthyretin amyloidosis [ATTRv]) CA. Also, 13 (57%) were male, and the mean age at diagnosis was 56.5 y (range, 47.7-62.8). Among AL patients, 13 had heart-only and 5 had heart-kidney transplantations. Among ATTRv patients, 1 had heart-only and 5 had heart-liver transplantations. The 1-y survival rate after transplantation was 78%, 70% with AL, and 100% with ATTRv. At 2 y, 74% were alive: 65% with AL and 100% with ATTRv.

Conclusion

After heart transplantation, French CA and nonamyloid patients have similar survival outcomes. Among CA patients, ATTRv patients have better prognosis than those with AL, possibly due to the combined heart-liver transplantation. Selected CA patients should be considered for heart transplantations.

Patisiran treatment in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy after liver transplantation

Hereditary transthyretin-mediated (hATTR) amyloidosis, or ATTRv amyloidosis, is a progressive disease, for which liver transplantation (LT) has been a long-standing treatment. However, disease progression continues post-LT. This Phase 3b, open-label trial evaluated efficacy and safety of patisiran in patients with ATTRv amyloidosis with polyneuropathy progression post-LT. Primary endpoint was median transthyretin (TTR) reduction from baseline. Twenty-three patients received patisiran for 12 months alongside immunosuppression regimens. Patisiran elicited a rapid, sustained TTR reduction (median reduction [Months 6 and 12 average], 91.0%; 95% CI: 86.1%-92.3%); improved neuropathy, quality of life, and autonomic symptoms from baseline to Month 12 (mean change [SEM], Neuropathy Impairment Score, -3.7 [2.7]; Norfolk Quality of Life-Diabetic Neuropathy questionnaire, -6.5 [4.9]; least-squares mean [SEM], Composite Autonomic Symptom Score-31, -5.0 [2.6]); and stabilized disability (Rasch-built Overall Disability Scale) and nutritional status (modified body mass index). Adverse events were mild or moderate; five patients experienced ≥1 serious adverse event. Most patients had normal liver function tests. One patient experienced transplant rejection consistent with inadequate immunosuppression, remained on patisiran, and completed the study. In conclusion, patisiran reduced serum TTR, was well tolerated, and improved or stabilized key disease impairment measures in patients with ATTRv amyloidosis with polyneuropathy progression post-LT (www.clinicaltrials.gov NCT03862807).

The tricuspid annulus in amyloidosis with cardiac involvement: Detailed analysis from the three-dimensional speckle tracking echocardiographic MAGYAR-Path Study

Introduction

Amyloidosis is a rare condition due to extracellular deposition of excessive amount of protein in parenchymal tissues including the heart. The present study aimed to test whether cardiac amyloidosis (CA) is associated with morphological and functional abnormalities of the tricuspid annulus (TA). For this aim, the results of patients having CA were compared to age- and gender-matched healthy controls by three-dimensional speckle-tracking echocardiography (3DSTE). Moreover, differences in TA parameters between light-chain CA (AL-CA) and transthyretin CA (TTR-CA) were studies as well.

Materials and Methods

The study comprised 27 CA patients (mean age: 62.7 ± 9.1 years, 21 males), their results were compared to those of 20 age- and gender-matched healthy volunteers (59.3 ± 3.8 years, 13 males). Complete two-dimensional Doppler echocardiography and 3DSTE were performed in all CA patients and controls.

Results

Dilated end-diastolic and end-systolic TA diameter, area and perimeter could be detected in all CA patients and in the AL-CA and TTR-CA subgroups, as well. Although only a few TTR-CA patients were involved, morphologic TA parameters proved to be tendentiously higher as compared to those of AL-CA patients. Functional parameters of TA were found to be reduced in CA patients, which were more deteriorated in AL-CA patients.

Conclusions

Dilated TA is associated with its functional deterioration in CA.

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.

Utility and pitfalls of the electrocardiogram in the evaluation of cardiac amyloidosis

BACKGROUND

Cardiac amyloidosis is a protein misfolding disorder involving deposition of amyloid fibril proteins in the heart. The associated fibrosis of the conduction tissue results in conduction abnormalities and arrhythmias. "Classical" electrocardiogram (ECG) findings in cardiac amyloidosis include that of low voltage complexes with increased left ventricular wall thickness on echocardiography. However, this "classical" finding is neither sensitive nor specific. As cardiac amyloidosis is associated with a generally poor prognosis, the need for early recognition of this disease is important given the availability of new treatment options. In this review, we highlight 3 cases of patients with cardiac amyloidosis. Although presenting with typical clinical signs and symptoms, ECG for all 3 patients was not consistent with the classical findings described. They underwent further diagnostic tests which clinched the diagnosis of cardiac amyloidosis, allowing patients to receive targeted treatment. Through the review of the literature, we will highlight the different ECG patterns in patients with different types of cardiac amyloidosis and clinical scenarios, as well as the pitfalls of using ECG to identify the condition. Lastly, we also emphasize the current paradigms in diagnosing cardiac amyloidosis through the non-invasive methods of echocardiography, cardiac magnetic resonance imaging, and nuclear technetium-pyrophosphate imaging.

CONCLUSIONS

Electrocardiogram is often the first investigation used in evaluating many cardiac disorders, including cardiac amyloidosis. However, classical features of cardiac amyloidosis on ECG are often not present. A keen understanding on the ECG features of cardiac amyloidosis and knowledge of the diagnostic workflow is important to diagnose this condition.

Diagnostic Role of NT-proBNP in Patients with Cardiac Amyloidosis Involvement: A Meta-Analysis

Fundamento

A amiloidose é definida como um distúrbio caracterizado pela deposição de material proteico amiloide extracelular nos tecidos.

Objetivos

O N-terminal pró-peptídeo natriurético tipo-B (NT-proBNP) é usado para prever a amiloidose cardíaca (AC), mas seu efeito diagnóstico no comprometimento por AC ainda não é claro, especialmente em termos de especificidade e sensibilidade.

Métodos

Foi feita uma busca de literatura nos bancos de dados Pubmed, Embase e a biblioteca Cochrane, e o QUADAS 2 foi utilizado para avaliação da qualidade. O comando Midas no Stata 12.0 foi usado para analisar os indicadores dos sujeitos. O teste Q de Cochran e o I² foram usados como testes de heterogeneidade, e a heterogeneidade significativa foi definida como p <0,05 e/ou I² >50%. A análise de correlação de Spearman foi usada para avaliar o efeito de limiar, e o viés da publicação foi avaliado pelo teste de assimetria. A significância estatística foi definida em p <0,05.

Resultados

Como resultados, 10 conjuntos de dados de 7 estudos foram incluídos para análise, apresentando alta qualidade metodológica e pequenos vieses de confusão. A sensibilidade e a especificidade do NT-proBNP no diagnóstico do comprometimento cardíaco para pacientes com amiloidose foram 0,93 e 0,84, respectivamente. As curvas ROC também sugeriram uma validade diagnóstica alta do NT-proBNP com AUC de 0,95. Um nomograma de Fagan demonstrou que as probabilidades de NT-proBNP positivo e negativo no avanço do comprometimento por AC eram de 90% e 8%, respectivamente. O gráfico de funil de Deek não sugeriu viés significativo de publicação entre os estudos incluídos, e os resultados foram estáveis e confiáveis.

Conclusões

O NT-proBNP desempenha um papel positivo no diagnóstico precoce do comprometimento por AC, com alta sensibilidade e especificidade.

A Risk Score to Diagnose Cardiac Involvement and Provide Prognosis Information in Patients at Risk of Cardiac Light-Chain Amyloidosis

Background

Cardiac light-chain amyloidosis (AL CA) portends poor prognosis. Contrast cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) imaging is an important tool in recognizing AL CA. But contraindications to contrast CMR would significantly restrict its clinical application value. Our study aims to construct a convenient risk score to help identify cardiac involvement in patients at risk of AL CA. Moreover, we also investigate whether this risk score could provide prognosis information.

Materials and Methods

Sixty-three patients at risk of AL CA were retrospectively included in our study. Basic clinical characters, lab results, 12-lead electrocardiogram data, and cardiac magnetic resonance image data were collected. AL CA was diagnosed according to typical CA LGE pattern. Logistic analysis was used to figure out predictive parameters of AL CA and their β coefficients, further constructing the risk score. Receiver operating characteristics (ROC) curve was used to find the cut-off point best distinguishing AL CA+ from AL CA–patients. Bootstrapping was used for internal validation. All patients were divided into high-risk and low-risk group according to the diagnostic cut-off point, and followed up for survival information. Kaplan-Meier plots and log-rank test were performed to analyze if this score had prognostic value.

Results

The risk score finally consisted of 4 parameters: pericardial effusion (PE) (1 point), low electrocardiographic QRS voltages (LQRSV) (1 point), CMR-derived impaired global radial strain (GRS) (<15.14%) (1 point) and increased left ventricular maximum wall thickness (LVMWT) (>13 mm) (2 points). Total score ranged from 0 to 5 points. A cut-off point of 1.5 showed highest accuracy in diagnosing AL CA with an AUC of 0.961 (95% CI: 0.924–0.997, sensitivity: 90.6%, specificity: 83.9%). Kaplan-Meier plots and log-rank test showed that the high-risk group had significantly poor overall survival rates.

Conclusion

In patients at risk of AL CA, a risk score incorporating the presence of PE, LQRSV, and CMR-derived impaired GRS and increased LVMWT is predictive of a diagnosis of AL CA by LGE criteria. This risk score may be helpful especially when contrast CMR is not available or contraindicated, and further studies should be considered to validate this score.

Prevalence and determinants of iron deficiency in cardiac amyloidosis

Aims

Iron deficiency (ID) is common in patient with chronic heart failure (HF) and has been widely studied. In contrast, data concerning ID in cardiac amyloidosis (CA) are limited. Amyloidosis is a severe and fatal systemic disease, characterized by an accumulation of amyloid fibrils in various tissues/organs, including nerves, kidneys, gastrointestinal tract, and heart. Amyloid deposits in the heart eventually cause HF. The main subtypes of CA are light chain (AL), hereditary transthyretin (ATTRv), and wild‐type transthyretin (ATTRwt). We performed this study to determine the prevalence, clinical outcome (all‐cause mortality), and determinants of ID among the three main subtypes of CA.

Methods and results

Iron deficiency status were analysed in 816 CA patients enrolled at the French Referral Centre for Cardiac Amyloidosis: 271 (33%) had AL, 164 (20%) ATTRv, and 381 (47%) ATTRwt. ID affected 49% of CA patients, 45% with AL, 58% with ATTRv, and 48% with ATTRwt. We identified ATTR status (ATTRv P = 0.003, ATTRwt P = 0.037), diabetes (P = 0.003), aspirin treatment (P = 0.009), haemoglobin levels (P = 0.006), and altered global longitudinal strain (P = 0.02) as independent ID determinants. There is no difference in all‐cause mortality considering ID status.

Conclusions

Iron deficiency is common in patients with CA, irrespective of the subtype. Patients seem more likely to have ID if diagnosed with ATTR, if diabetic, and/or treated with aspirin. In CA, the benefit of intravenous iron therapy, for ID, on morbidity and mortality needs further study.

Diagnostic Work-Up of Cardiac Amyloidosis Using Cardiovascular Imaging: Current Standards and Practical Algorithms

Among non-ischemic cardiomyopathies, cardiac amyloidosis is one of the most common, being caused by extracellular depositions of amyloid fibrils in the myocardium. Two main forms of cardiac amyloidosis are known so far, including 1) light-chain (AL) amyloidosis caused by monoclonal production of light-chains, and 2) transthyretin (ATTR) amyloidosis, caused by dissociation of the transthyretin tetramer into monomers. Both AL and ATTR amyloidosis are progressive diseases with median survival from diagnosis of less than 6 months and 3 to 5 years, respectively, if untreated. In this regard, death occurs in most patients due to cardiac causes, mainly congestive heart failure, which can be prevented due to the presence of effective, life-saving treatment regimens. Therefore, early diagnosis of cardiac amyloidosis is crucial more than ever. However, diagnosis of cardiac amyloidosis may be challenging due to variable clinical manifestations and the perceived rarity of the disease. In this regard, clinical and laboratory reg flags are available, which may help clinicians to raise suspicion of cardiac amyloidosis. In addition, advances in cardiovascular imaging have already revealed a higher prevalence of cardiac amyloidosis in specific populations, so that the diagnosis especially of ATTR amyloidosis has experienced a >30-fold increase during the past ten years. The goal of our review article is to summarize these findings and provide a practical approach for clinicians on how to use cardiovascular imaging techniques, such as echocardiography, cardiac magnetic resonance, bone scintigraphy and, if required, organ biopsy within predefined diagnostic algorithms for the diagnostic work-up of patients with suspected cardiac amyloidosis. In addition, two clinical cases and practical tips are provided in this context.

History of extracardiac/cardiac events in cardiac amyloidosis: prevalence and time from initial onset to diagnosis

Aims

Cardiac amyloidosis (CA) has a poor prognosis which is aggravated by diagnostic delay. Amyloidosis extracardiac and cardiac events (AECE and ACE) may help improve CA diagnosis and typing. The aim of this study was to compare AECE and ACE between different CA types and assess their relationship with survival.

Methods and results

This retrospective cohort study conducted in France from June 2008 to May 2019, at the Henry Mondor Hospital. This cohort included 983 patients with CA. Mean age at inclusion was 73.1 ± 11.4 years, 726 (75.1%) were male and the mean body mass index was 24.5 ± 4.1 kg/m². Among them, 321 had immunoglobulin light chain (AL) amyloidosis, 434 had wild‐type transthyretin (ATTRwt), and 212 had hereditary transthyretin (ATTRv). The first AECE and/or ACE occurred at a mean age of 63 ± 11 years for AL and ATTRv, and 70 ± 12 years for ATTRwt (P < 0.01). The median (Q1–Q3) delay between declaration of the first events and diagnosis varied from 11.1 (5.9; 34.8) months for AL to 92.2 (39.0; 174.7) months for ATTRwt (P < 0.01). The nature of the onset of AECE or ACE varied based on amyloidosis type, heart failure symptoms for AL (26%) and integumentary symptoms for ATTRv with cardiologic or mixed phenotype (39%) and ATTRwt (42%). In AL and ATTRwt, a short delay between the onset of the first AECE or ACE and diagnosis was associated with reduced survival rate (log‐rank test P‐value <0.01).

Conclusions

This study highlights the impact of amyloidosis type and evolution on diagnostic delay and on prognosis. Physicians must be aware and vigilant in front of extracardiac and cardiac events to considerably improve early diagnosis of amyloidosis.

Prognostic value of left atrial strain in patients with wild-type transthyretin amyloid cardiomyopathy

Aims

This study was performed to investigate whether left atrial (LA) strain by echocardiography provides prognostic information in patients with wild‐type transthyretin amyloid cardiomyopathy (ATTRwt‐CM).

Methods and results

Among 129 patients who were diagnosed with ATTRwt‐CM at Kumamoto University Hospital from December 2002 to December 2019, 113 patients who had enough information for two‐dimensional speckle tracking echocardiography were enrolled in this study. During a median follow‐up of 668 days, 28 cardiovascular deaths occurred. Compared with patients in the non‐event group, those in the cardiovascular death group were significantly older (81.5 ± 7.4 vs. 78.1 ± 6.1 years, P < 0.01), had a lower incidence of carpal tunnel syndrome (21% vs. 47%, P < 0.05), and had a higher high‐sensitivity cardiac troponin T [0.085 (0.063–0.105) vs. 0.049 (0.036–0.079) ng/mL, P < 0.01] and B‐type natriuretic peptide concentrations [419 (239–541) vs. 271 (155–462) pg/mL, P < 0.01] and lower estimated glomerular filtration rate (41.8 ± 15.4 vs. 53.4 ± 14.6 mL/min/1.73 m², P < 0.01). Electrocardiography showed higher rate of a V1–V3 QS pattern (52% vs. 24%, P < 0.01) and complete left bundle branch block (27% vs. 6%, P < 0.01), and echocardiography showed a significantly lower peak LA strain rate during the contraction phase (0.16 ± 0.13 vs. 0.28 ± 0.27 S⁻¹, P < 0.05), LA strain during the reservoir phase (LASr) (5.84 ± 2.41 vs. 8.22 ± 4.05%, P < 0.01), and peak LA strain rate during the reservoir phase (0.26 ± 0.09 vs. 0.33 ± 0.15 S⁻¹, P < 0.05) in the cardiovascular death group than in non‐event group. By contrast, conventional echocardiographic findings were not significantly different between these two groups. After adjusting for conventional predictive factors of ATTRwt‐CM (age, high‐sensitivity cardiac troponin T and B‐type natriuretic peptide concentrations, and estimated glomerular filtration rate), multivariable Cox proportional hazard analyses showed that LASr was significantly and independently associated with cardiovascular death in patients with ATTRwt‐CM (odds ratio, 0.84; 95% confidence interval, 0.72–0.98; P < 0.05). After adjusting for age and echocardiographic findings associated with cardiovascular death (LA volume index and peak LA strain rate during the contraction phase), LASr was significantly and independently associated with cardiovascular death in patients with ATTRwt‐CM (odds ratio, 0.83; 95% confidence interval, 0.70–0.98; P < 0.05). Receiver operating characteristic curve analysis showed that the area under the curve of LASr for cardiovascular death was 0.686 and that the best cut‐off value of LASr was 6.69% (sensitivity, 62.4%; specificity, 64.3%). In the Kaplan–Meier analysis, patients with low LASr (<6.69%) had a significantly higher probability of total cardiovascular death (P < 0.05) and heart failure‐related hospitalization (P < 0.05).

Conclusions

Left atrial strain during the reservoir phase provides significant prognostic value in patients with ATTRwt‐CM even after adjusting for conventional predictive factors.

A descriptive study of transthyretin amyloidosis in a tertiary hospital without a referral unit

BACKGROUND AND OBJECTIVE

Transthyretin amyloidosis (ATTR) is a rare disease that is part of systemic amyloidosis and is life-threatening. It can affect all organs and systems, the most frequent being neurological and cardiac involvement. This study aims to detect possible ATTR cases and carry out a descriptive study of them.

MATERIAL AND METHODS

Descriptive single-centre study carried out in a tertiary hospital, which included patients with suspected ATTR between September 2016 and January 2020.

RESULTS

A total of 190 suspected ATTR patients were detected. The study includes 100 of these patients, as well as 10 relatives of patients in whom ATTR was detected in its genetic variant (ATTRv). In total, ATTRv was detected in 7 individuals (3 with a presymptomatic mutation of the disease), 16 patients with age-related ATTR and 31 individuals with unknown cardiac amyloidosis with the tests performed, which confirms the presence of this disease in non-endemic areas.

CONCLUSIONS

ATTR is a disease that must be taken into account in the differential diagnosis of patients with heart failure with preserved LVEF, especially if associated with neurological symptoms.

Transthyretin cardiac amyloidosis: a review of the nuclear imaging findings with emphasis on the radiotracers mechanisms

Cardiac amyloidosis is a protein deposition disease characterized by the infiltration of the myocardium and coronary arteries resulting in a progressive thickening of both ventricles, interatrial septum and atrioventricular valves, eventually leading to organ failure. It is a disease hard to diagnose, due to the lack of diagnostic investigations. However, development of new and more accurate examinations is undergoing. Endomyocardial biopsy is the gold standard investigation for this disease, but it has its limitations (invasive and not widely available). Other investigations may be able to detect the presence of cardiac amyloidosis but cannot specify the type involved. To that end, nuclear medicine through bone scanning offers a simple, non-invasive solution to detect, differentiate and diagnose transthyretin cardiac amyloidosis (ATTR) from other types of cardiac amyloidosis. In order to demonstrate the importance of bone scanning we will present a few methods of image processing based on literature and a personalized method, followed by a few important examples of positive cases. The aim of this review was to present the current methods of ATTR detection with emphasis on nuclear medicine bone scanning and its important place in the decision algorithm of the cardiologist for a personalized approach to this pathology.

Variable Presentation of Hereditary Transthyretin-Mediated Amyloidosis at a Single Center

OBJECTIVES

Describe atypical presentations of hereditary transthyretin-mediated (hATTR) amyloidosis with polyneuropathy.

METHODS

Initial symptoms, diagnoses, and follow-up were recorded at the Austin Neuromuscular Center for 12 patients with nonclassical presentation of hATTR amyloidosis.

RESULTS

Common initial symptoms were hand and/or feet sensory manifestations (83%), muscle weakness (58%), and, less frequently, gastrointestinal and orthostatic impairment and carpal tunnel syndrome. Initial diagnoses were polyneuropathy (83%) and/or myopathy (25%). During follow-up, 10 patients (83%) developed cardiac symptoms (dyspnea, 67% and ankle edema, 17%), resulting in revised diagnoses of heart disease. Multisystem involvement raised suspicion of amyloidosis, which was confirmed by biopsy or nuclear scintigraphy, and genetic testing. All patients had polyneuropathy; 8 (67%) had cardiomyopathy-associated transthyretin mutations (V122I or T60A). Time from symptom onset to diagnosis was up to 10 years (median 5 years), during which patients' health deteriorated, although with recognition of disease signs/symptoms the diagnosis of hATTR amyloidosis was made in approximately 2-6 months from presentation at our center.

CONCLUSIONS

Increased awareness of the diverse initial hATTR amyloidosis symptoms could shorten time to diagnosis, enabling earlier treatment and improved patient outcomes.

18F-sodium fluoride PET/MRI myocardial imaging in patients with suspected cardiac amyloidosis

BACKGROUND

We evaluated the diagnostic performance of 18F-NaF PET/MRI in patients with suspected cardiac amyloidosis (CA).

METHODS

Twenty-seven consecutive patients underwent myocardial PET 1 hour after injection of 4 MBq/kg 18F-NaF with simultaneous MRI including cine-MRI, T1 and T2 mapping, first-pass and late gadolinium enhancement (LGE). 18F-NaF uptake was measured visually and semi-quantitatively by calculating myocardium-to-blood pool (M/B) ratios. CA was confirmed histologically.

RESULTS

Transthyretin (TTR)-CA was diagnosed in 16 patients, light-chain (AL)-CA in 7, and no-CA in 4. Visual interpretation of 18F-NaF images revealed a relative increase in myocardial uptake in only 3 patients, all with TTR CA, and a relative decrease in 13, including 7 AL CA, 3 no-CA, and 3 TTR CA. M/B ratios were significantly higher in TTR CA (1.00 ± 0.12) than in AL CA (0.81 ± 0.06, P = 0.001) or in no-CA (0.73 ± 0.16, P = 0.006). The optimal M/B cut-off to distinguish TTR CA from AL CA was ≥ 0.90 (Fischer, P = 0.0005). By comparison, classification of patients using 99mTc-HMDP heart-to-mediastinum ratios with the previously published cut-off ≥ 1.21 reached higher significance (P < 0.0001). Among MRI parameters, myocardial T1, LGE score, and extracellular volume were higher in CA than in no-CA patients, 1409 ± 76 vs 1278 ± 35 ms (P = 0.004), 10.35 ± 5.30 vs 3.50 ± 3.42 (P = 0.03), and 46 ± 10 vs 33 ± 8 % (P = 0.01), respectively.

CONCLUSION

18F-NaF PET/MRI shows good diagnostic performance when semi-quantification is used. However, contrast is low and visual interpretation may be challenging in routine. PET/MRI could constitute a one-stop-shop evaluation of amyloid load and cardiac function in patients needing rapid work-up.

Cardiac amyloid presenting as cardiogenic shock: case series

Background

Amyloidosis is a systemic infiltrative disease that can affect nearly every organ in the human body. It is characterized by the deposition of misfolded protein within various tissues and organs. Once there is cardiac involvement this portends a worse prognosis.

Case summary

We describe a case series of two patients with cardiac amyloidosis presenting as a cardiogenic shock. There were several missed opportunities in diagnosing cardiac amyloid prior to their fatal presentations. In the first case, a 65-year-old African-American male patient presented with worsening shortness of breath and signs of heart failure. Echocardiography revealed preserved ejection fraction. He was diagnosed with light chain subtype of cardiac amyloidosis, and rapidly deteriorated during his admission. Patient in the second case is a 75-year-old African-American female who presented with worsening heart failure and hypotension. Echocardiography revealed reduced ejection fraction. She was diagnosed with transthyretin cardiac amyloid. Her clinical status worsened during admission and she went into cardiogenic shock requiring multiple vasopressors.

Discussion

This case series discusses two incidences of cardiac amyloidosis presenting as cardiogenic shock in African-American patients. This article postulates that cardiac amyloidosis may be misdiagnosed for more common causes of heart failure especially among this demographic group. Once patients with cardiac amyloid present with cardiogenic shock their clinical course is typically rapidly fatal despite aggressive measures. Earlier detection is imperative to prevent poor outcomes.

Search for AL amyloidosis risk factors using Mendelian randomization

In amyloid light chain (AL) amyloidosis, amyloid fibrils derived from immunoglobulin light chain are deposited in many organs, interfering with their function. The etiology of AL amyloidosis is poorly understood. Summary data from genome-wide association studies (GWASs) of multiple phenotypes can be exploited by Mendelian randomization (MR) methodology to search for factors influencing AL amyloidosis risk. We performed a 2-sample MR analyzing 72 phenotypes, proxied by 3461 genetic variants, and summary genetic data from a GWAS of 1129 AL amyloidosis cases and 7589 controls. Associations with a Bonferroni-defined significance level were observed for genetically predicted increased monocyte counts (P = 3.8 × 10-4) and the tumor necrosis factor receptor superfamily member 17 (TNFRSF17) gene (P = 3.4 × 10-5). Two other associations with the TNFRSF (members 6 and 19L) reached a nominal significance level. The association between genetically predicted decreased fibrinogen levels may be related to roles of fibrinogen other than blood clotting. be related to its nonhemostatic role. It is plausible that a causal relationship with monocyte concentration could be explained by selection of a light chain-producing clone during progression of monoclonal gammopathy of unknown significance toward AL amyloidosis. Because TNFRSF proteins have key functions in lymphocyte biology, it is entirely plausible that they offer a potential link to AL amyloidosis pathophysiology. Our study provides insight into AL amyloidosis etiology, suggesting high circulating levels of monocytes and TNFRSF proteins as risk factors.

Heart failure following transcatheter aortic valve replacement

Introduction: Over the past decade, the number of transcatheter aortic valve replacement (TAVR) procedures has increased exponentially. Despite major improvements in both device and successes, the rate of hospital readmission after TAVR remains high, with heart failure (HF) decompensation being one of the most important causes.Areas covered: This review provides an overview of the current status of HF following TAVR, including details about its incidence, clinical impact, contributing factors, and current and future treatment perspectives.Expert opinion: HF decompensation has been identified as the most common cause of rehospitalization following TAVR, and it has been associated with a negative prognosis. Multiple preexisting factors including low flow status, cardiac amyloidosis, myocardial fibrosis, multivalvular disease, pulmonary hypertension, coronary artery disease, and atrial fibrillation have been associated with an increased risk of HF events. Also, multiple post-procedural factors like the occurrence of significant paravalvular leaks, severe prosthesis-patient mismatch, and conduction disturbances have also contributed to increase this risk . Thus, reducing HF events in TAVR recipients would require a multifactorial and multidisciplinary effort including the optimization of the medical treatment and close follow-up and treatment of residual or concomitant valvular disease and conduction disturbance issues. Future studies in this challenging group of patients are warranted.

Cardiac Magnetic Resonance Predicting Outcomes Among Patients at Risk for Cardiac AL Amyloidosis

Introduction: Patients with systemic AL amyloidosis (AL) should be evaluated for cardiac amyloidosis (CA), as prognosis is strongly related to cardiac involvement. We assessed the characteristics of patients referred to cardiac magnetic resonance (CMR) with suspected CA from a cancer center and determine predictors of mortality/heart failure hospitalizations (HFH).

Methods: Forty-four consecutive patients referred for CMR with suspected CA were retrospectively included. Variables collected included cardiac biomarkers, in addition to echocardiographic and CMR variables. Survival analyses were performed to determine which variables were more predictive of mortality and HFH.

Results: Of the 44 patients included, 55% were females. 73% of patients were diagnosed with CA by CMR; 56% of them had an established diagnosis of AL. Patients with CA by CMR had higher native T1, higher extracellular volume (ECV) fraction, higher T2, less negative GLS by Echo, and higher troponin I and B-type natriuretic peptide (BNP). Kaplan-Meier survival analysis revealed that the following were predictive of mortality: an ECV ≥ 0.50 (p = 0.0098), CMR LVEF < 50% (p = 0.0010), T2/ECV ≤ 100 (p = 0.0001), and troponin I > 0.03 (p = 0.0025). In a stepwise conditional Cox logistic regression model, the only variable predictive of a composite of mortality and HFH was ECV (HR: 1.17, 95% CI = 1.02–1.34 p = 0.030).

Conclusion: ECV seems to be an important biomarker that could be a predictor of outcomes in cardiac AL amyloidosis. In combination, CMR and serum cardiac biomarkers might help to establish prognosis in patients with CA.

Diagnostic score of cardiac involvement in AL amyloidosis

AIMS

Early diagnosis of cardiac involvement is a key issue in the management of AL amyloidosis. Our objective was to establish a diagnostic score of cardiac involvement in AL amyloidosis and to compare it with the current consensus criteria [i.e. left ventricular hypertrophy >12 mm and N-terminal pro b-type natriuretic peptide (NT-proBNP) >332 ng/L].

METHODS AND RESULTS

We carried out a prospective and multicenter study on AL amyloidosis patients who underwent cardiac evaluation including clinical examination, electrocardiography (ECG), cardiac biomarkers, transthoracic echocardiography (TTE), and cardiac magnetic resonance imaging (CMR). Cardiac involvement was based on CMR and/or endomyocardial biopsy. In a derivation cohort of 114 patients (82 with cardiac involvement), the highest diagnostic accuracy was observed with NT-proBNP and troponin blood levels, TTE-derived global longitudinal strain (LS), and apical to basal LS gradient. By using multivariate analysis, we established a diagnostic score including global LS ≥-17% (1 point), apical/(basal + median) LS ≥0.90 (1 point), and troponin T >35 ng/L (1 point). A score >1 was associated with sensitivity of 94% and specificity of 97%, an area under the curve of 0.98 [95% confidence interval (CI) 0.93-0.99] as well as a net reclassification index of 0.39 (95% CI 0.28-0.46) when compared with consensus criteria. In a validation cohort of 73 AL amyloidosis patients, the area under the receiver operating characteristic curve of the diagnostic score was 0.97 (95% CI 0.90-0.99).

CONCLUSION

Combining T troponin blood levels and two echo-derived strain parameters leads to very high accuracy for diagnosing cardiac involvement in AL amyloid patients.

Association of the transthyretin variant V122I with polyneuropathy among individuals of African ancestry

Hereditary transthyretin-mediated (hATTR) amyloidosis is an underdiagnosed, progressively debilitating disease caused by mutations in the transthyretin (TTR) gene. V122I, a common pathogenic TTR mutation, is found in 3-4% of individuals of African ancestry in the United States and has been associated with cardiomyopathy and heart failure. To better understand the phenotypic consequences of carrying V122I, we conducted a phenome-wide association study scanning 427 ICD diagnosis codes in UK Biobank participants of African ancestry (n = 6062). Significant associations were tested for replication in the Penn Medicine Biobank (n = 5737) and the Million Veteran Program (n = 82,382). V122I was significantly associated with polyneuropathy in the UK Biobank (odds ratio [OR] = 6.4, 95% confidence interval [CI] 2.6-15.6, p = 4.2 × 10-5), which was replicated in the Penn Medicine Biobank (OR = 1.6, 95% CI 1.2-2.4, p = 6.0 × 10-3) and Million Veteran Program (OR = 1.5, 95% CI 1.2-1.8, p = 1.8 × 10-4). Polyneuropathy prevalence among V122I carriers was 2.1%, 9.0%, and 4.8% in the UK Biobank, Penn Medicine Biobank, and Million Veteran Program, respectively. The cumulative incidence of common hATTR amyloidosis manifestations (carpal tunnel syndrome, polyneuropathy, cardiomyopathy, heart failure) was significantly enriched in V122I carriers compared with non-carriers (HR = 2.8, 95% CI 1.7-4.5, p = 2.6 × 10-5) in the UK Biobank, with 37.4% of V122I carriers having at least one of these manifestations by age 75. Our findings show that V122I carriers are at increased risk of polyneuropathy. These results also emphasize the underdiagnosis of disease in V122I carriers with a significant proportion of subjects showing phenotypic changes consistent with hATTR amyloidosis. Greater understanding of the manifestations associated with V122I is critical for earlier diagnosis and treatment.

Cardiac amyloidosis in non-transplant cardiac surgery

Cardiac amyloidosis is a rare infiltrative cardiomyopathy that portends a poor prognosis. There is a growing recognition of co-existent aortic valve stenosis and transthyretin cardiac amyloidosis, with some studies suggesting that dual pathology may be associated increased risk of complication and mortality during surgical intervention. This review aims to evaluate the available literature on non-transplant cardiac surgical interventions in patients with cardiac amyloidosis, with particular focus on diagnosis, high surgical risk and areas of uncertainty that require further research.

AL type cardiac amyloidosis: a devastating fatal disease

Introduction

Cardiac amyloidosis is a rare entity with a grave prognosis. Due to the low index of suspicion secondary to non-specific symptoms, it is often diagnosed at an advanced stage with multi-organ involvement.

Methods

We report a case of systemic AL amyloidosis with predominant cardiac and renal involvement associated with multiple myeloma.

Case Summary

A 60-year-old male presented with progressive anasarca, orthopnea and weight gain over 8 months. On clinical examination, 3+ pitting edema was found in bilateral extremities and scrotum. Serum N-type proBNP and troponin T were elevated, and EKG showed diffuse low voltage QRS, right axis deviation, and 1^st degree AV block. Echocardiography revealed granular myocardium, biventricular hypertrophy, bi-atrial dilation and apical sparing pattern on global longitudinal strain which was suggestive of cardiac amyloidosis. Light chain assessment showed elevated kappa and lambda chains with kappa to lambda ratio of 16.2. Endomyocardial biopsy revealed AL type cardiac amyloidosis, and bone marrow biopsy confirmed the diagnosis of multiple myeloma. He received six cycles of bortezomib, cyclophosphamide, and dexamethasone but continued to deteriorate. He experienced an episode of cardiac arrest following which he had a return of spontaneous circulation but due to poor prognosis, the family opted for pursuing comfort measures only.

Conclusions

Cardiac involvement in AL type amyloidosis imparts significant morbidity and mortality. The management of cardiac amyloidosis entails a multidisciplinary approach with an emphasis on cardiology and oncology. Despite the novel diagnostic modalities and treatment regimens, the outcome for AL-type cardiac amyloidosis remains poor.