The Most Predictive Red Flags for Suspecting Cardiac Amyloidosis in Patients with Heart Failure with Preserved Ejection Fraction.

OBJECTIVE: Cardiac amyloidosis (CA) is a cardiomyopathy characterized by amyloid infiltration in the myocardium. Transthyretin cardiac amyloidosis (TTR-CA), commonly presenting as heart failure with preserved ejection fraction (HFpEF), was the focus of our study, which aimed to identify red flags that heighten suspicion of CA in HFpEF patients. METHODS: We prospectively included patients diagnosed with HFpEF. All patients were assessed for TTR-CA red flag features, cardiac and extra-cardiac, as outlined in the 'Diagnosis and Treatment of Cardiac Amyloidosis: A Position Statement of the European Society of Cardiology.' Technetium-99m pyrophosphate (99mTc-PYP) cardiac scintigraphy was performed in 167 HFpEF patients suspected of having TTR-CA. Patients testing positive and negative for TTR-CA were compared based on these red flag features. RESULTS: Out of 167 HFpEF patients, 19 (11.3%) were diagnosed with TTR-CA. In the TTR-CA group, 17 (89.5%) patients were 65 years or older. The presence of three or more red flags differentiated the TTR-CA positive and negative groups (P = 0.040). Features such as low voltage and pseudo infarct patterns were more prevalent in the TTR-CA group (P < 0.001 and P < 0.048, respectively). Left ventricular global longitudinal strain (LV-GLS) was lower in the TTR-CA positive group (P < 0.001). Multivariate analysis identified four variables-older age, pseudo infarct pattern, low/decreased QRS voltage, and LV-GLS-as strong, independent predictors of TTR-CA, with significant odds ratios (ORs) of 7.8, 6.8, 16.9, and 1.2, respectively. CONCLUSION: In this study, TTR-CA etiology occurs in approximately one in every ten HFpEF patients. The presence of three or more red flags increases the likelihood of TTR-CA. Older age, pseudo infarct pattern, low/decreased QRS voltage, and reduced LV-GLS are the most significant red flags indicating TTR-CA in HFpEF patients.

Predictors of developing renal dysfunction following diagnosis of transthyretin cardiac amyloidosis.

BACKGROUND: In patients with transthyretin cardiac amyloidosis (ATTR-CA), renal dysfunction is a poor prognostic indicator. Limited data are available on variables that portend worsening renal function (wRF) among ATTR-CA patients. OBJECTIVES: This study assesses which characteristics place patients at higher risk for the development of wRF (defined as a drop of ≥10% in glomerular filtration rate [GFR]) within the first year following diagnosis of ATTR-CA. METHODS: We included patients with ATTR-CA (n = 134) evaluated between 2/2016 and 12/2022 and followed for up to 1 year at our amyloid clinic. Patients were stratified into two groups: a group with maintained renal function (mRF) and a group with wRF and compared using appropriate testing. Significant variables in the univariate analysis were included in the multivariable logistic regression model to determine characteristics associated with wRF. RESULTS: Within a follow-up period of 326 ± 118 days, the median GFR% change measured -6% [-18%, +8]. About 41.8% (n = 56) had wRF, while the remainder had mRF. In addition, in patients with no prior history of chronic kidney disease (CKD), 25.5% developed de novo CKD. On multivariable logistic regression, only New York Heart Association (NYHA) class ≥III (odds ratio [OR]: 3.9, 95% confidence interval [CI]: [1.6-9.3]), history of ischemic heart disease (IHD) (OR: 0.3, 95% CI: [0.1-0.7]), and not receiving SGLT-2i (OR: 0.1, 95% CI: [0.02-0.5]) were significant predictors of wRF. CONCLUSION: Our study demonstrated that the development of de novo renal dysfunction or wRF is common following the diagnosis of ATTR-CA. Additionally, we identified worse NYHA class and no prior history of IHD as significant predictors associated with developing wRF, while receiving SGLT-2i therapy appeared to be protective in this population.

Gait abnormalities in older adults with transthyretin cardiac amyloidosis.

BACKGROUND: Transthyretin cardiac amyloidosis (ATTR cardiac amyloidosis) is caused by variant (ATTRv) or wild type (ATTRwt) transthyretin. While gait abnormalities have been studied in younger patients with ATTRv amyloidosis, research on gait in older adults with ATTR cardiac amyloidosis is lacking. Given ATTR cardiac amyloidosis' association with neuropathy and orthopedic manifestations, we explore the gait in this population. METHODS: Twenty-eight older male ATTR cardiac amyloidosis patients and 11 healthy older male controls walked overground with and without a dual cognitive task. Gait parameters: stride width, length, velocity and stance time percentage were measured using an instrumented mat. ATTR amyloidosis patients were further categorized based on clinical and functional assessments. RESULTS: We found significant gait differences between ATTR cardiac amyloidosis patients and healthy controls; patients had more variable, slower, narrower and shorter strides, with their feet spending more time in contact with the ground as opposed to in swing. However, the observed gait differences did not correlate with clinical and functional measures of ATTR cardiac amyloidosis severity. CONCLUSIONS: Our results suggest that gait analysis could be a complementary tool for characterizing ATTR cardiac amyloidosis patients and may inform clinical care as it relates to falls, management of anticoagulation, and functional independence.

Myocardial perfusion in cardiac amyloidosis.

AIMS: Cardiac involvement is the main driver of clinical outcomes in systemic amyloidosis and preliminary studies support the hypothesis that myocardial ischaemia contributes to cellular damage. The aims of this study were to assess the presence and mechanisms of myocardial ischaemia using cardiovascular magnetic resonance (CMR) with multiparametric mapping and histopathological assessment. METHODS AND RESULTS: Ninety-three patients with cardiac amyloidosis (CA) (light-chain amyloidosis n = 42, transthyretin amyloidosis n = 51) and 97 without CA (three-vessel coronary disease [3VD] n = 47, unobstructed coronary arteries n = 26, healthy volunteers [HV] n = 24) underwent quantitative stress perfusion CMR with myocardial blood flow (MBF) mapping. Twenty-four myocardial biopsies and three explanted hearts with CA were analysed histopathologically. Stress MBF was severely reduced in patients with CA with lower values than patients with 3VD, unobstructed coronary arteries and HV (CA: 1.04 ± 0.51 ml/min/g, 3VD: 1.35 ± 0.50 ml/min/g, unobstructed coronary arteries: 2.92 ± 0.52 ml/min/g, HV: 2.91 ± 0.73 ml/min/g; CA vs. 3VD p = 0.011, CA vs. unobstructed coronary arteries p < 0.001, CA vs. HV p < 0.001). Myocardial perfusion abnormalities correlated with amyloid burden, systolic and diastolic function, structural parameters and blood biomarkers (p < 0.05). Biopsies demonstrated abnormal vascular endothelial growth factor staining in cardiomyocytes and endothelial cells, which may be related to hypoxia conditions. Amyloid infiltration in intramural arteries was associated with severe lumen reduction and severe reduction in capillary density. CONCLUSION: Cardiac amyloidosis is associated with severe inducible myocardial ischaemia demonstrable by histology and CMR stress perfusion mapping. Histological evaluation indicates a complex pathophysiology, where in addition to systolic and diastolic dysfunction, amyloid infiltration of the epicardial arteries and disruption and rarefaction of the capillaries play a role in contributing to myocardial ischaemia.

Atrial function and geometry differences in transthyretin versus immunoglobulin light chain amyloidosis: a cardiac magnetic resonance study.

To determine the differences in left atrial (LA) function and geometry assessed by cardiac magnetic resonance (CMR) between transthyretin (ATTR) and immunoglobulin light chain (AL) cardiac amyloidosis (CA). We performed a retrospective analysis of 54 consecutive patients (68.5% male, mean age 67 ± 11 years) with confirmed CA (24 ATTR, 30 AL) who underwent comprehensive CMR examinations. LA structural and functional assessment including LA volume, LA sphericity index, and LA strain parameters were compared between both subtypes. In addition, 15 age-matched controls were compared to all groups. Patients with ATTR-CA were older (73 ± 9 vs. 62 ± 10 years, p < 0.001) and more likely to be male (83.3% vs. 56.7%, p = 0.036) when compared to AL-CA. No significant difference existed in LA maximum volume and LA sphericity index between ATTR-CA and AL-CA. LA minimum volumes were larger in ATTR-CA when compared with AL-CA. There was a significant difference in LA function with worse strain values in ATTR vs AL: left atrial reservoir [7.4 (6.3-12.8) in ATTR vs. 13.8 (6.90-24.8) in AL, p = 0.017] and booster strains [3.6 (2.6-5.5) in ATTR vs. 5.2 (3.6-12.1) in AL, p = 0.039]. After adjusting for age, LA reservoir remained significantly lower in ATTR-CA compared to AL-CA (p = 0.03), but not LA booster (p = 0.16). We demonstrate novel differences in LA function between ATTR-CA and AL-CA despite similar LA geometry. Our findings of more impaired LA function in ATTR may offer insight into higher AF burden in these patients.

Misconceptions and Facts About Cardiac Amyloidosis.

Cardiac amyloidosis is an important clinical entity associated with significant morbidity and mortality. Although the signs and symptoms can be apparent early in the disease course, diagnoses are often made late because of inadequate recognition. A diagnosis of cardiac amyloidosis requires careful scrutiny of a patient's symptoms, an electrocardiogram, and imaging studies, including echocardiography and magnetic resonance imaging. Further evaluation is required through the measurement of serum and urine light chains and the use of bone scintigraphy imaging to differentiate transthyretin amyloidosis from light-chain cardiac amyloidosis. The available treatments have expanded tremendously in recent years and have improved outcomes in the population with this disorder. Thus, it has become increasingly important to diagnose cardiac amyloidosis and provide timely therapies. This article will clarify the various misconceptions about cardiac amyloidosis and provide a framework for primary care providers to better identify this disease in their practice.

In Vitro and In Vivo Effects of SerpinA1 on the Modulation of Transthyretin Proteolysis.

Transthyretin (TTR) proteolysis has been recognized as a complementary mechanism contributing to transthyretin-related amyloidosis (ATTR amyloidosis). Accordingly, amyloid deposits can be composed mainly of full-length TTR or contain a mixture of both cleaved and full-length TTR, particularly in the heart. The fragmentation pattern at Lys48 suggests the involvement of a serine protease, such as plasmin. The most common TTR variant, TTR V30M, is susceptible to plasmin-mediated proteolysis, and the presence of TTR fragments facilitates TTR amyloidogenesis. Recent studies revealed that the serine protease inhibitor, SerpinA1, was differentially expressed in hepatocyte-like cells (HLCs) from ATTR patients. In this work, we evaluated the effects of SerpinA1 on in vitro and in vivo modulation of TTR V30M proteolysis, aggregation, and deposition. We found that plasmin-mediated TTR proteolysis and aggregation are partially inhibited by SerpinA1. Furthermore, in vivo downregulation of SerpinA1 increased TTR levels in mice plasma and deposition in the cardiac tissue of older animals. The presence of TTR fragments was observed in the heart of young and old mice but not in other tissues following SerpinA1 knockdown. Increased proteolytic activity, particularly plasmin activity, was detected in mice plasmas. Overall, our results indicate that SerpinA1 modulates TTR proteolysis and aggregation in vitro and in vivo.

Prevalence of Transthyretin Amyloid Cardiomyopathy in Heart Failure With Preserved Ejection Fraction.

Importance: Heart failure (HF) with preserved ejection fraction (HFpEF) is common, is frequently associated with ventricular wall thickening, and has no effective therapy. Transthyretin amyloid cardiomyopathy (ATTR-CM) can cause the HFpEF clinical phenotype, has highly effective therapy, and is believed to be underrecognized. Objective: To examine the prevalence of ATTR-CM without and with systematic screening in patients with HFpEF and ventricular wall thickening. Design, Setting, and Participants: This population-based cohort study assessed ATTR-CM prevalence in 1235 consecutive patients in southeastern Minnesota with HFpEF both without (prospectively identified cohort study) and with (consenting subset of cohort study, n = 286) systematic screening. Key entry criteria included validated HF diagnosis, age of 60 years or older, ejection fraction of 40% or greater, and ventricular wall thickness of 12 mm or greater. In this community cohort of 1235 patients, 884 had no known ATTR-CM, contraindication to technetium Tc 99m pyrophosphate scanning, or other barriers to participation in the screening study. Of these 884 patients, 295 consented and 286 underwent scanning between October 5, 2017, and March 9, 2020 (community screening cohort). Exposures: Medical record review or technetium Tc 99m pyrophosphate scintigraphy and reflex testing for ATTR-CM diagnosis. Main Outcomes and Measures: The ATTR-CM prevalence by strategy (clinical diagnosis or systematic screening), age, and sex. Results: A total of 1235 patients participated in the study, including a community cohort (median age, 80 years; interquartile range, 72-87 years; 630 [51%] male) and a community screening cohort (n = 286; median age, 78 years; interquartile range, 71-84 years; 149 [52%] male). In the 1235 patients in the community cohort without screening group, 16 patients (1.3%; 95% CI, 0.7%-2.1%) had clinically recognized ATTR-CM. The prevalence was 2.5% (95% CI, 1.4%-4.0%) in men and 0% (95% CI, 0.0%-0.6%) in women. In the 286 patients in the community screening cohort, 18 patients (6.3%; 95% CI, 3.8%-9.8%) had ATTR-CM. Prevalence increased with age from 0% in patients 60 to 69 years of age to 21% in patients 90 years and older (P < .001). Adjusting for age, ATTR-CM prevalence differed by sex, with 15 of 149 men (10.1%; 95% CI, 5.7%-16.1%) and 3 of 137 women (2.2%; 95% CI, 0.4%-6.3%) having ATTR-CM (P = .002). Conclusions and Relevance: In this cohort study based in a community-based setting, ATTR-CM was present in a substantial number of cases of HFpEF with ventricular wall thickening, particularly in older men. These results suggest that systematic evaluation can increase the diagnosis of ATTR-CM, thereby providing therapeutically relevant phenotyping of HFpEF.

Quality of life assessment in amyloid transthyretin (ATTR) amyloidosis.

BACKGROUND: Amyloid transthyretin (ATTR) amyloidosis is caused by the systemic deposition of transthyretin molecules, either normal (wild-type ATTR, ATTRwt) or mutated (variant ATTR, ATTRv). ATTR amyloidosis is a disease with a severe impact on patients' quality of life (QoL). Nonetheless, limited attention has been paid to QoL so far, and no specific tools for QoL assessment in ATTR amyloidosis currently exist. QoL can be evaluated through patient-reported outcome measures (PROMs), which are completed by patients, or through scales, which are compiled by clinicians. The scales investigate QoL either directly or indirectly, i.e., by assessing the degree of functional impairment and limitations imposed by the disease. DESIGN: Search for the measures of QoL evaluated in phase 2 and phase 3 clinical trials on ATTR amyloidosis. RESULTS: Clinical trials on ATTR amyloidosis have used measures of general health status, such as the Short Form 36 Health Survey (SF-36), or tools developed in other disease settings such as the Kansas City Cardiomyopathy Questionnaire (KCCQ) or adaptations of other scales such as the modified Neuropathy Impairment Score +7 (mNIS+7). CONCLUSIONS: Scales or PROMs for ATTR amyloidosis would be useful to better characterize newly diagnosed patients and to assess disease progression and response to treatment. The ongoing ITALY (Impact of Transthyretin Amyloidosis on Life qualitY) study aims to develop and validate 2 PROMs encompassing the whole phenotypic spectrum of ATTRwt and ATTRv amyloidosis, that might be helpful for patient management and may serve as surrogate endpoints for clinical trials.

Hereditary transthyretin amyloidosis in mainland China: a unicentric retrospective study.

OBJECTIVE: This study aims to report the genotypes and phenotypes of hereditary transthyretin amyloidosis (ATTR) in a large Chinese cohort, yet the clinical and genetic profiles of ATTR remain elusive in mainland China. METHODS: Fifty-four patients with molecularly confirmed ATTR from 39 unrelated families were identified by sequencing the TTR gene. Sural nerve biopsies were performed in 40 of these cases. The clinical and electrophysiological data were retrospectively collected and analyzed. RESULTS: The male/female ratio was 42:12. The average age of patients at the onset of the disease was 47.8 ± 13.0 years. The late-onset type occurred in 29 cases (53.7%). Twenty-two probands (56.4%) had a family history with ATTR. The initial symptoms were limb paresthesia in 33 cases (61.1%), autonomic dysfunction in 15 cases (27.8%), and blurred vision in 6 cases (11.1%). A total of 22 different TTR mutations were identified, including Val30Met (25.6%) in 10 families in North China and Ala97Ser in 4 families (10.3%) in South China. Electrophysiological studies revealed general sensorimotor axonal polyneuropathy in 33/44 cases (75.0%), mixed neuropathy with axonal and demyelinating impairment features in 9/44 cases (20.5%) and isolated carpal tunnel syndrome in two cases. Sural nerve biopsies revealed positive Congo red staining in 16/40 cases (40.0%). CONCLUSION: Chinese patients with ATTR exhibited heterogeneous TTR genotypes and clinical phenotypes. Val30Met remains the most common mutation type in mainland China.

Impact of Tafamidis on Health-Related Quality of Life in Patients With Transthyretin Amyloid Cardiomyopathy (from the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial).

In the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial, tafamidis significantly reduced all-cause mortality and cardiovascular-related hospitalizations in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). ATTR-CM is associated with a significant burden of disease; further analysis of patient-reported quality of life will provide additional data on the efficacy of tafamidis. In the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial, 441 adult patients with ATTR-CM were randomized (2:1:2) to tafamidis 80 mg, tafamidis 20 mg, or placebo for 30 months, with pooled tafamidis (80 mg and 20 mg) compared with placebo. Change in Kansas City Cardiomyopathy Questionnaire Overall Summary (KCCQ-OS) domain scores, EQ-5D-3L scores, and patient global assessment, were prespecified exploratory end points. A greater proportion of patients improved KCCQ-OS score at month 30 with tafamidis (41.8%) versus placebo (21.4%). Tafamidis significantly reduced the decline in all 4 KCCQ-OS domains (p <0.0001 for all), and in EQ-5D-3L utility (0.09 [confidence interval 0.05 to 0.12]; p <0.0001) and EQ visual analog scale (9.11 [confidence interval 5.39 to 12.83]; p <0.0001) scores at month 30 versus placebo. A larger proportion of tafamidis-treated patients reported their patient global assessment improved at month 30 (42.3% vs 23.8% with placebo). In conclusion, tafamidis effectively reduced the decline in patient-reported outcomes, providing further insight into its efficacy in health-related quality of life in patients with ATTR-CM.

A multi-modal diagnostic model improves detection of cardiac amyloidosis among patients with diagnostic confirmation by cardiac biopsy.

BACKGROUND: Timely recognition of cardiac amyloidosis is clinically important, but the diagnosis is frequently delayed. OBJECTIVES: We sought to identify a multi-modality approach with the highest diagnostic accuracy in patients evaluated by cardiac biopsy, the diagnostic gold standard. METHODS: Consecutive patients (N = 242) who underwent cardiac biopsy for suspected amyloidosis within an 18-year period were retrospectively identified. Cardiac biomarker, ECG, and echocardiography results were examined for correlation with biopsy-proven disease. A prediction model for cardiac amyloidosis was derived using multivariable logistic regression. RESULTS: The overall cohort was characterized by elevated BNP (median 727 ng/mL), increased left ventricular wall thickness (IWT; median 1.7 cm), and reduced voltage-to-mass ratio (median 0.06 mm/[g/m2]). One hundred and thirteen patients (46%) had either light chain (n = 53) or transthyretin (n = 60) amyloidosis by cardiac biopsy. A prediction model including age, relative wall thickness, left atrial pressure by E/e', and low limb lead voltage (<0.5 mV) showed good discrimination for cardiac amyloidosis with an optimism-corrected c-index of 0.87 (95% CI 0.83-0.92). The diagnostic accuracy of this model (79% sensitivity, 84% specificity) surpassed that of traditional screening parameters, such as IWT in the absence of left ventricular hypertrophy on ECG (98% sensitivity, 20% specificity) and IWT with low limb lead voltage (49% sensitivity, 91% specificity). CONCLUSION: Among patients with an advanced infiltrative cardiomyopathy phenotype, traditional biomarker, ECG, and echocardiography-based screening tests have limited individual diagnostic utility for cardiac amyloidosis. A prediction algorithm including age, relative wall thickness, E/e', and low limb lead voltage improves the detection of cardiac biopsy-proven disease.

Left atrial strain imaging differentiates cardiac amyloidosis and hypertensive heart disease.

Echocardiographic diagnosis of cardiac amyloidosis (CA) can be difficult to differentiate from increased left ventricular (LV) wall thickness from hypertensive heart disease. The aim of this study was to evaluate left atrial (LA) function and deformation using strain and strain rate (SR) imaging in cardiac amyloidosis. We reviewed 44 cases of CA confirmed by tissue biopsy or a combination of clinical and cardiac imaging data. Cases were classified according two subgroups: amyloid light chain (AL) or amyloid transthyretin (ATTR). These subjects underwent 2D-Speckle tracking echocardiographic derived (STE) LA strain analysis. These were compared to 25 hypertensive (HT) patients with increased LV wall thickness. The three phases of LA function were evaluated using strain and strain rate parameters. Despite a similar increase in LV wall thickness, all LA strain parameters were significantly reduced in the AL cohort compared to the HT cohort (reservoir strain/LAs: 11.0 vs. 24.8%, p < 0.05). The ATTR cohort had significantly thicker LV walls and higher atrial fibrillation burden compared to AL and HT patients but similar reduction in LA strain values compared to AL group. A reservoir strain (S-LAs) cut off value of 20% was 86.4% sensitive and 88.6% specific for detecting CA compared to HT heart disease in this cohort. LA strain parameters were able to identify LA dysfunction in all types of CA. LA function in CA is significantly worse compared with hypertensive patients despite similar increase in LV wall thickness. In combination with other clinical and imaging features, LA strain may provide incremental value in differentiating cardiac amyloidosis from increased wall thickness secondary to hypertension.

Transthyretin cardiac amyloidosis: A treatable form of heart failure with a preserved ejection fraction.

Cardiac amyloidosis (CA) is considered a rare disease with poor prognosis and limited therapeutic options. However, non-biopsy diagnostic modalities as well as emerging therapies are challenging this long-held belief. Radionuclide bone scintigraphy is increasingly being used in the diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CA). As such, it is expected that the number of patients diagnosed with ATTR-CA will continue to rise. Emerging therapies decrease the progressive morbidity and mortality associated with ATTR-CA. The importance of early recognition of ATTR-CA is imperative as prompt initiation of these novel agents is essential to maximize their therapeutic potential. Herein, we outline the current approach to diagnosis of ATTR-CA and review the therapeutic management of the disease.

Poor right ventricular function is associated with impaired exercise capacity and ventilatory efficiency in transthyretin cardiac amyloid patients.

CardioPulmonary Exercise Test (CPET) is the gold standard to evaluate functional capacity in patients at high risk of heart failure (HF). Few studies with a limited number of subjects and conflicting results, analyzed the role of CPET in patients with systemic amyloidosis. Aims of our study were the assessment of the response to exercise in patients with Transthyretin amyloid (ATTR) cardiomyopathy (CA), and the correlation of clinical, biohumoral and echocardiographic parameters with CPET parameters, such as VO2 peak and VE/VCO2 slope. From February 2018 to March 2019, 72 cardiac ATTR patients were prospectively enrolled and underwent a complete clinical, biohumoral, echocardiographic and CPET assessment. All patients completed the exercise stress test protocol, without any adverse event. At CPET, they achieved a mean VO2 peak of 14 mL/Kg/min and a mean VE/VCO2 slope of 31. The blood pressure response to exercise was inadequate in 26 (36%) patients (flat in 25 and hypotensive in 1), while 49/72 patients (69%) showed an inadequate heart rate recovery. In multivariate analysis, s' tricuspidalic was the only independent predictor of VO2 peak, while in the two test models performed to avoid collinearity, both TAPSE and s' tricuspidalic were the strongest independent predictors of VE/VCO2 slope. Our data demonstrate the role of right ventricular function as an independent predictor of exercise capacity and ventilatory efficiency in ATTR. In CPET evaluation, a significant proportion of patients presented an abnormal arterial pressure response and heart rate variation to exercise.

Deep learning to diagnose cardiac amyloidosis from cardiovascular magnetic resonance.

BACKGROUND: Cardiovascular magnetic resonance (CMR) is part of the diagnostic work-up for cardiac amyloidosis (CA). Deep learning (DL) is an application of artificial intelligence that may allow to automatically analyze CMR findings and establish the likelihood of CA. METHODS: 1.5 T CMR was performed in 206 subjects with suspected CA (n = 100, 49% with unexplained left ventricular (LV) hypertrophy; n = 106, 51% with blood dyscrasia and suspected light-chain amyloidosis). Patients were randomly assigned to the training (n = 134, 65%), validation (n = 30, 15%), and testing subgroups (n = 42, 20%). Short axis, 2-chamber, 4-chamber late gadolinium enhancement (LGE) images were evaluated by 3 networks (DL algorithms). The tags "amyloidosis present" or "absent" were attributed when the average probability of CA from the 3 networks was ≥ 50% or < 50%, respectively. The DL strategy was compared to a machine learning (ML) algorithm considering all manually extracted features (LV volumes, mass and function, LGE pattern, early blood-pool darkening, pericardial and pleural effusion, etc.), to reproduce exam reading by an experienced operator. RESULTS: The DL strategy displayed good diagnostic accuracy (88%), with an area under the curve (AUC) of 0.982. The precision (positive predictive value), recall score (sensitivity), and F1 score (a measure of test accuracy) were 83%, 95%, and 89% respectively. A ML algorithm considering all CMR features had a similar diagnostic yield to DL strategy (AUC 0.952 vs. 0.982; p = 0.39). CONCLUSIONS: A DL approach evaluating LGE acquisitions displayed a similar diagnostic performance for CA to a ML-based approach, which simulates CMR reading by experienced operators.