暂无摘要。

BACKGROUND: The 6-minute walk test (6MWT) represents a comprehensive functional assessment that is commonly used in patients with heart failure; however, data are lacking in patients with transthyretin cardiac amyloidosis (ATTR-CA).
OBJECTIVE: This study aimed to assess the prognostic importance of the 6MWT in patients with ATTR-CA.
METHODS: A retrospective analysis of patients diagnosed with ATTR-CA at the National Amyloidosis Centre who underwent a baseline 6MWT between 2011 and 2023 identified 2,141 patients, of whom 1,118 had follow-up at 1 year.
RESULTS: The median baseline 6MWT distance was 347 m (Q1-Q3: 250-428 m) and analysis by quartiles demonstrated an increased death rate with each distance reduction (deaths per 100 person-years: 6.3 vs 9.2 vs 13.6 vs 19.0; log-rank P < 0.001). A 6MWT distance of <350 m was associated with a 2.2-fold higher risk of mortality (HR: 2.15; 95% CI: 1.85-2.50; P < 0.001), with a similar increased risk across National Amyloidosis Centre disease stages (P for interaction = 0.761) and genotypes (P for interaction = 0.172). An absolute (reduction of >35 m) and relative worsening (reduction of >5%) of 6MWT at 1 year was associated with an increased risk of mortality (HR: 1.80; 95% CI: 1.51-2.15; P < 0.001 and HR: 1.89; 95% CI: 1.59-2.24; P < 0.001, respectively), which was similar across the aforementioned subgroups. When combined with established measures of disease progression (N-terminal pro-B-type natriuretic peptide progression and outpatient diuretic intensification), each incremental increase in progression markers was associated with an increased death rate (deaths per 100 person-years: 7.6 vs 13.9 vs 22.4 vs 32.9; log-rank P < 0.001).
CONCLUSIONS: The baseline 6MWT distance can refine risk stratification beyond traditional prognosticators. A worsening 6MWT distance can stratify disease progression and, when combined with established markers, identifies patients at the highest risk of mortality.

暂无摘要。

BACKGROUND: Transthyretin cardiac amyloidosis (ATTR-CA) is a progressive cardiomyopathy. The clinical course varies among individuals and there are no established measures to assess disease progression.
OBJECTIVE: The goal of this study was to assess the prognostic importance of an increase in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and outpatient diuretic intensification (ODI) as markers of disease progression in a large cohort of patients with ATTR-CA.
METHODS: We evaluated landmark survival analysis based on worsening of NT-proBNP and requirement for ODI between time of diagnosis and a 1-year visit, and subsequent mortality in 2,275 patients with ATTR-CA from 7 specialist centers. The variables were developed in the National Amyloidosis Centre (NAC) cohort (n = 1,598) and validated in the external cohort from the remaining centers (n = 677).
RESULTS: Between baseline and 1-year visits, 551 (34.5%) NAC patients and 204 (30.1%) patients in the external validation cohort experienced NT-proBNP progression (NT-proBNP increase >700 ng/L and >30%), which was associated with mortality (NAC cohort: HR: 1.82; 95% CI: 1.57-2.10; P < 0.001; validation cohort: HR: 1.75; 95% CI: 1.32-2.33; P < 0.001). At 1 year, 451 (28.2%) NAC patients and 301 (44.5%) patients in the external validation cohort experienced ODI, which was associated with mortality (NAC cohort: HR: 1.88; 95% CI: 1.62-2.18; P < 0.001; validation cohort: HR: 2.05; 95% CI: 1.53-2.74; P < 0.001). When compared with patients with a stable NT-proBNP and stable diuretic dose, a higher risk of mortality was observed in those experiencing either NT-proBNP progression or ODI (NAC cohort: HR: 1.93; 95% CI: 1.65-2.27; P < 0.001; validation cohort: HR: 1.94; 95% CI: 1.36-2.77; P < 0.001), and those experiencing both NT-proBNP progression and ODI (NAC cohort: HR: 2.98; 95% CI: 2.42-3.67; P < 0.001; validation cohort: HR: 3.23; 95% CI: 2.17-4.79; P < 0.001).
CONCLUSIONS: NT-proBNP progression and ODI are frequent and consistently associated with an increased risk of mortality. Combining both variables produces a simple, universally applicable model that detects disease progression in ATTR-CA.

We identified two patients with transthyretin (ATTR) amyloid myopathy (one ATTR variant amyloidosis, ATTRv; one wild-type ATTR amyloidosis, ATTRwt). Myopathy was the initial manifestation in ATTRwt, whereas it followed neuropathy and cardiomyopathy in ATTRv. The ATTRwt patient showed muscular tracer uptake on 99mTc-DPD planar scintigraphy at the time of initial diagnosis, consistent with ATTR amyloid myopathy. The ATTRv patient underwent heart transplantation because of progressive heart failure. Within the next two years, progressive myopathic symptoms and extracardiac tracer uptake on 99mTc-DPD planar scintigraphy were documented, attributable to ATTR amyloid myopathy. Interstitial amyloid deposits were confirmed by muscle biopsy in both patients, with a particularly high amyloid burden in the adipose tissue. This case report highlights the frequent concomitant presence of cardiac ATTR amyloidosis and ATTR amyloid myopathy. ATTR amyloid myopathy may precede cardiac manifestation in ATTRwt or occur after heart transplantation in ATTRv. Due to the high diagnostic accuracy of 99mTc-DPD scintigraphy for detecting ATTR amyloid myopathy and the emergence of novel therapeutics, it is important to increase the awareness of its presence.

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

We identified two patients with transthyretin (ATTR) amyloid myopathy (one ATTR variant amyloidosis, ATTRv; one wild-type ATTR amyloidosis, ATTRwt). Myopathy was the initial manifestation in ATTRwt, whereas it followed neuropathy and cardiomyopathy in ATTRv. The ATTRwt patient showed muscular tracer uptake on 99mTc-DPD planar scintigraphy at the time of initial diagnosis, consistent with ATTR amyloid myopathy. The ATTRv patient underwent heart transplantation because of progressive heart failure. Within the next two years, progressive myopathic symptoms and extracardiac tracer uptake on 99mTc-DPD planar scintigraphy were documented, attributable to ATTR amyloid myopathy. Interstitial amyloid deposits were confirmed by muscle biopsy in both patients, with a particularly high amyloid burden in the adipose tissue. This case report highlights the frequent concomitant presence of cardiac ATTR amyloidosis and ATTR amyloid myopathy. ATTR amyloid myopathy may precede cardiac manifestation in ATTRwt or occur after heart transplantation in ATTRv. Due to the high diagnostic accuracy of 99mTc-DPD scintigraphy for detecting ATTR amyloid myopathy and the emergence of novel therapeutics, it is important to increase the awareness of its presence.

In [99mTc]Tc-DPD scintigraphy for myocardial ATTR amyloidosis, planar images 3 hour p.i. and SPECT/CT acquisition in L-mode are recommended. This study investigated if earlier planar images (1 hour p.i.) are beneficial and if SPECT/CT acquisition should be preferred in H-mode (180° detector angle) or L-mode (90°).
In SPECT/CT phantom measurements (NaI cameras, N = 2; CZT, N = 1), peak contrast recovery (CRpeak) was derived from sphere inserts or myocardial insert (cardiac phantom; signal-to-background ratio [SBR], 10:1 or 5:1). In 25 positive and 38 negative patients (reference: endomyocardial biopsy or clinical diagnosis), Perugini scores and heart-to-contralateral (H/CL) count ratios were derived from planar images 1 hour and 3 hour p.i.
In phantom measurements, accuracy of myocardial CRpeak at SBR 10:1 (H-mode, 0.95-0.99) and reproducibility at 5:1 (H-mode, 1.02-1.14) was comparable for H-mode and L-mode. However, L-mode showed higher variability of background counts and sphere CRpeak throughout the field of view than H-mode. In patients, sensitivity/specificity were ≥ 95% for H/CL ratios at both time points and visual scoring 3 hour. At 1 hour, visual scores showed specificity of 89% and reduced reader\'s confidence.
Early DPD images provided no additional value for visual scoring or H/CL ratios. In SPECT/CT, H-mode is preferred over L-mode, especially if quantification is applied apart from the myocardium.
ANTECEDENTES: En la gammagrafía con [ 99mTc]-DPD para amiloidosis cardiaca ATTR, se recomienda la adquisición de imágenes planares a las 3h p.i y SPECT/CT en modo L. Este estudio investigó si las imágenes planares más tempranas (1h p.i.) tienen beneficios y si la adquisición del SPECT/CT debería preferirse en modo H (ángulo de detección de 180 °) o en modo L (90 °). MéTODOS: En las mediciones con el fantoma del SPECT/CT (cámaras de NaI, n= 2; CZT, n=1), la recuperación pico de contraste (CRpico) se derivó de inserciones de esfera o de inserciones miocárdicas (fantoma cardiaco; relación señal-fondo [SBR], 10:1 o 5: 1). En 25 pacientes positivos y 38 negativos (referencia: biopsia endomiocárdica o diagnóstico clínico), el score de Perugini y la relación de cuentas corazón-contralateral (H/CL) se derivaron de imágenes planares a 1h y 3h p.i.
En mediciones con el fantoma, la precisión del CRpico miocárdico en SBR 10:1 (modo H, 0.95-0.99) y la reproducibilidad a 5:1 (modo H, 1.02-1.14) fue comparable para el modo H y el modo L. Sin embargo, el modo L mostró una mayor variabilidad de las cuentas de fondo y del CRpico de la esfera en todo el campo de visión que el modo H. En pacientes, la sensibilidad/especificidad fue ≥ 95% para las relaciones H/CL en ambos puntos de tiempo y con un score visual a las 3 h. A 1h, los scores visuales mostraron una especificidad de (89%) y disminución de la confianza del lector.
Las imágenes tempranas de DPD no proporcionaron ningún valor adicional para el score visual o las relaciones H/CL. En SPECT/CT, se prefiere el modo H sobre el modo L, especialmente si la cuantificación se aplica aparte del miocardio.
摘要: 背景: [99mTc]Tc-DPD闪烁显像检查心肌ATTR淀粉样变性时, 建议使用3h p.i.平面图像和L模式SPECT/CT扫描。本研究探讨了早期平面图像(1h p.i.)是否有益, 以及SPECT/CT采集是否应首选H模式(探测器角度180°)或L模式(90°)。 方法: 在SPECT/CT模体测量中(NaI相机, n=2;CZT, n=1), 峰值造影剂恢复(CRpeak)来自球体插入物或心肌插入物(心脏模体; 信号与背景比[SBR], 10:1 或5:1)。在25个阳性和38个阴性病人中(参考标准: 心内膜活检或临床诊断), Perugini分数和心脏/对侧 (H / CL)计数比率来自平面图像1 h和3 h p.i.。 结果: 在模体测量中, 心肌CRpeak的SBR准确性 10:1 (H-mode, 0.95 - 0.99)和可重复性5:1 (H-mode, 1.02 - 1.14), H模式和L 模式相当。然而, 与H模式相比, L模式在整个视野中表现出更高的背景计数和球形CRpeak变异性。在患者中, 两个时间点的H/CL比值以及3h视觉评分的敏感性/特异性均≥95%。1h时, 视觉评分特异性为89%, 阅读者的信心降低。 结论: DPD早期图像对视觉评分和H/CL比值没有额外的价值。在SPECT/CT中, H模式优于L模式, 特别是心肌之外定量时。.

Cardiac transthyretin-related (ATTR) amyloidosis is a severe cardiomyopathy for which therapeutic approaches are currently under development. Because non-invasive imaging techniques such as cardiac magnetic resonance imaging and echocardiography are non-specific, the diagnosis of ATTR amyloidosis is still based on myocardial biopsy. Thus, diagnosis of ATTR amyloidosis is difficult in patients refusing myocardial biopsy. Furthermore, myocardial biopsy does not allow 3D-mapping and quantification of myocardial ATTR amyloid. In this report we describe a 99mTc-DPD-based molecular imaging technique for non-invasive single-step diagnosis, three-dimensional mapping and semiquantification of cardiac ATTR amyloidosis in a patient with suspected amyloid heart disease who initially rejected myocardial biopsy. This report underlines the clinical value of SPECT-based nuclear medicine imaging to enable non-invasive diagnosis of cardiac ATTR amyloidosis, particularly in patients rejecting biopsy.