Left atrial size is an independent predictor of overall survival in patients with primary systemic amyloidosis

Left Atrial Strain Imaging by Speckle Tracking Echocardiography: The Supportive Diagnostic Value in Cardiac Amyloidosis and Hypertrophic Cardiomyopathy

Background: Left atrial (LA) function is crucial for assessing left ventricular filling in various cardiovascular conditions. Cardiac Amyloidosis (CA) is characterized by atrial myopathy and LA function impairment, with diastolic dysfunction up to restrictive filling pattern, leading to progressive heart failure and arrhythmias. This study evaluates LA function and deformation using speckle tracking echocardiography (STE) in patients with CA compared to a cohort of patients with sarcomeric Hypertrophic Cardiomyopathy (HCM) and a control group. Methods: We conducted a retrospective, observational study (from January 2019 to December 2022) including a total of 100 patients: 33 with ATTR-CA, 34 with HCMs, and 33 controls. Clinical evaluation, electrocardiograms, and transthoracic echocardiography were performed. Echocardiogram images were analyzed in post-processing using EchoPac software for LA strain quantification, including LA-reservoir, LA-conduit, and LA-contraction strain. Results: The CA group exhibited significantly impaired LA function compared to HCMs and control groups, with LA-reservoir median values of -9%, LA-conduit -6.7%, and LA-contraction -3%; this impairment was consistent even in the CA subgroup with preserved ejection fraction. LA strain parameters correlated with LV mass index, LA volume index, E/e', and LV-global longitudinal strain and were found to be associated with atrial fibrillation and exertional dyspnea. Conclusions: LA function assessed by STE is significantly impaired in CA patients compared to HCMs patients and healthy controls. These findings highlight the potential supportive role of STE in the early detection and management of the disease.

A novel echocardiographic risk score for light-chain amyloidosis

Aims

The prognosis of light-chain (AL) amyloidosis, a plasma cell dyscrasia, is largely determined by the presence of cardiac involvement. Conventional staging is achieved using cardiac biomarkers (high-sensitivity troponin, N-terminal pro-beta natriuretic peptide) and free light-chain difference (Mayo staging). We sought to evaluate the role of echocardiographic parameters as prognostic markers in AL amyloidosis and examine their utility compared with conventional staging.

Methods and results

Seventy-five consecutive patients with AL amyloidosis reviewed at a referral amyloid clinic who underwent comprehensive echocardiographic assessment were retrospectively identified. The evaluated echocardiographic parameters included left ventricular (LV) ejection fraction, mass, diastolic function parameters, global longitudinal strain (GLS), and left atrial (LA) volume. Mortality was assessed through a review of clinical records. During a median follow-up of 51 months, 29/75 (39%) patients died. Patients who died had a larger LA volume (47 ± 12 vs. 35 ± 10 mL/m², P < 0.001) and a higher E/e' (18 ± 10 vs. 14 ± 6, P = 0.026). Univariate clinical and echocardiographic predictors of survival included LA volume, E/e', e', LVGLS, and Mayo stage (at significance of P < 0.1). Left atrial volume and LVGLS were significant determinants of mortality when examined using clinical cut-offs, although E/e' was not. A composite echocardiographic risk score comprising LA volume and LVGLS provided similar prognostic performance to Mayo stage [area under the curve (AUC) 0.75, 95% confidence interval (CI) 0.64-0.85 vs. AUC 0.75, 95% CI 0.65-0.858, P = 0.91].

Conclusion

Left atrial volume and LVGLS were independent predictors of mortality in AL amyloidosis. A composite echocardiographic score combining LA volume and LVGLS has similar prognostic power to Mayo stage for all-cause mortality.

A Review of Current and Evolving Imaging Techniques in Cardiac Amyloidosis

Purpose of review

Establishing an early, efficient diagnosis for cardiac amyloid (CA) is critical to avoiding adverse outcomes. We review current imaging tools that can aid early diagnosis, offer prognostic information, and possibly track treatment response in CA.

Recent findings

There are several current conventional imaging modalities that aid in the diagnosis of CA including electrocardiography, echocardiography, bone scintigraphy, cardiac computed tomography (CT), and cardiac magnetic resonance (CMR) imaging. Advanced imaging techniques including left atrial and right ventricular strain, and CMR T1 and T2 mapping as well as ECV quantification may provide alternative non-invasive means for diagnosis, more granular prognostication, and the ability to track treatment response.

Summary

Leveraging a multimodal imaging toolbox is integral to the early diagnosis of CA; however, it is important to understand the unique role and limitations posed by each modality. Ongoing studies are needed to help identify imaging markers that will lead to an enhanced ability to diagnose, subtype and manage this condition.

Left atrial remodeling and the prognostic value of feature tracking derived left atrial strain in patients with light-chain amyloidosis: a cardiovascular magnetic resonance study

Systemic light-chain (AL) amyloidosis is characterized by the aggregation of misfolded immunoglobulin light chain, predominantly infiltrating in the heart, including left atrium (LA). LA remodeling, such as increased interatrial septal thickness and enlarged size, has been observed. However, LA strain assessed by cardiac magnetic resonance feature tracking (CMR-FT) and its prognostic role remains to be further determined. Using CMR, the current study sought to investigate the characteristic of LA remodeling and the prognostic value of LA strain in patients with AL. Eighty-seven consecutive patients who underwent CMR with histologically confirmed systemic light-chain amyloidosis were retrospectively enrolled. LA strain parameters were analyzed based on CMR-FT algorithm. Amyloid infiltration and burden loads were assessed with CMR late gadolinium enhancement (LGE) and extracellular volume (ECV). Patients were categorized according to the extent of amyloid infiltration in cardiac myocardium. The primary endpoint was defined as all-cause mortality. The prognosis value of LA strain indices was evaluated using Cox proportional hazards regression and Kaplan-Meier curves. Interatrial septal thickness (3 [2-5] vs. 4 [3-5] mm, p = 0.007) and indexed LA volume (34.6 [26.9-44.6] vs. 50.5 [36.1-58.5] ml/m2, p = 0.001) were significantly higher in patients with atrial involvement (LA-LGE). Compared with patients with low amyloid burden loads (ECV group I), those at moderate and high (ECV group II and III) show progressive impairment in LA reservoir, conduit, and booster strains and strain rates. A total of 44 patients died during a median follow-up of 12 months. In multivariate analysis, LA reservoir strain, New York Heart Association (NYHA), and ECV remained independently associated with survival. On Kaplan-Meier analyses, low LA reservoir strain (< 8.6%) increased the risk of mortality. In moderate amyloid burden loads patients, low LA reservoir strain provides additive prognosis value. Progress left atrial remodeling and dysfunction are common findings in AL cardiac amyloidosis. The CMR-FT-derived LA reservoir strain provides independent and additive prognostic value for all-cause mortality in patients with AL cardiac amyloidosis.

Magnetic-Resonance-Imaging-Based Left Atrial Strain and Left Atrial Strain Rate as Diagnostic Parameters in Cardiac Amyloidosis

Aims: The present study aims to evaluate magnetic-resonance-imaging (MRI)-assessed left atrial strain (LAS) and left atrial strain rate (LASR) as potential parameters for the diagnosis of cardiac amyloidosis (CA), the distinction of clinical subtypes and differentiation from other cardiomyopathies. Methods and results: LAS and LASR were assessed by MRI feature tracking in patients with biopsy-proven CA. LAS and LASR of patients with CA were compared to healthy subjects and patients with hypertrophic cardiomyopathy. LAS and LASR were also analyzed concerning differences between patients with transthyretin (ATTR) and light chain amyloidosis (AL). A total of 44 patients with biopsy-proven CA, 19 patients with hypertrophic cardiomyopathy and 24 healthy subjects were included. In 22 CA patients (50%), histological examination identified ATTR as CA subtype and AL in the remaining patients. No significant difference was observed for reservoir, conduit or booster LAS in patients with AL or ATTR. Reservoir LAS, conduit LAS and booster LAS were significantly reduced in patients with CA and HCM as compared to healthy subjects (p < 0.001). Reservoir LAS and booster LAS were significantly reduced in CA as compared to HCM patients (p < 0.001). A linear correlation was observed between LA global reservoir strain and LA-EF (p < 0.001, r = 0.5), conduit strain and global longitudinal LV strain (p < 0.001, r = 0.5), global booster strain rate and LA-EF (p < 0.001, r = 0.6) and between global booster strain rate and LA area at LVED (p < 0.0001, 0.5). Conclusions: LAS and LASR are severely impaired in patients with CA. The MRI-based assessment of LAS and LASR might allow non-invasive diagnosis and categorization of CA and its distinct differentiation from other hypertrophic phenotypes.

Prognostic value of left atrial mechanics in cardiac light-chain amyloidosis with preserved ejection fraction: a cohort study

Background

Light-chain amyloidosis is a plasma cell disorder associated with poor outcomes, especially when the heart is involved. The characteristics of left atrial (LA) function and its prognostic implications in cardiac amyloidosis (CA) have not been fully investigated.

Methods

Between April 2014 and June 2019, 93 patients with a diagnosis of CA, normal left ventricular ejection fraction (LVEF) and sinus rhythm were included. Their clinical, baseline echocardiographic and follow-up data were investigated. LA function, including LA strain and strain rate, was assessed using 2D speckle tracking echocardiography in different LA functional phases.

Results

Among all patients, 38 (40.9%) died. Multivariate Cox regression analyses showed that LA mechanics regarding LA reservoir and booster pump functions were independent predictors for overall survival. Traditional echocardiographic parameters for LA structure like LA volume index and LA width were not associated with mortality. Moreover, LA strain and strain rate in reservoir and contractile phases improved the discrimination and goodness of fit of the conventional prognostic model, the Mayo criteria 2004 and 2012, in our study population. Decreased LA mechanics were associated with impaired left ventricular (LV) systolic and diastolic function, and LA reservoir and contractile functions were associated with LA structure.

Conclusions

Assessment of LA reservoir and contractile functions via 2D speckle tracking echocardiographic LA mechanical indices provide clinical and prognostic insights into cardiac light-chain amyloidosis patients, especially those with preserved EF and sinus rhythm. Emphasizing the monitoring of LA function may be beneficial for the prognosis prediction of CA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02589-7.

Transthyretin Cardiac Amyloidosis and Novel Therapies to Treat This Not-so-rare Cause of Cardiomyopathy

Transthyretin cardiac amyloidosis (ATTR-CA) is typically a late-onset disease caused by the deposit of transthyretin amyloid fibrils throughout the heart. When this occurs, various cardiac sequelae can develop, including hypotension, conduction abnormalities, and valvular lesions. The cardiomyopathy caused by ATTR-CA (ATTR-CM) has proven difficult to treat. Until recently, symptomatic management was the only therapeutic option, and many therapies used to treat congestive heart failure were ineffective or even detrimental to patients with ATTR-CM. In addition, treatment was limited to heart and liver transplantation. As a result, prognosis was poor. Recently, a few drug therapies have come to light as potential treatment modalities for ATTR-CM, most notably tafamidis, sold under the brand names Vyndaqel and Vyndamax. After the phase III Transthyretin Amyloidosis Cardiomyopathy trial displayed the drug's efficacy, it was given breakthrough therapy designation and was approved by the Food and Drug Administration on May 6, 2019, for the treatment of ATTR-CA. This novel therapy, as well as various other therapies in the pipeline, such as inotersen and patisiran, provide hope where, until recently, there was little. Unfortunately, the exorbitant cost of these new therapies may present a barrier to long-term treatment for some patients. However, by further improving diagnostic algorithms and incorporating these new treatments into our existing therapeutic modalities, patients with ATTR-CA should be able to live far longer than previously expected. Finally, further research combining these novel treatment modalities must be done, as they may prove to be additive or even synergistic in their treatment of ATTR amyloidosis.

Echocardiographic assessment of cardiac amyloidosis

Cardiac amyloidosis, a form of infiltrative cardiomyopathy, is associated with poor prognosis in untreated patients. Early diagnosis is important for timely initiation of effective therapies. Despite advances in diagnostic modalities, it remains a challenging diagnosis, requiring high index of clinical suspicion. Echocardiography represents the first-line cardiac imaging modality for evaluation of heart failure and suspected cardiac amyloidosis. In this review, we discuss echocardiographic findings in cardiac amyloidosis.

Multimodality Imaging in Cardiac Amyloidosis

PURPOSE OF REVIEW

Cardiac amyloidosis is an increasingly recognized condition with a growing range of targeted therapies, but diagnosis requires a high index of suspicion and multimodality imaging expertise. Early diagnosis remains key to improving quality of life and survival. This article reviews the multimodality imaging approach to the diagnosis, differentiation, and prognosis of cardiac amyloidosis.

RECENT FINDINGS

Recent advances in multimodality cardiac imaging have allowed for earlier diagnosis of cardiac amyloidosis resulting in earlier initiation of life-saving therapy in cases of light chain amyloidosis and life-prolonging therapy in transthyretin amyloidosis. With these advances in multimodality imaging, it is important for cardiologists and cardiac imagers to be aware of the subtleties of early disease, the appropriate diagnostic approach as well as understanding the practicalities and pitfalls that are encountered with each modality.

Phasic left atrial strain analysis to discriminate cardiac amyloidosis in patients with unclear thick heart pathology

AIMS

Traditional echocardiographic parameters for the assessment of suspected cardiac amyloidosis (CA) are of limited diagnostic accuracy. We sought to explore differences and the discriminative value of phasic left atrial strain (LAS) reductions and of regional longitudinal left ventricular (LV) strain alterations (relative apical sparing; RELAPS) in CA and other causes of LV wall thickening (LVH).

METHODS AND RESULTS

We included 54 patients with unclear LVH (mean septal diastolic wall thickness 17.8 ± 3.5 mm); CA was bioptically confirmed in 35 patients (8 mATTR, 6 wtATTR, 20 AL, and 1 AA amyloidosis) and LVH in 19 subjects. We analysed RELAPS as well as LA reservoir (LASr), conduit (LAScd), and contraction strain (LASct) using 2D speckle tracking echocardiography (EchoPAC software, GE). RELAPS was higher (1.37 ± 0.94 vs. 0.86 ± 0.29, P < 0.007), whereas atrial mechanics were significantly reduced in CA (LASr, LAScd, and LASct: 9.7 ± 5.2%, -6.5 ± 3.5%, and -5.0 ± 4.1% in CA; and 22.7 ± 7.8%, -13.9 ± 5.2%, and -13.0 ± 5.5% in LVH, respectively; P < 0.001 each). With an area under the curve (AUC) of 0.91 [95% confidence interval (CI) 0.82-0.99], LASr showed a higher diagnostic accuracy in discriminating CA than RELAPS (AUC 0.74, 95% CI 0.59-0.88). LASr and LAScd remained significantly associated with CA in a multivariate regression model.

CONCLUSION

Phasic LAS was significantly reduced in patients with CA and showed a higher diagnostic accuracy in discriminating CA than RELAPS. The additional assessment of phasic LAS may be useful to rule in the possible diagnosis of CA in patients with unclear LVH.

Multimodality imaging in cardiac amyloidosis: a primer for cardiologists

Amyloidosis is a systemic infiltrative disease, in which unstable proteins misfold, form aggregates and amyloid fibrils which can deposit in various organs: heart, kidneys, liver, gastrointestinal tract, nervous system structures, lungs, or soft tissue. Cardiac amyloidosis (CA) diagnosis requires awareness, high level of clinical suspicion and expertise in integrating clinical, electrocardiographic, and multimodality imaging data. The overall scenario is complex and no single test emerges over the others, but different techniques are useful at various stages of the diagnostic workup. After a clinical suspicion of CA is raised by various non-imaging red-flags, eligible patients should undergo complete echocardiography and multiparametric cardiovascular magnetic resonance imaging. Even though the clinical suspicion of CA is confirmed by cardiac imaging, the accurate differentiation between the two most frequent and treatable amyloid types, i.e. light chain (AL) and transthyretin (ATTR) requires further work-up including phosphate scintigraphy. This article reviews the latest and essential data on multimodality imaging of patients with suspected or confirmed CA in a useful and practical manner for the general and imaging cardiologists.

Contemporary narrative review on left atrial strain mechanics in echocardiography: cardiomyopathy, valvular heart disease and beyond

Left atrial (LA) strain mechanics refer to the measurement of LA myocardial deformation expressed as a percentage, and have been gathering interest over the last decade with expanding research supporting their utility in multiple cardiovascular disorders. Measured through advanced dynamic imaging techniques which include tissue Doppler imaging (TDI) and two-dimensional (2D) speckle tracking echocardiography (STE), LA strain mechanics are affected by left ventricular diastolic dysfunction prior to the onset of functional and structural changes in the left ventricle (LV). There is a need for practising cardiologists to become more familiar with the clinical utility of LA strain mechanics. In this article, we begin by reviewing the physiologic function of the LA, using this as a basis for understanding LA strain mechanics. The focus of this review article is to provide a contemporary update on the utility of LA strain mechanics in a range of cardiovascular disorders, including atrial fibrillation (AF), hypertrophic cardiomyopathy (HCM), valvular pathologies, coronary artery disease (CAD) as well as systemic diseases, such as hypertension (HTN), obesity and diabetes mellitus (DM). This article also highlights the current limitations in more widespread clinical applications of LA strain mechanics, as well as outlining the future perspectives on the clinical applications of LA strain mechanics.

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.

Multi-modality imaging of cardiac amyloidosis: Contemporary update

Cardiac amyloidosis is a heterogeneous and challenging diagnostic disease with poor prognosis that is now being altered by introduction of new therapies. Echocardiography remains the first-line imaging tool, and when disease is suspected on echocardiography, cardiac magnetic resonance imaging and nuclear imaging play critical roles in the non-invasive diagnosis and evaluation of cardiac amyloidosis. Advances in multi-modality cardiac imaging allowing earlier diagnosis and initiation of novel therapies have significantly improved the outcomes in these patients. Cardiac imaging also plays important roles in the risk stratification of patients presenting with cardiac amyloidosis. In the current review, we provide a clinical and imaging focused update, and importantly outline the imaging protocols, diagnostic and prognostic utility of multimodality cardiac imaging in the assessment of cardiac amyloidosis.

Prevalence of cardiovascular risk factors and diseases in patients with multiple myeloma undergoing autologous peripheral blood stem cell transplantation

Multiple myeloma (MM) is the second most common hematologic malignancy and occurs similar to cardiovascular diseases (CVD), in the sixth/seventh decade. The aim of this retrospective cohort study was to evaluate the prevalence and prognostic value of cardiovascular risk factors (CVRF) and CVD in 325 patients with MM undergoing autologous peripheral blood stem cell transplantation (PBSCT) at the University Hospital of Würzburg between 03/2004 and 12/2011. Mean age in the total cohort was 61 years. Among CVRF, prevalence of arterial hypertension was highest (59.7%), followed by overweight (54.2%) and positive smoking history (18.2%). The prevalence of heart failure (3.1%) or coronary heart disease (4.8%) was low. During a median follow-up of 36 months, 18% of the patients died. Hypertension (HR = 1.83, p = 0.048) as well as positive smoking history (HR = 2.13, p = 0.02) were independently associated with increased mortality risk in multivariate analysis. In a subgroup analysis of 100 patients echocardiographic parameters were compared before and after PBSCT. Echocardiography revealed a significant reduction of left atrial diameters (–1.5 mm, p = 0.009) and septum thickness (–1.0 mm, p = 0.001), non-significant reduction of systolic function, and an increase of the prevalence of diastolic dysfunction (+14%; p = 0.01). In this study CVRF, especially hypertension and smoking, are strong predictors of poor survival in patients with MM undergoing autologous PBSCT. Echocardiography before and after treatment shows subtle changes in systolic function but an increase of the prevalence of diastolic dysfunction.

[Not Available]

In this article we present brief overview of the subject of amyloidosis and involvement of the cardiovascular system, the criteria for diagnosis, principles of treatment, and the clinical case of cardiac amyloidosis.

Left atrial structure and function in cardiac amyloidosis

Aims

Although cardiac amyloidosis (CA) is characterized by significant left atrial (LA) dilatation, the characteristics of LA function remain to be fully investigated.

Methods and results

We assessed LA function by speckle-tracking echocardiography in 124 patients with CA and sinus rhythm: 68 with light chain (AL), 29 with mutant (ATTRm), 27 with wild-type (ATTRwt) transthyretin amyloidosis. Conventional and strain-derived parameters, including LA peak longitudinal strain (LS) and strain rate (peak LSR: reservoir function; early LSR: conduit function; late LSR: active function), were assessed compared between CA patients and 20 healthy controls of similar age and gender. All LA function phases, including LA longitudinal strain, peak LSR, early and late LSR were significantly impaired in CA compared to healthy controls after adjusting for LA size, LV ejection fraction and LV filling pressures (E/E') (all P < 0.05). Peak LA LS was moderately correlated with LV global LS (R = -0.60, P < 0.001); late LSR was correlated with A wave at the level of LV inflow (R = -0.69, P < 0.001). Among the different CA subtypes, peak LS and LA active emptying fraction were worse in ATTRwt than AL and ATTRm [P < 0.05 after adjustment for age, sex, body mass index, systolic blood pressure, heart rate, LA volume index, severity of mitral regurgitation, left ejection fraction, and left ventricular end-diastolic pressure (E/E')].

Conclusion

In CA, LA function was severely impaired and highly correlated with LV deformation. Differences in LA function between amyloid subtypes suggest that amyloid aetiology plays a role in the pathophysiology of cardiac dysfunction in CA.

Cardiac Structural and Functional Consequences of Amyloid Deposition by Cardiac Magnetic Resonance and Echocardiography and Their Prognostic Roles

OBJECTIVES

This cross-sectional study aimed to describe the functional and structural cardiac abnormalities that occur across a spectrum of cardiac amyloidosis burden and to identify the strongest cardiac functional and structural prognostic predictors in amyloidosis using cardiac magnetic resonance (CMR) and echocardiography.

BACKGROUND

Cardiac involvement in light chain and transthyretin amyloidosis is the main driver of prognosis and influences treatment strategies. Numerous measures of cardiac structure and function are assessed by multiple imaging modalities in amyloidosis.

METHODS

A total f 322 subjects (311 systemic amyloidosis and 11 transthyretin gene mutation carriers) underwent comprehensive CMR and transthoracic echocardiography. The probabilities of 11 commonly measured structural and functional cardiac parameters being abnormal with increasing cardiac amyloidosis burden were evaluated. Cardiac amyloidosis burden was quantified using CMR-derived extracellular volume. The prognostic capacities of these parameters to predict death in amyloidosis were assessed using Cox proportional hazards models.

RESULTS

Left ventricular mass and mitral annular plane systolic excursion by CMR along with strain and E/e' by echocardiography have high probabilities of being abnormal at low cardiac amyloid burden. Reductions in biventricular ejection fractions and elevations in biatrial areas occur at high burdens of infiltration. The probabilities of indexed stroke volume, myocardial contraction fraction, and tricuspid annular plane systolic excursion (TAPSE) being abnormal occur more gradually with increasing extracellular volume. Ninety patients (28%) died during a median follow-up of 22 months (interquartile range: 10 to 38 months). Univariable analysis showed that all imaging markers studied significantly predicted outcome. Multivariable analysis showed that TAPSE (hazard ratio: 1.46; 95% confidence interval: 1.16 to 1.85; p < 0.01) and indexed stroke volume (hazard ratio: 1.24; 95% confidence interval: 1.04 to 1.48; p < 0.05) by CMR were the only independent predictors of mortality.

CONCLUSIONS

Specific functional and structural abnormalities characterize different burdens of cardiac amyloid deposition. In a multimodality imaging assessment of a large cohort of amyloidosis patients, CMR-derived TAPSE and indexed stroke volume are the strongest prognostic cardiac functional markers.

Left atrial dysfunction in light-chain cardiac amyloidosis and hypertrophic cardiomyopathy - A comparative three-dimensional speckle-tracking echocardiographic analysis from the MAGYAR-Path Study

INTRODUCTION

While cardiac amyloidosis (CA) is a rare systemic disease characterized by extracellular deposition of protein-derived fibrils, hypertrophic cardiomyopathy (HCM) is histopathologically characterized by myocyte hypertrophy and disarray, interstitial fibrosis, and small intramural coronary arteriole dysplasia. The aim of the present study was to compare left atrial (LA) volumetric and functional characteristics between light-chain (AL) CA and HCM by three-dimensional (3D) speckle-tracking echocardiography (STE).

METHODS

The AL-CA group initially consisted of 17 patients with AL-CA, but one patient was excluded due to inadequate image quality, and so the study population consisted of 16 patients (mean age: 64.0±9.6 years, five men). Their results were compared with data on 20 age-matched HCM patients (mean age: 59.8±5.2 years, 10 men) and on 16 age-matched healthy controls (mean age: 58.2±7.2 years, six men). Complete two-dimensional Doppler echocardiography and 3D-STE were performed in all cases.

RESULTS

Significantly increased LA volumes were observed in both AL-CA and HCM compared with the control group. Only active atrial emptying fraction was found to be significantly reduced in AL-CA patients compared to controls. Peak global and mean segmental circumferential, longitudinal and area strains showed significant reductions in AL-CA patients compared with controls, but only peak mean segmental longitudinal strain differed significantly between HCM patients and controls. While no differences were demonstrated in global and mean segmental strain at atrial contraction between HCM patients and controls, AL-CA patients showed reductions in certain strain parameters compared to controls and HCM patients.

CONCLUSIONS

Different patterns of LA functional characteristics were demonstrated in AL-CA and HCM patients by 3D-STE.

Left atrial function in patients with light chain amyloidosis: A transthoracic 3D speckle tracking imaging study

BACKGROUND

Systemic light chain amyloidosis (AL) is characterized by the extracellular deposition of amyloid fibrils. Transthoracic echocardiography is the modality of choice to assess cardiac function in patients with AL. Whereas left ventricular (LV) function has been well studied in this patient population, data regarding the value of left atrial (LA) function in AL patients are lacking. In this study, we aim to examine the impact of LA volumes and function on survival in AL patients as assessed by real-time 3D echocardiography.

METHODS

A total of 77 patients (67±10 years, 60% men) with confirmed AL and 39 healthy controls were included. All standard 2D echocardiographic and 3D-LA parameters were obtained.

RESULTS

Fourteen patients (18%) were in Mayo Clinic (MC) stage I, 30 (39%) in stage II, and 33 (43%) in stage III at initial evaluation. There was no significant difference among the MC stages groups in terms of age, gender, or cardiovascular risk factors. As compared to patients in MC II and MC I, those in MC III had significantly larger indexed 3D-LA volumes (MCIII: 46±15mL/m², MC II: 38±12mL/m², and MC I: 23±9mL/m², p<0.0001), lower 3D-LA total emptying fraction (3D-tLAEF) (21±13% vs. 31±15% vs. 43±7%, respectively, p<0.0001), and worse 3D peak atrial longitudinal strain (3D-PALS) (11±9% vs. 18±13% vs. 20±7%, respectively, p=0.007). Two-year survival was significantly lower in patients with 3D-tLAEF <+34% (p=0.003) and in those with 3D-PALS <+14% (p=0.034). Both parameters provided incremental prognostic value over maximal LA volume in multivariate analysis.

CONCLUSION

Functional LA parameters are progressively altered in AL patients according to the MC stage. A decrease in 3D-PALS is associated with worse outcome, independently of LA volume.

Echocardiographic Predictors for Worsening of Six-Minute Walk Distances in Patients With Systemic Sclerosis (Scleroderma)

Change in 6-minute walk distance (6MWD) has been used as a clinical marker in pulmonary hypertension. Determinants and worsening of 6MWD remain a matter of debate because nonpulmonary factors have an impact on the 6MWD. We hypothesized that future reduction of 6MWD in patients with systemic sclerosis (SSc) was more closely associated with cardiac dysfunction. We prospectively performed standard clinical and echocardiographic evaluations in SSc patients with the 6-minute walk test at enrollment. Features associated with the 6MWD were sought in a multiple linear regression analysis and compared using standardized β. Worsening of the 6MWD was defined as a 15% reduction and served as the primary outcome. Eighty-one patients were included. In the multivariate analysis, baseline 6MWD was related to SSc severity score (β = -0.250, p = 0.024), left atrial volume index (β = -0.222, p = 0.046), right ventricular fractional area change (β = 0.252, p = 0.025), and the ratio of mean pulmonary artery pressure and cardiac output (β = -0.31, p = 0.002). During follow-up, 20 patients reached the primary outcome. In sequential Cox models, a model based on right ventricular fractional area change at baseline (chi-square 4.8) was improved by left atrial volume index (chi-square 10.3, p = 0.007). In conclusion, determinants and worsening of 6MWD are explained by cardiac factors. When using the 6MWD as a clinical marker in pulmonary hypertension patients, their left ventricular diastolic function and right ventricular systolic function should be taken into consideration.

Characterization of Cardiac Amyloidosis by Atrial Late Gadolinium Enhancement Using Contrast-Enhanced Cardiac Magnetic Resonance Imaging and Correlation With Left Atrial Conduit and Contractile Function

The diagnosis of cardiac amyloidosis (CA) often necessitates invasive myocardial biopsy. We sought to evaluate whether late gadolinium enhancement (LGE) of the atrial myocardium by cardiac magnetic resonance imaging was associated with impaired left atrial (LA) function and whether the extent of LA LGE may enhance diagnostic differentiation of CA from other cardiomyopathies. Twenty-two patients with biopsy-proven CA, 37 with systemic hypertension (SH), and 22 with nonischemic dilated cardiomyopathy (NIDC) underwent cardiac magnetic resonance imaging and echocardiographic evaluation. Patients with CA had greater minimal LA volume (57 ± 53 vs 24 ± 18 in SH and 19 ± 25% in NIDC, p = 0.003), and significantly lower total LA emptying function (19 ± 14 vs 40 ± 14 in SH and 33 ± 20% in NIDC, p = 0.0006). The mean proportion of atrial enhancement (LGELA%) was significantly greater in patients with CA than with SH and NIDC (59 ± 36% vs 7.4 ± 2.1 and 2.9 ± 9.0%, p <0.0001, respectively). There was also a strong inverse correlation between both active and total atrial emptying (r = -0.69, p = 0.001; r = -0.67, p = 0.01, respectively) with LGELA% for patients with CA. In multivariate regression analysis, LGELA% was the strongest adjusted predictor for CA diagnosis. Using receiver operating characteristic analysis, LGELA% ≥33% produced the greatest diagnostic utility for CA (sensitivity 76%, specificity 94%). Patients with CA may have extensive LGE of the LA myocardium, which is associated with marked reduction in LA emptying function. The extent of LA LGE was highly predictive for the diagnosis of CA.

Pericardial Effusion and Multiple Organ Involvement Are Independent Predictors of Mortality in Patients with Systemic Light Chain Amyloidosis

OBJECTIVE

Left ventricular (LV) functions assessed by echocardiography and cardiac biomarkers are strong predictors of mortality in patients with systemic light chain (AL) amyloidosis. However, most previous studies have been conducted in Western countries, and the predictors of mortality in Asian patients with AL amyloidosis have not been characterized. To address this issue, we aimed to determine the predictors of mortality in Asian patients with biopsy-confirmed AL amyloidosis.

METHODS

We retrospectively enrolled 31 patients (59±11 years, 55% men) in whom AL amyloidosis was confirmed by biopsies from cardiac or non-cardiac tissues. Of these patients, 15 (48%) met the international echocardiographic criteria for cardiac amyloidosis (mean LV wall thickness >12 mm without other causes of LV hypertrophy).

RESULTS

During a mean follow-up period of 21±20 months, 15 patients died. Non-survivors had a higher number of involved organs, lower e', and higher rates of E/e' >15, pericardial effusion (PE), low voltage on an electrocardiogram and a New York Heart Association (NYHA) functional class ≥ III, compared with survivors. In multivariate analysis, a NYHA functional class ≥ III (p=0.024) and cardiac involvement (p=0.032) were independent predictors of PE in patients with AL amyloidosis. Multivariate Cox proportional hazard analysis indicated that PE (hazard ratio: 21.9, p=0.025) and the number of involved organs (hazard ratio: 2.8, p=0.015), but not LV diastolic parameters of tissue Doppler echocardiography, independently predict mortality in patients with AL amyloidosis.

CONCLUSION

PE and multiple organ involvement, compared with e' and E/e', are stronger predictors of mortality in patients with AL amyloidosis. The advanced disease stage of AL amyloidosis might underlie the strong association between PE and a poor outcome.

[AL amyloidosis]

AL amyloidosis belongs to the group of conformational diseases. It is the most common type of amyloidosis with an estimated 500 new cases per year in France. It is due to a small and usually indolent plasma cell clone which synthesizes an unstable, misfolded monoclonal immunoglobulin light chain that is prone to aggregate and form amyloid fibrils. Non-invasive biopsy such as abdominal fat aspiration or minor salivary gland biopsy should be performed to confirm the diagnosis and if negative, involved tissues have to be examined. Clinical presentation is very diverse, as AL amyloidosis can affect almost any organ or tissue in the body, other than the brain. The kidney is the most frequent organ involved, whereas heart disease characterized by restrictive cardiomyopathy is the most severe. Early diagnosis, before advanced cardiomyopathy, is essential for improving outcome. The association of alkylating agent and high-dose dexamethasone is effective in almost two-thirds of patients. Combinations of proteasome inhibitors, dexamethasone, and alkylating agents achieve high response rates. Close monitoring of clonal and organ response is mandatory to guide therapy changes and duration. New treatments designed to eliminate amyloid deposits are under development.

Osteopontin: a novel predictor of survival in patients with systemic light-chain amyloidosis

BACKGROUND

Troponin-T (cTnT) and NT-proBNP provide prognostic information in light-chain amyloidosis (AL). Thus, these biomarkers are widely used in clinical routine for risk stratification. Recently, plasma level of osteopontin (OPN), a secreted phosphoglycoprotein expressed by a variety of cell types, has been reported as a risk predictor in various cardiovascular diseases.

METHODS

OPN was determined retrospectively in 150 consecutive patients newly diagnosed with AL amyloidosis. All patients were evaluated according to a routine protocol including electrocardiography, echocardiography and laboratory testing.

RESULTS

Mean OPN was 591 ± 37 ng/mL. Cardiac involvement was established in 83 (55.3%). Median OPN plasma level were associated with number of organs involved, renal function, eligibility for high-dose melphalan chemotherapy and autologous stem cell transplantation, and severity of cardiac amyloidosis. Median follow-up was 19.2 months. 1-year all-cause-survival was 83.4%. The cut-offs discriminating 1-year all-cause-mortality for NT-proBNP, troponin T, and OPN were 2544 ng/L, 0.035 µg/L, and 426.8 ng/mL, respectively. Outcome was worse in patients with biomarkers above the individual ROC derived cut-off. A significant improvement of survival was observed in patients with cTNT >0.035 µg/L or NT-proBNP >2544 ng/L and OPN below ROC-derived cut-off of 426.8 ng/mL as compared to patients with OPN above 426.8 ng/L. No further discrimination was achieved by OPN in the cohorts of low troponin T or low NT-proBNP, respectively. Separate multivariate models identified OPN (cut-off 426.8 ng/mL) and troponin T (cut-off 0.035 µg/L) as independent predictors of all-cause-mortality.

CONCLUSIONS

These data demonstrated that OPN appears to be a valuable marker in the clinical routine for evaluation of patients with AL amyloidosis, especially if it is used in combination with cTNT and/or NT-proBNP.

Prognostic value of high-sensitivity cardiac troponin T in patients with endomyocardial-biopsy proven cardiac amyloidosis

OBJECTIVE

To investigate prognostic predictors of long-term survival of patients with cardiac amyloidosis (CA), and to determine predictive value of high-sensitivity cardiac troponin T (hs-cTnT) in CA patients.

METHODS

We recruited 102 consecutive CA cases and followed these patients for 5 years. We described their clinical characteristics at presentation and used a new, high-sensitivity assay to determine the concentration of cTnT in plasma samples from these patients.

RESULTS

The patients with poor prognosis showed older age (56 ± 12 years vs. 50 ± 15 years, P = 0.022), higher incidences of heart failure (36.92% vs. 16.22%, P = 0.041), pericardial effusion (60.00% vs. 35.14%, P = 0.023), greater thickness of interventricular septum (IVS) (15 ± 4 mm vs. 13 ± 4 mm, P = 0.034), higher level of hs-cTnT (0.186 ± 0.249 ng/mL vs. 0.044 ± 0.055 ng/mL, P = 0.001) and higher NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels (11,742 ± 10,464 pg/mL vs. 6,031 ± 7,458 pg/mL, P = 0.006). At multivariate Cox regression analysis, heart failure (HR: 1.78, 95%CI: 1.09-2.92, P = 0.021), greater wall thickness of IVS (HR: 1.44, 95%CI: 1.04-3.01, P = 0.0375) and higher hs-cTnT level (HR: 6.16, 95%CI: 2.20-17.24, P = 0.001) at enrollment emerged as independent predictors of all-cause mortality.

CONCLUSIONS

We showed that hs-cTnT is associated with a very ominous prognosis, and it is also the strongest predictor of all-cause mortality in multivariate analysis. Examination of hs-cTnT concentrations provides valuable prognostic information concerning long-term outcomes.

Role of imaging in the diagnosis and management of patients with cardiac amyloidosis: state of the art review and focus on emerging nuclear techniques

Amyloidosis is an infiltrative disease characterized by deposition of amyloid fibrils within the extracellular tissue of one or multiple organs. Involvement of the heart, cardiac amyloidosis, is recognized as a common cause of restrictive cardiomyopathy and heart failure. The two major types of cardiac amyloidosis are cardiac amyloid light-chain (AL) and transthyretin-related cardiac amyloidosis (ATTR, mutant and wild types) (Nat Rev Cardiol 2010;7:398-408). While early recognition of cardiac amyloidosis is of major clinical importance, so is the ability to differentiate between subtypes. Indeed, both prognosis and therapeutic options vary drastically depending on the subtype. While endomyocardial biopsy with immunostaining is considered the gold standard, advances in imaging provide an attractive non-invasive alternative. Currently, electrocardiography, echocardiography, and cardiac magnetic resonance imaging are all used in the evaluation of cardiac amyloidosis with varying diagnostic and prognostic accuracy. Yet, none of these modalities can effectively differentiate the cardiac amyloid subtypes. Recent data with (99m)Tc-phosphate derivatives, previously used as bone seeking radioactive tracers, have shown promising results; these radiotracers selectively bind ATTR, but not AL subtype, and can differentiate subtypes with high diagnostic accuracy. This review will initially present the non-radionuclide imaging techniques and then focus on the radionuclide imaging techniques, particularly (99m)Tc-DPD and (99m)Tc-PYP, mechanism of action, performance and interpretation of the study, diagnostic accuracy, prognostic value, future clinical perspective, and outlook.

Cardiac amyloidosis: updates in diagnosis and management

Amyloidosis is a severe systemic disease. Cardiac involvement may occur in the three main types of amyloidosis (acquired monoclonal light-chain, hereditary transthyretin and senile amyloidosis) and has a major impact on prognosis. Imaging the heart to characterize and detect early cardiac involvement is one of the major aims in the assessment of this disease. Electrocardiography and transthoracic echocardiography are important diagnostic and prognostic tools in patients with cardiac involvement. Cardiac magnetic resonance imaging better characterizes myocardial involvement, functional abnormalities and amyloid deposition due to its high spatial resolution. Nuclear imaging has a role in the diagnosis of transthyretin amyloid cardiomyopathy. Cardiac biomarkers are now used for risk stratification and staging of patients with light-chain systemic amyloidosis. Different types of cardiac complications may occur, including diastolic followed by systolic heart failure, atrial and/or ventricular arrhythmias, conduction disturbances, embolic events and sometimes sudden death. Senile amyloid and hereditary transthyretin amyloid cardiomyopathy have better prognoses than light-chain amyloidosis. Cardiac treatment of heart failure is usually ineffective and is often poorly tolerated because of its hypotensive and bradycardiac effects. The three main types of amyloid disease, despite their similar cardiac appearance, have specific new aetiological treatments that may change the prognosis of this disease. Cardiologists should be aware of this disease to allow early treatment.

Evaluation of patients with cardiac amyloidosis using echocardiography, ECG and right heart catheterization

AIMS

To characterize patients with cardiac amyloidosis using echocardiography, electrocardiogram (ECG) and right heart catheterization (RHC).

METHODS AND RESULTS

Fourteen patients with biopsy verified light chain or transthyretin cardiac amyloidosis were included. All patients had heart failure with markedly elevated NT-proBNP. Echocardiography demonstrated biventricular hypertrophy, left atrial enlargement and normal to slightly reduced left ventricular ejection fraction. Tissue Doppler septal é was low and median E/é was high. Within 6 months RHC was performed in eight of the patients. The restrictive filling pattern demonstrated by echocardiography corresponded well to median pulmonary wedge pressure (21 mmHg). Systolic pulmonary artery pressure (SPAP) was increased, whereas cardiac output and stroke volume were seen to be decreased with both methods. ECG demonstrated: low voltage (36%), abnormal R-progression (65%), ST-T abnormalities (71%) and high incidence of fibrillation (36%). In addition, a case report following the treatment of melphalan and dexamethasone is presented with improvement of hypertrophy, SPAP, left ventricular mass and é.

CONCLUSION

These findings should lead to a suspicion of cardiac amyloidosis and suggest further investigation.