Role of Right Ventricular Strain Measured by Two-Dimensional Echocardiography in the Diagnosis of Cardiac Amyloidosis

Imaging modalities in cardiac amyloidosis

Cardiac amyloidosis (CA) is an infiltrative restrictive cardiomyopathy caused by the deposition of amyloid fibrils in the myocardium, presenting primarily as transthyretin cardiac amyloidosis (ATTR) and immunoglobulin light chain cardiac amyloidosis (AL). ATTR is further classified into wild-type (ATTRwt) and hereditary (ATTRv) based on transthyretin gene mutation. The disease is increasingly recognized as a significant cause of heart failure. Advances in diagnostic modalities, including electrocardiography, echocardiography, cardiac magnetic resonance imaging, and technetium pyrophosphate scintigraphy, have revolutionized the non-invasive diagnosis of CA. While ATTR can often be diagnosed with scintigraphy, AL typically requires histological confirmation. This review explores these diagnostic tools, emphasizing their role in early detection and quantification of disease burden, which are crucial for timely treatment and prognostication. This comprehensive overview aims to aid clinicians in efficiently diagnosing CA, ultimately improving patient outcomes.

Right Ventricular Strain Improves the Echocardiographic Diagnosis and Risk Stratification of Transthyretin Cardiac Amyloidosis Among Other Phenotypes of Left Ventricular Hypertrophy

AIMS

Cardiac amyloidosis is a diffuse disease affecting all cardiac chambers. The value of right ventricular free-wall strain is uncertain as an echocardiographic red flag. We hypothesized that right ventricular free-wall strain is of added value for diagnostic and prognostic purposes in patients with transthyretin cardiac amyloidosis (ATTR-CA).

METHOD

A diagnosis of ATTR-CA required positive Tc-99m pyrophosphate scintigraphy and negative serum clonal dyscrasia. Patients with left ventricular (LV) hypertrophy (LVH; interventricular septal thickness ≥1.2 cm) by echocardiography and negative pyrophosphate scintigraphy served as controls after exclusion of amyloid light-chain cardiac amyloidosis. Longitudinal strain was computed with speckle-tracking echocardiography.

RESULTS

We studied 108 subjects with ATTR-CA and 106 controls with LVH, retrospectively. Right ventricular free-wall strain was independently associated with the diagnosis of ATTR-CA after adjusting for classical echocardiographic parameters, namely, relative apical sparing (RAS), e', and E/e'. Right ventricular free-wall strain ≥ -16% was incremental to LV RAS in the overall group and in the subgroup without extreme wall thickness (≤1.4 cm; Harrell's C, net reclassification improvement = 0.213, P < .001; and net reclassification improvement = 0.463, P = .015, respectively). Major adverse cardiovascular and cerebrovascular events (heart failure hospitalization, stroke, death) occurred in 47 ATTR-CA patients, during follow-up (median, 38; range, 6-60 months). Right ventricular free-wall strain ≥-16% was associated with 3-fold increased risk of MACCE in ATTR-CA patients independently of age, comorbidities, B-type natriuretic peptide, and tafamidis treatment. Right ventricular free-wall strain was additive to LV ejection fraction for risk stratification (chi square = 10.2; P = .017).

CONCLUSIONS

Right ventricular free-wall strain >-16% has incremental value to LV RAS for the differential diagnosis of ATTR-CA among LVH phenotypes and is associated with poor prognosis.

Cardiac involvement in Anderson-Fabry disease. The role of advanced echocardiography

Anderson-Fabry disease (AFD) is a lysosomal storage disorder, depending on defects in alpha galactosidase A activity, due to a mutation in the galactosidase alpha gene. Cardiovascular involvement represents the leading cause of death in AFD. Cardiac imaging plays a key role in the evaluation and management of AFD patients. Echocardiography is the first-line imaging modality for the identification of the typical features of AFD cardiomyopathy. Advanced echocardiography that allows assessment of myocardial deformation has provided insights into the cardiac functional status of AFD patients. The present review highlights the value and the perspectives of advanced ultrasound imaging in AFD.

Diagnostic Modalities in the Detection of Cardiac Amyloidosis

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

Current trends and latest developments in echocardiographic assessment of right ventricular function: load dependency perspective

Right ventricle (RV) failure is a common complication of many cardiopulmonary diseases. Since it has a significant adverse impact on prognosis, precise determination of RV function is crucial to guide clinical management. However, accurate assessment of RV function remains challenging owing to the difficulties in acquiring its intricate pathophysiology and imaging its complex anatomical structure. In addition, there is historical attention focused exclusively on the left ventricle assessment, which has led to overshadowing and delayed development of RV evaluation. Echocardiography is the first-line and non-invasive bedside clinical tool for assessing RV function. Tricuspid annular plane systolic excursion (TAPSE), RV systolic tissue Doppler velocity of the tricuspid annulus (RV S'), and RV fractional area change (RV FAC) are conventional standard indices routinely used for RV function assessment, but accuracy has been subject to several limitations, such as load-dependency, angle-dependency, and localized regional assessment. Particularly, load dependency is a vexing issue, as the failing RV is always in a complex loading condition, which alters the values of echocardiographic parameters and confuses clinicians. Recently, novel echocardiographic methods for improved RV assessment have been developed. Specifically, "strain", "RV-pulmonary arterial (PA) coupling", and "RV myocardial work" are newly applied methods for RV function assessment, a few of which are designed to surmount the load dependency by taking into account the afterload on RV. In this narrative review, we summarize the latest data on these novel RV echocardiographic parameters and highlight their strengths and limitations. Since load independency is one of the primary advantages of these, we particularly emphasize this aspect.

Right heart and left atrial strain to differentiate cardiac amyloidosis and Fabry disease

Echocardiographic differentiation of cardiac amyloidosis (CA) and Fabry disease (FD) is often challenging using standard echocardiographic parameters. We retrospectively analyzed the diagnostic accuracy of right heart and left atrial strain parameters to discriminate CA from FD using receiver operating characteristic curve analyses and logistic regression models. A total of 47 FD and 88 CA patients with left ventricular wall thickening were analyzed. The comparison of both cardiomyopathies revealed significantly reduced global and free wall longitudinal right ventricular strain (RVS; global RVS: CA - 13 ± 4%, n = 67, vs. FD - 18 ± 4%, n = 39, p < 0.001) as well as right atrial strain (RAS; reservoir RAS: CA 12 ± 8%, n = 70, vs. FD 26 ± 9%, n = 40, p < 0.001) and left atrial strain (LAS) in CA patients. Individually, global RVS as well as phasic LAS and RAS showed the highest diagnostic accuracy to distinguish CA and FD. The best diagnostic accuracy was achieved by combining the age, basal RV diameter, global RVS, and reservoir and conduit RAS (area under the curve 0.96 [95% CI 0.90-1.00]). Differential echocardiographic diagnostic work-up of patients with suspected CA or FD can be improved by integrating structural and functional parameters of the right heart and the left atrium.Trial registration: DRKS00027403.

Advance of echocardiography in cardiac amyloidosis

Cardiac amyloidosis (CA) occurs when the insoluble fibrils formed by misfolded precursor proteins deposit in cardiac tissues. The early clinical manifestations of CA are not evident, but it is easy to progress to refractory heart failure with an inferior prognosis. Echocardiography is the most commonly adopted non-invasive modality of imaging to visualize cardiac structures and functions, and the preferred modality in the evaluation of patients with cardiac symptoms and suspected CA, which plays a vital role in the diagnosis, prognosis, and long-term management of CA. The present review summarizes the echocardiographic manifestations of CA, new echocardiographic techniques, and the application of multi-parametric echocardiographic models in CA diagnosis.

Association between the TAPSE to PASP ratio and short-term outcome in patients with light-chain cardiac amyloidosis

BACKGROUND

Amyloid light-chain cardiac amyloidosis (AL-CA) patients experiencing RV failure have a poorer prognosis. The echocardiographic ratio of tricuspid annular plane systolic excursion (TAPSE) to pulmonary arterial systolic pressure (PASP) serves as a non-invasive proxy for evaluating the coupling between the right ventricle (RV) and pulmonary circulation. The aim of this study was to assess the association between the TAPSE/PASP ratio and short-term outcome in patients with AL-CA.

METHODS

Seventy-one patients diagnosed with AL-CA were enrolled in this retrospective cohort study.Short-term outcome was defined as 6-month all-cause mortality. Receiver operating characteristic (ROC), logistic regression, and Kaplan-Meier analysis were used in this study.

RESULTS

Among seventy-one patients with AL-CA (mean age, 62 ± 8 years, 69% male), 17 (24%) died within the first 6 months (mean follow-up period 55 ± 48 days). Linear regression analysis indicated that the TAPSE/PASP ratio was correlated with RV global longitudinal strain (r = -0.655, p < 0.001), RV free wall thickness (r = -0.599, p < 0.001), and left atrial reservoir strain (r = 0.770, p < 0.001). The time-dependent ROC and the area under the curve (AUC) showed that the TAPSE/PASP ratio was a better predictor (AUC = 0.798; 95% confidence interval (CI): 0.677-0.929) of short-term outcome than TAPSE (AUC = 0.734; 95% CI: 0.585-0.882) and PASP (AUC: 0.730; 95% CI: 0.587-0.874). Multivariate logistic regression showed that patients with the worse TAPSE/PASP (< 0.47 mm/mmHg) and lower systolic blood pressure (< 100 mmHg) had the highest risk of dying.

CONCLUSIONS

The TAPSE/PASP ratio is associated with the short-term outcome of patients with AL-CA. The combination of TAPSE/PASP ratio < 0.474 mmHg and SBP < 100 mmHg could identify the subgroup of patients with AL-CA at elevated risk of poor prognosis.

Diagnosis and management of patients with left ventricular hypertrophy: Role of multimodality cardiac imaging. A scientific statement of the Heart Failure Association of the European Society of Cardiology

Left ventricular (LV) hypertrophy consists in an increased LV wall thickness. LV hypertrophy can be either secondary, in response to pressure or volume overload, or primary, i.e. not explained solely by abnormal loading conditions. Primary LV hypertrophy may be due to gene mutations or to the deposition or storage of abnormal substances in the extracellular spaces or within the cardiomyocytes (more appropriately defined as pseudohypertrophy). LV hypertrophy is often a precursor to subsequent development of heart failure. Cardiovascular imaging plays a key role in the assessment of LV hypertrophy. Echocardiography, the first-line imaging technique, allows a comprehensive assessment of LV systolic and diastolic function. Cardiovascular magnetic resonance provides added value as it measures accurately LV and right ventricular volumes and mass and characterizes myocardial tissue properties, which may provide important clues to the final diagnosis. Additionally, scintigraphy with bone tracers is included in the diagnostic algorithm of cardiac amyloidosis. Once the diagnosis is established, imaging findings may help predict future disease evolution and inform therapy and follow-up. This consensus document by the Heart Failure Association of the European Society of Cardiology provides an overview of the role of different cardiac imaging techniques for the differential diagnosis and management of patients with LV hypertrophy.

Imaging findings of right cardiac amyloidosis: impact on prognosis and clinical course

Cardiac involvement from amyloidosis is of growing interest in the overall literature. Despite cardiac amyloidosis (CA) has been considered for a long time a rare disease, the diagnostic awareness is increasing mainly thanks to the improvement of diagnostic softwares and of imaging techniques such as cardiac magnetic resonance  (CMR). Some authors have observed an increase of prevalence rate of CA; moreover it's often underestimated because clinical manifestations are aspecific. The interstitial infiltration of the left ventricle has been extensively studied, while the involvement of the right ventricle (RV) has been less investigated. Involvement of the RV, even in the absence of pulmonary hypertension or clearly left ventricle infiltration, plays an important role as prognostic factor and is useful to achieve an early diagnosis. Therefore, the use of fast and low-cost diagnostic methods such as ultrasound strain of the right ventricle could be used to recognize cardiac amyloidosis early. Herein the importance of evaluating the right ventricular involvement, which can predict the most severe course of the disease also without overt clinical manifestations. The role of imaging, in particular of echocardiography, CMR, and scintigraphy is here reported.

Imaging cardiac hypertrophy in hypertrophic cardiomyopathy and its differential diagnosis

PURPOSE OF REVIEW

The aim of this study was to review imaging of myocardial hypertrophy in hypertrophic cardiomyopathy (HCM) and its phenocopies. The introduction of cardiac myosin inhibitors in HCM has emphasized the need for careful evaluation of the underlying cause of myocardial hypertrophy.

RECENT FINDINGS

Advances in imaging of myocardial hypertrophy have focused on improving precision, diagnosis, and predicting prognosis. From improved assessment of myocardial mass and function, to assessing myocardial fibrosis without the use of gadolinium, imaging continues to be the primary tool in understanding myocardial hypertrophy and its downstream effects. Advances in differentiating athlete's heart from HCM are noted, and the increasing rate of diagnosis in cardiac amyloidosis using noninvasive approaches is especially highlighted due to the implications on treatment approach. Finally, recent data on Fabry disease are shared as well as differentiating other phenocopies from HCM.

SUMMARY

Imaging hypertrophy in HCM and ruling out other phenocopies is central to the care of patients with HCM. This space will continue to rapidly evolve, as disease-modifying therapies are under investigation and being advanced to the clinic.

Assessment and diagnosis of right ventricular failure-retrospection and future directions

The right ventricle (RV) has a critical role in hemodynamics and right ventricular failure (RVF) often leads to poor clinical outcome. Despite the clinical importance of RVF, its definition and recognition currently rely on patients' symptoms and signs, rather than on objective parameters from quantifying RV dimensions and function. A key challenge is the geometrical complexity of the RV, which often makes it difficult to assess RV function accurately. There are several assessment modalities currently utilized in the clinical settings. Each diagnostic investigation has both advantages and limitations according to its characteristics. The purpose of this review is to reflect on the current diagnostic tools, consider the potential technological advancements and propose how to improve the assessment of right ventricular failure. Advanced technique such as automatic evaluation with artificial intelligence and 3-dimensional assessment for the complex RV structure has a potential to improve RV assessment by increasing accuracy and reproducibility of the measurements. Further, noninvasive assessments for RV-pulmonary artery coupling and right and left ventricular interaction are also warranted to overcome the load-related limitations for the accurate evaluation of RV contractile function. Future studies to cross-validate the advanced technologies in various populations are required.

Association of Left Atrial Hemodynamics by Magnetic Resonance Imaging With Long-Term Outcomes in Patients With Cardiac Amyloidosis

BACKGROUND

Left atrial (LA) function and strain patterns by magnetic resonance imaging (MRI) have been investigated as markers of several cardiovascular pathologies, including cardiac amyloidosis (CA). However, associations with clinical outcomes have not been investigated.

PURPOSE

To compare LA function and strain by MRI in CA patients to a matched cohort of patients without cardiovascular disease (CVD) and evaluate the association with long-term clinical outcomes in CA patients.

STUDY TYPE

Retrospective case control.

POPULATION

A total of 51 patients with CA and 51 age-, gender-, and race-matched controls without CVD who underwent MRI in sinus rhythm.

FIELD STRENGTH/SEQUENCE

ECG-gated balanced steady-state free precession sequence at 1.5 T.

ASSESSMENT

All measurements were completed by one investigator (M.M.B.). LA function and strain parameters were measured including LA indexed minimum and maximum volumes, LA reservoir (R), contractile (CT), and conduit (CD) strain. We compared groups after adjusting for age, hypertension, New York Heart Association class, modified staging system (troponin-I, BNP, estimated GFR) and left ventricular ejection fraction (LVEF) for an endpoint of all-cause mortality and a composite endpoint of heart failure hospitalization (HFH) or death.

STATISTICAL TESTS

Differences between groups were evaluated with t tests for continuous variables or χ² tests for categorical variables. A multivariable regression model was used to assess the associations of the P values-two-sided tests-<0.05 were considered statistically significant.

RESULTS

CA patients with median follow up of 4.9 (8.5) months had significantly lower LA strain and higher LA volumes in comparison to the matched cohort. In the multivariable analysis, only LVEF was significantly associated with death while ƐCT (OR 0.6, CI: 0.41-0.89), indexed minimum LA volume (OR 1.06, CI: 1.02-1.13) and indexed maximum LA volume (OR 1.08, CI: 1.01-1.15) were significantly associated with the composite outcome of death or HFH.

CONCLUSION

In this retrospective study of CA patients, ƐCT and indexed minimum and maximum LA volumes were significantly associated with the composite outcome of death or HFH.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 3.

Left ventricular assist device in cardiac amyloidosis: friend or foe?

The prevalence of cardiac amyloidosis has progressively increased over the last years, being recognized as a significant cause of heart failure. In fact, the management of advanced heart failure is a cornerstone treatment of amyloid cardiomyopathy due to the frequent delay in its diagnosis. Left ventricular assist devices (LVADs) have been gaining importance in the scenario of end-stage heart failure, representing an alternative to heart transplant. However, only few studies have investigated the role of LVAD in restrictive cardiomyopathies such as cardiac amyloidosis, since there are several problems to consider. In fact, both anatomical factors and the restrictive physiology of this condition make LVAD implant a relevant challenge in this subset of patients. Furthermore, due to the systemic involvement of amyloidosis, several factors have to be considered after LVAD implant, such as an increased risk of bleeding and right ventricular failure. This review attempts to summarize the current evidence of LVAD in cardiac amyloidosis, especially focusing on the challenges that this cardiomyopathy imposes both to the implant and to its management thereafter.

Microcalcification and 99mTc-Pyrophosphate Uptake without Increased Bone Metabolism in Cardiac Tissue from Patients with Transthyretin Cardiac Amyloidosis

Transthyretin cardiac amyloidosis (ATTR-CA) is characterized by high ^99mTc-labeled bone tracer uptake in the heart. However, the mechanism of bone tracer uptake into the heart remains controversial. Since bone tracer uptake into metastatic bone tumors is thought to be associated with increased bone metabolism, we examined ^99mTc-pyrophosphate (PYP) scintigraphy findings, endomyocardial biopsy (EMB) tissue findings, and the expression of bone metabolism-related genes in the EMB tissues in patients with ATTR-CA, amyloid light-chain cardiac amyloidosis (AL-CA), and noncardiac amyloidosis (non-CA) in this study. The uptake of ^99mTc-PYP in the heart was significantly higher in the ATTR-CA patients than in the AL-CA and non-CA patients. A higher percentage of ATTR-CA EMB tissue showed von Kossa-positive microparticles: ATTR-CA, 62%; AL-CA, 33%; and non-CA, 0%. Calcified microparticles were identified using transmission electron microscopy. However, none of the osteogenic marker genes, osteoclastic marker genes, or phosphate/pyrophosphate-related genes were upregulated in the EMB samples from ATTR-CA patients compared to those from AL-CA and non-CA patients. These results suggest that active calcification-promoting mechanisms are not involved in the microcalcification observed in the heart in ATTR-CA. The mechanisms explaining bone tracer uptake in the heart, which is stronger than that in the ribs, require further investigation.

Right Ventricle Involvement by Glycogen Storage Cardiomyopathy (PRKAG2): Standard and Advanced Echocardiography Analyses

BACKGROUND

PRKAG2 syndrome is a rare, early-onset autosomal dominant inherited disease. We aimed to describe the right ventricle (RV) echocardiographic findings using two and three-dimensional (2D and 3D) modalities including myocardial deformation indices in this cardiomyopathy. We also aimed to demonstrate whether this technique could identify changes in RV function that could distinguish any particular findings.

METHODS

Thirty patients with genetically proven PRKAG2 (R302Q and H401Q), 16 (53.3%) males, mean age 39.1 ± 15.4 years, underwent complete echocardiography examination. RV-focused, 4-chamber view was acquired for 2D and 3D measurements. Student's t or Wilcoxon-Mann-Whitney tests were used to compare numerical variables between 2 groups, and p < 0.05 was considered significant.

RESULTS

Twelve patients (40%) had a pacemaker implanted for 12.4 ± 9.9 years. RV free wall mean diastolic thickness was 7.9 ± 2.9 mm. RV 4-chamber longitudinal strain (RV4LS), including the free wall and interventricular septum, was -17.3% ± 6.7%, and RV free wall longitudinal strain (RVFWLS) was -19.1% ± 8.5%. The RVFWLS apical ratio measured 0.63 ± 0.15. Mean RV 3D ejection fraction (EF) was 42.6% ± 10.9% and below normal limits in 56.7% of patients. Positive correlation occurred between RV 3DEF, RV4LS, and RVFWLS, especially for patients without a pacemaker (p = 0.006).

CONCLUSION

RV involvement in PRKAG2 syndrome is frequent, occurring in different degrees. Echocardiography is a valuable tool in detecting RV myocardial abnormalities in this condition. The use of 2D RV4LS, RVFWLS, and 3DEF offers reliable indicators of RV systolic dysfunction in this rare, challenging cardiomyopathy.

Beyond Sarcomeric Hypertrophic Cardiomyopathy: How to Diagnose and Manage Phenocopies

PURPOSE OF REVIEW

We describe the most common phenocopies of hypertrophic cardiomyopathy, their pathogenesis, and clinical presentation highlighting similarities and differences. We also suggest a step-by-step diagnostic work-up that can guide in differential diagnosis and management.

RECENT FINDINGS

In the last years, a wider application of genetic testing and the advances in cardiac imaging have significantly changed the diagnostic approach to HCM phenocopies. Different prognosis and management, with an increasing availability of disease-specific therapies, make differential diagnosis mandatory. The HCM phenotype can be the cardiac manifestation of different inherited and acquired disorders presenting different etiology, prognosis, and treatment. Differential diagnosis requires a cardiomyopathic mindset allowing to recognize red flags throughout the diagnostic work-up starting from clinical and family history and ending with advanced imaging and genetic testing. Different prognosis and management, with an increasing availability of disease-specific therapies make differential diagnosis mandatory.

Multimodality imaging in cardiac amyloidosis: State-of-the-art review

Amyloidosis is a systemic disease, characterized by deposition of amyloid fibrils in various organs, including the heart. For the diagnosis of cardiac amyloidosis (CA) it is required a high level of clinical suspicion and in the presence of clinical, laboratorial, and electrocardiographic red flags, a comprehensive multimodality imaging evaluation is warranted, including echocardiography, magnetic resonance, scintigraphy, and computed tomography, that will confirm diagnosis and define the CA subtype, which is of the utmost importance to plan a treatment strategy. We will review the use of multimodality imaging in the evaluation of CA, including the latest applications, and a practical flow-chart will sum-up this evidence.

Suspicion, screening, and diagnosis of wild-type transthyretin amyloid cardiomyopathy: a systematic literature review

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt CM) is a more common disease than previously thought. Awareness of ATTRwt CM and its diagnosis has been challenged by its unspecific and widely distributed clinical manifestations and traditionally invasive diagnostic tools. Recent advances in echocardiography and cardiac magnetic resonance (CMR), non-invasive diagnosis by bone scintigraphy, and the development of disease-modifying treatments have resulted in an increased interest, reflected in multiple publications especially during the last decade. To get an overview of the scientific knowledge and gaps related to patient entry, suspicion, diagnosis, and systematic screening of ATTRwt CM, we developed a framework to systematically map the available evidence of (i) when to suspect ATTRwt CM in a patient, (ii) how to diagnose the disease, and (iii) which at-risk populations to screen for ATTRwt CM. Articles published between 2010 and August 2021 containing part of or a full diagnostic pathway for ATTRwt CM were included. From these articles, data for patient entry, suspicion, diagnosis, and screening were extracted, as were key study design and results from the original studies referred to. A total of 50 articles met the inclusion criteria. Of these, five were position statements from academic societies, while one was a clinical guideline. Three articles discussed the importance of primary care providers in terms of patient entry, while the remaining articles had the cardiovascular setting as point of departure. The most frequently mentioned suspicion criteria were ventricular wall thickening (44/50), carpal tunnel syndrome (42/50), and late gadolinium enhancement on CMR (43/50). Diagnostic pathways varied slightly, but most included bone scintigraphy, exclusion of light-chain amyloidosis, and the possibility of doing a biopsy. Systematic screening was mentioned in 16 articles, 10 of which suggested specific at-risk populations for screening. The European Society of Cardiology recommends to screen patients with a wall thickness ≥12 mm and heart failure, aortic stenosis, or red flag symptoms, especially if they are >65 years. The underlying evidence was generally good for diagnosis, while significant gaps were identified for the relevance and mutual ranking of the different suspicion criteria and for systematic screening. Conclusively, patient entry was neglected in the reviewed literature. While multiple red flags were described, high-quality prospective studies designed to evaluate their suitability as suspicion criteria were lacking. An upcoming task lies in defining and evaluating at-risk populations for screening. All are steps needed to promote early detection and diagnosis of ATTRwt CM, a prerequisite for timely treatment.

Multimodality Imaging in the Evaluation and Prognostication of Cardiac Amyloidosis

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy resulting from deposition of misfolded immunoglobulin light chains (AL-CA) or transthyretin (ATTR-CA) proteins in the myocardium. Survival varies between the different subtypes of amyloidosis and degree of cardiac involvement, but accurate diagnosis is essential to ensure initiation of therapeutic interventions that may slow or potentially prevent morbidity and mortality in these patients. As there are now effective treatment options for CA, identifying underlying disease pathogenesis is crucial and can be guided by multimodality imaging techniques such as echocardiography, magnetic resonance imaging, and nuclear scanning modalities. However, as use of cardiac imaging is becoming more widespread, understanding optimal applications and potential shortcomings is increasingly important. Additionally, certain imaging modalities can provide prognostic information and may affect treatment planning. In patients whom imaging remains non-diagnostic, tissue biopsy, specifically endomyocardial biopsy, continues to play an essential role and can facilitate accurate and timely diagnosis such that appropriate treatment can be started. In this review, we examine the multimodality imaging approach to the diagnosis of CA with particular emphasis on the prognostic utility and limitations of each imaging modality. We also discuss how imaging can guide the decision to pursue tissue biopsy for timely diagnosis of CA.

The Auxiliary Role of Cardiac Magnetic Resonance Feature-Tracking Parameters in the Differentiation between Cardiac Amyloidosis and Constrictive Pericarditis

OBJECTIVES

Cardiac amyloidosis (CA) and constrictive pericarditis (CP) are described as the differential diagnoses of restrictive hemodynamic alterations of the heart. We aimed to explain cardiac magnetic resonance (CMR) imaging findings (especially feature tracking (FT)) of CA and CP cases and compare them with healthy controls. Moreover, we evaluated the role of biventricular FT parameters in differentiating CA from CP.

METHODS

Thirty-eight patients who underwent CMR between February 2016 and January 2018 with the ultimate diagnosis of CA (19 patients) or CP (19 patients) were enrolled. We included biopsy-proven light-chain amyloidosis patients. The data of 28 healthy controls were utilized for comparison. The patients were followed up for 8-23 months to register mortality and their surveillance. All CMR morphological and functional data, including FT parameters, were recorded and analyzed.

RESULTS

Of only 13/19 (68.4%) CA patients who had the follow-up data, 11/13 (84.6%) died. One of The CP patients (5.3%) expired during the follow-up. Significant between-group differences were noted concerning the biventricular ejection fraction as well as global longitudinal, circumferential, and radial strain values (Ps < 0.001). The left ventricular (LV) global longitudinal strain (GLS) ≤10% was detected in 13/19 (68.4%) of the CA and 1/19 (5.3%) of CP cases (P < 0.001). A significant difference between the mean value of the LVGLS and LV global circumferential strain (GCS) of the basal LV level compared to the mid and apical levels was observed (Ps < 0.001) in the CA patients. The differences between the mean LVGLS and the GCS measures of the mid and apical LV levels were not significant (P=1 and P=0.06, respectively).

CONCLUSIONS

In our study, CA and CP severely disrupted ventricular strains. Biventricular GLS was meaningfully lower in the CA subjects. Therefore, strain analysis, especially in the longitudinal direction, could be helpful to differentiate CA from CP.

Diagnosis of wild-type transthyretin amyloid cardiomyopathy in Japan: red-flag symptom clusters and diagnostic algorithm

Wild‐type transthyretin amyloid cardiomyopathy (ATTRwt‐CM) is caused by the deposition of wild‐type transthyretin (TTR) amyloid fibrils in the heart. The age at diagnosis of ATTRwt‐CM is reported to be approximately 70–80 years, and patients commonly present with non‐disease‐specific cardiac abnormalities, such as heart failure with preserved ejection fraction and diastolic dysfunction. The disease can be fatal if left untreated, with an approximate survival of 3–5 years from diagnosis. An oral TTR stabilizer, tafamidis, has enabled early intervention for the treatment of ATTRwt‐CM. However, awareness of ATTRwt‐CM remains low, and misdiagnosis and a delay in diagnosis are common. This review discusses the epidemiology, characteristics, treatment strategy, and red‐flag symptoms and signs of ATTRwt‐CM based on the published literature, as well as recent advances in diagnostic modalities that enable early and accurate diagnosis of the disease. We also discuss an algorithm for early and accurate diagnosis of ATTRwt‐CM in daily clinical practice. In our diagnostic algorithm, a suspected diagnosis of ATTRwt‐CM should be triggered by unexplained left ventricular hypertrophy (LVH), which is LVH that cannot be explained by an increased afterload due to hypertension or valvular disease. In addition, heart failure symptoms, laboratory test results (N‐terminal pro‐B‐type natriuretic peptide, high‐sensitivity troponin T, or high‐sensitivity troponin I), electrocardiogram and imaging (echocardiogram or cardiac magnetic resonance) data, age (≥60 years), and medical history suggestive of ATTRwt‐CM (e.g. carpal tunnel syndrome) should be examined. Detailed examinations using bone scintigraphy and monoclonal protein detection tests followed by tissue biopsy, amyloid typing, and TTR genetic testing are warranted for a definite diagnosis of ATTRwt‐CM.

The Prognostic Importance of Right Ventricular Longitudinal Strain in Patients with Cardiomyopathies, Connective Tissue Diseases, Coronary Artery Disease, and Congenital Heart Diseases

Right ventricular (RV) systolic function represents an important independent predictor of adverse outcomes in many cardiovascular (CV) diseases. However, conventional parameters of RV systolic function (tricuspid annular plane excursion (TAPSE), RV myocardial performance index (MPI), and fractional area change (FAC)) are not always able to detect subtle changes in RV function. New evidence indicates a significantly higher predictive value of RV longitudinal strain (LS) over conventional parameters. RVLS showed higher sensitivity and specificity in the detection of RV dysfunction in the absence of RV dilatation, apparent wall motion abnormalities, and reduced global RV systolic function. Additionally, RVLS represents a significant and independent predictor of adverse outcomes in patients with dilated cardiomyopathy (CMP), hypertrophic CMP, arrhythmogenic RV CMP, and amyloidosis, but also in patients with connective tissue diseases and patients with coronary artery disease. Due to its availability, echocardiography remains the main imaging tool for RVLS assessment, but cardiac magnetic resonance (CMR) also represents an important additional imaging tool in RVLG assessment. The findings from the large studies support the routine evaluation of RVLS in the majority of CV patients, but this has still not been adopted in daily clinical practice. This clinical review aims to summarize the significance and predictive value of RVLS in patients with different types of cardiomyopathies, tissue connective diseases, and coronary artery disease.

Pseudoexfoliation syndrome: Are the eyes the mirror of the heart?

INTRODUCTION

Pseudoexfoliation syndrome (PEX) is a disease characterized by the accumulation of fibrillary material in the extracellular matrix in the eye and many tissues. Myocardial involvement occurs as in other storage diseases. Speckle tracking echocardiography is a quantitative echocardiography modality that enables the detection of subclinical changes that cannot be detected by standard echocardiographic evaluation. In this study, we aimed to evaluate potential subclinical myocardial dysfunction in PEX patients by speckle tracking echocardiography.

METHODS AND RESULTS

The study group consisting of 29 cardiac asymptomatic pseudoexfoliation syndromes and 30 healthy volunteers were included in this case-control cross-sectional study. Detailed echocardiographic evaluations and strain analyses of all participants were performed. Concerning standard echocardiographic parameters, there was only a marginally significant difference between the two groups in the e' mean wave, and it was lower in the PEX group than the control group (0.07 ± 0.03, 0.10 ± 0.08, respectively, P = .06). However, in strain echocardiography, the global longitudinal strain (GLS) value was observed to be significantly lower in the PEX group than the control group (-17.02 ± 2.02, -19.29 ± 2.26, respectively P < .001). GLS was observed to be an independent predictor in the multivariable logistic regression model made to determine independent predictors of PEX syndrome (OR = 0.59, CI = 0.418-0.832, P = .003).

CONCLUSION

Subclinical myocardial involvement in PEX syndrome, in which standard echocardiographic techniques are blinded, can be detected by the strain echocardiography. PEX causes deterioration in the deformation parameters of the left ventricle. Systemic involvement should not be forgotten in patients with PEX and cardiac functions should be monitored.

Predictors of cardiac involvement and survival in patients with primary systemic light-chain amyloidosis: roles of the clinical, chemical, and 3-D speckle tracking echocardiography parameters

Background

Light-chain (AL) amyloidosis is the most common type of systemic amyloidosis with poor prognosis. Currently, the predictors of cardiac involvement and prognostic staging systems are primarily based on conventional echocardiography and serological biomarkers. We used three-dimensional speckle tracking echocardiography (STE-3D) measurements of strain, hypothesizing that it could detect cardiac involvement and aid in prediction of mortality.

Methods

We retrospectively analysed 74 consecutive patients with biopsy-proven AL amyloidosis. Among them, 42 showed possible cardiac involvement and 32 without cardiac involvement. LV global longitudinal strain (GLS), global radial strain, global circumferential strain and global area strain (GAS) measurements were obtained.

Results

The GLS and GAS were considered significant predictors of cardiac involvement. The cut-off values discriminating cardiac involvement were 16.10% for GLS, 32.95% for GAS. During the median follow-up of 12.5 months (interquartile range 4–25 months), 20 (27%) patients died. For the Cox proportional model survival analysis, heart rate, cardiac troponin T, NT-proBNP levels, E/e’, GLS, and GAS were univariate predictors of death. Multivariate Cox model showed that GLS ≤ 14.78% and cardiac troponin T ≥ 0.049 mg/l levels were independent predictors of survival.

Conclusions

STE-3D measurements of LV myocardial mechanics could detect cardiac involvement in patients with AL amyloidosis; GLS and cardiac biomarkers can provided prognostic information for mortality prediction.