Longitudinal myocardial function assessed by tissue velocity, strain, and strain rate tissue Doppler echocardiography in patients with AL (primary) cardiac amyloidosis

Addressing Common Questions Encountered in the Diagnosis and Management of Cardiac Amyloidosis

Advances in cardiac imaging have resulted in greater recognition of cardiac amyloidosis in everyday clinical practice, but the diagnosis continues to be made in patients with late-stage disease, suggesting that more needs to be done to improve awareness of its clinical manifestations and the potential of therapeutic intervention to improve prognosis. Light chain cardiac amyloidosis, in particular, if recognized early and treated with targeted plasma cell therapy, can be managed very effectively. For patients with transthyretin amyloidosis, there are numerous therapies that are currently in late-phase clinical trials. In this review, we address common questions encountered in clinical practice regarding etiology, clinical presentation, diagnosis, and management of cardiac amyloidosis, focusing on recent important developments in cardiac imaging and biochemical diagnosis. The aim is to show how a systematic approach to the evaluation of suspected cardiac amyloidosis can impact the prognosis of patients in the modern era.

Assessment of cardiac allograft systolic function by global longitudinal strain: From donor to recipient

BACKGROUND

Cardiac allografts are routinely evaluated by left ventricular ejection fraction (LVEF) before and after transplantation. However, myocardial deformation analyses with LV global longitudinal strain (GLS) are more sensitive for detecting impaired LV myocardial systolic performance compared with LVEF.

METHODS

We analyzed echocardiograms in 34 heart donor-recipient pairs transplanted at Duke University from 2000 to 2013. Assessments of allograft LV systolic function by LVEF and/or LV GLS were performed on echocardiograms obtained pre-explanation in donors and serially in corresponding recipients.

RESULTS

Donors had a median LVEF of 55% (25th, 75th percentile, 54% to 60%). Median donor LV GLS was -14.6% (-13.7 to -17.3%); LV GLS was abnormal (ie, >-16%) in 68% of donors. Post-transplantation, LV GLS was further impaired at 6 weeks (median -11.8%; -11.0 to -13.4%) and 3 months (median -11.4%; -10.3 to -13.9%) before recovering to pretransplant levels in follow-up. Median LVEF remained ≥50% throughout follow-up. We found no association between donor LV GLS and post-transplant outcomes, including all-cause hospitalization and mortality.

CONCLUSIONS

GLS demonstrates allograft LV systolic dysfunction in donors and recipients not detected by LVEF. The clinical implications of subclinical allograft dysfunction detected by LV GLS require further study.

Cardiac MR elastography for quantitative assessment of elevated myocardial stiffness in cardiac amyloidosis

Purpose

To evaluate if cardiac magnetic resonance elastography (MRE) can measure increased stiffness in patients with cardiac amyloidosis. Myocardial tissue stiffness plays an important role in cardiac function. A noninvasive quantitative imaging technique capable of measuring myocardial stiffness could aid in disease diagnosis, therapy monitoring, and disease prognostic strategies. We recently developed a high‐frequency cardiac MRE technique capable of making noninvasive stiffness measurements.

Materials and Methods

In all, 16 volunteers and 22 patients with cardiac amyloidosis were enrolled in this study after Institutional Review Board approval and obtaining formal written consent. All subjects were imaged head‐first in the supine position in a 1.5T closed‐bore MR imager. 3D MRE was performed using 5 mm isotropic resolution oblique short‐axis slices and a vibration frequency of 140 Hz to obtain global quantitative in vivo left ventricular stiffness measurements. The median stiffness was compared between the two cohorts. An octahedral shear strain signal‐to‐noise ratio (OSS‐SNR) threshold of 1.17 was used to exclude exams with insufficient motion amplitude.

Results

Five volunteers and six patients had to be excluded from the study because they fell below the 1.17 OSS‐SNR threshold. The myocardial stiffness of cardiac amyloid patients (median: 11.4 kPa, min: 9.2, max: 15.7) was significantly higher (P = 0.0008) than normal controls (median: 8.2 kPa, min: 7.2, max: 11.8).

Conclusion

This study demonstrates the feasibility of 3D high‐frequency cardiac MRE as a contrast‐agent‐free diagnostic imaging technique for cardiac amyloidosis.

Level of Evidence: 2

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2017;46:1361–1367.

Abnormal Myocardial Contractility After Pediatric Heart Transplantation by Cardiac MRI

Acute cellular rejection (ACR) compromises graft function after heart transplantation (HTX). The purpose of this study was to describe systolic myocardial deformation in pediatric HTX and to determine whether it is impaired during ACR. Eighteen combined cardiac magnetic resonance imaging (CMR)/endomyocardial biopsy (EMBx) examinations were performed in 14 HTX patients (11 male, age 13.9 ± 4.7 years; 1.2 ± 1.3 years after HTX). Biventricular function and left ventricular (LV) circumferential strain, rotation, and torsion by myocardial tagging CMR were compared to 11 controls as well as between patients with and without clinically significant ACR. HTX patients showed mildly reduced biventricular systolic function when compared to controls [LV ejection fraction (EF): 55 ± 8% vs. 61 ± 3, p = 0.02; right ventricular (RV) EF: 48 ± 7% vs. 53 ± 6, p = 0.04]. Indexed LV mass was mildly increased in HTX patients (67 ± 14 g/m² vs. 55 ± 13, p = 0.03). LV myocardial deformation indices were all significantly reduced, expressed by global circumferential strain (-13.5 ± 2.3% vs. -19.1 ± 1.1%, p < 0.01), basal strain (-13.7 ± 3.0% vs. -17.5 ± 2.4%, p < 0.01), mid-ventricular strain (-13.4 ± 2.7% vs. -19.3 ± 2.2%, p < 0.01), apical strain (-13.5 ± 2.8% vs. -19.9 ± 2.0%, p < 0.01), basal rotation (-2.0 ± 2.1° vs. -5.0 ± 2.0°, p < 0.01), and torsion (6.1 ± 1.7° vs. 7.8 ± 1.1°, p < 0.01). EMBx demonstrated ACR grade 0 R in 3 HTX cases, ACR grade 1 R in 11 HTX cases and ACR grade 2 R in 4 HTX cases. When comparing clinically non-significant ACR (grades 0-1 R vs. ACR 2 R), basal rotation, and apical rotation were worse in ACR 2 R patients (-1.4 ± 1.8° vs. -4.2 ± 1.4°, p = 0.01 and 10.2 ± 2.9° vs. 2.8 ± 1.9°, p < 0.01, respectively). Pediatric HTX recipients demonstrate reduced biventricular systolic function and decreased myocardial contractility. Myocardial deformation indices by CMR may serve as non-invasive markers of graft function and, perhaps, rejection in pediatric HTX patients.

Speckle Tracking and Transthyretin Amyloid Cardiomyopathy

Background

Amyloidosis is a disease caused by deposits of insoluble fibrils in extracellular spaces. The most common type of familial amyloidosis is mediated by mutation of transthyretin, especially Val30Met. Symptoms and ejection fraction decrease may occur in cardiac amyloidosis only in case of poor prognosis. Myocardial strain detected by two-dimensional speckle tracking echocardiography can indicate changes in myocardial function at early stages of the disease.

Objective

To determine the accuracy of left ventricular longitudinal strain by two-dimensional speckle tracking echocardiography in patients with familial amyloidosis caused by Val30Met transthyretin mutation.

Methods

Eighteen consecutive patients, carriers of transthyretin mutation, were evaluated by two-dimensional speckle tracking echocardiography, by which myocardial strain curves were obtained, following the American Society of Echocardiography recommendations.

Results

Patients were divided into three groups: 1- Val30Met with cardiac amyloidosis; 2-Val30Met with extracardiac amyloidosis; 3 - Val30Met without evidence of disease. As the three groups were compared by the Mann-Whitney test, we found a statistically significant difference between groups 1 and 2 in the mean longitudinal tension (p=0.01), mean basal longitudinal strain (p=0.014); in mean longitudinal tension and mean longitudinal strain between groups 1 and 3 (p=0.005); and in the ratio of longitudinal strain of apical septum segment to longitudinal strain of basal septum (p=0.041) between groups 2 and 3.

Conclusion

Left ventricular longitudinal strain detected by two-dimensional speckle tracking echocardiography is able to diagnose left ventricular dysfunction in early stages of familial amyloidosis caused by transthyretin Val30Met mutation.

Phase 2 trial of daily, oral epigallocatechin gallate in patients with light-chain amyloidosis

Previous studies have suggested that an increase in mitochondrial reactive oxygen species may cause organ damage in patients with light-chain (AL) amyloidosis; however, this damage can be decreased by antioxidant-agent treatment. Epigallocatechin gallate (EGCG), the major natural catechin in green tea, has potent antioxidant activity. Because EGCG has recently been reported to have a favorable toxicity profile for treating amyloidosis, we sought to examine the clinical efficacy and toxicity of EGCG in patients with AL amyloidosis. Fifty-seven patients were randomly assigned to the EGCG and observation groups and observed for six months. There were no increases in grade 3-5 adverse events and EGCG therapy was well tolerated. Although a decrease in the urinary albumin level was found in the EGCG group in patients with obvious albuminuria after treatment initiation, its antioxidant activity may not be sufficient to clarify the potential effect of EGCG in patients with AL amyloidosis. Because some of the biological markers responsible for organ damage were well correlated to the level of antioxidant potential in patients' plasma, the status of oxidative stress in the blood may indicate the extent of organ damage in clinical situations.

Anterior Aortic Plane Systolic Excursion: A Novel Indicator of Transplant-Free Survival in Systemic Light-Chain Amyloidosis

BACKGROUND

Anterior aortic plane systolic excursion (AAPSE) was evaluated in the present pilot study as a novel echocardiographic indicator of transplant-free survival in patients with systemic light-chain amyloidosis.

METHODS

Eighty-nine patients with light-chain amyloidosis were included in the post-hoc analysis. A subgroup of 54 patients with biopsy-proven cardiac amyloid infiltration were compared with 41 healthy individuals to evaluate the discriminative ability of echocardiographic findings. AAPSE is defined as the systolic excursion of the anterior aortic margin. To quantify AAPSE, the M-mode cursor was placed on the aortic valve plane in parasternal long-axis view at end-diastole. Index echocardiography had been performed before chemotherapy. Median follow-up duration was 2.4 years. The primary combined end point was heart transplantation or overall death.

RESULTS

Mean AAPSE was 14 ± 2 mm in healthy individuals (mean age=57 ± 10 years; 56% men; BMI=25 ± 4 kg/m²). AAPSE < 11 mm separated patients from age-, gender-, and BMI-matched control subjects with 93% sensitivity and 97% specificity. Median transplant-free survival of patients with AAPSE < 5 mm was 0.7 versus 4.8 years (P = .0001). AAPSE was an independent indicator of transplant-free survival in multivariate Cox regression (echocardiographic model: hazard ratio=0.72 [P = .03]; biomarker model: hazard ratio=0.62 [P = .0001]). Sequential regression analysis suggested incremental power of AAPSE as a marker of transplant-free survival. An ejection fraction-based model with an overall χ² value of 22.8 was improved by the addition of log NT-proBNP (χ² = 32.6, P < .005), troponin-T (χ² = 39.6, P < .01), and AAPSE (χ² = 54.0, P < .0001).

CONCLUSIONS

AAPSE is suggested as an indicator of transplant-free survival in patients with systemic light-chain amyloidosis. AAPSE provided significant incremental value to established staging models.

Neurogenic stunned myocardium in subarachnoid hemorrhage

"Stunned myocardium," characterized by reversible left ventricular dysfunction, was first described via animal models using transient coronary artery occlusion. However, this phenomenon has also been noted with neurologic pathologies and collectively been labeled "neurogenic stunned myocardium" (NSM). Neurogenic stunned myocardium resulting from subarachnoid hemorrhage (SAH) is a challenging pathology due to its diagnostic uncertainty. Traditional diagnostic criteria for NSM after SAH focus on electrocardiographic and echocardiographic abnormalities and troponemia. However, tremendous heterogeneity still exists. Traditional pathophysiological mechanisms for NSM encompassed hypothalamic and myocardial perivascular lesions. More recently, research on pathophysiology has centered on myocardial microvascular dysfunction and genetic polymorphisms. Catecholamine surging as a mechanism has also gained attention with particular focus placed on the role of adrenergic blockade in both the prehospital and acute settings. Management remains largely supportive with case reports acknowledging the utility of inotropes such as dobutamine and milrinone and intra-aortic balloon pump when NSM is accompanied by cardiogenic shock. Neurogenic stunned myocardium that follows SAH can result in many complications such as arrhythmias, pulmonary edema, and prolonged intubation, which can negatively impact long-term recovery from SAH and increase morbidity and mortality. This necessitates the need to accurately diagnose and treat NSM.

Prognosis of Light Chain Amyloidosis With Preserved LVEF: Added Value of 2D Speckle-Tracking Echocardiography to the Current Prognostic Staging System

OBJECTIVES

This study evaluated whether 2-dimensional speckle-tracking echocardiography (2D-STE) has incremental value for prognosis over traditional clinical, echocardiographic, and serological markers-with main focus on the current prognostic staging system-in light-chain (AL) amyloidosis patients with preserved left ventricular ejection fraction.

BACKGROUND

Cardiac amyloidosis (CA) is the major determinant of outcome in AL amyloidosis. The current prognostic staging system is based primarily on serum levels of cardiac troponin T (cTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and free light chain differential (FLC-diff).

METHODS

Consecutive patients with biopsy-proven AL amyloidosis and left ventricular ejection fraction ≥55% were divided into group 1 with CA (n = 63) and group 2 without CA (n = 87). Global longitudinal strain (GLS) by 2D-STE was performed with Vivid E9 (GE Healthcare Co., Milwaukee, Wisconsin) and syngo Velocity Vector Imaging (VVI) software (Siemens Medical Solutions USA, Inc., Malvern, Pennsylvania) (GLS_GE and GLS_VVI, respectively).

RESULTS

Thirty-two deaths (51%) occurred in group 1 and 13 (15%) in group 2 (p ≤ 0.001). Group 1 had thicker walls, lower early diastolic tissue Doppler velocity at septal mitral annulus, and greater left ventricular mass, left atrial volume, glomerular filtration rate, FLC-diff, cTnT, and NT-proBNP (p < 0.001). For the entire cohort, GLS_GE ≥ -14.81, GLS_VVI ≥-15.02, cTnT, NT-proBNP, FLC-diff, age, left ventricular wall thickness, early diastolic tissue Doppler velocity at septal mitral annulus, diastolic dysfunction grade, glomerular filtration rate, deceleration time, and left atrial volume were univariate predictors of death. In a multivariate Cox model, GLS_GE ≥-14.81 (hazard ratio [HR]: 2.68; 95% confidence interval [CI]: 1.07 to 7.13; p = 0.03), FLC-diff, NT-proBNP, and age were independent predictors of survival. There was also a strong trend for GLS_VVI ≥-15.02 (HR: 2.44; 95% CI: 0.98 to 6.33; p = 0.055). Using a nested logistic regression model, GLS_GE (p = 0.03) and GLS_VVI (p = 0.05) provided incremental prognostic value over cTnT, NT-proBNP, and FLC-diff. For survival analysis limited to group 2 (non-CA), GLS_GE and GLS_VVI both predicted all-cause mortality (GLS_GE HR: 1.23; 95% CI: 1.03 to 1.47 [p = 0.02]; GLS_VVI HR: 1.22; 95% CI: 1.01 to 1.49 [p = 0.04], respectively).

CONCLUSIONS

2D-STE predicted outcome and provided incremental prognostic information over the current prognostic staging system, especially in the group without CA.

Alterations in regional myocardial deformation assessed by strain imaging in cardiac amyloidosis

BACKGROUND

Cardiac amyloidosis results in increased left ventricular (LV) wall thickness and diastolic dysfunction (DD). Strain measurements using velocity vector imaging (VVI) may further characterize myocardial dysfunction.

METHODS

A total of 43 AL amyloidosis patients were compared to age-matched normals and hypertensive patients (HT). Subgroup analysis within the amyloid group was performed based on LV wall thickness (≤14 mm, >14 mm) and diastolic dysfunction (DD) (Group 1: normal and impaired relaxation, Group 2: pseudonormal, Group 3: restrictive). LV strain (longitudinal, circumferential, and radial strain (S) and strain rate [Sr]) were measured using velocity vector imaging (VVI).

RESULTS

Increased LV wall thickness and DD were observed in the amyloid group. Global longitudinal (-13.9±4.1% vs -16.7±3.8%; P=.002) and radial (27.4±13.4% vs 38.8±15.7%; P<.001) strain were lower in the amyloid group vs normal controls, while circumferential strain was similar. Segmental analysis demonstrated reduced mid- and basal segmental strain with relative sparing of apical segments in the amyloid group. Reduced longitudinal and radial strain, with preserved circumferential strain, were observed in patients with wall thickness >14 mm; however, circumferential strain was also altered when severe DD (restrictive filling) was present.

CONCLUSION

Reduction in longitudinal and radial S and Sr was evident using VVI strain analysis in amyloidosis, with segmental heterogeneity in longitudinal S. There was relative preservation of circumferential strain, which was reduced only in patients with severe DD.

Prevalence, etiology, and clinical implications of reduced longitudinal systolic strain in renal transplant candidates

AIMS

Reduced global longitudinal systolic strain (GLS) is a common finding in end-stage renal disease (ESRD) patients with normal ejection fraction (EF), and GLS is a stronger predictor of mortality than EF. We sought to determine what factors may be responsible for the decreased strain in this population.

METHODS AND RESULTS

The study group was comprised of 139 renal transplant candidates with a normal EF who had echocardiography with assessment of GLS and basal longitudinal systolic strain (BLS). A GLS of less than -18 and a BLS less than -17 were defined as abnormal. Logistic regression was used to determine variables associated with abnormal GLS and BLS. Of the 139 patients, 49% had abnormal GLS and 70% had abnormal BLS. The univariate predictors of abnormal GLS (P<.05) were low-normal EF, increased interventricular septal thickness (IVS), diabetes, and dihydropyridine calcium channel blocker use. The univariate predictors of abnormal BLS (P<.05) were elevated systolic blood pressure, elevated diastolic blood pressure, elevated heart rate, decreased EF, increased IVS, increased left ventricular posterior wall thickness (LVPW), increased left ventricular mass index, regular dialysis, and clonidine use. On multivariate analysis, low-normal EF (P<.001), increased IVS (P=.024), and diabetes (P=.042) were independent predictors of abnormal GLS, while increased DBP (P=.018), increased LVPW (P=.001), and regular dialysis (P=.006) were independent predictors of abnormal BLS.

CONCLUSIONS

Clinical variables and co-findings beyond EF are associated with abnormal strain measurements and may partially explain the large incidence of abnormal strain in renal transplant candidates.

A Rare Case of Ascites due to Peritoneal Amyloidosis

BACKGROUND

The clinical manifestations of amyloidosis depend on the type of insoluble protein as well as the location of amyloid deposits in tissues or organs. In the gastrointestinal tract, the small intestine is the most common site of amyloid deposits, whereas peritoneal involvement and ascites are rare.

CASE REPORT

We report on a case of ascites due to peritoneal amyloidosis. A 65-year-old patient was admitted to our institution due to anasarca and pulmonary congestion, mimicking heart failure. We started the patient on diuretics and vasodilators. Despite improvement in pulmonary congestion and peripheral edema, his ascites was not reduced. Echocardiogram revealed restrictive cardiomyopathy and a speckle-tracking pattern suggestive of cardiac amyloidosis. Subcutaneous and peritoneal biopsies revealed amyloidosis.

CONCLUSIONS

Amyloidosis is rare in the peritoneum and is usually asymptomatic. Ascites occurs in only 20% of patients with peritoneal amyloidosis. We searched PubMed using "ascites" and "amyloidosis" and identified only eight case reports of amyloidosis with ascites. Physicians should be particularly careful in heart failure and anasarca cases when ascites is disproportional or not responsive to diuretic treatment. To date, there is no specific treatment for peritoneal amyloidosis.

Evaluation of Acute Rejection by Measuring Strain and Strain Rate in Children With Heart Transplant: A Preliminary Report

OBJECTIVES

Asymptomatic rejection after heart transplant is difficult to detect by noninvasive methods. The present study investigated the efficacy of echocardiographic strain and the strain rate imaging method in detecting rejection after pediatric heart transplant.

MATERIALS AND METHODS

Fourteen pediatric patients with heart transplant were examined both with endomyocardial biopsy and strain imaging. Patients were divided into 2 groups: group 1 included patients with rejection, and group 2 included patients without rejection. Patients underwent endomyocardial biopsy at regular intervals. Regional systolic function was evaluated by longitudinal myocardial peak systolic values of strain and of strain rate. Differences between the 2 groups were assessed with unpaired t test or Mann-Whitney U test.

RESULTS

Acute rejection was detected in 7 patients (4 were female patients). Cardiac diagnosis was restrictive cardiomyopathy in 3 patients, dilated cardiomyopathy in 3 patients, and complex congenital heart disease in 1 patient. After heart transplant, 6 patients had rejection once and 1 patient had rejection twice. Evaluation of biopsy samples revealed grade IB rejection in all patients in group 1. Systolic functions of the 6 patients were determined as normal in standard echocardiographic examination. There were no significant differences in deformation and deformation rates between group 1 and 2 except in midseptal region (P < .05).

CONCLUSIONS

One of the most significant complications in patients with heart transplant is rejection. Our results suggested that myocardial strain imaging may be valuable in defining low-grade rejection.

Use of Noninvasive Imaging in Cardiac Amyloidosis

OPINION STATEMENT

Cardiac involvement in amyloidosis is associated with poor outcomes. The standard test for the diagnosis of cardiac amyloidosis is endomyocardial biopsy but given current advances in noninvasive imaging, the diagnosis is frequently obtained or strongly suspected without biopsy. Echocardiography is the most utilized cardiac imaging modality, particularly myocardial strain measures with this modality have been found to be a predictor of clinical outcomes, superior to traditional parameters. Other known imaging modalities with new, useful protocols for this pathology include nuclear imaging and cardiac magnetic resonance (CMR). In particular, CMR has excellent sensitivity and specificity.

Comparison of the standard and speckle tracking echocardiographic features of wild-type and mutated transthyretin cardiac amyloidoses

AIMS

To compare cardiac function in patients with the two types of transthyretin (TTR)-related amyloidoses [wild-type (wt) and mutated (m) TTR amyloidoses (ATTR)] using standard and speckle tracking echocardiography (STE).

METHODS AND RESULTS

Twenty-one consecutive patients with biopsy-proved ATTRwt were compared with 21 patients with ATTRm from the database, matched by age and left ventricular (LV) wall thickness (n = 135, ATTRm). All patients were examined using 2D echocardiography. Apical four- and two-chamber, and long-axis views and basal, mid, and apical short-axis views were used to examine LV longitudinal, circumferential, and radial strains. LV ejection fraction (EF), LV basal circumferential/radial strain, and mid-radial strain were significantly lower in patients with ATTRwt compared with patients with ATTRm. There was no significant difference between the two groups in the other parameters. In the receiver-operating characteristic curve analysis, LVEF and LV basal mean radial strain were the best parameters for distinguishing between the two groups.

CONCLUSION

Patients with ATTRwt are characterized by lower LVEF, LV basal, and LV mid-radial strains compared with patients with ATTRm. LVEF and LV radial strain are useful in distinguishing between ATTRwt and ATTRm when TTR has been proved in biopsy specimens.

Causes and Consequences of Longitudinal LV Dysfunction Assessed by 2D Strain Echocardiography in Cardiac Amyloidosis

OBJECTIVES

The aim of this study was to compare left ventricular longitudinal strain (LS) evaluated by 2-dimensional echocardiography with cardiac magnetic resonance (CMR) in cardiac amyloidosis (CA), establish correlations between histological and imaging findings, and assess the prognostic usefulness of LS measurement and CMR.

BACKGROUND

CA is a condition with a poor prognosis due chiefly to 3 forms of amyloidosis: light-chain amyloidosis (AL), hereditary transthyretin (M-TTR), and wild-type transthyretin (WT-TTR). Two-dimensional echocardiography measurement of LS has been reported to detect early left ventricular systolic dysfunction. The pathophysiological underpinnings, regional distribution, and prognostic significance of LS in CA are unclear.

METHODS

All patients underwent echocardiography, and 53 underwent CMR. The native hearts of the 3 patients who received heart transplants were subjected to histological examination. For each of the 17 left ventricular segments in the American Heart Association model, we evaluated LS, late gadolinium enhancement (LGE) by CMR, and cardiac amyloid deposition. Univariate and multivariate analyses were performed at 6 months to identify variables associated with major adverse cardiac events (MACE).

RESULTS

We studied 79 patients with CA; 26 had AL, 36 M-TTR, and 17 WT-TTR. Mean LS was -10 ± 4%. Both LS and amyloid deposits showed a basal-to-apical gradient. The mean LS and number of segments with LGE were similar across the 3 CA types. LS correlated with LGE and amyloid burden (r = 0.72). LGE was seen in the 6 basal segments in all WT-TTR patients. During the median follow-up of 11 months (range 4 to 17 months), 36 (46%) patients experienced MACE. Independent predictors of MACE were apical LS (cutoff, -14.5%), N-terminal pro-B-type natriuretic peptide (cutoff, 4,000 ng/l), and New York Heart Association functional class III to IV heart failure.

CONCLUSIONS

Basal-to-apical LS abnormalities are similar across CA types and reflect the amyloid burden. Apical LS independently predicts MACE.

Natural history and therapy of TTR-cardiac amyloidosis: emerging disease-modifying therapies from organ transplantation to stabilizer and silencer drugs

Transthyretin-cardiac amyloidoses (ATTR-CA) are an underdiagnosed but increasingly recognized cause of heart failure. Extracellular deposition of fibrillary proteins into tissues due to a variety of inherited transthyretin mutations in ATTRm or due to advanced age in ATTRwt eventually leads to organ failure. In the heart, amyloid deposition causes diastolic dysfunction, restrictive cardiomyopathy with progressive loss of systolic function, arrhythmias, and heart failure. While traditional treatments have consisted of conventional heart failure management and supportive care for systemic symptoms, numerous disease-modifying therapies have emerged over the past decade. From organ transplantation to transthyretin stabilizers (diflunisal, tafamidis, AG-1), TTR silencers (ALN-ATTR02, ISIS-TTR(Rx)), and degraders of amyloid fibrils (doxycycline/TUDCA), the potential for effective transthyretin amyloid therapy is greater now than ever before. In light of these multiple agents under investigation in human clinical trials, clinicians should be familiar with the systemic cardiac amyloidoses, their differing pathophysiology, natural histories, and unique treatment strategies.

Novel strategies for the diagnosis and treatment of cardiac amyloidosis

Systemic amyloidoses are rare, complex diseases caused by misfolding of autologous protein. The presence of heart involvement is the most important prognostic determinant. The diagnosis of amyloid cardiac involvement relies on echocardiography and magnetic resonance imaging, while scintigraphy with bone tracers is helpful in differentiating light chain amyloidosis from other types of amyloidosis involving the heart. Although these diseases are fatal, effective treatments exist that can alter their natural history, provided that they are started before irreversible cardiac damage has occurred. Refined diagnostic techniques, accurate patients' stratification based on biomarkers of cardiac dysfunction, the availability of novel, more powerful drugs, and ultimately, the unveiling of the cellular mechanisms of cardiac damage created a favorable environment for a dramatic improvement in the treatment of this disease that we expect in the next few years.

Left ventricular deformation and torsion assessed by speckle-tracking echocardiography in patients with mutated transthyretin-associated cardiac amyloidosis and the effect of diflunisal on myocardial function

Background

Mutated transthyretin-associated (ATTRm) amyloidosis with heart failure is associated with decreased longitudinal left ventricular (LV) myocardial contraction, as measured by strain Doppler echocardiography. We sought to clarify whether speckle-tracking echocardiography (STE) would provide useful information in patients with ATTRm cardiac amyloidosis.

Methods

One hundred twenty-three consecutive patients with ATTRm amyloidosis were divided into 3 groups. Group 1 had no evidence of cardiac involvement (n = 47), group 2 had heart involvement but no congestive heart failure (CHF) and/or serum brain natriuretic peptide (BNP) levels < 100 pg/mL (n = 35), and group 3 had heart involvement and CHF and/or serum BNP levels ≥ 100 pg/mL (n = 41). All patients underwent standard 2-dimensional (2D), Doppler echo, and STE.

Results

By standard 2D and Doppler echo, differences in parameters were only apparent between group 3 and groups 1 and 2. Global circumferential strains by STE at each LV level and LV torsion were different between group 1 and groups 2 and 3, but not between group 2 and group 3. In contrast, global longitudinal LV strain showed significant intergroup differences (− 17.3 ± 2.3%, − 13.3 ± 2.3%, − 9.9 ± 3.3% for groups 1 to 3, respectively, P < 0.0001). Radial strain also showed significant intergroup differences for each basal LV segment. Among 41 patients who could have been followed up after 1 year, 34 patients with diflunisal treatment had shown improvement in apical rotation and torsion without deterioration in multidirectional strains.

Conclusion

ATTRm cardiac amyloidosis is characterized by progressive impairment in longitudinal and basal LV radial function when global circumferential shortening and torsion remain unchanged.

Cardiac amyloidosis: where are we today?

Systemic amyloidosis is generally considered to be rare, but the heart is frequently involved and is a major determinant of prognosis. New diagnostic imaging methods have recently been developed with the capacity to enhance the accuracy of diagnosis, which will be ever more important with the variety of new treatments on the near horizon. Most cases of cardiac amyloidosis are of either monoclonal immunoglobulin light chain (AL) type, which can occur at any age from young adulthood onwards, or transthyretin (ATTR) type, which can be acquired in elderly individuals or inherited at a younger age. Cardiac involvement is the most serious manifestation of AL amyloidosis, and serum cardiac biomarkers have proved to be of great value in staging disease severity and response to an ever increasing array of chemotherapy agents. Cardiac involvement is the dominant manifestation of nonhereditary ATTR amyloidosis, also known as senile cardiac amyloidosis, the prevalence of which is not known but is probably much greater than currently recognized. A genetic variant in the gene for transthyretin (TTR), which is present in 3-4% of African Americans and probably a similar proportion of black individuals of African descent generally, appears to be associated with increased susceptibility to developing cardiac ATTR amyloidosis in older age. Several novel therapies are in the advanced stages of development for ATTR amyloidosis including TTR protein stabilizers and RNA inhibitors that greatly diminish TTR production. Here, we will review recent developments in the diagnosis and management of cardiac amyloidosis.

Assessment of left ventricular functions with tissue Doppler, strain, and strain rate echocardiography in patients with familial Mediterranean fever

OBJECTIVE

This study assessed the early changes in regional and global systolic and diastolic myocardial functions in patients with familial Mediterranean fever without any cardiovascular symptoms using tissue Doppler and strain and strain rate echocardiography and compared them to the results of a control group.

METHODS

This study has a cross-sectional and observational design. FMF patients with normal left ventricular function were included in the study. We excluded patients who had arrhythmia, acquired/congenital heart disease, pericarditis, or acute attack. We compared 45 children with familial Mediterranean fever on colchicine therapy and 45 age- and sex-matched healthy children.

RESULTS

The 45 patients with familial Mediterranean fever included 24 (55.3%) girls and 21 (46.7%) boys with a mean age of 11.3 ± 3.7 (range 2-18) years. The mean disease duration was 4.6 ± 2.4 (range 0.5-10) years. In the patient group, the homozygous M694V mutation was the most common (64.4%) mutation. The patients with familial Mediterranean fever had statistically lower longitudinal global strain, radial global strain, and strain rates (-14.44 ± 4.77%, 14.80 ± 6.29%, and 0.59 ± 0.24 s, respectively) than the controls (-17.40 ± 1.79%, 17.53 ± 4.63%, and 0.83 ± 0.51 s) (p < 0.05). The circumferential global strain did not differ significantly between the groups.

CONCLUSION

Patients with familial Mediterranean fever who are subclinical from a cardiac aspect might have normal left ventricular function as measured by conventional echocardiography. However, the disease affects their myocardial tissue, and these patients should be followed with conventional, strain, and strain rate echocardiography techniques regularly.

Three-dimensional Speckle Tracking Echocardiography in Light Chain Cardiac Amyloidosis: Examination of Left and Right Ventricular Myocardial Mechanics Parameters

INTRODUCTION AND OBJECTIVES

The study of myocardial mechanics has a potential role in the detection of cardiac involvement in patients with amyloidosis. This study aimed to characterize 3-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics in light chain amyloidosis and examine their relationship with brain natriuretic peptide.

METHODS

In patients with light chain amyloidosis, left ventricular longitudinal and circumferential strain (n=40), and right ventricular longitudinal strain and radial displacement (n=26) were obtained by 3-dimensional-speckle tracking echocardiography. Brain natriuretic peptide levels were determined.

RESULTS

All myocardial mechanics measurements showed differences when compared by brain natriuretic peptide level tertiles. Left and right ventricular longitudinal strain were highly correlated (r=0.95, P<.001). Left ventricular longitudinal and circumferential strain were reduced in patients with cardiac involvement (-9±4 vs -16±2; P<.001, and -24±6 vs -29±4; P=.01, respectively), with the most prominent impairment at the basal segments. Right ventricular longitudinal strain and radial displacement were diminished in patients with cardiac involvement (-9±3 vs -17±3; P<.001, and 2.7±0.8 vs 3.8±0.3; P=.002). On multivariate analysis, left ventricular longitudinal strain was associated with the presence of cardiac involvement (odds ratio = 1.6; 95% confidence interval, 1.04 to 2.37; P=.03) independent of the presence of brain natriuretic peptide and troponin I criteria for cardiac amyloidosis.

CONCLUSIONS

Three-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics are increasingly altered as brain natriuretic peptide increases in light chain amyloidosis. There appears to be a strong association between left ventricular longitudinal strain and cardiac involvement, beyond biomarkers such as brain natriuretic peptide and troponin I.

Principles of transthoracic echocardiographic evaluation

Transthoracic echocardiography is the most widely used imaging test in cardiology. Although completely noninvasive, transthoracic echocardiography has a well-established role in the diagnosis of numerous cardiovascular diseases, and also provides critical qualitative and quantitative information on their prognosis and pathophysiological processes. The aim of this Review is to outline the broad principles of transthoracic echocardiography, including the traditional techniques of two-dimensional, colour, and spectral Doppler echocardiography, and newly developed advances including tissue Doppler, myocardial deformation imaging, torsion, stress echocardiography, contrast and three-dimensional echocardiography. The advantages and disadvantages, clinical application, prognostic value, and salient research findings of each modality are described. Advances in complex imaging techniques are expected to continue unabated, and this Review highlights technical improvements that will influence the diagnosis and improve our understanding of cardiovascular function and disease.

Visual Assessment of Relative Apical Sparing Pattern Is More Useful Than Quantitative Assessment for Diagnosing Cardiac Amyloidosis in Borderline or Mildly Increased Left Ventricular Wall Thickness

BACKGROUND

Relative apical sparing pattern of longitudinal strain (RapSP-LS) was suggested in advanced cardiac amyloidosis (CA). It is unclear whether it is present in less advanced CA.

METHODS AND RESULTS

Patients with presumptive diagnosis of CA and mean left ventricular wall thickness (LVWT) ≤14 mm were recruited. Apart from RapSP-LS visually identified, relative apical longitudinal strain index (RapLSI) was defined as [average apical LS/(average basal LS+average mid-ventricle LS)]. Among 119 patients included, 47 were finally diagnosed with CA. RapLSI was higher in the CA group compared to other causes of increased mean LVWT (P<0.001), but with a significant range of overlap noted. In contrast, RapSP-LS visually assessed was noted in most CA patients (31/47, 66.0%) except in those with preserved LV ejection fraction, normal LVWT, and mildly decreased global LS, suggesting least advanced CA. On multivariate analysis of the added diagnostic role of RapSP-LS or RapLSI on top of clinical, electrocardiographic, and conventional echocardiographic parameters, addition of RapLSI produced only borderline increase in area under the curve of the multivariate model (P=0.05), whereas addition of RapSP-LS significantly increased it (P<0.001).

CONCLUSIONS

Visual identification of RapSP-LS is useful in terms of added diagnostic value compared with quantitative calculation of RapLSI. Its clinical application, however, should be used with caution in patients with less advanced CA.

Strain echocardiography in septic shock - a comparison with systolic and diastolic function parameters, cardiac biomarkers and outcome

Introduction

Myocardial dysfunction is a well-known complication in septic shock but its characteristics and frequency remains elusive. Here, we evaluate global longitudinal peak strain (GLPS) of the left ventricle as a diagnostic and prognostic tool in septic shock.

Methods

Fifty adult patients with septic shock admitted to a general intensive care unit were included. Transthoracic echocardiography was performed on the first day, and repeated during and after ICU stay. Laboratory and clinical data and data on outcome were collected daily from admission and up to 7 days, shorter in cases of death or ICU discharge. The correlation of GLPS to left ventricular systolic and diastolic function parameters, cardiac biomarkers and clinical data were compared using Spearman’s correlation test and linear regression analysis, and the ability of GLPS to predict outcome was evaluated using a logistic regression model.

Results

On the day of admission, there was a strong correlation and co-linearity of GLPS to left ventricular ejection fraction (LVEF), mitral annular motion velocity (é) and to amino-terminal pro-brain natriuretic peptide (NT-proBNP) (Spearman’s ρ -0.70, −0.53 and 0.54, and R² 0.49, 0.20 and 0.24, respectively). In LVEF and NT-proBNP there was a significant improvement during the study period (analysis of variance (ANOVA) with repeated measures, p = 0.05 and p < 0.001, respectively), but not in GLPS, which remained unchanged over time (p = 0.10). GLPS did not correlate to the improvement in clinical characteristics over time, did not differ significantly between survivors and non-survivors (−17.4 (−20.5-(−13.7)) vs. -14.7 (−19.0 - (−10.6)), p = 0.11), and could not predict mortality.

Conclusions

GLPS is frequently reduced in septic shock patients, alone or in combination with reduced LVEF and/or é. It correlates with LVEF, é and NT-proBNP, and remains affected over time. GLPS may provide further understanding on the character of myocardial dysfunction in septic shock.

Echocardiographic assessment of the cardiac amyloidoses

Cardiac amyloidosis is a cardiomyopathy characterized by increased left ventricular (LV) wall thickness and normal or decreased LV cavity size. Congestive heart failure in cardiac amyloidosis is generally considered a predominantly diastolic phenomenon, with systolic dysfunction only occurring in late-stage disease. Echocardiography is a noninvasive, reproducible method of assessing cardiac features and function in cardiac amyloidosis, and some echocardiographic indices are prognostic for the amyloidoses, with M-mode and 2-dimensional echocardiography able to detect increased LV wall thickness. Moreover, Doppler flow measurements can incrementally assess diastolic LV dysfunction, which is characteristic of cardiac amyloidosis, and provide important prognostic information. Additionally, tissue Doppler imaging can detect subtle changes in both systolic and diastolic LV function, which cannot be detected by Doppler flow measurements, and LV longitudinal strain assessed by color tissue Doppler and speckle tracking echocardiography can provide more accurate LV functional and prognostic information than tissue Doppler imaging. This review describes the advances in echocardiography and its crucial role in the diagnosis and management of cardiac amyloidosis.

Impact of long-axis function on cardiac surgical outcomes in patients with radiation-associated heart disease

BACKGROUND

Malignancy-associated thoracic radiation leads to radiation-associated cardiac disease (RACD) that often necessitates cardiac surgery. Myocardial dysfunction is common in patients with RACD. We sought to determine the predictive value of global left ventricular ejection fraction and long-axis function left ventricular global longitudinal strain (LV-GLS) in such patients.

METHODS

We studied 163 patients (age, 63 ± 14 years; 74% women) who had RACD and underwent cardiac surgery (20% had reoperations) between 2000 and 2003. In addition to standard echocardiography, LV-GLS (%) was derived from the average of 18 segments in 3 apical views of the left ventricle, using velocity vector imaging. Standard clinical and demographic parameters were recorded. All-cause mortality was recorded.

RESULTS

The mean duration between cardiac surgery and the last chest radiation was 18 ± 12 years. The median European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 8, and 88 patients died over 6.6 ± 4 years. A total of 52% of patients had ≥ II+ mitral regurgitation; 23% of patients had severe aortic stenosis; and 39% of patients had ≥ II+ tricuspid regurgitation. The mean left ventricular ejection fraction was 54% ± 13%, and the mean LV-GLS was -12.9% ± 4%. In a Cox proportional survival analysis, lower LV-GLS was predictive of mortality in univariable analysis (hazard ratio, 1.07 (95% confidence interval, 1.01-1.14); P = .006); however, after adjustment for other variables, the association became nonsignificant. In patients with a EuroSCORE <median, abnormal LV-GLS (<-14.5%) was associated with significantly higher mortality (48%), compared with those with normal LV-GLS (32%).

CONCLUSIONS

In patients who have RACD and undergo cardiac surgery, LV-GLS does not sufficiently discriminate and is not independently predictive of long-term outcomes. However, in patients with a low EuroSCORE, abnormal LV-GLS was associated with higher mortality, compared with those with normal LV-GLS.

Echocardiographic and biohumoral characteristics in patients with AL and TTR amyloidosis at diagnosis

BACKGROUND

Few studies have analyzed the clinical and echocardiographic differences between light-chain (AL) and transthyretin (TTR) amyloidosis.

HYPOTHESIS

The aim of the present research was to compare, in a real-world setting, the clinical and echocardiographic profiles of these kinds of amyloidosis, at the time of diagnosis, using new-generation echocardiography.

METHODS

Seventy-nine patients with AL and 48 patients with TTR amyloidosis were studied.

RESULTS

According to the criterion of mean left ventricular (LV) thickness >12 mm, 45 AL (C-AL) and all TTR patients had cardiac amyloidotic involvement, whereas 34 AL patients did not. TTR patients had increased right ventricular (RV) and LV chambers with increased RV and LV wall thickness and reduced LV ejection fraction and fractional shortening. Furthermore, TTR patients showed lower N-terminal pro Brain Natriuretic Peptide concentrations and New York Heart Association functional class when compared with C-AL.

CONCLUSIONS

Our data show that at time of first diagnosis, TTR patients have a more advanced amyloidotic involvement of the heart, despite less severe symptoms and biohumoral signs of heart failure. We can hypothesize that we observed different diseases at different stages. In fact, AL amyloidosis is a multiorgan disease with quick progression rate, that becomes rapidly symptomatic, whereas TTR amyloidosis might have a slow progression rate and might remain poorly symptomatic for a greater amount of time.

Ultrasound tissue characterization does not differentiate genotype, but indexes ejection fraction deterioration in becker muscular dystrophy

The aims of the study were, first, to assess whether myocardial ultrasound tissue characterization (UTC) in Becker muscular dystrophy (BMD) can be used to differentiate between patients with deletions and those without deletions; and second, to determine whether UTC is helpful in diagnosing the evolution of left ventricular dysfunction, a precursor of dilated cardiomyopathy. Both cyclic variation of integrated backscatter and calibrated integrated backscatter (cIBS) were assessed in 87 patients with BMD and 70 controls. The average follow-up in BMD patients was 48 ± 12 mo. UTC analysis was repeated only in a subgroup of 40 BMD patients randomly selected from the larger overall group (15 with and 25 without left ventricular dysfunction). Discrimination between BMD patients with and without dystrophin gene deletion was not possible on the basis of UTC data: average cvIBS was 5.2 ± 1.2 and 5.5 ± 1.4 dB, and average cIBS was 29.9 ± 4.7 and 29.6 ± 5.8, respectively, significantly different (p < 0.001) only from controls (8.6 ± 0.5 and 24.6 ± 1.2 dB). In patients developing left ventricular dysfunction during follow-up, cIBS increased to 31.3 ± 5.4 dB, but not significantly (p = 0.08). The highest cIBS values (34.6 ± 5.3 dB, p < 0.09 vs. baseline, p < 0.01 vs BMD patients without left ventricular dysfunction) were seen in the presence of severe left ventricular dysfunction. Multivariate statistics indicated that an absolute change of 6 dB in cIBS is associated with a high probability of left ventricular dysfunction. UTC analysis does not differentiate BMD patients with or without dystrophin gene deletion, but may be useful in indexing left ventricular dysfunction during follow-up.

Noninvasive detection of cardiac involvement in patients with hereditary transthyretin associated amyloidosis using cardiac magnetic resonance imaging: a prospective study

BACKGROUND

Most of the studies that described cardiac amyloidosis using cardiac magnetic resonance (CMR) imaging refer to patients with primary light chain (AL) amyloidosis. The goal of this study was to evaluate cardiac involvement in patients with hereditary transthyretin associated (ATTR) amyloidosis and asymptomatic carriers and its relationships with clinical symptoms and genotype, using CMR imaging.

METHODS AND RESULTS

Fifty-three patients with hereditary ATTR amyloidosis and 14 asymptomatic carriers were included in this study. Morphological, functional and late gadolinium enhancement (LGE) findings were noted on CMR images. A positive LGE suggesting cardiac amyloidosis was detected in 60% of patients. The pattern of LGE was diffuse, focal and circumferential in 32, 26 and 2% of patients, respectively. The inferior basal segment was the most frequently involved (93%) in case of focal involvement. Diffuse pattern was exclusively encountered in patients with cardiac symptoms. Nineteen percent of patients with isolated neurological symptoms and 20% of subjects without left ventricular wall thickening exhibited cardiac abnormalities on CMR.

CONCLUSION

Cardiac involvement can be detected in patients with hereditary ATTR amyloidosis with isolated neurological symptoms and without left ventricular wall thickening, suggesting that CMR could be useful in detecting preclinical cardiac amyloidosis.

Prognostic value of depressed midwall systolic function in cardiac light-chain amyloidosis

BACKGROUND

Cardiac amyloidosis represents an archetypal form of restrictive heart disease, characterized by profound diastolic dysfunction. As ejection fraction is preserved until the late stage of the disease, the majority of patients do fulfill the definition of diastolic heart failure, that is, heart failure with preserved ejection fraction (HFpEF). In another clinical model of HFpEF, that is, pressure-overload hypertrophy, depressed midwall fractional shortening (mFS) has been shown to be a powerful prognostic factor.

OBJECTIVE AND METHODS

To assess the potential prognostic role of mFS in cardiac light-chain amyloidosis with preserved ejection fraction, we enrolled 221 consecutive untreated patients, in whom a first diagnosis of cardiac light-chain amyloidosis was concluded between 2008 and 2010. HFpEF was present in 181 patients. Patients in whom cardiac involvement was excluded served as controls (n = 121). Prognosis was assessed after a median follow-up of 561 days.

RESULTS

When compared with light-chain amyloidosis patients without myocardial involvement, cardiac light-chain amyloidosis was characterized by increased wall thickness (P <0.001), reduced end-diastolic left ventricular volumes (P <0.001), and diastolic dysfunction (P <0.001). In patients with preserved ejection fraction, mFS was markedly depressed [10.6% (8.7-13.5) vs. 17.8% (15.9-19.5) P <0.001]. At multivariable analysis, mFS, troponin I, and NT-pro-brain natriuretic peptide were the only significant prognostic determinants (P <0.001), whereas other indices of diastolic (E/E' ratio, transmitral and pulmonary vein flow velocities) and systolic function (tissue Doppler systolic indices, ejection fraction), or the presence/absence of congestive heart failure did not enter the model.

CONCLUSION

In cardiac light-chain amyloidosis with normal ejection fraction, depressed circumferential mFS, a marker of myocardial contractile dysfunction, is a powerful predictor of survival.