Amyloid heart disease mimicking hypertrophic cardiomyopathy

Imaging in Heart Failure with Preserved Ejection Fraction: A Multimodality Imaging Point of View

Heart failure with preserved ejection fraction (HFpEF) is an important global health problem. Despite increased prevalence due to improved diagnostic options, limited improvement has been achieved in cardiac outcomes. HFpEF is an extremely complex syndrome and multimodality imaging is important for diagnosis, identifying its different phenotypes and determining prognosis. Evaluation of left ventricular filling pressures using echocardiographic diastolic function parameters is the first step of imaging in clinical practice. The role of echocardiography is becoming more popular and with the recent developments in deformation imaging, cardiac MRI is extremely important as it can provide tissue characterisation, identify fibrosis and optimal volume measurements of cardiac chambers. Nuclear imaging methods can also be used in the diagnosis of specific diseases, such as cardiac amyloidosis.

Multimodality imaging approach to cardiac amyloidosis: part 2

With recent advances in cardiac imaging, genetics, and treatment options, cardiac amyloidosis (CA) is now recognized as an important and under diagnosed condition contributing to cardiovascular morbidity and mortality. Although still considered a rare disease, CA is now recognized as an important contributor to heart failure with preserved ejection fraction (HFPEF) and low gradient aortic stenosis, two important conditions commonly faced in clinical practice. This review uses clinical scenarios to highlight the complementary role of traditional imaging tools such as electrocardiogram (ECG) and echocardiography (echo) in conjunction with advanced cardiac imaging with cardiac magnetic resonance (CMR) and nuclear cardiac scintigraphy using bone avid tracers in the comprehensive workup of CA. We also highlight the importance of workup of light chain disease as part of integration of imaging findings and discuss the key aspects of various imaging modalities. Finally, an algorithm integrating clinical suspicion, laboratory testing, and imaging in the workup of CA is presented.

Cardiac Amyloidosis: Overlooked, Underappreciated, and Treatable

Cardiac amyloidosis (CA) is an infiltrative and restrictive cardiomyopathy that leads to heart failure, reduced quality of life, and death. The disease has two main subtypes, transthyretin cardiac amyloidosis (ATTR-CA) and immunoglobulin light chain cardiac amyloidosis (AL-CA), characterized by the nature of the infiltrating protein. ATTR-CA is further subdivided into wild-type (ATTRwt-CA) and variant (ATTRv-CA) based on the presence or absence of a mutation in the transthyretin gene. CA is significantly underdiagnosed and increasingly recognized as a cause of heart failure with preserved ejection fraction. Advances in diagnosis that employ nuclear scintigraphy to diagnose ATTR-CA without a biopsy and the emergence of effective treatments, including transthyretin stabilizers and silencers, have changed the landscape of this field and render early and accurate diagnosis critical. This review summarizes the epidemiology, pathophysiology, diagnosis, prognosis, and management of CA with an emphasis on the significance of recent developments and suggested future directions.

Transthyretin amyloid cardiomyopathy in women: frequency, characteristics, and diagnostic challenges

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, life-threatening disease characterized by deposition of insoluble amyloid fibrils in the myocardium, resulting in cardiac structural and functional abnormalities and ultimately heart failure. Disease frequency is reportedly lower in women than men, but sex-related differences have not been well established. We conducted a systematic literature review (SLR), based on PRISMA-P guidelines and registered with PROSPERO, to assess whether the epidemiology and clinical presentation of ATTR-CM differ between women and men. MEDLINE, Embase, and Cochrane databases and selected conference proceedings were searched (August 16, 2019) to identify observational and clinical studies reporting sex-specific data for patients with wild-type or hereditary ATTR-CM. Of 193 publications satisfying final eligibility criteria, 69 studies were included in our pooled analysis. Among the 4669 patients with ATTR-CM analyzed, 791 (17%) were women, including 174 (9%), 366 (29%), and 251 (18%) in studies of wild-type, hereditary, and undefined ATTR-CM, respectively. Data available on disease characteristics were limited and very heterogeneous, but trends suggested some cardiac structural/functional differences, i.e., lower interventricular septal and posterior wall thickness and left ventricular (LV) end diastolic diameter, and higher LV ejection fractions, in women versus men across ATTR-CM subtypes. Because LV wall thickness > 12 mm is generally the suggested threshold for ATTR-CM diagnosis in both sexes, smaller cardiac anatomy in women with the disease may lead to underdiagnosis. Additional research and studies are needed to elucidate potential disparities between sexes in ATTR-CM frequency, clinical characteristics, and underlying biological mechanisms. This study was registered within the International Prospective Register of Systematic Reviews (PROSPERO) database of the University of York (CRD42019146995).

Cardiac AA amyloidosis in a patient with obstructive hypertrophic cardiomyopathy

Cardiac amyloid A (AA) amyloidosis is rare. We present the case of a 72-year-old woman with obstructive hypertrophic cardiomyopathy (HCM) and biopsy-proven renal AA amyloidosis whose dyspnea and exercise intolerance had worsened over the previous year. Her AA amyloidosis was suspected to be secondary to chronic diverticulitis for which she had undergone hemicolectomy and sigmoidectomy 3 years prior. Echocardiographic findings were consistent with worsening left ventricular outflow tract obstruction at rest. Cardiac magnetic resonance imaging revealed patchy areas of midwall late gadolinium enhancement. Right ventricular endomyocardial biopsy did not reveal amyloid deposition, and cardiac technetium-99m pyrophosphate scintigraphy did not suggest transthyretin amyloidosis. The patient underwent septal myectomy with resection of an accessory papillary muscle. Pathological examination of the myectomy specimen was consistent with HCM. In addition, there was a thick layer of diffuse endocardial and vascular amyloid deposition that was identified as AA type by laser-microdissection with liquid chromatography-coupled tandem-mass spectrometry. This case report highlights the presence of 2 distinct disease processes occurring simultaneously and the importance of tissue diagnosis of AA amyloidosis, a condition that is not commonly associated with HCM.

Hypoxia and Inflammation as a Consequence of β-Fibril Accumulation: A Perspective View for New Potential Therapeutic Targets

Amyloidoses are heterogeneous diseases that result from the deposition of toxic insoluble β-sheet fibrillar protein aggregates in different tissues. The cascade of molecular events leading to amyloidoses and to the related clinical manifestations is not completely understood. Nevertheless, it is known that tissue damage associated to this disease involves alteration of tissue architecture, interaction with cell surface receptors, inflammation elicited by the amyloid protein deposition, oxidative stress, and apoptosis. However, another important aspect to consider is that systemic protein massive deposition not only subverts tissue architecture but also determines a progressive cellular hypertrophy and dilation of the extracellular space enlarging the volume of the organ. Such an alteration increases the distance between cells and vessels with a drop in pO₂ that, in turn, causes both necrotic cell death and activation of the hypoxia transcription factor HIF-1α. Herewith, we propose the hypothesis that both cell death and hypoxia represent two important events for the pathogenesis of damage and progression of amyloidoses. In fact, molecules released by necrotic cells activate inflammatory cells from one side while binding to HIF-1α-dependent membrane receptors expressed on hypoxic parenchymal cells on the other side. This latter event generates a signaling cascade triggering NFκB activation and chronic inflammation. Finally, we also suggest that this scenario, once proved and detailed, might suggest important targets for new therapeutic interventions.

Diagnosis and Management of a Cardiac Amyloidosis Case Mimicking Hypertrophic Cardiomyopathy

Cardiac amyloidosis is an acquired heart disease secondary to the deposition of β-pleated amyloid proteins in heart tissue. Amyloid light chain (AL) amyloidosis is usually secondary to multiple myeloma and can rapidly deteriorate cardiac function, with high mortality. Up to 50% of AL patients have cardiac involvement presenting as heart failure, conduction abnormalities, and cardiomyopathies. One of the rare presentations is the likely simulation of disease with hypertrophic cardiomyopathies like left ventricular outflow tract (LVOT) obstruction due to the systolic anterior motion of the mitral valve and irregular septal hypertrophy secondary to amyloid deposits. We present a case of cardiac amyloidosis secondary to multiple myeloma who presented with dynamic LVOT obstruction resembling hypertrophic obstructive cardiomyopathy and complicated by acute pulmonary edema. These complicated cases can be initially treated for pulmonary edema with an elevation of the head of the bed, furosemide, and nitroglycerin intravenously. For multiple myeloma, chemotherapy was continued. Beta-blockers, calcium channel blockers and angiotensin-converting enzyme inhibitors, and aldosterone receptor blocker were avoided due to poor tolerability. After symptomatic control, the patient can likely be scheduled for septal myotomy and the placement of a pacemaker or implantable cardiac defibrillator to prevent any arrhythmias causing sudden cardiac death in these subsets of patients.

Hiding in plain sight: a brain lesion in a patient with a history of colon and breast cancer

We present a case of a 76-year-old woman who was admitted to our hospital with a low Glasgow Coma Scale score. She had a medical history of breast and colon cancer. The CT scan showed possible diagnosis of brain metastasis. However, the MRI scan showed this to be a completely different diagnosis.

Cardiac amyloidosis: The great masquerader

Cardiac amyloidosis is an elusive condition that is notorious for mimicking various cardiovascular conditions that present with left ventricular hypertrophy (LVH). The hypertrophy in amyloidosis is typically diffuse; however, rare reports of echocardiographic resemblances with hypertrophic cardiomyopathy (HCM) exist, such as asymmetric septal hypertrophy and left ventricular outflow tract obstruction. Cardiac MRI can help differentiate amyloidosis from hypertrophic cardiomyopathy in unclear situations. This differentiation from HCM and other forms of cardiomyopathy has important treatment implications. Here we present the case of a 76-year-old man with cardiomyopathy who had echocardiographic features of asymmetric hypertrophic cardiomyopathy but was correctly diagnosed with amyloidosis with the help of cardiac MRI and ECG.

Transthyretin amyloidosis: a phenocopy of hypertrophic cardiomyopathy

OBJECTIVES

Hypertrophic cardiomyopathy (HCM) is an inherited cardiac disorder that affects over one in 500 persons worldwide. The autosomal dominant transmission of HCM implies that many relatives are at risk for HCM associated morbidity and mortality, therefore genetic testing and counselling is of great importance. However, in only 50-60% of the patients a mutation is found, which hampers predictive genetic testing in relatives. In HCM patients in whom the causal mutation has not been identified (yet), phenocopies of HCM - i.e. diseases that mimic HCM - could be responsible for the HCM phenotype. One of the HCM phenocopies is transthyretin amyloidosis (ATTR), caused by mutations in the transthyretin (TTR) gene.

METHODS

From 697 HCM index patients referred to our cardiogenetics outpatient clinic and tested for HCM associated genes between January 1997 and December 2012, we selected the ones without a detected causal mutation (n = 345). In these patients, additional DNA analysis of the TTR gene was performed.

RESULTS

In four patients (1.2%), a TTR mutation was detected (E7G, V30M, T119M, V122I). The E7G mutation is probably a non-pathogenic mutation. The T119M mutation is a known TTR mutation, but does not cause a cardiac phenotype. So in two (0.6%) patients, TTR analysis identified the cause of their HCM.

CONCLUSIONS

ATTR should always be considered in patients with unexplained HCM, especially because of the great benefit of an early diagnosis regarding treatment and prognosis.

Progression of myocardial sympathetic denervation assessed by 123I-MIBG imaging in familial amyloid polyneuropathy and the effect of liver transplantation

INTRODUCTION

Familial amyloid polyneuropathy (FAP) is a rare disease caused by systemic deposition of amyloidogenic variants of the transthyretin (TTR) protein. The TTR-V30M mutation is caused by the substitution of valine by methionine at position 30 and mainly affects the peripheral and autonomic nervous systems. Cardiovascular manifestations are common and are due to autonomic denervation and to amyloid deposition in the heart. Cardiac sympathetic denervation detected by iodine-123 labeled metaiodobenzylguanidine (MIBG) is an important prognostic marker in TTR-V30M FAP. Liver transplantation, widely used to halt neurological involvement, appears to have a varying effect on the progression of amyloid cardiomyopathy. Its effect on the progression of cardiac denervation remains unknown.

METHODS

In this observational study, patients with the TTR-V30M mutation underwent annual cardiac assessment and serial MIBG imaging with quantification of the late heart-to-mediastinum (H/M) ratio.

RESULTS

We studied 232 patients (median age 40 years, 54.7% female, 37.9% asymptomatic at the time of inclusion) who were followed for a median of 4.5 years and underwent a total of 558 MIBG scans. During follow-up, 47 patients (20.3%) died. MIBG scintigraphy at inclusion was a strong predictor of prognosis, with the risk of death increasing by 27.8% for each one-tenth reduction in the late H/M ratio. The late H/M ratio decreased with age (0.082/year, p<0.001), but progression of cardiac denervation was so slow that annual repetition of MIBG imaging did not increase its prognostic accuracy. During follow-up, 70 symptomatic patients underwent liver transplantation. The late H/M ratio decreased by 0.19/year until transplantation but no statistically significant differences were detected after the procedure.

CONCLUSIONS

Cardiac denervation is common during the progression of TTR-V30M FAP and quantification of the late H/M ratio on MIBG scintigraphy is valuable for prognostic stratification of these patients. Liver transplantation stabilizes cardiac denervation, without recovery or further deterioration in cardiac MIBG uptake after the procedure.

Prevalence and clinical phenotype of hereditary transthyretin amyloid cardiomyopathy in patients with increased left ventricular wall thickness

AIMS

Increased left ventricular wall thickness (LVWT) is a common finding in cardiology. It is not known how often hereditary transthyretin-related familial amyloid cardiomyopathy (mTTR-FAC) is responsible for LVWT. Several therapeutic modalities for mTTR-FAC are currently in clinical trials; thus, it is important to establish the prevalence of TTR mutations (mTTR) and the clinical characteristics of the patients with mTTR-FAC.

METHODS AND RESULTS

In a prospective multicentre, cross-sectional study, the TTR gene was sequenced in 298 consecutive patients diagnosed with increased LVWT in primary cardiology clinics in France. Among the included patients, median (25-75th percentiles) age was 62 [50;74]; 74% were men; 23% were of African origin; and 36% were in NYHA Class III-IV. Median LVWT was 18 (16-21) mm. Seventeen (5.7%; 95% confidence interval [CI]: [3.4;9.0]) patients had mTTR of whom 15 (5.0%; 95% CI [2.9;8.2]) had mTTR-FAC. The most frequent mutations were V142I (n = 8), V50M (n = 2), and I127V (n = 2). All mTTR-FAC patients were older than 63 years with a median age of 74 [69;79]. Of the 15 patients with mTTR-FAC, 8 were of African descent while 7 were of European descent. In the African descendants, mTTR-FAC median age was 74 [72;79] vs. 55 [46;65] years in non-mTTR-FAC (P < 0.001). In an adjusted multivariate model, African origin, neuropathy, carpal tunnel syndrome, electrocardiogram (ECG) low voltage, and late gadolinium enhancement (LGE) at cardiac-magnetic resonance imaging were all independently associated with mTTR-FAC.

CONCLUSION

Five per cent of patients diagnosed with hypertrophic cardiomyopathy have mTTR-FAC. Mutated transthyretin genetic screening is warranted in elderly subjects with increased LVWT, particularly, those of African descent with neuropathy, carpal tunnel syndrome, ECG low voltage, or LGE.

Can echocardiography and ECG discriminate hereditary transthyretin V30M amyloidosis from hypertrophic cardiomyopathy?

OBJECTIVE

Hereditary transthyretin (ATTR) amyloidosis with increased left ventricular wall thickness could easily be misdiagnosed by echocardiography as hypertrophic cardiomyopathy (HCM). Our aim was to create a diagnostic tool based on echocardiography and ECG that could optimise identification of ATTR amyloidosis.

METHODS

Data were analysed from 33 patients with biopsy proven ATTR amyloidosis and 30 patients with diagnosed HCM. Conventional features from ECG were acquired as well as two dimensional and Doppler echocardiography, speckle tracking derived strain and tissue characterisation analysis. Classification trees were used to select the most important variables for differentiation between ATTR amyloidosis and HCM.

RESULTS

The best classification was obtained using both ECG and echocardiographic features, where a QRS voltage >30 mm was diagnostic for HCM, whereas in patients with QRS voltage <30 mm, an interventricular septal/posterior wall thickness ratio (IVSt/PWt) >1.6 was consistent with HCM and a ratio <1.6 supported the diagnosis of ATTR amyloidosis. This classification presented both high sensitivity (0.939) and specificity (0.833).

CONCLUSION

Our study proposes an easily interpretable classification method for the differentiation between HCM and increased left ventricular myocardial thickness due to ATTR amyloidosis. Our combined echocardiographic and ECG model could increase the ability to identify ATTR cardiac amyloidosis in clinical practice.

Molecular genetics in hypertrophic cardiomyopathy: towards individualized management of the disease

Hypertrophic cardiomyopathy is a relatively common genetic disease, affecting one person per 500 in the general population, and is clinically defined by the presence of unexplained left ventricular hypertrophy. Although recognized as the most common cause of sudden death in the young (especially in athletes), the cardiac expression of the disease is highly variable with respect to age at onset, degree of symptoms and risk of cardiac death. As a consequence, therapeutic strategies are diverse and must be adapted to the specific features of an individual. Recently, the molecular bases of the disease have been unraveled with the identification of a large number of mutations in genes encoding sarcomeric proteins. This review focuses on the impact of the molecular data on the understanding of the disease, and considers the emerging issues regarding the impact of molecular testing on the management of patients (or relatives) in clinical practice.

Modulators of amyloid protein aggregation and toxicity: EGCG and CLR01

Abnormal protein folding and self-assembly causes over 30 cureless human diseases for which no disease-modifying therapies are available. The common side to all these diseases is formation of aberrant toxic protein oligomers and amyloid fibrils. Both types of assemblies are drug targets, yet each presents major challenges to drug design, discovery, and development. In this review, we focus on two small molecules that inhibit formation of toxic amyloid protein assemblies — the green-tea derivative (−)-epigallocatechin-3-gallate (EGCG), which was identified through a combination of epidemiologic data and a compound library screen, and the molecular tweezer CLR01, whose inhibitory activity was discovered in our group based on rational reasoning, and subsequently confirmed experimentally. Both compounds act in a manner that is not specific to one particular protein and thus are useful against a multitude of amyloidogenic proteins, yet they act via distinct putative mechanisms. CLR01 disrupts protein aggregation through specific binding to lysine residues, whereas the mechanisms underlying the activity of EGCG are only recently beginning to unveil. We discuss current in vitro and, where available, in vivo literature related to EGCG and CLR01’s effects on amyloid β-protein, α-synuclein, transthyretin, islet amyloid polypeptide, and calcitonin. We also describe the toxicity, pharmacokinetics, and mechanism of action of each compound.

THAOS - The Transthyretin Amyloidosis Outcomes Survey: initial report on clinical manifestations in patients with hereditary and wild-type transthyretin amyloidosis

BACKGROUND

Transthyretin (TTR) amyloidosis is a rare, life-threatening, systemic, autosomal dominant condition occurring in adults, with two main forms: hereditary (associated with TTR gene mutations) and wild-type. Studies indicate considerable heterogeneity in disease presentation, with predominantly polyneuropathic, predominantly cardiac, or mixed phenotypes.

METHODS

THAOS - the Transthyretin Amyloidosis Outcomes Survey - is the first global, multicenter, longitudinal, observational survey that collects data on the natural history of TTR amyloidosis (ClinicalTrials.gov: NCT00628745). This paper presents data on signs and symptoms, neurological and cardiac assessments, biomarkers and quality of life in the patients enrolled in THAOS from its inception in December 2007 to September 2011.

RESULTS

At the time of this analysis, data were available from 611 symptomatic patients with hereditary TTR amyloidosis, 67 symptomatic patients with wild-type TTR amyloidosis, and 274 currently asymptomatic individuals with a TTR mutation. Nineteen countries were participating in the registry. The largest patient groups came from Portugal (n = 453), the USA (n = 129), Italy (n = 70), and Japan (n = 68). Predominant symptom presentation in patients with hereditary TTR amyloidosis differed according to the underlying disease-causing mutation (polyneuropathy for Val30Met, cardiomyopathy for Val122Ile and Leu111Met, and mixed for Glu89Gln). However, each mutation was associated with clear multisystem involvement. Similarly, although cardiomyopathy was predominant in patients with wild-type TTR amyloidosis, many also showed symptoms consistent with neuropathy. Quality of life in patients with hereditary TTR amyloidosis, but not asymptomatic carriers of disease-causing mutations, was severely impaired relative to that of the age-matched general US population.

CONCLUSIONS

This preliminary analysis highlights the considerable phenotypic heterogeneity for neurological and cardiac manifestations in patients with hereditary and wild-type TTR amyloidosis and the necessity of providing multidisciplinary care. THAOS registry data will help better characterize the diverse presentation and course of TTR amyloidosis worldwide and aid in improving and standardizing diagnosis and treatment.

Green tea halts progression of cardiac transthyretin amyloidosis: an observational report

Background

Treatment options in patients with amyloidotic transthyretin (ATTR) cardiomyopathy are limited. Epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea (GT), inhibits fibril formation from several amyloidogenic proteins in vitro. Thus, it might also halt progression of TTR amyloidosis. This is a single-center observational report on the effects of GT consumption in patients with ATTR cardiomopathy.

Methods

19 patients with ATTR cardiomyopathy were evaluated by standard blood tests, echocardiography, and cardiac MRI (n = 9) before and after consumption of GT and/or green tea extracts (GTE) for 12 months.

Results

Five patients were not followed up for reasons of death (n = 2), discontinuation of GT/GTE consumption (n = 2), and heart transplantation (n = 1). After 12 months no increase of left ventricular (LV) wall thickness and LV myocardial mass was observed by echocardiography. In the subgroup of patients evaluated by cardiac MRI a mean decrease of LV myocardial mass (−12.5 %) was detected in all patients. This was accompanied by an increase of mean mitral annular systolic velocity of 9 % in all 14 patients. Total cholesterol (191.9 ± 8.9 vs. 172.7 ± 9.4 mg/dL; p < 0.01) and LDL cholesterol (105.8 ± 7.6 vs. 89.5 ± 8.0 mg/dL; p < 0.01) decreased significantly during the observational period. No serious adverse effects were reported by any of the participants.

Conclusions

Our observation suggests an inhibitory effect of GT and/or GTE on the progression of cardiac amyloidosis. We propose a randomized placebo-controlled investigation to confirm our observation.

Electronic supplementary material

The online version of this article (doi:10.1007/s00392-012-0463-z) contains supplementary material, which is available to authorized users.

[The various forms of left ventricular hypertrophy: diagnostic value of echocardiography]

Left ventricular hypertrophy is a non-specific physiological or maladaptive cardiac response to a large array of stimuli mediated by exercise and numerous cardiac and systemic diseases. The precise characterization and quantification of left ventricular hypertrophy may allow a more timely diagnosis of the underlying condition. The clinical reference standard to assess left ventricular hypertrophy is echocardiography, but a comprehensive description of how to approach this frequent finding in clinical practice is lacking. The current review systematically describes the typical echocardiographic patterns of important types of cardiac hypertrophy using both established and advanced imaging modalities. In hypertrophic obstructive cardiomyopathy a markedly reduced regional systolic function is found in the prominent thickened septum, whereas in essential arterial hypertension a typical concentric left ventricular hypertrophy with a less prominent basal septal bulge is present. The echocardiographic characteristics of cardiac amyloidosis are ventricular hypertrophy with sparkling granular myocardial texture and a small epicardial effusion. In addition, the strain rate curve for longitudinal function shows a typically reduced function which reaches maximum already in early systole. The typical feature of Friedreich cardiomyopathy is concentric left ventricular hypertrophy and sparkling granular texture with preserved regional systolic function. In Fabry cardiomyopathy a prominent papillary muscle is presented and a typical strain rate curve can be extracted from the basal lateral wall, indicating replacement fibrosis. Prominent hypertrabecularisation (ratio of non-compacted to compacted myocardium >2) in the apical and mid left ventricular segments is typical for non-compaction cardiomyopathy. Knowledge of these typical echocardiographic features enables the cardiologist to distinguish between the different hypertrophic entities, thus paving the way to early diagnosis.

Development of cardiomyopathy after liver transplantation in Swedish hereditary transthyretin amyloidosis (ATTR) patients

BACKGROUND

Recent studies of liver transplanted (LTx) familial amyloidotic polyneuropathy (FAP) patients have shown a progression of cardiomyopathy in some patients after LTx, but knowledge of the underlying factors remains limited.

METHODS

Seventy-five patients, who had undergone LTx from 1996 to 2008, were included. They had all been examined by echocardiography 1-16 months before LTx. Fifty-four had been re-examined 7-34 months, and forty-two 36-137 months after LTx.

RESULTS

A significant increase in interventricular septum (IVS) thickness occurred after LTx (p < 0.01), particularly in males (p = 0.002) and late onset patients (p = 0.003). The development of post-LTx cardiomyopathy was related to patient's age at onset of the disease, male gender and pre-LTx IVS thickness. On multivariate regression analysis, however, age at onset was the only significant predictor for the development of cardiomyopathy (odds ratio = 1.14, 95% confident interval 1.01-1.30, p = 0.04).

CONCLUSION

An increase of IVS thickness can be observed in FAP patients after LTx. Age at onset of the disease is the main predictor for increased IVS thickness and for the development of cardiomyopathy after liver transplantation.

Left ventricular torsion by two-dimensional speckle tracking echocardiography in patient with a-type amyloid heart disease

Amyloidosis is a clinical disorder caused by extracellular and or intracellular deposition of insoluble abnormal amyloid fibrils that alter the normal function of tissues. Amyloid A amyloidosis is the most common form of systemic amyloidosis worldwide The heart may be affected in systemic AL amyloidosis, but also more rarely in A amyloidosis. In this report, we presented a patient with A-type amyloid heart disease who had dynamic left ventricular outflow tract obstruction mimicking hypertrophic obstructive cardiomyopathy. We also investigated left ventricular torsion, untwisting rate and left ventricular longitudinal global strain by two-dimensional speckle tracking echocardiography.

Report of five rare or previously unknown amyloidogenic transthyretin mutations disclosed in Sweden

The number of amyloidogenic transthyretin (TTR) mutations described in the literature is more than 100. However, for several mutations, the phenotype has been described in a few individuals only; thus, the knowledge of the clinical course and the outcome after therapeutical interventions such as liver transplantation is limited. We describe the phenotype associated with five rare amyloidogenic TTR mutations that lately were discovered in Sweden: ATTR Val30Leu, Ala45Ser, Leu55Gln, Gly57Arg and Tyr69His of which ATTR Gly57Arg is previously unknown. The symptoms at onset differed, but cardiomyopathy and peripheral neuropathy were observed in all except the ATTR Tyr69His mutation. Likewise, carpal tunnel syndrome was found or had been present in all cases except the case with the ATTR Val30Leu mutation. The phenotype of the ATTR Tyr69His mutation was characterised by oculo-meningeal symptoms with seizures and a steadily progressing dementia, symptoms rarely found in ATTR amyloidosis, but similar to those previously described for this mutation, where all cases appear to originate from one Swedish family. Two patients with the ATTR Leu55Gln and Ala45Ser mutations have been subjected to liver transplantation, but echocardiographic examination has revealed an increasing cardiomyopathy after transplantation in both cases, the ATTR Leu55Gln patient succumbed 2 years after transplantation from progressive disease.

Light-chain amyloidosis with echocardiographic features of hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy and cardiac amyloidosis result in thickening of the left ventricle, as visualized by 2-dimensional echocardiography. Hemodynamically, hypertrophic cardiomyopathy can be typified by a left ventricular outflow tract gradient and systolic anterior motion of the mitral apparatus, findings rarely seen in cardiac amyloidosis. This case series reports 4 patients with cardiac light-chain amyloidosis and left ventricular outflow tract obstruction at rest, suggesting that there may be echocardiographic overlap between these 2 disparate disease processes. In a series of consecutive patients with cardiac light-chain amyloidosis over a 2-year period, the prevalence of these echocardiographic findings was approximately 4%. In conclusion, awareness of this overlap in echocardiographic presentation may permit more accurate diagnosis, particularly at early stages of amyloid disease, when more treatment options exist.

Familial amyloidosis in a large Spanish kindred resulting from a D38V mutation in the transthyretin gene

BACKGROUND

Transthyretin amyloidosis, also known as familial amyloidotic polyneuropathy, is an autosomal dominant disorder that results from a mutation in the gene encoding plasma transthyretin (TTR). Distinct clinical presentations of the disease have been related so far to different point mutations, polyneuropathy being the predominant clinical feature in the majority of cases. Nevertheless, misdiagnosis of familial forms of amyloidosis is still common.

MATERIALS AND METHODS

A 71-year-old man was admitted to our hospital for heart failure. He had been previously diagnosed of AL amyloidosis with predominant polyneuropathic, cardiac and laryngeal involvement on the basis of clinical data and amyloid deposition in tissue specimens. During admission, suspicion of transthyretin amyloidosis was raised due to the absence of renal involvement, monoclonal protein and plasma cell dyscrasia. Complete clinical evaluation and sequence analysis of the TTR gene of the patient and his family were performed.

RESULTS

Gene sequence analysis revealed a rare A-to-T transition in exon 2 resulting in the substitution of aspartic acid by valine at position 38 (D38V) in the index case and in two other members of the family. Clinical study of the kindred showed a predominant late-onset heart involvement with variable polyneuropathy.

CONCLUSIONS

Here we report a large pedigree from Spain with three members affected by a severe late-onset form of amyloidosis due to a rare D38V TTR mutation. The variations on the natural history of this form of amyloidosis may have important consequences on genetic counselling, follow-up, and therapeutic approaches for these patients.