Outcomes of Restrictive Cardiomyopathy in Japanese Children　- A Retrospective Cohort Study.

BACKGROUND: There has been no nationwide survey on the prognosis of pediatric restrictive cardiomyopathy (RCM) in Japan; therefore, this retrospective multicentered study was designed to investigate the long-term survival rate of pediatric patients with RCM in Japan.Methods and Results: A multicentered, retrospective observational study was performed between 1990 and 2014 and included patients diagnosed with RCM who were aged <18 years from 18 Japanese institutions. A total of 54 patients were diagnosed with RCM. The median age at diagnosis was 4.4 years, and the median duration of observation was 2.2 years at the time of this study. Of these patients, 54% had symptoms, including heart failure. Twelve patients died without heart transplantation, mostly due to heart failure. The median time to death from diagnosis was 2.5 years. Freedom from death at 1, 5, and 10 years was 91%, 68%, and 62%, respectively. Death occurred within 5 years of diagnosis in most patients. Twenty-two patients underwent heart transplantation. Freedom from heart transplantation at 1, 5, and 10 years was 77%, 58%, and 53%, respectively. Freedom from death or heart transplantation at 1, 5, and 10 years was 72%, 40%, and 34%, respectively. The presence of symptoms was a risk factor for death or transplantation. CONCLUSIONS: The prognosis of pediatric RCM is poor, and the heart transplantation rate is low in Japan.

Neutrophil degranulation biomarkers characterize restrictive echocardiographic pattern with diastolic dysfunction in patients with diabetes.

OBJECTIVE: To investigate the potential association between neutrophil degranulation and patterns of myocardial dysfunction in a cohort of patients with type 2 diabetes mellitus (T2DM). BACKGROUND: Two distinct phenotypes of diabetic cardiomyopathy have been described: a restrictive phenotype with diastolic dysfunction (restrictive/DD) and a dilative phenotype with systolic dysfunction (dilative/SD). However, the underlying determinants of these two patterns are not yet recognized. METHODS: In this single-centre, observational, cross-sectional study, 492 patients were recruited. Ultrasonographic measurements were performed by two experienced sonographers, blinded to the clinical data of the participants. Serum biomarkers of neutrophil degranulation were measured by enzyme-linked immunosorbent sandwich assay (ELISA). RESULTS: After adjustment for confounders, resistin, myeloperoxidase, matrix metalloproteinase 8 and matrix metalloproteinase 9/tissue inhibitor of metalloproteinases 1 complex were positively associated with the restrictive/DD pattern compared with the normal pattern. Similarly, MPO was positively associated with the dilative/SD pattern compared with the normal pattern, and resistin was negatively associated with the dilative/SD pattern compared with the restrictive/DD pattern. CONCLUSIONS: Neutrophil degranulation is associated with the restrictive/DD echocardiographic pattern in patients with T2DM, but not with the normal pattern and dilative/SD patterns. Neutrophils could have a pivotal role in the pathogenesis of myocardial dysfunction, and particularly diastolic dysfunction, in patients with T2DM.

Hereditary heart disease: pathophysiology, clinical presentation, and animal models of HCM, RCM, and DCM associated with mutations in cardiac myosin light chains.

Genetic cardiomyopathies, a group of cardiovascular disorders based on ventricular morphology and function, are among the leading causes of morbidity and mortality worldwide. Such genetically driven forms of hypertrophic (HCM), dilated (DCM), and restrictive (RCM) cardiomyopathies are chronic, debilitating diseases that result from biomechanical defects in cardiac muscle contraction and frequently progress to heart failure (HF). Locus and allelic heterogeneity, as well as clinical variability combined with genetic and phenotypic overlap between different cardiomyopathies, have challenged proper clinical prognosis and provided an incentive for identification of pathogenic variants. This review attempts to provide an overview of inherited cardiomyopathies with a focus on their genetic etiology in myosin regulatory (RLC) and essential (ELC) light chains, which are EF-hand protein family members with important structural and regulatory roles. From the clinical discovery of cardiomyopathy-linked light chain mutations in patients to an array of exploratory studies in animals, and reconstituted and recombinant systems, we have summarized the current state of knowledge on light chain mutations and how they induce physiological disease states via biochemical and biomechanical alterations at the molecular, tissue, and organ levels. Cardiac myosin RLC phosphorylation and the N-terminus ELC have been discussed as two important emerging modalities with important implications in the regulation of myosin motor function, and thus cardiac performance. A comprehensive understanding of such triggers is absolutely necessary for the development of target-specific rescue strategies to ameliorate or reverse the effects of myosin light chain-related inherited cardiomyopathies.

Endomyocardial Fibrosis: an Update After 70 Years.

PURPOSE OF REVIEW: This review aims at highlighting the need to better understand the pathogenesis and natural history of endomyocardial fibrosis when set against its changing endemicity and disease burden, improvements in diagnosis, and new options for clinical management. RECENT FINDINGS: Progress in imaging diagnostic techniques and availability of new targets for drug and surgical treatment of heart failure are contributing to earlier diagnosis and may lead to improvement in patient survival. Endomyocardial fibrosis was first described in Uganda by Davies more than 70 years ago (1948). Despite its poor prognosis, the etiology of this neglected tropical restrictive cardiomyopathy still remains enigmatic nowadays. Our review reflects on the journey of scientific discovery and construction of the current guiding concepts on this mysterious and fascinating condition, bringing to light the contemporary knowledge acquired over these years. Here we describe novel tools for diagnosis, give an overview of the improvement in clinical management, and finally, suggest research themes that can help improve patient outcomes focusing (whenever possible) on novel players coming into action.

Leukemic infiltration presenting as myocardial hypertrophy after complete remission of acute myeloid leukemia.

Here, we report a rare case of isolated leukemic infiltrate of the myocardium (extramedullary involvement) presenting as restrictive cardiomyopathy in a patient in complete remission of acute myeloid leukemia. It was evaluated with multimodality imaging studies (echocardiography and cardiac MRI) and further confirmed by pathology. The present case highlights the importance of maintaining a high degree of clinical suspicion when evaluating patients with progressive ventricular hypertrophy of unknown cause, including recognition of the potential involvement by recurrent hematologic malignancy.

Cardiac involvements in hypereosinophilia-associated syndrome: Case reports and a little review of the literature.

Hypereosinophilia-associated syndrome is a rare group of systemic diseases without certain underlying causes. Hypereosinophilic syndrome (HES) and eosinophilic granulomatosis with polyangiitis (EGPA), formerly known as Churg-Strauss syndrome (CSS), are initial considerations, when underlying causes remains unexplained despite of complete evaluation of hypereosinophilia. In this study, we report two rare cases, one case of HES with Loeffler endocarditis, and the other one of EGPA with restrictive cardiomyopathy mimicking myocardial infarction, to further address differential chief cardiac manifestations between HES and EGPA. Key roles of echocardiography played in detection of cardiac involvements, diagnosis, and prognosis prediction are also highlighted.

Heart Transplantation Outcomes in Radiation-Induced Restrictive Cardiomyopathy.

BACKGROUND: Some cancer therapies can cause advanced heart failure requiring heart transplantation. Although dilated cardiomyopathy is the most common phenotype, those who receive radiation may develop restrictive cardiomyopathy. The characteristics and transplantation outcomes patients with radiation-induced restrictive cardiomyopathy are not established. METHODS AND RESULTS: We used United Network for Organ Sharing registry to identify adults who were listed for heart transplantation between 2000 and 2015 for radiation-induced restrictive cardiomyopathy (RT-RCM) and compared their characteristics and transplant outcomes to restrictive cardiomyopathies of other etiologies (RCM) and all other patients listed for heart transplantation (others). Of 45,041 adults, 87 (0.2%) of transplantations were due to RT-RCM, 1049 (2.3%) were due to RCM, and there were 44,805 others. Compared with patients with RCM and other etiologies, those with RT-RCM were younger, less likely male, more likely to be white, listed as status 2, and were also more likely to have had previous cardiac surgeries. Posttransplant, patients with RT-RCM had longer lengths of stay and higher early mortality; 1-, 3-, and 5-year cumulative survival were as follows for RT-RCM (76%, 66%, 58%), RCM (88%, 79%, 73%; P = .025 compared with RT-RCM), and other etiologies (88%, 82%, 76%; P = .012 compared with RT-RCM). CONCLUSIONS: Patients with end-stage RT-RCM are predominantly younger females with previous cardiac surgeries. Posttransplantation survival in these patients appears to be lower than in those with other forms of restrictive cardiomyopathies and heart failure etiologies, mainly because of higher early postoperative mortality. Further studies are needed to confirm these findings.

A Challenging Differential Diagnosis: Distinguishing between Endomyocardial Fibrosis and Apical Hypertrophic Cardiomyopathy.

Endomyocardial fibrosis, which is a cause of restrictive cardiomyopathy, is characterized by the deposition of fibrous tissue in the apical region of 1 or both ventricles. The condition not only affects the diastolic dynamics of the ventricles, but also the function of the atrioventricular valves. The disease occurs predominantly in tropical regions worldwide and in sub-Saharan Africa. This condition is not well understood, with varied manifestations, from subclinical presentations to chronic and progressive edematous syndromes. Here, we present the challenging case of a patient with an indeterminate echocardiographic image, suggesting apical hypertrophy, plus severe aortic stenosis and fibrosis of the left ventricular outflow tract. An electrocardiogram revealed symmetrical T-wave inversion, which is a characteristic manifestation of apical hypertrophy. The importance of cardiac imaging examinations such as echocardiography and cardiac magnetic resonance for differentiating between endomyocardial fibrosis and apical hypertrophy is highlighted in this patient's case.

Clinical diabetic cardiomyopathy: a two-faced disease with restrictive and dilated phenotypes.

Diabetes mellitus-related cardiomyopathy (DMCMP) was originally described as a dilated phenotype with eccentric left ventricular (LV) remodelling and systolic LV dysfunction. Recently however, clinical studies on DMCMP mainly describe a restrictive phenotype with concentric LV remodelling and diastolic LV dysfunction. Both phenotypes are not successive stages of DMCMP but evolve independently to respectively heart failure with preserved left ventricular ejection fraction (HFPEF) or reduced left ventricular ejection fraction (HFREF). Phenotype-specific pathophysiological mechanisms were recently proposed for LV remodelling and dysfunction in HFPEF and HFREF consisting of coronary microvascular endothelial dysfunction in HFPEF and cardiomyocyte cell death in HFREF. A similar preferential involvement of endothelial or cardiomyocyte cell compartments explains DMCMP development into distinct restrictive/HFPEF or dilated/HFREF phenotypes. Diabetes mellitus (DM)-related metabolic derangements such as hyperglycaemia, lipotoxicity, and hyperinsulinaemia favour development of DMCMP with restrictive/HFPEF phenotype, which is more prevalent in obese type 2 DM patients. In contrast, autoimmunity predisposes to a dilated/HFREF phenotype, which manifests itself more in autoimmune-prone type 1 DM patients. Finally, coronary microvascular rarefaction and advanced glycation end-products deposition are relevant to both phenotypes. Diagnosis of DMCMP requires impaired glucose metabolism and exclusion of coronary, valvular, hypertensive, or congenital heart disease and of viral, toxic, familial, or infiltrative cardiomyopathy. In addition, diagnosis of DMCMP with restrictive/HFPEF phenotype requires normal systolic LV function and diastolic LV dysfunction, whereas diagnosis of DMCMP with dilated/HFREF phenotype requires systolic LV dysfunction. Treatment of DMCMP with restrictive/HFPEF phenotype is limited to diuretics and lifestyle modification, whereas DMCMP with dilated/HFREF phenotype is treated in accordance to HF guidelines.

Repeated radiofrequency ablation of atrial tachycardia in restrictive cardiomyopathy secondary to myofibrillar myopathy.

Myofibrillar myopathy is characterized by nonhyaline and hyaline lesions due to mutations in nuclear genes encoding for extra-myofibrillar or myofibrillar proteins. Cardiac involvement in myofibrillar myopathy may be phenotypically expressed as dilated, hypertrophic, or restrictive cardiomyopathy. Radiofrequency ablation of atrial fibrillation and flutter has so far not been reported in myofibrillar myopathy. We report the case of a young female with myofibrillar myopathy and deteriorating heart failure due to restrictive cardiomyopathy and recurrent atrial fibrillation and atrial tachycardias intolerant to pharmacotherapy. Cardiac arrhythmias were successfully treated with repeat radiofrequency ablations and resulted in regression of heart failure, thus postponing the necessity for cardiac transplantation.

Novel drugs targeting transthyretin amyloidosis.

Transthyretin amyloidosis (ATTR) is either a hereditary disease related to a mutation in the transthyretin gene that leads to neuropathy and/or cardiomyopathy or an acquired disease of the elderly that leads to restrictive cardiomyopathy. The prevalence of this disease is higher than once thought and awareness is likely to increase amongst physicians and in particular cardiologists. Until recently there have been no treatment options for this disease except to treat the heart failure with diuretics and the neuropathy symptomatically. However, there are several emerging pharmacologic therapies designed to slow or stop the progression of ATTR. This article reviews novel therapeutic drugs that work at different points in the pathogenesis of this disease attempting to change its natural history and improve outcomes.

Sudden death possibly related to lenalidomide given for cardiac and muscle AL amyloidosis secondary to light chain deposition disease.

OBJECTIVES: Restrictive cardiomyopathy due to AL amyloidosis has not been reported as the cause of sudden death. The risk of sudden death in AL amyloidosis may be further increased by potentially cardiotoxic medication, as in the following case. CASE REPORT: In a 69-year-old female, AL amyloidosis from light-chain deposition disease manifested as gastrointestinal pseudo-obstruction, restrictive cardiomyopathy, and secondary myopathy. AL amyloidosis was histologically confirmed by endomyocardial biopsy and muscle biopsy. One month after initiation of steroids and lenalidomide the patient suddenly died during sleep. It is speculated that sudden death was due to restrictive cardiomyopathy, cardiotoxicity of lenalidomide, pulmonary embolism, sudden unexplained death in epilepsy syndrome or stroke. The possible causes of sudden death are discussed. CONCLUSIONS: This case shows that AL amyloidosis from light-chain deposition disease may predominantly affect the intestines, myocardium and the skeletal muscle and that lenalidomide may have a beneficial effect on the amyloidosis but should be given with caution for its potential arrhythmogenic and thrombogenic side-effects.

[The donor's heart 22 years after the orthotopic transplantation].

The orthotopic heart transplantation is an acknowledge method for the treatment of cardiomyopathies of various etiology. Specific vasculopathy of the transplanted heart is considered to be a significant problem of the long-term postoperative period and serves the reason of low 10-years survival rates (not more then 50%). The issue unites the experience of follow-up and intravital electronic microscopy of transplantated heart's biopsies from 20 patients. Previously unknown data can help the clarification of posttransplantational cardiomyopathy.

A rare case of sudden death due to endomyocardial fibrosis in Italy: A differential diagnosis with other causes of restrictive cardiomyopathy.

A 45-years-old Indonesian woman was admitted to the hospital with nausea, vomiting, abdominal pain and tachyarrhythmia. Atrial fibrillation was found at ECG, blood tests showed mild hepatic function alterations. Radiological exams showed bilateral pleural effusions, ascites, hepatomegaly. Systolic and diastolic functions of the left ventricle were found to be strongly compromised at US. Physical conditions and laboratory results worsened rapidly, followed by multi organ failure. Death occurred 28 hours after admission. An autopsy was performed to clarify the cause of death and investigated medical malpractice. External examination showed jaundice skin and at internal examination bilateral pleural and pericardial effusions, ascites, mild cardiomegaly, ventricular endocardial fibrosis, a thrombus in tight junction to the left ventricular wall and hepatic necrosis were observed. Histological investigations revealed a massive endomyocardial fibrosis, detected through Azan-Mallory and Verhoef-Van-Gieson stain, and confirmed the presence of hepatic and renal necrosis. Toxicological and microbiological investigations were negative. The cause of death was a global cardiac dysfunction caused by a restrictive cardiomyopathy in an Indonesian woman affected by an undiagnosed and asymptomatic endomyocardial fibrosis. In this case, autopsy and histopathological investigations were fundamental to diagnose an occult endomyocardial fibrosis, which is an idiopathic disorder of tropical and subtropical regions of the world. The not common incidence of this disease in our country and its unusual clinical onset were at first perceived as a medical malpractice from the relatives. Consequently, the clinical aspects of the case intertwine with the medicolegal implications concerning the undiagnosed disease and the causality with the patient's death.

Right ventricular endomyocardial fibrosis.

Endomyocardial fibrosis is a variety of restrictive cardiomyopathy, in which endocardium of one or both ventricles is thickened markedly with involvement of underlying myocardium. Partial obliteration of ventricular cavities by fibrous tissue and thrombus causes diastolic dysfunction with increased resistance to ventricular filling. Systolic function is well preserved till late stages. Biventricular or isolated left ventricular involvement is common. Isolated right ventricular involvement is relatively uncommon. Case reports on endomyocardial fibrosis have declined in literature. In India, endomyocardial fibrosis is mainly reported from Kerala. A case of right ventricular endomyocardial fibrosis from West Bengal is reported here. Isolated right sided endomyocardial fibrosis, massive right atrial enlargement, complete disorganization of tricuspid valve, massive pericardial effusion, normal absolute eosinophil count and its sporadic occurrence outside 15 degrees of the equatorial belt were interesting features in this case of endomyocardial fibrosis. X-ray features were typical of pericardial effusion masking underlying endomyocardial fibrosis. Endomyocardial fibrosis is a neglected research field. It needs more attention from biomedical researchers.

Diabetes, oxidative stress, molecular mechanism, and cardiovascular disease--an overview.

In recent years, diabetes and its associated complications have come to represent a major public health concern. It is a complex disease characterized by multiple metabolic derangements and is known to impair cardiac function by disrupting the balance between pro-oxidants and antioxidants at the cellular level. The subsequent generation of reactive oxygen species (ROS) and accompanying oxidative stress are hallmarks of the molecular mechanisms responsible for cardiovascular disease. Among several oxidative stress-mediated mechanisms that have been proposed, ROS-mediated oxidative stress has received the most attention. ROS have been shown to interact with proteins, lipids, and DNA, causing damage to the cellular macromolecules and subsequently, deterioration of cellular function. Induction of thioredoxin-1 (Trx1) gene expression has been demonstrated to protect the diabetic myocardium from dysfunction by reducing oxidative stress and enhancing the expression of heme oxygenase-1 (HO-1) and vascular endothelial growth factor (VEGF). The failure of antioxidants to consistently demonstrate clinical benefit necessitates further investigation of the role of oxidative stress in diabetes-mediated cardiovascular disease.

Overview of Restrictive Cardiomyopathies.

Restrictive cardiomyopathy (RCM) includes a heterogeneous group of diseases that cause increased myocardial stiffness, leading to impaired ventricular relaxation and severe diastolic dysfunction. Given that it is the least common type of cardiomyopathy, it can be a diagnostic challenge due to its varied pathogenesis, clinical presentation, and diagnostic evaluation. In this review, we provide an overview of different etiologies of RCM and examine the diagnostic and treatment approaches for various types.