Restrictive cardiomyopathy

Long-term prognostic value of big endothelin-1 and its combination with late gadolinium enhancement in patients with idiopathic restrictive cardiomyopathy

BACKGROUND AND AIMS

Idiopathic restrictive cardiomyopathy (RCM) has a low incidence. This study aimed to determine the prognostic value of big endothelin-1 (ET-1) in idiopathic RCM.

MATERIALS AND METHODS

We prospectively enrolled patients with idiopathic RCM from 2009 to 2017 and followed them up. The primary outcome was a composite of all-cause mortality and cardiac transplantation, and the secondary outcome was a composite of cardiac death and cardiac transplantation.

RESULTS

Ninety-one patients were divided into the high big ET-1 (>0.85 pmol/L, n = 56) and low big ET-1 (≤0.85 pmol/L, n = 35) groups, and 87 of them completed the follow-up. Big ET-1 concentrations (hazard ratio: 1.756, 95 % confidence interval [CI]: 1.117-2.760) and late gadolinium enhancement (LGE) (hazard ratio: 3.851, 95 % CI: 1.238-11.981) were independent risk factors for the primary outcome. Big ET-1 concentrations (C-statistic estimation: 0.764, 95 % CI: 0.657-0.871) and the combination of LGE and big ET-1 concentrations (C-statistic estimation: 0.870, 95 % CI: 0.769-0.970) could accurately predict the 5-year transplant-free survival rate, and 0.85 pmol/L was a suitable cutoff for big ET-1.

CONCLUSION

Big ET-1 and its combination with LGE may be useful to predict an adverse prognosis in patients with idiopathic RCM.

Growth and endocrinopathies among children with β-Thalassemia major treated at Dubai Thalassemia centre

BACKGROUND

β-Thalassemia major (BTM) is one of the most common hereditary anemias worldwide. Patients suffer from iron overload that results from repeated blood transfusion This in turn leads to multiple organ damage and endocrinopathies. This study aims to assess the prevalence of growth retardation, hypothyroidism, and diabetes mellitus in children and adolescents with BTM treated at Dubai Thalassemia Centre.

METHODS

A total of 105 children and adolescents were included in this retrospective observational study.

RESULTS

39 children and 66 adolescents' data were analyzed. Females composed 51.3% (n = 20) of children and 53.0% (n = 35) of adolescents. Pretransfusion hemoglobin below 9 gm/dl was observed in 10.8% (n = 4) and 10.6% (n = 7) in children and adolescents, respectively. The mean age of menarche was 13.5 years. Among all study participants, 22.6% (n = 14) had normal height velocity whereas 37.1% (n = 23) had reduced height velocity in one year and 40.3% (n = 25) had reduced height velocity in two consecutive years. The proportion of children and adolescents showing reduced height velocity was significantly higher in females compared to the males (90.6% versus 63.3%, respectively, Chi-square = 6.597, p-value = 0.010). Although none of the study participants had diabetes mellitus, 26.1% (n = 12/46) had pre-diabetes. Elevated TSH was observed in 14.7% (n = 5) children and 8.1% (n = 5) adolescents while low FT4 was reported in one child and one adolescent.

CONCLUSION

Of all endocrinopathies seen among children and adolescents with BTM, growth delay remains the main concern for this group of patients. Effective treatment is key to further reducing endocrinopathies. Although the sample size is limited, we postulate that the low percentage of endocrinopathies among children with BTM treated at Dubai thalassemia center and the low level of pretransfusion anemia reflect the effective transfusion and chelation at the center.

Multimodality Imaging in Differentiating Constrictive Pericarditis From Restrictive Cardiomyopathy: A Comprehensive Overview for Clinicians and Imagers

In the evaluation of heart failure, 2 differential diagnostic considerations include constrictive pericarditis and restrictive cardiomyopathy. The often outwardly similar clinical presentation of these 2 pathologic entities routinely renders their clinical distinction difficult. Consequently, initial assessment requires a keen understanding of their separate pathophysiology, epidemiology, and hemodynamic effects. Following a detailed clinical evaluation, further assessment initially rests on comprehensive echocardiographic investigation, including detailed Doppler evaluation. With the combination of mitral inflow characterization, tissue Doppler assessment, and hepatic vein interrogation, initial differentiation of constrictive pericarditis and restrictive cardiomyopathy is often possible with high sensitivity and specificity. In conjunction with a compatible clinical presentation, successful differentiation enables both an accurate diagnosis and subsequent targeted management. In certain cases, however, the diagnosis remains unclear despite echocardiographic assessment, and additional evaluation is required. With advances in noninvasive tools, such evaluation can often continue in a stepwise, algorithmic fashion noninvasively, including both cross-sectional and nuclear imaging. Should this additional evaluation itself prove insufficient, invasive assessment with appropriate expertise may ultimately be necessary.

Cardiovascular Manifestations of Hemochromatosis: A Review of Pathophysiology, Mechanisms, and Treatment Options

Hemochromatosis is a genetic disorder characterized by excessive absorption and accumulation of iron in the body. It is one of the most common inherited disorders. The excess iron deposition can cause damage to various organs, including the liver, heart, pancreas, and joints. If left untreated, hemochromatosis can lead to serious complications such as cirrhosis, diabetes, heart failure, and increased risk of certain cancers. Iron overload in hemochromatosis significantly affects the cardiovascular system, leading to morbidity and mortality. This article reviews the current literature describing the pathogenesis and various cardiovascular manifestations of hemochromatosis, including dilated cardiomyopathy, conduction abnormalities, heart failure, cardiac fibrosis, myocardial infarction, and valvular heart disease. This article aims to provide a detailed understanding of the cardiovascular manifestations associated with hemochromatosis and their underlying mechanisms through a review of current literature in publicly available databases.

Amyloidosis of the Heart: A Comprehensive Review

Cardiac amyloidosis is a progressive, infiltrative cardiomyopathy, whose types are based on various infiltrating amyloids, namely, light chains in primary amyloidosis, mutated transthyretin proteins in hereditary amyloidosis, and wild-type transthyretin proteins in senile amyloidosis. While cardiac amyloidosis has a non-specific presentation, the type-specific presentations may provide some clues to the diagnosis. While tissue biopsy remains the gold standard, other newer non-invasive methods can aid in the diagnostic approach for suspected cardiac amyloidosis. Various medications used to treat heart failure may lead to adverse outcomes in patients with cardiac amyloidosis. More research is needed to understand the adequate management and treatment of cardiac amyloidosis.

Endomyocardial fibrosis related sudden cardiac death; two autopsied case-reports from Egypt

Endomyocardial fibrosis (EMF) is an idiopathic tropical disorder that is characterized by the development of restrictive cardiomyopathy. Neglected EMF can cause sudden cardiac death (SCD) in adults. Conclusive diagnosis of EMF depends on autopsy after death. In an effort to attract the interest of the community for this rare disease, we report two cases of SCD that were diagnosed as EMF during autopsy in Egypt. Both cases were thoroughly investigated with emphasis on death circumstances and post-mortem anatomical and histopathological findings. The two cases were for adult males presented with SCD following a quarrel with a negative medical history and family history regarding cardiac diseases. No trauma or drug abuse. The autopsy revealed hypertrophied hearts, thick fibrosed endocardium, patchy myocardial fibrosis, and filling of the apex by fibrosis and calcifications. In one of them, there was a huge mural thrombus reaching the level of the mitral valve that totally occluded the cavity of the left ventricle. Histopathologically, fibrosis was confirmed, and no eosinophils were detected. In contrast to previously reported cases in Egypt, the left ventricle was solely affected. Despite the rarity of the disease outside the tropics, the frequency of EMF cases is more likely to be more than the number of reported cases. EMF should be considered as possible cause of SCD during autopsy. Further studies are needed to clarify the etiology and epidemiology of EMF.

Prevalence and Impact of Arrhythmia on Outcomes in Restrictive Cardiomyopathy-A Report from the Beijing Municipal Health Commission Information Center (BMHCIC) Database

BACKGROUND

Data on the outcomes of restrictive cardiomyopathy (RCM) are limited, when the condition is complicated with arrhythmia. This study was designed to investigate the prevalence of atrial fibrillation (AF), ventricular tachycardia (VT) and bradycardia (BC) and their impact on adverse outcomes (intra-cardiac thrombus, stroke and systematic embolism [SSE], heart failure and death) of RCM.

METHODS AND RESULTS

The retrospective cohort study used data collected from the Beijing Municipal Health Commission Information Center (BMHCIC) database from 1 January 2010 to 31 December 2020. There were 745 (64.9%) patients with AF, 117 (10.2%) patients with VT and 311 (27.1%) patients with bradycardia. The presence of AF was associated with an increased risk of SSE (adjusted HR:1.37, 95%CI:1.02-1.83, p = 0.04) and heart failure (aHR:1.36, 95%CI:1.17-1.58, p < 0.001). VT was associated with an increased risk of intracardiac thrombus (aHR:2.34, 95%CI:1.36-4.01, p = 0.002) and death (aHR:2.07, 95%CI:1.19-3.59, p = 0.01). Bradycardia did not increase the adverse outcomes in RCM. The results remained consistent and steady when AF, VT and bradycardia were adjusted as competing factors.

CONCLUSIONS

Cardiac arrhythmia are highly prevalent and associated with adverse outcomes in patients with RCM. AF and VT are more likely to be associated with intracardiac thrombosis, and the presence of AF increased the risk of SSE and HF. The presence of VT increased the risk of death.

Arrhythmias and Heart Failure in Pregnancy: A Dialogue on Multidisciplinary Collaboration

The prevalence of CVD in pregnant people is estimated to be around 1 to 4%, and it is imperative that clinicians that care for obstetric patients can promptly and accurately diagnose and manage common cardiovascular conditions as well as understand when to promptly refer to a high-risk obstetrics team for a multidisciplinary approach for managing more complex patients. In pregnant patients with CVD, arrhythmias and heart failure (HF) are the most common complications that arise. The difficulty in the management of these patients arises from variable degrees of severity of both arrhythmia and heart failure presentation. For example, arrhythmia-based complications in pregnancy can range from isolated premature ventricular contractions to life-threatening arrhythmias such as sustained ventricular tachycardia. HF also has variable manifestations in pregnant patients ranging from mild left ventricular impairment to patients with advanced heart failure with acute decompensated HF. In high-risk patients, a collaboration between the general obstetrics, maternal-fetal medicine, and cardiovascular teams (which may include cardio-obstetrics, electrophysiology, adult congenital, or advanced HF)—physicians, nurses and allied professionals—can provide the multidisciplinary approach necessary to properly risk-stratify these women and provide appropriate management to improve outcomes.

Mechanical and interventional support for heart failure with preserved ejection fraction: A review

INTRODUCTION

Restrictive cardiomyopathy (RCM) and hypertrophic cardiomyopathy (HCM) are two disease processes that are known to progress to heart failure with preserved ejection fraction (HFpEF). Pharmacologic therapies for HFpEF have not improved patient outcomes or reduced mortality in this patient cohort; thus, there continues to be substantial interest in other treatment strategies, including surgical interventions and devices. In this article, we explore and report the current utility of percutaneous therapies and surgically implanted mechanical support in the treatment of patients with HFpEF.

RESULTS

Treatment strategies include percutaneous interventions with interatrial shunts, left atrial assist devices (LAADs), and ventricular assist devices (VADs) in various configurations. Although VADs have been employed to treat patients with heart failure with reduced ejection fraction, their efficacy is limited in those with RCM and HCM. A left atrial-to-aortic VAD has been proposed to directly unload the left atrium, but data is limited. Alternatively, a LAAD could be placed in the mitral position and simultaneously unload the left atrium, while filling the left ventricle.

CONCLUSION

A left atrial assist device in the mitral position is a promising solution to address the hemodynamic abnormalities in RCM and HCM; these pumps, however, are still under development.

Mixed-Etiology Restrictive Cardiomyopathy (Desminopathy and Hemochromatosis) with Complex Liver Lesions

A 28 year-old male with restrictive cardiomyopathy (RCM) and endocardium thickening, conduction disorders, heart failure, and depressive disorder treated with paroxetine was admitted to the clinic. Blood tests revealed an increase in serum iron level, transferrin saturation percentage, and slightly elevated liver function tests. Sarcoidosis, storage diseases and Loeffler endocarditis were ruled out. Mutations in desmin (DES) and hemochromatosis gene (HFE1) were identified. Liver biopsy was obtained to verify the hemochromatosis, assess its possible contribution to the RCM progression and determine indications for treatment. Biopsy revealed signs of drug-induced injury, subcompensated heart failure, and hemosiderin accumulation. Thus, even if one obvious cause (desmin mutation) of RCM has been identified, other less likely causes should be taken into consideration.

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.

A novel Troponin I mutation associated with severe restrictive cardiomyopathy-a case report of a 27-year-old woman with fatigue

BACKGROUND

Restrictive cardiomyopathy is rare and heterogeneous in origin, clinical manifestation, and prognosis. Familial forms have, amongst others, been associated with mutations in the TNNI3 gene. We present a case of familial restrictive cardiomyopathy associated with a novel TNNI3 mutation including longitudinal follow-up.

CASE SUMMARY

A 27-year-old woman was evaluated for fatigue in the context of a family history of sudden cardiac death. Echocardiography was normal except for mild left atrial dilatation. Focused genetic screening, limited to the most common genes associated with cardiomyopathy, was unremarkable in 2006. In biopsy, mild inflammatory cardiomyopathy was diagnosed, and the patient was discharged. Thirteen years later, rapid clinical deterioration occurred in the context of new-onset atrial fibrillation (AF). Echocardiography now showed gross bi-atrial dilatation and evidence of diastolic dysfunction. Based on haemodynamic tracings during angiography, a diagnosis of restrictive cardiomyopathy was made. In 2018, next-generation sequencing revealed the hitherto undescribed Troponin I variant Lys193Glu in a functionally critical domain. Haemodynamic stabilization was achieved by pulmonary vein isolation. Until now, the patient remains symptom free under diuretic treatment.

DISCUSSION

Diagnosis of restrictive cardiomyopathy is complicated by often oligosymptomatic early presentation and a diverse clinical picture. Thorough medical and family history and early invasive haemodynamic tracing are indispensable in diagnosis. Therapy-refractory AF should raise suspicion. Reporting of longitudinal follow-up cases is essential to better understand the early symptoms, development, and prognosis of this rare disease. Broad genetic testing in unclear cases has become more available and affordable and should be considered early in the diagnostic workflow.

Systematic identification of ACE2 expression modulators reveals cardiomyopathy as a risk factor for mortality in COVID-19 patients

BACKGROUND

Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for SARS-CoV-2. It plays critical roles in both the transmission and the pathogenesis of COVID-19. Comprehensive profiling of ACE2 expression patterns could reveal risk factors of severe COVID-19 illness. While the expression of ACE2 in healthy human tissues has been well characterized, it is not known which diseases and drugs might be associated with ACE2 expression.

RESULTS

We develop GENEVA (GENe Expression Variance Analysis), a semi-automated framework for exploring massive amounts of RNA-seq datasets. We apply GENEVA to 286,650 publicly available RNA-seq samples to identify any previously studied experimental conditions that could be directly or indirectly associated with ACE2 expression. We identify multiple drugs, genetic perturbations, and diseases that are associated with the expression of ACE2, including cardiomyopathy, HNF1A overexpression, and drug treatments with RAD140 and itraconazole. Our joint analysis of seven datasets confirms ACE2 upregulation in all cardiomyopathy categories. Using electronic health records data from 3936 COVID-19 patients, we demonstrate that patients with pre-existing cardiomyopathy have an increased mortality risk than age-matched patients with other cardiovascular conditions. GENEVA is applicable to any genes of interest and is freely accessible at http://genevatool.org .

CONCLUSIONS

This study identifies multiple diseases and drugs that are associated with the expression of ACE2. The effect of these conditions should be carefully studied in COVID-19 patients. In particular, our analysis identifies cardiomyopathy patients as a high-risk group, with increased ACE2 expression in the heart and increased mortality after SARS-COV-2 infection.

Targeted therapies in genetic dilated and hypertrophic cardiomyopathies: From molecular mechanisms to therapeutic targets

Genetic cardiomyopathies are disorders of the cardiac muscle, most often explained by pathogenic mutations in genes encoding sarcomere, cytoskeleton, or ion channel proteins. Clinical phenotypes such as heart failure and arrhythmia are classically treated with generic drugs, but aetiology‐specific and targeted treatments are lacking. As a result, cardiomyopathies still present a major burden to society, and affect many young and older patients. The Translational Committee of the Heart Failure Association (HFA) and the Working Group of Myocardial Function of the European Society of Cardiology (ESC) organized a workshop to discuss recent advances in molecular and physiological studies of various forms of cardiomyopathies. The study of cardiomyopathies has intensified after several new study setups became available, such as induced pluripotent stem cells, three‐dimensional printing of cells, use of scaffolds and engineered heart tissue, with convincing human validation studies. Furthermore, our knowledge on the consequences of mutated proteins has deepened, with relevance for cellular homeostasis, protein quality control and toxicity, often specific to particular cardiomyopathies, with precise effects explaining the aberrations. This has opened up new avenues to treat cardiomyopathies, using contemporary techniques from the molecular toolbox, such as gene editing and repair using CRISPR‐Cas9 techniques, antisense therapies, novel designer drugs, and RNA therapies. In this article, we discuss the connection between biology and diverse clinical presentation, as well as promising new medications and therapeutic avenues, which may be instrumental to come to precision medicine of genetic cardiomyopathies.

Naive Bayes Prediction of the Development of Cardiac Events in Heart Failure With Preserved Ejection Fraction in an Outpatient Clinic - Beyond B-Type Natriuretic Peptide

BACKGROUND

The heterogeneity of B-type natriuretic peptide (BNP) levels among individuals with heart failure and preserved ejection fraction (HFpEF) makes predicting the development of cardiac events difficult. This study aimed at creating high-performance Naive Bayes (NB) classifiers, beyond BNP, to predict the development of cardiac events over a 3-year period in individual outpatients with HFpEF.Methods and Results:We retrospectively enrolled 234 outpatients with HFpEF who were followed up for 3 years. Parameters with a coefficient of association ≥0.1 for cardiac events were applied as features of classifiers. We used the step forward method to find a high-performance model with the maximum area under the receiver operating characteristics curve (AUC). A 10-fold cross-validation method was used to validate the generalization performance of the classifiers. The mean kappa statistics, AUC, sensitivity, specificity, and accuracy were evaluated and compared between classifiers learning multiple factors and only the BNP. Kappa statistics, AUC, and sensitivity were significantly higher for NB classifiers learning 13 features than for those learning only BNP (0.69±0.14 vs. 0.54±0.12 P=0.024, 0.94±0.03 vs. 0.84±0.05 P<0.001, 85±8% vs. 64±20% P=0.006, respectively). The specificity and accuracy were similar.

CONCLUSIONS

We created high-performance NB classifiers for predicting the development of cardiac events in individual outpatients with HFpEF. Our NB classifiers may be useful for providing precision medicine for these patients.

The Impact of Deep Y Descent on Hemodynamics in Patients With Heart Failure and Preserved Left Ventricular Systolic Function

Background: Influence of right ventricular diastolic function on the hemodynamics of heart failure (HF). We aimed to clarify the hemodynamic features of deep Y descent in the right atrial pressure waveform in patients with HF and preserved left ventricular systolic function.

Methods: In total, 114 consecutive inpatients with HF who had preserved left ventricular systolic function (left ventricular ejection fraction ≥ 50%) and right heart catheterization were retrospectively enrolled in this study. The patients were divided into two groups according to right atrial pressure waveform, and those with Y descent deeper than X descent in the right atrial pressure waveform were assigned to the deep Y descent group. We enrolled another seven patients (two men, five women; mean age, 87 ± 6) with HF and preserved ejection fraction, and implanted a pacemaker to validate the results of this study.

Results: The patients with deep Y descent had a higher rate of atrial fibrillation, higher right atrial pressure and mean pulmonary arterial pressure, and lower stroke volume and cardiac index than those with normal Y descent (76 vs. 7% p < 0.001, median 8 vs. 5 mmHg p = 0.001, median 24 vs. 21 mmHg p = 0.036, median 33 vs. 43 ml/m²p < 0.001, median 2.2 vs. 2.7 L/m², p < 0.001). Multiple linear regression revealed a negative correlation between stroke volume index and pulmonary vascular resistance index (wood unit*m²) only in the patients with deep Y descent (estimated regression coefficient: −1.281, p = 0.022). A positive correlation was also observed between cardiac index and heart rate in this group (r = 0.321, p = 0.038). In the other seven patients, increasing the heart rate (from median 60 to 80/min, p = 0.001) significantly reduced the level of BNP (from median 419 to 335 pg/ml, p = 0.005).

Conclusions: The hemodynamics of patients with HF with deep Y descent and preserved left ventricular systolic function resembled right ventricular restrictive physiology. Optimizing the heart rate may improve hemodynamics in these patients.

Anticoagulation in cardiomyopathy: unravelling the hidden threat and challenging the threat individually

Cardiomyopathy comprises a heterogeneous group of myocardial abnormalities, structural or functional in nature, in the absence of coronary artery disease and other abnormal loading conditions. These myocardial pathologies can result in premature death or disability from progressive heart failure, arrhythmia, stroke, or other embolic events. The European Cardiomyopathy Registry reports a high stroke risk in cardiomyopathy patients ranging from 2.1% to 4.5%, as well as high prevalence of atrial fibrillation ranging from 14.0% to 48.5%. There is a growing interest in evaluating the risk of thromboembolism depending on the type of cardiomyopathy, as well as if anticoagulation is indicated in patients with cardiomyopathy without atrial fibrillation. Data available do not unequivocally support anticoagulation therapy in all of these patients; the management of these patients remains challenging. Many published reports pertaining to the risk of thromboembolism and consecutive treatment strategies mainly focus on single cardiomyopathy subtype. We summarize essential pathophysiological knowledge and review current literature associated with thromboembolism in various cardiomyopathy subtypes, providing recommendations for the diagnostic evaluation as well as clinical management strategies in this field. Certain cardiomyopathy subtypes require anticoagulation independent of atrial fibrillation or CHA2 DS2 -VASc score. Despite the scarcity of evidence regarding the choice of anticoagulation regimen (vitamin K antagonist vs. non-vitamin K oral anticoagulants) in cardiomyopathy, it is discussed and reviewed in this article. Each patient should receive a tailored strategy based on thorough clinical evaluation, published evidence, and clinical experience, due to the current recommendations mostly developed on small-sample studies or empirical evidence. The future research priorities in this area are also addressed in this article.

The Feline Cardiomyopathies: 3. Cardiomyopathies other than HCM

Practical relevance:

Although feline hypertrophic cardiomyopathy (HCM) occurs more commonly, dilated cardiomyopathy (DCM), restrictive cardiomyopathy (RCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), left ventricular noncompaction (LVNC) and cardiomyopathy – nonspecific phenotype (NCM; formerly unclassified cardiomyopathy) are all recognized in domestic cats.

Patient group:

Any adult domestic cat, of either sex and of any breed, can be affected.

Diagnostics:

The non-HCM cardiomyopathies are rarely suspected in subclinically affected cats, so most are first identified when a cat presents with signs of heart failure or systemic thromboembolic disease. The definitive clinical confirmatory test for these other feline cardiomyopathies is echocardiography.

Key findings:

‘Cardiomyopathy – nonspecific phenotype’ is a catch-all term that groups hearts with myocardial changes that either do not meet the criteria for any one type of cardiomyopathy (HCM, RCM, DCM, ARVC, LVNC) or meet the echocardiography criteria for more than one type. RCM is characterized by diastolic dysfunction due to fibrosis that results in a restrictive transmitral flow pattern on Doppler echocardiography and usually marked left or biatrial enlargement. DCM is characterized by decreased myocardial contractility and is rare in cats. When it occurs, it is seldom due to taurine deficiency. However, since taurine-deficient DCM is usually reversible, a diet history should be obtained, whole blood and plasma taurine levels should be measured and taurine should be supplemented in the diet if the diet is not commercially manufactured. ARVC should be suspected in adult cats with severe right heart enlargement and right heart failure (ascites and/or pleural effusion), especially if arrhythmia is present. Feline LVNC is rare; its significance continues to be explored. Treatment of the consequences of these cardiomyopathies (management of heart failure, thromboprophylaxis, treatment of systemic arterial thromboembolism) is the same as for HCM.

Conclusions:

While these other cardiomyopathies are less prevalent than HCM in cats, their clinical and radiographic presentation is often indistinguishable from HCM. Echocardiography is usually the only ante-mortem method to determine which type of cardiomyopathy is present. However, since treatment and prognosis are often similar for the feline cardiomyopathies, distinguishing among the cardiomyopathies is often not essential for determining appropriate therapy.

Areas of uncertainty:

The feline cardiomyopathies do not always fit into one distinct category. Interrelationships among cardiomyopathies in cats may exist and understanding these relationships in the future might provide critical insights regarding treatment and prognosis.

Cardiac Amyloidosis Presenting with Pre-Excitation Syndrome, Heart Failure, and Severe Factor X Deficiency as Part of Systemic Amyloid Light-Chain (AL) Amyloidosis - A Fatal Combination

Patient: Male, 37-year-old

Final Diagnosis: Cardiac amyloidosis

Symptoms: Palpitation • syncope

Medication: —

Clinical Procedure: —

Specialty: Cardiology • Hematology

Cardiomyopathies: An Overview

Background: Cardiomyopathies are a heterogeneous group of pathologies characterized by structural and functional alterations of the heart. Aims: The purpose of this narrative review is to focus on the most important cardiomyopathies and their epidemiology, diagnosis, and management. Methods: Clinical trials were identified by Pubmed until 30 March 2021. The search keywords were “cardiomyopathies, sudden cardiac arrest, dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy, arrhythmogenic cardiomyopathy (ARCV), takotsubo syndrome”. Results: Hypertrophic cardiomyopathy (HCM) is the most common primary cardiomyopathy, with a prevalence of 1:500 persons. Dilated cardiomyopathy (DCM) has a prevalence of 1:2500 and is the leading indication for heart transplantation. Restrictive cardiomyopathy (RCM) is the least common of the major cardiomyopathies, representing 2% to 5% of cases. Arrhythmogenic cardiomyopathy (ARCV) is a pathology characterized by the substitution of the myocardium by fibrofatty tissue. Takotsubo cardiomyopathy is defined as an abrupt onset of left ventricular dysfunction in response to severe emotional or physiologic stress. Conclusion: In particular, it has been reported that HCM is the most important cause of sudden death on the athletic field in the United States. It is needless to say how important it is to know which changes in the heart due to physical activity are normal, and when they are pathological.

Effect of a reduced donor heart right ventricular distensibility on post-heart transplant haemodynamics

OBJECTIVES

This study aimed to investigate the characteristics of a reduced right ventricular distensibility after heart transplant.

METHODS

This study enrolled 64 adult patients who underwent heart transplant at our institution. The degree of right ventricular distensibility was quantified by calculating the difference between right atrial pressures (RAPs) of X descent and Y descent (X-Y) from the RAP waveform in right heart catheterization. Histologically, the ratio of the interstitial tissue in myocardial biopsy samples was calculated.

RESULTS

Of the 64 patients, 35 (55%) had a reduced right ventricular distensibility at 1 week after heart transplant (X-Y > 1 mmHg, RD group), and 29 (45%) had a normal right ventricular distensibility (X-Y ≤ 1 mmHg, ND group). The mean RAP and mean pulmonary capillary wedge pressure 1 week after heart transplant in the RD group were significantly higher than that in the ND group. The mean RAP and mean pulmonary capillary wedge pressure in the RD group gradually normalized 12 weeks postoperation. The ratio of the interstitial tissue of biopsy samples significantly correlated with the X-Y value. The number of patients who required inotropic support >14 days was higher in the RD group than in the ND group.

CONCLUSIONS

Reduced donor heart distensibility was a common impairment early after heart transplant. It might result from interstitial oedema in the myocardial tissue of the donor heart. Reduced donor heart distensibility after heart transplant might be associated with early clinical outcomes; however, further investigation is required.

Overexpression of human BAG3P209L in mice causes restrictive cardiomyopathy

An amino acid exchange (P209L) in the HSPB8 binding site of the human co-chaperone BAG3 gives rise to severe childhood cardiomyopathy. To phenocopy the disease in mice and gain insight into its mechanisms, we generated humanized transgenic mouse models. Expression of human BAG3^P209L-eGFP in mice caused Z-disc disintegration and formation of protein aggregates. This was accompanied by massive fibrosis resulting in early-onset restrictive cardiomyopathy with increased mortality as observed in patients. RNA-Seq and proteomics revealed changes in the protein quality control system and increased autophagy in hearts from hBAG3^P209L-eGFP mice. The mutation renders hBAG3^P209L less soluble in vivo and induces protein aggregation, but does not abrogate hBAG3 binding properties. In conclusion, we report a mouse model mimicking the human disease. Our data suggest that the disease mechanism is due to accumulation of hBAG3^P209L and mouse Bag3, causing sequestering of components of the protein quality control system and autophagy machinery leading to sarcomere disruption.

An amino acid exchange (P209L) in the human co-chaperone BAG3 gives rise to severe childhood restrictive cardiomyopathy. Here the authors describe humanized transgenic mouse models which phenocopy the disease and provide insight into the pathogenic mechanisms.

Cardiomyopathic mutations in essential light chain reveal mechanisms regulating the super relaxed state of myosin

In this study, we assessed the super relaxed (SRX) state of myosin and sarcomeric protein phosphorylation in two pathological models of cardiomyopathy and in a near-physiological model of cardiac hypertrophy. The cardiomyopathy models differ in disease progression and severity and express the hypertrophic (HCM-A57G) or restrictive (RCM-E143K) mutations in the human ventricular myosin essential light chain (ELC), which is encoded by the MYL3 gene. Their effects were compared with near-physiological heart remodeling, represented by the N-terminally truncated ELC (Δ43 ELC mice), and with nonmutated human ventricular WT-ELC mice. The HCM-A57G and RCM-E143K mutations had antagonistic effects on the ATP-dependent myosin energetic states, with HCM-A57G cross-bridges fostering the disordered relaxed (DRX) state and the RCM-E143K model favoring the energy-conserving SRX state. The HCM-A57G model promoted the switch from the SRX to DRX state and showed an ∼40% increase in myosin regulatory light chain (RLC) phosphorylation compared with the RLC of normal WT-ELC myocardium. On the contrary, the RCM-E143K–associated stabilization of the SRX state was accompanied by an approximately twofold lower level of myosin RLC phosphorylation compared with the RLC of WT-ELC. Upregulation of RLC phosphorylation was also observed in Δ43 versus WT-ELC hearts, and the Δ43 myosin favored the energy-saving SRX conformation. The two disease variants also differently affected the duration of force transients, with shorter (HCM-A57G) or longer (RCM-E143K) transients measured in electrically stimulated papillary muscles from these pathological models, while no changes were displayed by Δ43 fibers. We propose that the N terminus of ELC (N-ELC), which is missing in the hearts of Δ43 mice, works as an energetic switch promoting the SRX-to-DRX transition and contributing to the regulation of myosin RLC phosphorylation in full-length ELC mice by facilitating or sterically blocking RLC phosphorylation in HCM-A57G and RCM-E143K hearts, respectively.

Hypertrophic Cardiomyopathy and Primary Restrictive Cardiomyopathy: Similarities, Differences and Phenocopies

Hypertrophic cardiomyopathy (HCM) and primary restrictive cardiomyopathy (RCM) have a similar genetic background as they are both caused mainly by variants in sarcomeric genes. These “sarcomeric cardiomyopathies” also share diastolic dysfunction as the prevalent pathophysiological mechanism. Starting from the observation that patients with HCM and primary RCM may coexist in the same family, a characteristic pathophysiological profile of HCM with restrictive physiology has been recently described and supports the hypothesis that familiar forms of primary RCM may represent a part of the phenotypic spectrum of HCM rather than a different genetic cardiomyopathy. To further complicate this scenario some infiltrative (amyloidosis) and storage diseases (Fabry disease and glycogen storage diseases) may show either a hypertrophic or restrictive phenotype according to left ventricular wall thickness and filling pattern. Establishing a correct etiological diagnosis among HCM, primary RCM, and hypertrophic or restrictive phenocopies is of paramount importance for cascade family screening and therapy.

YAP plays a crucial role in the development of cardiomyopathy in lysosomal storage diseases

Lysosomal dysfunction caused by mutations in lysosomal genes results in lysosomal storage disorder (LSD), characterized by accumulation of damaged proteins and organelles in cells and functional abnormalities in major organs, including the heart, skeletal muscle, and liver. In LSD, autophagy is inhibited at the lysosomal degradation step and accumulation of autophagosomes is observed. Enlargement of the left ventricle (LV) and contractile dysfunction were observed in RagA/B cardiac-specific KO (cKO) mice, a mouse model of LSD in which lysosomal acidification is impaired irreversibly. YAP, a downstream effector of the Hippo pathway, was accumulated in RagA/B cKO mouse hearts. Inhibition of YAP ameliorated cardiac hypertrophy and contractile dysfunction and attenuated accumulation of autophagosomes without affecting lysosomal function, suggesting that YAP plays an important role in mediating cardiomyopathy in RagA/B cKO mice. Cardiomyopathy was also alleviated by downregulation of Atg7, an intervention to inhibit autophagy, whereas it was exacerbated by stimulation of autophagy. YAP physically interacted with transcription factor EB (TFEB), a master transcription factor that controls autophagic and lysosomal gene expression, thereby facilitating accumulation of autophagosomes without degradation. These results indicate that accumulation of YAP in the presence of LSD promotes cardiomyopathy by stimulating accumulation of autophagosomes through activation of TFEB.

The contemporary pulmonary artery catheter. Part 1: placement and waveform analysis

Nowadays, the classical pulmonary artery catheter (PAC) has an almost 50-year-old history of its clinical use for hemodynamic monitoring. In recent years, the PAC evolved from a device that enabled intermittent cardiac output measurements in combination with static pressures to a monitoring tool that provides continuous data on cardiac output, oxygen supply and-demand balance, as well as right ventricular (RV) performance. In this review, which consists of two parts, we will introduce the difference between intermittent pulmonary artery thermodilution using cold bolus injections, and the contemporary PAC enabling continuous measurements by using a thermal filament which at random heats up the blood. In this first part, the insertion techniques, interpretation of waveforms of the PAC, the interaction of waveforms with the respiratory cycle and airway pressure as well as pitfalls in waveform analysis are discussed. The second part will cover the measurements of the contemporary PAC including measurement of continuous cardiac output, RV ejection fraction, end-diastolic volume index, and mixed venous oxygen saturation. Limitations of all of these measurements will be highlighted there as well. We conclude that thorough understanding of measurements obtained from the PAC are the first step in successful application of the PAC in daily clinical practice.

Overview of Cardiomyopathies in Childhood

Paediatric cardiomyopathies are a heterogenous group of rare disorders, characterised by mechanical and electrical abnormalities of the heart muscle. The overall annual incidence of childhood cardiomyopathies is estimated at about 1 per 100,000 children and is significantly higher during the first 2 years of life. Dilated cardiomyopathies account for approximately half of the cases. Hypertrophic cardiomyopathies form the second largest group, followed by the less common left ventricular non-compaction and restrictive phenotypes. Infectious, metabolic, genetic, and syndromic conditions account for the majority of cases. Congestive heart failure is the typical manifestation in children with dilated cardiomyopathy, whereas presenting symptoms are more variable in other phenotypes. The natural history is largely influenced by the type of cardiomyopathy and its underlying aetiology. Results from a national population-based study revealed 10-year transplant-free survival rates of 80, 62, and 48% for hypertrophic, dilated and left ventricular non-compaction cardiomyopathies, respectively. Long-term survival rates of children with a restrictive phenotype have largely been obscured by early listing for heart transplantation. In general, the majority of adverse events, including death and heart transplantation, occur during the first 2 years after the initial presentation. This review provides an overview of childhood cardiomyopathies with a focus on epidemiology, natural history, and outcomes.

Different Pathophysiology and Outcomes of Heart Failure With Preserved Ejection Fraction Stratified by K-Means Clustering

Background: Stratified medicine may enable the development of effective treatments for particular groups of patients with heart failure with preserved ejection fraction (HFpEF); however, the heterogeneity of this syndrome makes it difficult to group patients together by common disease features. The aim of the present study was to find new subgroups of HFpEF using machine learning. Methods: K-means clustering was used to stratify patients with HFpEF. We retrospectively enrolled 350 outpatients with HFpEF. Their clinical characteristics, blood sample test results and hemodynamic parameters assessed by echocardiography, electrocardiography and jugular venous pulse, and clinical outcomes were applied to k-means clustering. The optimal k was detected using Hartigan's rule. Results: HFpEF was stratified into four groups. The characteristic feature in group 1 was left ventricular relaxation abnormality. Compared with group 1, patients in groups 2, 3, and 4 had a high mean mitral E/e' ratio. The estimated glomerular filtration rate was lower in group 2 than in group 3 (median 51 ml/min/1.73 m² vs. 63 ml/min/1.73 m² p < 0.05). The prevalence of less-distensible right ventricle and atrial fibrillation was higher, and the deceleration time of mitral inflow was shorter in group 3 than in group 2 (93 vs. 22% p < 0.05, 95 vs. 1% p < 0.05, and median 167 vs. 223 ms p < 0.05, respectively). Group 4 was characterized by older age (median 85 years) and had a high systolic pulmonary arterial pressure (median 37 mmHg), less-distensible right ventricle (89%) and renal dysfunction (median 54 ml/min/1.73 m²). Compared with group 1, group 4 exhibited the highest risk of the cardiac events (hazard ratio [HR]: 19; 95% confidence interval [CI] 8.9-41); group 2 and 3 demonstrated similar rates of cardiac events (group 2 HR: 5.1; 95% CI 2.2-12; group 3 HR: 3.7; 95%CI, 1.3-10). The event-free rates were the lowest in group 4 (p for trend < 0.001). Conclusions: K-means clustering divided HFpEF into 4 groups. Older patients with HFpEF may suffer from complication of RV afterload mismatch and renal dysfunction. Our study may be useful for stratified medicine for HFpEF.

Epidemiology of cardiomyopathies: essential context knowledge for a tailored clinical work-up

Cardiomyopathies (CMPs) are primary disorders of myocardial structure and function in the absence of coronary artery disease, hypertension, valvular disease, and congenital heart disease. Knowledge of the incidence and prevalence of CMPs may help clinicians to compare their observations in clinical practice with expected cases per person-year and to avoid under-reporting in clinical context. Currently, available estimates of prevalence and incidence of CMPs are based on clinical data, collected with a wide variability in population-source, and before the genetic testing evolved as a standard diagnostic tool. This review focuses on the epidemiology of CMPs in subjects aged between 18 and 55 years. A structured up-to-date diagnostic flow-chart for CMPs diagnosis and assessment is proposed to avoid misdiagnosis of CMPs in the young population and in subjects with unexplained cardiac disorders.

Iliocaval Venous Obstruction, Cardiac Preload Reserve and Exercise Limitation

Cardiac output during exercise increases by as much as fivefold in the untrained man, and by as much as eightfold in the elite athlete. Increasing venous return is a critical but much overlooked component of the physiological response to exercise. Cardiac disorders such as constrictive pericarditis, restrictive cardiomyopathy and pulmonary hypertension are recognised to impair preload and cause exercise limitation; however, the effects of peripheral venous obstruction on cardiac function have not been well described. This manuscript will discuss how obstruction of the iliocaval venous outflow can lead to impairment in exercise tolerance, how such obstructions may be diagnosed, the potential implications of chronic obstructions on sympathetic nervous system activation, and relevance of venous compression syndromes in heart failure with preserved ejection fraction.

Idiopathic endomyocardial fibrosis in a Western European: a case report

Background

Endomyocardial fibrosis (EMF) is a rare cause of restrictive cardiomyopathy, mainly found in tropical/subtropical country. Endomyocardial fibrosis causes severe congestive symptoms and may lead to end-stage heart failure.

Case summary

A French Caucasian 44-year-old man without noticeable medical history and who had never travelled outside of France was hospitalized for a first episode of acute heart failure revealing an atypical appearance of the left ventricle. Cardiac magnetic resonance (CMR) identified EMF, but investigations did not identify any aetiology (no eosinophilia). Despite optimal management of chronic heart failure, functional class declined rapidly resulting in several hospitalizations for heart failure. The patient finally underwent an elective heart transplantation with good results at 6-month follow-up.

Discussion

Endomyocardial fibrosis exact physiopathology remains unclear, although association with eosinophilia has been reported. Diagnosis is challenging and is based on multi-modal imagery with a central role of CMR. There is no consensus on optimal management, medical therapy having poor outcomes and rate of peri-operative complications being high. Heart transplantation should be considered for eligible patients.

Comprehensive Assessment of Endomyocardial Fibrosis with Cardiac MRI: Morphology, Function, and Tissue Characterization

Endomyocardial fibrosis (EMF) affects approximately 12 million persons worldwide and is an important cause of restrictive cardiomyopathy in the developing world, with the highest prevalence reported in sub-Saharan Africa, South Asia, and South America. EMF is characterized by apical filling with fibrotic tissue of one or both ventricles, often associated with thrombus, calcification, and atrioventricular valve regurgitation, leading to typical symptoms of restrictive heart failure. Transthoracic echocardiography (TTE) is the first-line modality for assessment of EMF, basically owing to its widespread availability. However, in recent years cardiac MRI has emerged as a powerful tool for assessment of cardiac morphology and function, with higher accuracy than TTE, along with the unique advantage of being able to provide comprehensive noninvasive tissue characterization. Delayed enhancement (DE) imaging is the cornerstone of cardiac MRI tissue characterization and allows accurate identification of myocardial fibrosis, conveying valuable additional diagnostic and prognostic information. The typical DE pattern in EMF, described as the "double V" sign, consists of a three-layered pattern of normal myocardium, thickened enhanced endomyocardium, and overlying thrombus at the apex of the affected ventricle; it has excellent correlation with histopathologic findings and plays an important role in differentiating EMF from other cardiomyopathies. Conversely, fibrous tissue deposition quantified using DE imaging, when indexed to body surface area, has been shown to be a strong independent predictor of mortality. The aim of this review is to summarize state-of-the-art applications of cardiac MRI for diagnostic and prognostic assessment of patients with suspected or confirmed EMF. Online supplemental material is available for this article. ^©RSNA, 2020.

A case presentation of patient from northern China with endomyocardial fibrosis

Background

Endomyocardial fibrosis (EMF) is a rare condition and a major cause of death in tropical countries. The etiology of EMF remains elusive, and no specific treatment has been developed yet, therefore it carries poor prognosis.

Case presentation

An 81-year-old male Chinese patient with a history of long-standing exertional breathlessness, presented with worsening symptoms rapidly evolving to orthopnea. A proper specific treatment was prescribed to the patient in the following days, including diuretics, angiotensin-converting-enzyme inhibitor and beta blockers. The patient died of progressive multiple organ failure.

Conclusion

Echocardiography is technically limited due to the acoustic shadowing as a result of the calcification. Chest computed tomography is a more accurate diagnostic tool to examine the anatomic distribution and extent of endomyocardial calcification in this rare case.

Genetics of dilated cardiomyopathy: practical implications for heart failure management

Given the global burden of heart failure, strategies to understand the underlying cause or to provide prognostic information are critical to reducing the morbidity and mortality associated with this highly prevalent disease. Cardiomyopathies often have a genetic cause, and the field of heart failure genetics is progressing rapidly. Through a deliberate investigation, evaluation for a familial component of cardiomyopathy can lead to increased identification of pathogenic genetic variants. Much research has also been focused on identifying markers of risk in patients with cardiomyopathy with the use of genetic testing. Advances in our understanding of genetic variants have been slightly offset by an increased recognition of the heterogeneity of disease expression. Greater breadth of genetic testing can increase the likelihood of identifying a variant of uncertain significance, which is resolved only rarely by cellular functional validation and segregation analysis. To increase the use of genetics in heart failure clinics, increased availability of genetic counsellors and other providers with experience in genetics is necessary. Ultimately, through ongoing research and increased clinical experience in cardiomyopathy genetics, an improved understanding of the disease processes will facilitate better clinical decision-making about the therapies offered, exemplifying the implementation of precision medicine.

Exercise Rehabilitation Improves Cardiac Volumes and Functional Capacity in Patients With Endomyocardial Fibrosis: A RANDOMIZED CONTROLLED TRIAL

PURPOSE

Endomyocardial fibrosis (EMF) is a restrictive cardiomyopathy associated with low functional capacity and high mortality rates. Exercise training has been proved to be a nonpharmacological treatment of cardiovascular diseases. Therefore, the purpose of this study was to determine the effects of exercise rehabilitation in EMF patients.

METHODS

Twenty-two EMF patients, functional classes II and III (New York Heart Association [NYHA]), were randomized to the control (C-EMF) or exercise rehabilitation (Rehab-EMF) group. Patients in the Rehab-EMF group underwent 4 mo of exercise rehabilitation, whereas patients in the C-EMF group were instructed to maintain their usual daily routine. Peak oxygen uptake ((Equation is included in full-text article.)O2), cardiac function, and quality of life were evaluated. All assessments were performed at baseline and after 4 mo.

RESULTS

After 4 mo of rehabilitation, peak (Equation is included in full-text article.)O2 increased in the Rehab-EMF group (17.4 ± 3.0 to 19.7 ± 4.4 mL/kg/min, P < .001), whereas the C-EMF group showed no difference (15.3 ± 3.0 to 15.0 ± 2.0 mL/kg/min, P = .87). Also, post-intervention, peak (Equation is included in full-text article.)O2 in the Rehab-EMF group was greater than that in the C-EMF group (P < .001). Furthermore, the Rehab-EMF group, when compared to the C-EMF group, showed an increase in left ventricular end-diastolic volume (102.1 ± 64.6 to 136.2 ± 75.8 mL vs 114.4 ± 55.0 to 100.4 ± 49.9 mL, P < .001, respectively) and decrease in left atrial diastolic volume (69.0 ± 33.0 to 34.9 ± 15.0 mL vs 44.6 ± 21.0 to 45.6 ± 23.0 mL, P < .001, respectively). Quality-of-life scores also improved in the Rehab-EMF group, whereas the C-EMF group showed no change (45 ± 23 to 27 ± 15 vs 47 ± 15 to 45 ± 17, P < .001, respectively).

CONCLUSION

Exercise rehabilitation is a nonpharmacological intervention that improves functional capacity, cardiac volumes, and quality of life in EMF patients after endocardial resection surgery. In addition, exercise rehabilitation should be prescribed to EMF patients to improve their clinical condition.

Mechanical Circulatory Support Device Utilization and Heart Transplant Waitlist Outcomes in Patients With Restrictive and Hypertrophic Cardiomyopathy

BACKGROUND

Patients with restrictive cardiomyopathy (RCM) and hypertrophic cardiomyopathy (HCM) generally are considered poor candidates for mechanical circulatory support devices (MCSDs) and often not able to be bridged mechanically to heart transplantation. This study characterized MCSD utilization and transplant waitlist outcomes in patients with RCM/HCM under the current allocation system and discusses changes in the era of the new donor allocation system.

METHODS AND RESULTS

Patients waitlisted from 2006 to 2016 in the United Network for Organ Sharing registry were stratified by RCM/HCM versus other diagnoses. MCSD utilization and waitlist duration were analyzed by propensity score models. Waitlist outcomes were assessed by cumulative incidence functions with competing events. Predictors of waitlist mortality or delisting for worsening status in patients with RCM/HCM were identified by proportional hazards model. Of 30 608 patients on the waitlist, 5.1% had RCM/HCM. Patients with RCM/HCM had 31 fewer waitlist days (P<0.01) and were ≈26% less likely to receive MCSD (P<0.01). Cumulative incidence of waitlist mortality was similar between cohorts; however, patients with RCM/HCM had higher incidence of heart transplantation. Predictors of waitlist mortality or delisting for worsening status in patients with RCM/HCM without MCSD support included estimated glomerular filtration rate <60 mL/min per 1.73 m², pulmonary capillary wedge pressure >20 mm Hg, inotrope use, and subjective frailty.

CONCLUSIONS

Patients with RCM/HCM are less likely to receive MCSD but have similar waitlist mortality and slightly higher incidence of transplantation compared with other patients. The United Network for Organ Sharing RCM/HCM risk model can help identify patients who are at high risk for clinical deterioration and in need of expedited heart transplantation.

Updates on the Genetic Paradigm in Heart Failure

PURPOSE OF REVIEW

The rapidly evolving field of cardiovascular genetics has already improved the care of patients with heart failure and families. The purpose of the current review is to describe the most and provide the most pertinent updates in the field of heart failure genetics.

RECENT FINDINGS

Recent advanced in heart failure genetics have begun to not only increase the yield of testing through improving technology and use of whole exome or whole genome screening, but also enabled the improving technology and increasing use of whole exome or whole genome screening, but also enabled an enhanced understanding of the implications of results of genetic testing. For instance, new data have described differential responses to heart failure therapies based on genetic testing. Additionally, variant analysis by locus in genetic cardiomyopathies has facilitated a much-improved prognostic understanding of phenotype. Recent years have seen advancements in the understanding of the genetics of rare disorders, including pediatric-onset cardiomyopathies, previously under-investigated; restrictive cardiomyopathies; and non-compaction cardiomyopathy. The last few years have heralded not only a broader understanding of the scope of the genetics of heart failure, but have also provided notable leaps in mechanistic and prognostic understanding, which will serve as the foundation for clinical investigation and future genetic variant assessment.

Prominent 'Y' descent is an ominous sign of a poorer prognosis in heart failure with preserved ejection fraction

AIMS

The heterogeneity of heart failure with preserved ejection fraction (HFpEF) represents different pathophysiological paths by which individual patients develop heart failure. The deterioration mechanisms are considered to be mainly left ventricular diastolic dysfunction, right ventricular (RV) systolic function, and RV afterload. It is unclear whether RV distensibility affects the deterioration of HFpEF. Our study aimed to clarify whether impaired RV distensibility is associated with the deterioration of HFpEF.

METHODS AND RESULTS

We retrospectively enrolled 322 patients with HFpEF and examined their echocardiography results, electrocardiograms, phonocardiograms, and jugular venous pulse waves. Using signal-processing techniques, the prominent 'Y' descent of the jugular venous waveform was detected as an established haemodynamic sign of a less-distensible right ventricle. We defined cardiovascular events of HFpEF as follows: sudden death, death from heart failure, or hospitalization for HFpEF. During a mean follow-up period of 33 ± 20 months, 73 patients had cardiovascular events of HFpEF. The prevalence of a less-distensible right ventricle and the variables of RV systolic pressure were independent risk factors for cardiovascular events (hazard ratio, 2.046, P = 0.005, and hazard ratio, 1.032 per 1 mmHg, P = 0.002, respectively). The event-free rate of HFpEF was the lowest for HFpEF with a less-distensible right ventricle and elevated RV systolic pressure (≥35 mmHg) (P for trend <0.001).

CONCLUSIONS

A less-distensible right ventricle and elevated RV systolic pressure were found to be closely associated with the deterioration of HFpEF. Assessment of a less-distensible right ventricle may help to stratify patients and improve therapeutic strategies for HFpEF.

AUTOMATED CHARACTERIZATION OF CARDIOVASCULAR DISEASES USING WAVELET TRANSFORM FEATURES EXTRACTED FROM ECG SIGNALS

Cardiovascular disease has been the leading cause of death worldwide. Electrocardiogram (ECG)-based heart disease diagnosis is simple, fast, cost effective and non-invasive. However, interpreting ECG waveforms can be taxing for a clinician who has to deal with hundreds of patients during a day. We propose computing machinery to reduce the workload of clinicians and to streamline the clinical work processes. Replacing human labor with machine work can lead to cost savings. Furthermore, it is possible to improve the diagnosis quality by reducing inter- and intra-observer variability. To support that claim, we created a computer program that recognizes normal, Dilated Cardiomyopathy (DCM), Hypertrophic Cardiomyopathy (HCM) or Myocardial Infarction (MI) ECG signals. The computer program combined Discrete Wavelet Transform (DWT) based feature extraction and K-Nearest Neighbor (K-NN) classification for discriminating the signal classes. The system was verified with tenfold cross validation based on labeled data from the PTB diagnostic ECG database. During the validation, we adjusted the number of neighbors [Formula: see text] for the machine learning algorithm. For [Formula: see text], training set has an accuracy and cross validation of 98.33% and 95%, respectively. However, when [Formula: see text], it showed constant for training set but dropped drastically to 80% for cross-validation. Hence, training set [Formula: see text] prevails. Furthermore, a confusion matrix proved that normal data was identified with 96.7% accuracy, 99.6% sensitivity and 99.4% specificity. This means an error of 3.3% will occur. For every 30 normal signals, the classifier will mislabel only 1 of the them as HCM. With these results, we are confident that the proposed system can improve the speed and accuracy with which normal and diseased subjects are identified. Diseased subjects can be treated earlier which improves their probability of survival.

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.

Translating emerging molecular genetic insights into clinical practice in inherited cardiomyopathies

Cardiomyopathies are primarily genetic disorders of the myocardium associated with higher risk of life-threatening cardiac arrhythmias, heart failure, and sudden cardiac death. The evolving knowledge in genomic medicine during the last decade has reshaped our understanding of cardiomyopathies as diseases of multifactorial nature and complex pathophysiology. Genetic testing in cardiomyopathies has subsequently grown from primarily a research tool into an essential clinical evaluation piece with important clinical implications for patients and their families. The purpose of this review is to provide with a contemporary insight into the implications of genetic testing in diagnosis, therapy, and prognosis of patients with inherited cardiomyopathies. Here, we summarize the contemporary knowledge on genotype-phenotype correlations in inherited cardiomyopathies and highlight the recent significant achievements in the field of translational cardiovascular genetics.

Multimodality Imaging in Restrictive Cardiomyopathies: An EACVI expert consensus document In collaboration with the "Working Group on myocardial and pericardial diseases" of the European Society of Cardiology Endorsed by The Indian Academy of Echocardiography

Restrictive cardiomyopathies (RCMs) are a diverse group of myocardial diseases with a wide range of aetiologies, including familial, genetic and acquired diseases and ranging from very rare to relatively frequent cardiac disorders. In all these diseases, imaging techniques play a central role. Advanced imaging techniques provide important novel data on the diagnostic and prognostic assessment of RCMs. This EACVI consensus document provides comprehensive information for the appropriateness of all non-invasive imaging techniques for the diagnosis, prognostic evaluation, and management of patients with RCM.

Acquired Cardiac Disease in the Pediatric Intensive Care Unit

This review focuses on the identification, evaluation, management, and stabilization of a variety of acquired cardiac conditions, such as cardiomyopathies, inflammatory cardiac disease, and Kawasaki disease, which commonly require care in the pediatric intensive care unit (PICU). Pediatric cardiomyopathies comprise a spectrum of acquired or congenital myocardial diseases in which there are abnormalities of cardiac size and ventricular wall thickness, along with ventricular performance. The inflammatory diseases of the heart include acute myocarditis and pericarditis. Cardiac sequelae of Kawasaki disease resemble a self-limited vasculitis, but in rare instances may present with hemodynamic instability requiring vasopressor support. Care in the PICU affords both monitoring and management opportunities. [Pediatr Ann. 2018;47(7):e280-e285.].