Dilated cardiomyopathy and myocarditis in Kenya: an endomyocardial biopsy study

Exosomal Cargo: Pro-angiogeneic, anti-inflammatory, and regenerative effects in ischemic and non-ischemic heart diseases - A comprehensive review

Heart diseases are the primary cause of mortality and morbidity worldwide which inflict a heavy social and economic burden. Among heart diseases, most deaths are due to myocardial infarction (MI) or heart attack, which occurs when a decrement in blood flow to the heart causes injury to cardiac tissue. Despite several available diagnostic, therapeutic, and prognostic approaches, heart disease remains a significant concern. Exosomes are a kind of small extracellular vesicles released by different types of cells that play a part in intercellular communication by transferring bioactive molecules important in regenerative medicine. Many studies have reported the diagnostic, therapeutic, and prognostic role of exosomes in various heart diseases. Herein, we reviewed the roles of exosomes as new emerging agents in various types of heart diseases, including ischemic heart disease, cardiomyopathy, arrhythmia, and valvular disease, focusing on pathogenesis, therapeutic, diagnostic, and prognostic roles in different areas. We have also mentioned different routes of exosome delivery to target tissues, the effects of preconditioning and modification on exosome's capability, exosome production in compliance with good manufacturing practice (GMP), and their ongoing clinical applications in various medical contexts to shed light on possible clinical translation.

Right ventricular free wall strain in acutely decompensated heart failure patients with ischemic and non-ischemic cardiomyopathy

AIMS

Right ventricular (RV) dysfunction is a predictor of adverse outcomes among patients with HF with reduced ejection fraction (HFrEF); however, differences in RV parameters in HFrEF patients with ischemic (ICM) and non-ischemic cardiomyopathies (NICM) are not well understood. We investigated echocardiographic characteristics, including RV strain, in patients with acute decompensated heart failure (ADHF) and compared patients with ICM and NICM etiology.

METHODS

Consecutive patients who presented with ADHF and NYHA class III-IV were prospectively enrolled if they had LVEF < 40% and history of ICM or NICM. All patients underwent clinical exam, laboratory evaluation and 2-D echocardiographic assessment of the left ventricular (LV) and RV function, LV and RV global longitudinal strain (LVGLS, RVGLS), and RV free wall strain (RVfwLS).

RESULTS

Of 84 patients, 44 had ICM and 40 NICM. The groups had similar blood pressure, NT-proBNP, and echocardiographic parameters of LV function including LVGLS. Absolute RVGLS values were lower than RVfwLS values in both groups. Patients with NICM had significantly lower RVfwLS, but not RVGLS, compared to patients with ICM (-13% to -17%, p = 0.006). Similar differences in RVfwLS were seen in patients in NYHA class III (NICM vs ICM: -13% and -17%, respectively, 95% CI: -8.5 to -.5) and NYHA class IV (NICM vs ICM: -13.8% and -17%, respectively, 95% CI: -6.4 to -.59).

CONCLUSION

Among patients hospitalized with ADHF, patients with nonischemic etiology compared with the patients with ICM, have more severe RV dysfunction measured by RVfwLS, despite similar extent of LV impairment and the same functional limitation class.

Ghrelin Derangements in Idiopathic Dilated Cardiomyopathy: Impact of Myocardial Disease Duration and Left Ventricular Ejection Fraction

Background: Ghrelin may exert positive effects on cardiac structure and function in heart failure (HF) patients. Methods: We assessed ghrelin levels in 266 dilated cardiomyopathy (DCM) patients and in 200 age, gender and body mass index (BMI) matched controls. Further, we evaluated the expression of ghrelin and growth hormone secretagogue-receptor (GHSR) in the myocardium of 41 DCM patients and in 11 controls. Results: DCM patients had significantly lower levels of total, acylated and unacylated ghrelin when compared to controls (p < 0.05 for all). In controls, we observed a negative correlation of ghrelin with age, male gender and BMI. These correlations were lost in the DCM group, except for male gender. Total ghrelin was higher in patients with more recent diagnosis when compared to patients with longer duration of the DCM (p = 0.033). Further, total ghrelin was higher in patients with lower left ventricular systolic function (<40% LVEF, vs. 40% ≤ LVEF < 49% vs. LVEF ≥ 50%: 480.8, vs. 429.7, vs. 329.5 pg/mL, respectively, p = 0.05). Ghrelin prepropeptide was expressed more in DCM patients than in controls (p = 0.0293) while GHSR was expressed less in DCM patients (p < 0.001). Furthermore, ghrelin showed an inverse correlation with its receptor (ρ = −0.406, p = 0.009), and this receptor showed a significant inverse correlation with Interleukin-1β (ρ = −0.422, p = 0.0103). Conclusion: DCM duration and severity are accompanied by alterations in the ghrelin–GHSR system.

Histopathological and Morphometric Study of Fibrosis and Nuclear Pleomorphism in Dilated Cardiomyopathy

Histopathological changes associated with dilated cardiomyopathy (CMD) are frequently nonspecific and often only present in the terminal stage of the disease. The study followed the histopathological and morphometric quantification of fibrosis and nuclear pleomorphism in CMD. We analyzed left ventricle myocardial fragments harvested during autopsy, from 35 cases with clinical diagnosis of CMD and 5 cases of normal myocardium. Fibrosis was present in all CMD cases, with higher values compared with control cases. Nuclear pleomorphism was identified in 18 cases (45%), two of the analyzed parameters, respectively the ratio of nuclear diameters and roundness of nucleus, revealing significant differences in CMD compared to the control cases. Myocardial fibrosis present in all cases of CMD represents a major feature of the disease. The nuclear pleomorphism due to the nuclei change in diameters and size was more pronounced in the vicinity of fibrosis areas, possibly related to this alteration.

Optimal site selection and image fusion guidance technology to facilitate cardiac resynchronization therapy

INTRODUCTION

Cardiac resynchronization therapy (CRT) has emerged as one of the few effective treatments for heart failure. However, up to 50% of patients derive no benefit. Suboptimal left ventricle (LV) lead position is a potential cause of poor outcomes while targeted lead deployment has been associated with enhanced response rates. Image-fusion guidance systems represent a novel approach to CRT delivery, allowing physicians to both accurately track and target a specific location during LV lead deployment.

AREAS COVERED

This review will provide a comprehensive evaluation of how to define the optimal pacing site. We will evaluate the evidence for delivering targeted LV stimulation at sites displaying favorable viability or advantageous mechanical or electrical properties. Finally, we will evaluate several emerging image-fusion guidance systems which aim to facilitate optimal site selection during CRT.

EXPERT COMMENTARY

Targeted LV lead deployment is associated with reductions in morbidity and mortality. Assessment of tissue characterization and electrical latency are critical and can be achieved in a number of ways. Ultimately, the constraints of coronary sinus anatomy have forced the exploration of novel means of delivering CRT including endocardial pacing which hold promise for the future of CRT delivery.

Histopathological Aspects of the Myocardium in Dilated Cardiomyopathy

Dilated cardiomyopathy is the most common form of cardiac muscle disease, accounting for approximately 60% of all cardiomyopathies. We proposed to identify histopathological changes of the myocardium in dilative cardiomyopathy. This study comprised a total of 19 cases, represented by myocardial fragments from deceased patients with diagnosis of dilated cardiomyopathy. Histopathological analysis allowed changes to be observed for both myocytes and myocardial interstitial components. We have found a combination of hypertrophic, atrophic and normal myocardocytes, or associated with the presence of hydropic changes. We rarely identified the aspect of myocytosis, cytoplasmic accumulation of lipofuscin pigment or mucinous material, and variable nuclear pleomorphism. At the interstitial level we noticed changes in fibrosis, lipomatosis and rarely the presence of inflammatory infiltrate. Histopathological characteristics of the myocardium in dilated cardiomyopathy are numerous but nonspecific, similar to those in the terminal stages of other cardiac diseases.

The global burden of myocarditis: part 1: a systematic literature review for the Global Burden of Diseases, Injuries, and Risk Factors 2010 study

Myocarditis contributes to the global burden of cardiovascular disease primarily through sudden death and dilated cardiomyopathy. A systematic approach to identify the cardiovascular mortality and major morbidity attributable to myocarditis has not been performed. A writing group convened by the GBD 2010 (Global Burden of Diseases, Injuries and Risk Factors) Study systematically reviewed the world's literature by a manual review of all titles since 1966 on myocarditis identified using Ovid Medline, development of a disease model, and provision of estimates when possible of the incidence, prevalence, risk of death, and major morbidity for the world regions. Accurate population-based estimates of myocarditis incidence and prevalence are not directly available in any world region. However, a model that quantitates the risk of acute death and chronic heart failure following myocarditis was derived from the published data. Using hospital dismissal data, the burden of myocarditis as a percentage of prevalent heart failure varied by age and region from approximately 0.5% to 4.0%. The novel combination of multiple data sources may provide an estimate of the years of life lost and years of life disabled from myocarditis. Pending the integration of these data sources, the burden of dilated cardiomyopathy and myocarditis were reported together in the 2010 GBD report. The 2013 GBD project may refine these estimates with the inclusion of more comprehensive payor databases and more precise case definitions.

Cardiomyopathies: Evolution of pathogenesis concepts and potential for new therapies

Cardiomyopathies are defined as diseases of the myocardium with associated structural and functional abnormalities. Knowledge of these pathologies for a long period was not clear in clinical practice due to uncertainties regarding definition, classification and clinical diagnosis. In recent decades, major advances have been made in the understanding of the molecular and genetic issues, pathophysiology, and clinical and radiological assessment of the diseases. Progress has been made also in management of several types of cardiomyopathy. Advances in the understanding of these diseases show that cardiomyopathies represent complex entities. Here, special attention is given to evolution of classification of cardiomyopathies, with the aim of assisting clinicians to look beyond schematic diagnostic labels in order to achieve more specific diagnosis. Knowledge of the genotype of cardiomyopathies has changed the pathophysiological understanding of their etiology and clinical course, and has become more important in clinical practice for diagnosis and prevention of cardiomyopathies. New approaches for clinical and prognostic assessment are provided based on contemporary molecular mechanisms of contribution in the pathogenesis of cardiomyopathies. The genotype-phenotype complex approach for assessment improves the clinical evaluation and management strategies of these pathologies. The review covers also the important role of imaging methods, particularly echocardiography, and cardiac magnetic resonance imaging in the evaluation of different types of cardiomyopathies. In summary, this review provides complex presentation of current state of cardiomyopathies from genetics to management aspects for cardiovascular specialists.

Prevalence of myocarditis and cardiotropic virus infection in Africans with HIV-associated cardiomyopathy, idiopathic dilated cardiomyopathy and heart transplant recipients: a pilot study: cardiovascular topic

Background:

The prevalence of myocarditis and cardiotropic viral infection in human immunodeficiency virus (HIV)-associated cardiomyopathy is unknown in Africa.

Methods

Between April 2002 and December 2007, we compared the prevalence of myocarditis and cardiotropic viral genomes in HIV-associated cardiomyopathy cases with HIV-negative idiopathic dilated cardiomyopathy patients (i.e. negative controls for immunodeficiency) and heart transplant recipients (i.e. positive controls for immunodeficiency) who were seen at Groote Schuur Hospital, Cape Town, South Africa. Myocarditis was sought on endomyocardial biopsy using the imunohistological criteria of the World Heart Federation in 33 patients, 14 of whom had HIV-associated cardiomyopathy, eight with idiopathic dilated cardiomyopathy and 11 heart transplant recipients.

Results

Myocarditis was present in 44% of HIV-associated cardiomyopathy cases, 36% of heart transplant recipients, and 25% of participants with idiopathic dilated cardiomyopathy. While myocarditis was acute in 50% of HIV- and heart transplant-associated myocarditis, it was chronic in all those with idiopathic dilated cardiomyopathy. Cardiotropic viral infection was present in all HIV-associated cardiomyopathy and idiopathic dilated cardiomyopathy cases, and in 90% of heart transplant recipients. Multiple viruses were identified in the majority of cases, with HIV-associated cardiomyopathy, heart transplant recipients and idiopathic dilated cardiomyopathy patients having an average of 2.5, 2.2 and 1.1 viruses per individual, respectively.

Conclusions

Acute myocarditis was present in 21% of cases of HIV-associated cardiomyopathy, compared to none of those with idiopathic dilated cardiomyopathy. Infection with multiple cardiotropic viruses may be ubiquitous in Africans, with a greater burden of infection in acquired immunodeficiency states.

Cardiomyopathies and myocardial disorders in Africa: present status and the way forward

Abstract

A review of heart diseases in Africa shows that the cardiomyopathies continue to be important causes of morbidity and mortality in the population. Hypertension remains the commonest cause of myocardial disease, followed by the cardiomyopathies. Ischaemic heart disease continues to be rare. Of the cardiomyopathies, dilated cardiomyopathy (DCM) is still the commonest. A large proportion of patients diagnosed with DCM in Africa have been shown to be cases of hypertensive heart failure, with varying degrees of myocardial dysfunction. Hypertrophic cardiomyopathy, which in the past was thought to be rare among Africans, has been shown to have the same prevalence as in other parts of the world. Moreover it is now known to be a genetic disorder. Endomyocardial fibrosis has become rare in communities where it used to be common. Its aetiology continues to be elusive. Arrhythmogenic right ventricular cardiomyopathy has been reported among Africans but there are no reports of left ventricular non-compaction or the ion channelopathies from Africa. Lenegre disease and the long-QT syndromes are well-known entities in clinical practice in Africa although long-QT in Africa is associated with potassium deficiency arising from prolonged treatment with diuretics. Left ventricular non-ischaemic aneurysms still occur but are rare. In view of these, a new classification of myocardial disorders was proposed for Africa.

Cardiomyopathies and myocardial disorders in Africa: present status and the way forward

A review of heart diseases in Africa shows that the cardiomyopathies continue to be important causes of morbidity and mortality in the population. Hypertension remains the commonest cause of myocardial disease, followed by the cardiomyopathies. Ischaemic heart disease continues to be rare. Of the cardiomyopathies, dilated cardiomyopathy (DCM) is still the commonest. A large proportion of patients diagnosed with DCM in Africa have been shown to be cases of hypertensive heart failure, with varying degrees of myocardial dysfunction. Hypertrophic cardiomyopathy, which in the past was thought to be rare among Africans, has been shown to have the same prevalence as in other parts of the world. Moreover it is now known to be a genetic disorder. Endomyocardial fibrosis has become rare in communities where it used to be common. Its aetiology continues to be elusive. Arrhythmogenic right ventricular cardiomyopathy has been reported among Africans but there are no reports of left ventricular non-compaction or the ion channelopathies from Africa. Lenegre disease and the long-QT syndromes are well-known entities in clinical practice in Africa although long-QT in Africa is associated with potassium deficiency arising from prolonged treatment with diuretics. Left ventricular non-ischaemic aneurysms still occur but are rare. In view of these, a new classification of myocardial disorders was proposed for Africa.

Heart failure in sub-Saharan Africa

The heart failure syndrome has been recognized as a significant contributor to cardiovascular disease burden in sub-Saharan African for many decades. Seminal knowledge regarding heart failure in the region came from case reports and case series of the early 20th century which identified infectious, nutritional and idiopathic causes as the most common. With increasing urbanization, changes in lifestyle habits, and ageing of the population, the spectrum of causes of HF has also expanded resulting in a significant burden of both communicable and non-communicable etiologies. Heart failure in sub-Saharan Africa is notable for the range of etiologies that concurrently exist as well as the healthcare environment marked by limited resources, weak national healthcare systems and a paucity of national level data on disease trends. With the recent publication of the first and largest multinational prospective registry of acute heart failure in sub-Saharan Africa, it is timely to review the state of knowledge to date and describe the myriad forms of heart failure in the region. This review discusses several forms of heart failure that are common in sub-Saharan Africa (e.g., rheumatic heart disease, hypertensive heart disease, pericardial disease, various dilated cardiomyopathies, HIV cardiomyopathy, hypertrophic cardiomyopathy, endomyocardial fibrosis, ischemic heart disease, cor pulmonale) and presents each form with regard to epidemiology, natural history, clinical characteristics, diagnostic considerations and therapies. Areas and approaches to fill the remaining gaps in knowledge are also offered herein highlighting the need for research that is driven by regional disease burden and needs.

Contemporary trends in the epidemiology and management of cardiomyopathy and pericarditis in sub-Saharan Africa

Heart failure in sub-Saharan Africans is mainly due to non-ischaemic causes, such as hypertension, rheumatic heart disease, cardiomyopathy and pericarditis. The two endemic diseases that are major contributors to the clinical syndrome of heart failure in Africa are cardiomyopathy and pericarditis. The major forms of endemic cardiomyopathy are idiopathic dilated cardiomyopathy, peripartum cardiomyopathy and endomyocardial fibrosis. Endomyocardial fibrosis, which affects children, has the worst prognosis. Other cardiomyopathies have similar epidemiological characteristics to those of other populations in the world. HIV infection is associated with occurrence of HIV-associated cardiomyopathy in patients with advanced immunosuppression, and the rise in the incidence of tuberculous pericarditis. HIV-associated tuberculous pericarditis is characterised by larger pericardial effusion, a greater frequency of myopericarditis, and a higher mortality than in people without AIDS. Population-based studies on the epidemiology of heart failure, cardiomyopathy and pericarditis in Africans, and studies of new interventions to reduce mortality, particularly in endomyocardial fibrosis and tuberculous pericarditis, are needed.

Epidemiology and Etiology of Cardiomyopathy in Africa

Background— Cardiomyopathy, an often irreversible form of heart muscle disease that is associated with a dismal outcome, is endemic in Africa. The primary objective of this review was to summarize the current state of knowledge on the epidemiology and etiology of cardiomyopathy in people living in Africa and to identify new avenues for research.

Methods and Results— We searched MEDLINE (January 1, 1966, through February 12, 2005) and reference lists of articles for relevant references. Unlike other parts of the world in which cardiomyopathy is rare, dilated cardiomyopathy is a major cause of heart failure throughout Africa. Similarly, peripartum cardiomyopathy is ubiquitous on the continent, with an incidence ranging from 1 in 100 to 1 in 1000 deliveries. There is an apparent marked regional variation in the pathogenesis of dilated cardiomyopathy and peripartum cardiomyopathy, underlining the heterogeneity of causative factors in these conditions. By contrast, endomyocardial fibrosis is restricted to the tropical regions of East, Central, and West Africa. Although the pathogenesis of endomyocardial fibrosis is not fully understood, it seems that the conditioning factors are geography and diet, the triggering factor may be an as yet unidentified infective agent, and the perpetuating factor is eosinophilia. Although epidemiological studies are lacking, hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy seem to have characteristics similar to those of other populations elsewhere in the world.

Conclusions— There is a need for large-scale epidemiological studies of the incidence, prevalence, determinants, and outcome of cardiomyopathy in Africa to inform strategies for the treatment and prevention of heart muscle disease on the continent.