Endomyocardial fibrosis in Africa

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.

Endomyocardial fibrosis

Background

Endomyocardial fibrosis (EMF) is a neglected cardiovascular disease of poverty which carries a poor prognosis with no specific treatment affecting mainly children and young adults. Here, we report our 10-year experience in the therapeutic management and surgical treatment for EMF.

Methods

From February 2009 to 2019 March, 55 patients diagnosed with EMF from our cardiology unit underwent surgical repair at our department's pediatric surgical division. There were 35 male, and 20 female patients whose ages varied from 1 year 2 months to 12 years mean age 5.7 (±3.2). We designed the study aimed at assessing the cardio-structural abnormalities and coronary vascular changes faced with EMF patients using echocardiography, and coronary angiography with a detailed and thorough surgical examination of each case.

Results

Of the 55 operated patients, 1 had mild lesions, 26 had moderate lesions, and 28 had severe heart disease. All but one patient was in NYHA functional class III or IV at the time of surgery. All but one female patient with mild ventricular lesions and no valvular involvement had severe atrioventricular valve regurgitation with valves considered suitable for both replacements; 45 patients mean age 6.0 (±3.1) and repair nine patients mean age 3.8 (±2.9). The mean endocardial thickness was 3,000 (±1519) µm.

Conclusions

The echocardiographic changes corresponded well to the findings on surgery and histopathology. The coronary changes seen included a spectrum of fibrin deposition, medial sclerosis and degeneration, and the formation of plexiform lesions. Surgically evaluating the resected cardiac tissue might help improve disease management.

Tropical Endomyocardial Fibrosis: Natural History, Challenges, and Perspectives

Tropical endomyocardial fibrosis (EMF) is a neglected disease of poverty that afflicts rural populations in tropical low-income countries, with some certain high-prevalence areas. Tropical EMF is characterized by the deposition of fibrous tissue in the endomyocardium, leading to restrictive physiology. Since the first descriptions in Uganda in 1948, high-frequency areas for EMF have included Africa, Asia, and South America. Although there is no clear consensus on a unified hypothesis, it seems likely that dietary, environmental, and infectious factors may combine in a susceptible individual to give rise to an inflammatory process leading to endomyocardial damage and scar formation. The natural history of EMF includes an active phase with recurrent flare-ups of inflammation evolving to a chronic phase leading to restrictive heart failure. In the chronic phase, biventricular involvement is the most common presentation, followed by isolated right-sided heart disease. Marked ascites out of proportion to peripheral edema usually develops as a typical feature of EMF. EMF carries a very poor prognosis. In addition to medical management of heart failure, early open heart surgery (endocardectomy and valve repair/replacement) appears to improve outcomes to some extent; however, surgery is technically challenging and not available in most endemic areas. Increased awareness among health workers and policy makers is the need of the hour for the unhindered development of efficient preventive and therapeutic strategies.

[Endomyocardial fibrosis in Cameroon: Echocardiographic and clinical description of a pediatric series in Yaoundé]

BACKGROUND

Endomyocardial fibrosis is a restrictive cardiomyopathy that causes heart failure. It is characterized by the fibrotic thickening of the endocardium, sometimes involving the myocardium as well. The lesion generally lies at the apices or inflow tracts of one or both ventricles, associated with more or less severe alteration of the valves. It is a disease of the intertropical regions but is not well known in Cameroon. In this study we describe the first series seen in a pediatric hospital in Cameroon.

PATIENTS AND METHODS

A retrospective study was conducted in a pediatric hospital in Yaoundé involving children who had been diagnosed with endomyocardial fibrosis after echocardiographic investigation. We collected the clinical and paraclinical data from consultation records and medical files.

RESULTS

Between January 2006 to December 2013, we registered 1430 patients with a cardiac anomaly in our center. Endomyocardial fibrosis was found in 46 patients. Neither sex predominated. Ages at the time of diagnosis varied between 2 and 17 years. Most of the patients were between 5 and 15 years old (80.4 %), with a median of 10 years (interquartile range, 7-13 years). The main complaints were breathlessness, cough, abdominal distension, abdominal, and loss of appetite. Apart from the hyperpigmentation of the lips observed in all our patients, dyspnea was the most frequent physical sign and the diagnosis was made at a time when signs of heart failure were preponderant. Growth retardation was found in all the children examined. All patients were underweight with a median weight for age found below the 25th percentile of the norms according to the National Health Statistics. Lower limb edema was absent even in the presence of voluminous ascites. All subjects had hyperpigmented lips. Despite the cyanotic appearance of the lips, pulse oximetry always gave a normal oxygen saturation level and no cyanosis was seen elsewhere. None of the patients had nail clubbing. Fibrosis more often affected the right ventricle (45/46 patients). The apical obliteration by fibrotic material was found in 43 (93.5 %) patients. Moreover, 36 (78.3 %) patients had pericardial effusion: mild to moderate in 32 subjects and abundant in four subjects. Hypereosinophilia was noted in 57.5 % of the patients. Atrial fibrillation was found in six out of 15 patients who had an electrocardiogram done.

CONCLUSION

The modes of clinical presentation of endomyocardial fibrosis are not sufficiently well known in our context. Despite its insidious progression, certain signs such as weight loss and hyperpigmented lips could be very helpful for screening and easing orientation of parents and heath personnel, thus enabling early referral for appropriate investigation. The presence of bulky ascites without edema of the lower extremities should be viewed as strongly suggestive.

Endomyocardial fibrosis in Sub Saharan Africa: The geographical origin, socioeconomic status, and dietary habits of cases reported in Yaounde, Cameroon

Background:

Endomyocardial fibrosis (EMF) is a neglected heart condition of the inter-tropical regions. Numerous hypotheses suggest a relationship between its geographical distribution in the affected regions and other etio-pathogenic factors such as dietary habits, infectious causes, and geochemical causes. Knowledge of its epidemiology in Cameroon remains limited, which is why we decided to describe the profile of a paediatric series of EMF in Yaoundé.

Patients and Methods:

A retrospective study was carried out on EMF in 54 patients diagnosed from 1 January 2006-31 December 2014 in a Paediatric Centre of Yaoundé. Diagnosis was mainly echocardiographic. We compiled data on the geographic origins of the patients, their dietary habits and the socioeconomic profile of their families.

Results:

The patients’ ages ranged from 2 to 17 years, most of whom (83.3%) were between 5 and 15 years. For geographical distribution, all came from three tropical forest zones where they have lived since their childhood. These were Center (32/54), South (12/54), and East (10/54). All families had a moderate income, consumed tubers at least twice a week especially cassava (43/54) and had low sources of proteins.

Conclusion:

Apart from geographical similarities all patients of our series shared the same dietary habits. Our study was conducted in a hospital setting; therefore a screening of the disease in the whole national territory would enable a more reliable mapping.

Endomyocardial fibrosis: A form of endemic restrictive cardiomyopathy

Endomyocardial fibrosis is a form of endemic restrictive cardiomyopathy that affects mainly children and adolescents, and is geographically restricted to some poor areas of Africa, Latin America and Asia. It is a condition with high morbidity and mortality, for which no effective therapy is available. Although several hypotheses have been proposed as triggers or causal factors for the disease, none are able to explain the occurrence of the disease worldwide. In endemic areas of Africa endomyocardial fibrosis is as common a cause of heart failure as rheumatic heart disease, accounting for up to 20% of cases of heart failure and imposes a considerable burden to the communities and the health systems. However, due to lack of resources for research in these areas, the exact epidemiology, etiology and pathogenesis remain unknown, and the natural history is incompletely understood. We here review the main aspects of epidemiology, natural history, clinical picture and management of endomyocardial fibrosis, proposing new ways to increase research into this challenging and neglected cardiovascular disease.

Epidemiology of heart failure in sub-Saharan Africa

Heart failure has emerged as a dominant form of cardiovascular disease in Africa, and has great social and economic relevance owing to its high prevalence, mortality and impact on young, economically active individuals. The causes of heart failure in Africans remain largely nonischemic. Hypertension, cardiomyopathy, rheumatic heart disease, chronic lung disease and pericardial disease are the main contributors to the etiology of cardiac failure in sub-Saharan Africa, accounting for over 90% of cases. Hypertensive heart disease complications occur more frequently in Africans and the majority of affected patients are younger. Endemic cardiomyopathies include dilated cardiomyopathy, peripartum cardiomyopathy and endomyocardial fibrosis. Nonendemic cardiomyopathies apparently occur with the same frequency as in other parts of the world, and include hypertrophic cardiomyopathy and arrhythmogenic right ventricular dysplasia/cardiomyopathy. Coronary artery disease and its complications remain uncommon in Africa, but the situation is changing due to modifications in lifestyle, risk-prone behavior, diet, cultural attitudes and other consequences of rapid urbanization. As the prevalence of heart failure is expected to rise substantially in sub-Saharan Africa, the authors call for population-based studies and registries of the epidemiology of heart failure in Africans and the urgent study of interventions that will decrease morbidity and mortality from the causes of heart failure, with a focus both on nonischemic and ischemic risk factors.

Endomyocardial fibrosis: still a mystery after 60 years

The pathologist Jack N. P. Davies identified endomyocardial fibrosis in Uganda in 1947. Since that time, reports of this restrictive cardiomyopathy have come from other parts of tropical Africa, South Asia, and South America. In Kampala, the disease accounts for 20% of heart disease patients referred for echocardiography. We conducted a systematic review of research on the epidemiology and etiology of endomyocardial fibrosis. We relied primarily on articles in the MEDLINE database with either “endomyocardial fibrosis” or “endomyocardial sclerosis” in the title. The volume of publications on endomyocardial fibrosis has declined since the 1980s. Despite several hypotheses regarding cause, no account of the etiology of this disease has yet fully explained its unique geographical distribution.

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.