Endomyocardial fibrosis

Endomyocardial fibrosis is an acquired disease of the endocardium and innermost myocardium that produces a characteristic restrictive cardiomyopathy phenotype.
The fundamental lesion is a fibrous plaque that mainly lines the apex and inflow tract of one or both ventricles, progressively reduces the available cavity, and may incorporate organized thrombus, calcifications, papillary muscles and chordae tendineae.
The heart becomes unable to accommodate blood without a rapid increase in diastolic pressure; the atria dilate, the mitral or tricuspid valve becomes regurgitant, and pulmonary congestion, systemic congestion, arrhythmias and thromboembolism develop.

The form described by Jack Davies in Uganda, known as tropical endomyocardial fibrosis or Davies disease, has historically affected children, adolescents and young adults in equatorial regions of sub-Saharan Africa, with cases and foci also in India, other Asian territories and Latin America.
It is not, however, a disease confined to the tropics: migration, travel and nontropical forms make diagnosis possible in any country, whereas in Europe and North America the same fibrothrombotic appearance should prompt particularly careful investigation for hypereosinophilic syndrome, vasculitis, a hematologic malignancy, a drug reaction or another defined cause.
Geographic distribution guides reasoning but does not replace demonstration of the disease.

Worldwide prevalence is unknown. Hospital registries, autopsy studies and echocardiographic studies have used different definitions and include populations with highly unequal access to care; moreover, some formerly endemic areas have observed a marked decline in new cases, whereas elsewhere the disease probably remains underdiagnosed.
In a door-to-door survey conducted in a specific rural area of Mozambique, echocardiography identified compatible findings in 19.8 percent of 1,063 participants, but only 22.7 percent of subjects classified as affected reported symptoms. These data are fundamental in demonstrating the existence of a subclinical phase, but they do not represent a transferable estimate for all of Mozambique, Africa or the general population.
The true frequency requires contemporary, multicenter studies based on reproducible criteria.

Tropical endomyocardial fibrosis and Löffler endocarditis should not be used as synonyms. They share a predilection for the subendocardium, a possible sequence of necrosis, thrombosis and fibrosis, and a restrictive hemodynamic outcome, but in Löffler disease eosinophil-mediated injury is documented in the setting of primary, secondary or idiopathic hypereosinophilia.
In the tropical form, eosinophilia may be absent at the time of diagnosis and has not been proven to represent the universal causal mechanism. Confusing the two conditions can lead both to unjustified immunosuppression of an inactive scar and to missing active eosinophilic disease that requires urgent treatment.
Correct diagnosis therefore integrates cardiac anatomy, inflammatory activity and etiologic investigation.

The etiology of tropical endomyocardial fibrosis remains unproven even after more than seventy-five years of research. Its focal distribution, association with poverty and food insecurity, young age at onset and temporal variations indicate that environmental and social factors probably contribute to risk, but they do not identify a single cause.
Epidemiological association, biological plausibility and causality are not equivalent. No available hypothesis alone accounts for the geographic distribution, explains cases without apparent exposure and reproduces the entire pathological picture.
A scientifically accurate page must therefore preserve uncertainty rather than turn suggestive hypotheses into facts.

Eosinophilia has been studied because many parasitic diseases are common in endemic regions and because cationic proteins released by eosinophils can damage endothelium and cardiomyocytes, activate coagulation and promote fibrosis.
In hypereosinophilic heart disease the mechanism is convincing: eosinophilic infiltration and degranulation cause subendocardial necrosis, thrombus is deposited on the injured surface, and organization of the thrombus leaves a fibrous scar. In chronic tropical fibrosis, however, peripheral eosinophilia is not constant, active tissue findings are rare, and helminth infection and eosinophilia are also common in people without heart disease.
Eosinophilic injury is therefore a proven cause of some secondary forms, not the established explanation for every case of Davies disease.

Infectious hypotheses have implicated malaria, schistosomiasis, filariasis, toxoplasmosis and many other infections, without any agent having been isolated or associated with the disease in a necessary and sufficient manner.
A parasitic infection may cause eosinophilia, malnutrition, inflammation or hemodynamic overload and may therefore act as a cofactor; treating it is important for the patient's health, but its presence does not prove that it produced the endocardial plaque.
Endomyocardial fibrosis is not contagious and there is no documented person-to-person transmission.

Diet and micronutrients have also been explored. High cassava consumption, protein deficiency, hypomagnesemia, cerium exposure and imbalances among trace elements have been proposed on the basis of geographic observations, experimental models or small studies, but results are inconsistent and do not support a specific preventive intervention.
Malnutrition can nevertheless worsen tissue repair capacity, susceptibility to infection, muscle reserve and tolerance of heart failure or surgery. It is therefore an important clinical determinant even when it is not the initiating cause.
Improvement in socioeconomic conditions may contribute to the decline observed in some regions, but this relationship remains multifactorial.

Familial clustering and immunogenetic associations have been described without identification of a monogenic gene responsible for the tropical form. An affected relative does not demonstrate Mendelian transmission because members of the same family share environment, diet, infections and access to care.
Genetic testing is therefore not a routine test to confirm typical endomyocardial fibrosis; it may become appropriate when the phenotype, family history or other signs suggest an alternative genetic cardiomyopathy.
Counseling prevents confusion between possible complex susceptibility and a causative mutation.

The classic pathogenetic model divides the history into necrotic, thrombotic and fibrotic phases. In the proposed initial phase, inflammation and possible eosinophilic infiltration damage the endocardium and inner myocardium; mural thrombus then forms, especially in apical regions with slow flow; finally, thrombus organization, fibroblast proliferation and collagen deposition produce the scar.
This sequence is clearly recognizable in eosinophilic disease and is a useful model for understanding the morphology, but the acute phase of the tropical form has rarely been observed and its universality has not been proven.
Many patients come to clinical attention directly in the irreversible fibrotic phase.

Macroscopically, fibrosis favors the apices and extends along the walls toward the inflow tracts, whereas the outflow tracts are relatively spared. The endocardial surface becomes whitish, smooth or irregular and may contain layered thrombus and calcifications.
The lesion may be exclusively right-sided, exclusively left-sided or biventricular. The proportions differ among cohorts and there is no universal distribution; the biventricular form is common and generally more severe.
Recognition of the location is essential because it determines symptoms, echocardiographic findings and the operative strategy.

Histologically, dense collagen and fibroelastic tissue predominate, with variable extension into the subendocardium and inner myocardium. The boundary between plaque and myocardium may be sharp or may show interstitial fibrosis, newly formed vessels, small inflammatory infiltrates and foci of calcification.
A biopsy sample may capture only nonspecific tissue or uninvolved myocardium because the distribution is irregular and the obliterated apex is difficult and risky to sample.
Pathology remains valuable, but a negative result does not automatically exclude the disease.

Apical obliteration reduces end-diastolic volume and makes the cavity poorly compliant. Even a small amount of incoming blood requires a large rise in pressure, with rapid early ventricular filling followed by abrupt cessation: this is the basis of restrictive physiology.
Ejection fraction may remain apparently normal because it expresses a proportion of an already reduced volume; absolute stroke volume may instead be low. Tachycardia, fever, anemia or pregnancy further shorten diastole and can precipitate symptoms.
A preserved ejection fraction therefore does not mean normal cardiac function.

When fibrosis incorporates papillary muscles, chordae or walls near the valve, it limits leaflet motion and alters coaptation. The result is mitral regurgitation in the left-sided form and tricuspid regurgitation in the right-sided form, adding atrial volume overload to ventricular restriction.
Annular dilation secondary to atrial enlargement can amplify regurgitation. Valvular disease is therefore neither a coincidence nor a primary leaflet disorder, but an integral part of endomyocardial remodeling.
Its correction also requires release of the subvalvular apparatus when technically possible.

Chronic elevation of atrial pressure produces markedly dilated atria. On the left it causes pulmonary venous congestion, reduced lung compliance and subsequent pulmonary hypertension; on the right it causes jugular venous distention, hepatic congestion, ascites and edema.
The dilated and fibrotic atrium also provides a substrate for atrial fibrillation and flutter. Loss of atrial contraction is particularly poorly tolerated by a stiff ventricle, in which the atrial contribution to filling may be crucial.
The arrhythmia can therefore transform a compensated condition into low-output heart failure.

Mural thrombus and atrial stasis create a risk of embolism. In the left ventricle, a fragment may reach the brain, kidneys, spleen or limbs; in the right ventricle it may cause pulmonary embolism, although distinguishing thrombus from fibrous plaque is not always straightforward on imaging.
Organized thrombus can become part of the endocardial mass and contribute to progressive obliteration. This relationship does not mean that every fibrotic surface requires indefinite anticoagulation, but it mandates systematic assessment for thrombi and an individualized judgment of risk.
Magnetic resonance is particularly useful for separating vascularized tissue from avascular material.

Presentation varies with age, rate of progression, the ventricle involved, severity of valvular regurgitation and nutritional status. Early forms identified by echocardiographic screening may be asymptomatic or cause only reduced exercise endurance, whereas hospital series predominantly describe advanced disease.
Dyspnea, fatigue, palpitations, edema and abdominal distention are nonspecific; they become informative when associated with signs of restriction, dilated atria and apical obliteration.
The absence of severe symptoms does not exclude a significant structural lesion.

The history should reconstruct place of birth, residences, travel, parasite exposures, quality of nutrition, infections, allergies, asthma, rash, medications and substances. Fever, weight loss, sweating, neuropathy, sinusitis, purpura or respiratory symptoms may indicate an alternative inflammatory, vasculitic, infectious or neoplastic cause.
Onset and progression of dyspnea, orthopnea, nocturnal episodes, syncope, chest pain, palpitations, increasing abdominal girth, edema and neurological events should be defined precisely.
A previous eosinophil count, even if normal today, can radically change the diagnostic framework.

The predominantly right-sided form mainly produces systemic congestion. The patient reports abdominal fullness, early satiety, nausea, fluid-related weight gain, pain or heaviness in the right upper quadrant, dependent edema and reduced walking capacity.
Ascites may be very marked and apparently disproportionate to peripheral edema; high venous pressures, tricuspid regurgitation, reduced lymphatic drainage, hepatic abnormalities and hypoalbuminemia all contribute. Isolated ascites, however, should not lead to automatic attribution of the condition to the liver.
Simultaneous assessment of the jugular veins, heart, liver and vena cava points toward a cardiac origin.

On examination in the right-sided form, the jugular veins are distended, with a prominent v wave if tricuspid regurgitation is significant. The liver may be enlarged and pulsatile, the abdomen tense from ascites and the limbs edematous; a parasternal impulse may indicate right-sided overload or pulmonary hypertension.
The holosystolic tricuspid murmur tends to increase with inspiration but may be subtle when output is very low. Additional heart sounds, pericardial effusion and hypotension sometimes complete the picture.
Central cyanosis requires investigation for a right-to-left shunt or severe low cardiac output.

The predominantly left-sided form presents with exertional dyspnea, orthopnea, nocturnal cough, episodes of pulmonary edema and reduced activity tolerance. Mitral regurgitation may cause palpitations, pulmonary congestion and an apical holosystolic murmur, sometimes attenuated by low output.
Pulmonary crackles, tachypnea and reduced oxygen saturation appear during exacerbations. Blood pressure may remain normal initially and fall when stroke volume is no longer sufficient.
Thrombi in the left ventricle or dilated atrium may present with stroke or peripheral ischemia before overt heart failure.

Biventricular involvement combines pulmonary and systemic congestion and has the least hemodynamic reserve. Dyspnea, ascites, edema, hepatomegaly and hypoperfusion coexist; the patient may lose muscle mass despite fluid-related weight gain.
Elevated pulmonary pressure worsens right ventricular load, whereas regurgitation of both valves multiplies atrial overload. At this stage, renal and liver function become sensitive to minimal changes in output and diuretic therapy.
Multiorgan frailty also increases the risk of surgical correction.

Atrial fibrillation and flutter are favored by marked atrial dilation. The patient may experience an irregular heartbeat, sudden breathlessness, dizziness or worsening ascites; sometimes the arrhythmia is silent and discovered on electrocardiography.
A very high rate reduces filling time, whereas an excessively low rate cannot be compensated by an increase in stroke volume from the stiff ventricle. Control must therefore avoid both extremes.
Restoration of sinus rhythm is desirable in many patients, but massively dilated atria make recurrence common.

Ventricular arrhythmias, conduction blocks and sudden death have been described, but their specific frequency is difficult to quantify because of the paucity of modern cohorts. Exertional syncope, sustained palpitations, a history of cardiac arrest or ventricular dysfunction require urgent assessment.
Scar may provide a reentry substrate, whereas electrolyte abnormalities, medications and low output act as triggers. However, there is no sudden death risk calculator validated specifically for endomyocardial fibrosis.
Decisions about monitoring and devices should follow the individual profile and appropriate general indications.

In children, poor growth, delayed puberty, a protuberant abdomen from ascites, recurrent infections, weakness and reduced participation in play may predominate. Malnutrition may be a contextual factor, a consequence of intestinal congestion and early satiety, or both.
A murmur may initially be attributed to rheumatic heart disease, an important cause in the same regions; imaging must distinguish primary leaflet disease from tethering secondary to fibrosis.
Diagnostic delay allows hepatic injury, pulmonary hypertension and cachexia to become less reversible.

An early febrile phase with pruritus, facial edema, acute dyspnea, chest pain and eosinophilia has been reported in historical models but is rarely observed in established tropical fibrosis. When present, it should not automatically be labeled a prodrome of Davies disease.
Eosinophilic myocarditis, hypereosinophilic syndrome, drug reaction, parasitic infection, eosinophilic granulomatosis with polyangiitis and hematologic malignancy must be excluded. These conditions have their own criteria and treatments.
Evidence of inflammatory activity may make part of the injury reversible and changes therapeutic urgency.

Functional status should be described through concrete activities in addition to New York Heart Association class. Walking distance, number of stairs, ability to work, frequency of hospitalizations, urine output, appetite and need for paracentesis better measure the real impact.
Weight, abdominal circumference and venous pressure help track congestion, whereas strength and body composition distinguish muscle loss from fluid changes. Cardiopulmonary exercise testing can quantify limitation in selected stable patients.
These data are also useful for deciding the timing and risk of intervention.

Warning signs are dyspnea at rest, pulmonary edema, syncope, persistent chest pain, sudden neurological deficit, a cold painful limb, hemoptysis, hypotension, oliguria and rapidly increasing ascites. They require urgent assessment because they may indicate acute heart failure, arrhythmia, embolism, ischemia, infection or organ failure.
A patient with restrictive physiology may deteriorate rapidly after dehydration, bleeding, fever, diarrhea or excessive doses of diuretics. Even an apparent reduction in edema may accompany a dangerous fall in cardiac output.
Clinical assessment must therefore integrate congestion and perfusion.

Diagnosis arises from concordance among endocardial morphology, restrictive physiology and clinical context. There is no specific blood biomarker and no single international criterion capable of confirming every tropical, eosinophilic, right-sided, left-sided, early or calcific form.
The diagnostic workup must answer four questions: is the cavity truly obliterated by endocardial tissue, which ventricle and which valve are involved, are thrombus or inflammatory activity present, and is there an alternative or treatable cause?
The anatomical diagnosis and the etiologic diagnosis are related but do not coincide.

Initial tests include a complete blood count with differential and absolute eosinophil count, electrolytes, creatinine, liver function, albumin, urinalysis and, according to presentation, troponin and natriuretic peptides. Anemia, hypoalbuminemia, renal and liver dysfunction measure severity and modify treatment but are not diagnostic.
A normal eosinophil count does not exclude a previous eosinophilic phase or chronic tropical fibrosis. An elevated count should be confirmed, quantified over time and explained, not simply attributed to the heart.
A peripheral blood smear and hematology consultation become necessary when clonal proliferation is suspected.

The etiologic investigation of eosinophilia is guided by exposures and organs involved. It may include parasitological and serological tests appropriate to geography, medication review, immunologic testing for vasculitis, tryptase and vitamin B12, flow cytometry, bone marrow examination and molecular testing for clonal rearrangements when indicated.
Empirical corticosteroid administration before excluding some parasitic infections, especially strongyloidiasis, can be dangerous. On the other hand, threatening eosinophilic cardiac injury may require treatment before the entire workup is complete.
Priority should be decided with a cardiologist, hematologist, infectious disease specialist and rheumatologist.

The electrocardiogram may show sinus rhythm with nonspecific ST-T changes, low voltage, signs of atrial enlargement, bundle branch block, atrioventricular conduction disorders, or atrial fibrillation and flutter. In the right-sided form, prominent P waves and abnormalities compatible with right-sided overload may appear, without a pathognomonic pattern.
A normal ECG does not exclude structural disease. Holter or prolonged monitoring is indicated in the presence of palpitations, syncope, markedly dilated atria, known arrhythmias or suspected electrical instability.
The frequency, duration and context of arrhythmias guide anticoagulation and treatment.

Chest radiography may show cardiomegaly, especially atrial enlargement, pulmonary congestion, pleural effusion or apical calcifications. In isolated right-sided disease, the right cardiac silhouette may be greatly enlarged with relatively clear lung fields; in left-sided disease, signs of pulmonary venous hypertension predominate.
The absence of marked cardiomegaly is compatible with a small ventricular cavity and does not exclude severe heart failure. Computed tomography better defines calcifications, the pericardium, coronary anatomy and preoperative relationships when necessary.
Neither examination replaces echocardiography.

In the diagnostic pathway, transthoracic echocardiography is the fundamental initial examination because it is accessible, repeatable and capable of simultaneously assessing anatomy, hemodynamics and valves. The most characteristic finding is apical endocardial thickening with partial or complete obliteration, which shortens the ventricle and deforms the normal apex.
The cavity is normal or reduced, the atria are dilated, and the mitral or tricuspid apparatus may be adherent to the wall. It is essential to optimize views and use echocardiographic contrast if the endocardial border is not readable.
An apex that is not visualized should not be declared obliterated.

In right-sided disease, retraction or obliteration of the apex, right atrial dilation, tricuspid regurgitation, a dilated vena cava and sometimes pericardial effusion are observed. The ventricle may acquire a configuration described as the mushroom sign, but this is a morphological description and not a sufficient isolated criterion.
Estimated pulmonary pressure, right ventricular longitudinal function and residual cavity area help define severity. In severe tricuspid regurgitation, a low jet velocity does not exclude very high atrial pressure.
Integration with hepatic venous flow and systemic signs prevents errors.

In left-sided disease, echocardiography shows apical obliteration, fibrosis of the inflow tract, adherence of the posterior mitral leaflet, mitral regurgitation and a large left atrium. Doppler may document restrictive filling with a dominant E wave, short deceleration time and abnormalities of pulmonary venous flow, but these parameters depend on rhythm, volume and pressure.
Global systolic function may appear preserved; longitudinal strain, stroke volume and cardiac output often reveal impairment not expressed by ejection fraction alone. Apical thrombus appears as a mass and must be distinguished from plaque, tumor and hypertrophied myocardium.
Contrast and magnetic resonance resolve many uncertain cases.

The echocardiographic criteria proposed by Mocumbi in the Mozambique population study include major and minor signs and consider a combination of two major criteria or one major and two minor criteria compatible with the diagnosis. The severity score reaches 35 points, with mild disease up to 8, moderate disease from 9 to 15, and severe disease from 16 onward.
The elements considered include endomyocardial plaques, apical obliteration, thrombus without severe ventricular dysfunction, retraction of the right ventricular apex, adherence of the atrioventricular apparatus, atrial dilation and restrictive filling. The system enabled comparison and screening in an endemic setting.
It is not, however, a universal official criterion and does not replace assessment for alternative diagnoses in different populations.

Cardiac magnetic resonance confirms the distribution and thickness of the lesion, measures the volumes and function of both ventricles, and characterizes tissue. The typical pattern is subendocardial late gadolinium enhancement that is not confined to the territory of a coronary artery, often apical and associated with cavity obliteration.
Cine sequences show valvular tethering; early and late acquisitions help distinguish avascular thrombus, which does not enhance, from fibrosis and myocardium. Edema or elevated T2 signals may support inflammatory activity but are nonspecific and must be interpreted in context.
The amount of fibrosis also provides prognostic and preoperative information.

The differential diagnosis with apical hypertrophic cardiomyopathy is common: in hypertrophy, the mass narrowing the apex is thickened, contractile myocardium, whereas in fibrosis the dominant findings are endocardial plaque, thrombus, subendocardial enhancement and involvement of the valvular apparatus.
Amyloidosis produces wall thickening and restriction but has a different tissue distribution, extracardiac signs and magnetic resonance pattern. Storage cardiomyopathy, sarcoidosis and genetic diseases require targeted testing.
Subendocardial late enhancement from infarction instead follows a coronary distribution and is accompanied by the appropriate ischemic history.

Constrictive pericarditis mimics restriction with ascites, distended jugular veins and relatively preserved systolic function. In endomyocardial disease the problem is inside the cavity; in constriction the pericardium limits filling, producing respiratory ventricular interdependence, characteristic septal motion and respiratory variation of flows.
Computed tomography and magnetic resonance assess pericardial thickening and calcification, but a pericardium of normal thickness does not exclude constriction. In discordant cases, simultaneous ventricular catheterization analyzes the respiratory response of pressures.
The distinction is decisive because the surgical strategy is completely different.

Cardiac carcinoid disease, rheumatic heart disease, Ebstein anomaly and functional regurgitation can mimic the right-sided or valvular form. Carcinoid predominantly thickens the leaflets and chordae of the right-sided valves in a specific systemic context, whereas endomyocardial fibrosis begins on the ventricular surface and entraps the apparatus.
Endocarditis, tumors, isolated thrombi and calcifications sometimes require transesophageal echocardiography, computed tomography or metabolic imaging. Noncompaction and prominent trabeculations may be concealed or mimicked by apical material.
Review of the images at an expert center reduces erroneous diagnoses and interventions.

Cardiac catheterization is not necessary when echocardiography and magnetic resonance are concordant, but it can measure pressures and resistances, clarify discrepancies with constriction and define operability. The ventricular pressure curve shows rapid early filling followed by a plateau, elevated end-diastolic pressures and possible equalization; ventriculography shows obliteration and regurgitation.
Coronary angiography or CT angiography is selected according to age, ischemic risk and surgical planning. Every intracavitary procedure must consider the small apex, thrombus and the risk of perforation or embolism.
The result should have an anticipated clinical consequence.

Endomyocardial biopsy is reserved for cases in which imaging and laboratory findings suggest inflammation, infiltration or storage that cannot otherwise be identified and in which the result may change treatment. It may demonstrate fibrosis, organized thrombus, calcification or eosinophilic infiltrate, but septal sampling may not reach the apical lesion.
Biopsy of an obliterated cavity carries risks and a nonspecific scar does not necessarily reveal the cause. In patients undergoing endocardectomy, surgical tissue provides a much broader assessment and should be studied with histology, staining and appropriate etiologic investigations.
Biopsy is not a mandatory step for every typical diagnosis.

The final diagnosis should specify the side involved, extent of fibrosis, degree of obliteration, diastolic physiology, biventricular function, the valve involved and severity of regurgitation, presence of thrombus, rhythm, pulmonary pressure and possible cause. A formulation such as severe biventricular endomyocardial fibrosis with apical obliteration, severe tricuspid regurgitation and left-sided thrombus communicates more than the label alone.
The degree of certainty and unresolved questions should also be stated, for example unproven eosinophilic activity or incomplete distinction from constriction. Serial reassessment documents progression and response to treatment.
A structured report becomes the basis for multidisciplinary discussion.

For chronic tropical endomyocardial fibrosis, there is no pharmacological therapy capable of dissolving the scar or reliably modifying the natural history. The goals are to relieve congestion, preserve perfusion and nutrition, prevent thromboembolism, treat arrhythmias and valvular disease, identify any active cause, and promptly select surgical candidates.
Evidence comes mainly from observational cohorts, small surgical series and principles applied to restrictive cardiomyopathies; large disease-specific randomized trials are lacking.
Every recommendation must therefore be adapted to the patient's anatomy, available resources and preferences.

Loop diuretics reduce pulmonary edema, ascites and peripheral congestion; a mineralocorticoid receptor antagonist may be added with monitoring of potassium and renal function. The effective dose is the one that achieves euvolemia without excessively depleting the circulation.
The stiff ventricle is preload-dependent and cannot substantially increase stroke volume: aggressive diuresis can cause hypotension, renal failure and low output. Weight, blood pressure, urine output, creatinine, electrolytes, jugular veins and edema guide dose changes.
Salt restriction should be individualized while avoiding worsening malnutrition.

ACE inhibitors, angiotensin receptor blockers, beta-blockers and other drugs with proven benefit in heart failure with reduced ejection fraction do not have disease-specific prognostic evidence in endomyocardial fibrosis with restrictive physiology and preserved ejection fraction. They may be indicated for hypertension, systolic dysfunction, ischemia or another comorbidity, but hypotension and fixed cardiac output often limit tolerance.
Beta-blockers may help rate control, but marked bradycardia reduces cardiac output in patients who cannot increase stroke volume. Vasodilators and inotropic drugs require the same hemodynamic caution.
Prescribing should follow the actual phenotype, not a diagnostic automatism.

Atrial fibrillation and flutter require correction of electrolytes, congestion and precipitating factors, followed by a choice between rhythm and rate control. Maintaining sinus rhythm is physiologically advantageous, but cardioversion and antiarrhythmic drugs are less successful when the atria are massively dilated and pressure remains elevated.
Drug safety depends on ventricular function, renal and liver function and QT interval. Catheter ablation may be considered in selected cases, explaining that advanced atrial substrate increases recurrence.
Symptomatic bradycardia or block may make a pacemaker necessary.

Anticoagulation is indicated in the presence of intracardiac thrombus, previous embolism, atrial fibrillation with an appropriate risk profile, or another high-risk condition. Massive atrial dilation and stasis may suggest a risk greater than that expressed by conventional scores, but there is no evidence that every patient with fibrosis should receive lifelong anticoagulation.
Drug choice and dose take into account prosthetic valves, renal and liver function, interactions, pregnancy, availability of monitoring and bleeding risk. Disease-specific data on direct oral anticoagulants in endomyocardial fibrosis are scarce.
Serial imaging assesses thrombus evolution without replacing clinical evaluation.

Tense ascites may require therapeutic paracentesis when it compromises breathing, nutrition or renal function, together with correction of cardiac congestion. Removal of large volumes changes preload and should be planned with hemodynamic monitoring and assessment of albumin according to the clinical situation.
Repeated paracentesis without control of the underlying cause promotes protein loss, infection and worsening nutritional status. Nutritional support should provide adequate energy and protein compatible with liver and renal function and intestinal tolerance.
Gradual rehabilitation counteracts sarcopenia without imposing unsustainable exertion.

If active eosinophilic disease is demonstrated, treatment is not that of the tropical scar alone. Corticosteroids may be urgently required in eosinophilic organ injury, whereas parasitic infections, drug reactions, vasculitides and neoplasms require distinct causal treatments; tyrosine kinase rearrangements such as FIP1L1-PDGFRA may respond to targeted hematologic therapy.
These drugs should not be prescribed empirically to a patient with inactive tropical fibrosis solely because of anatomical similarity. The risk of latent or parasitic infections should be considered before immunosuppression.
The goal in the active phase is to halt injury before thrombus and fibrosis become irreversible.

Traditional surgery combines endocardectomy or plaque decortication, reopening of the apex and release of the subvalvular apparatus with mitral or tricuspid repair or replacement. The goal is not to remove every micron of tissue but to increase useful volume, reduce filling pressures and restore valve competence without perforating a thinned wall.
Reconstruction may involve one or both ventricles and requires detailed imaging. Preserving the valve avoids a prosthesis when geometry permits; replacement is necessary if the leaflets and apparatus are irreversibly involved.
Surgical technique and center experience substantially influence the result.

Surgical assessment is reasonable in patients with advanced functional limitation, severe restriction or regurgitation and persistent symptoms despite medical therapy, provided anatomy and general condition offer a realistic possibility of benefit. Waiting for irreversible liver injury, fixed pulmonary hypertension, cachexia or terminal right ventricular dysfunction may make the operation prohibitive.
Conversely, operating on mild stable disease exposes the patient to unjustified risk. The decision integrates symptoms, hospitalizations, hemodynamics, magnetic resonance extent, residual volume, valves, thrombi, nutrition and organ function.
There is no universal numerical threshold valid for every center and phenotype.

Risks include bleeding, ventricular perforation, coronary injury, embolism, atrioventricular block, arrhythmias, right-sided failure and low-output syndrome. Historical series report considerable operative mortality, but they reflect different eras, techniques and preoperative severity and do not support a single contemporary percentage.
Residual fibrosis may continue to limit filling; disease may recur or appear in the contralateral ventricle, and a repaired or replaced valve may require reintervention. Surgery should therefore be presented as a potentially effective mechanical treatment, not as a guarantee of biological cure.
Follow-up remains lifelong even after a good result.

Long-term observations show that selected patients can achieve lower filling pressures, greater useful ventricular volume and improved functional class. In a small Zurich series, survival among operated patients was approximately 72 percent at five years and 68 percent at ten years; in a Brazilian series of 83 operations, actuarial survival at seventeen years, including operative mortality, was 55 percent.
These figures do not represent an individual prediction: they come from selected cohorts treated in different periods and without randomization. They demonstrate both the possibility of benefit and residual risk.
Comparison with medical therapy alone is subject to strong selection bias.

Heart transplantation may be considered in advanced uncorrectable heart failure in the absence of systemic contraindications, but small cavities, pulmonary hypertension, malnutrition, infections and organ injury complicate selection. Ventricular assist devices are technically difficult when the apex is obliterated and space for the inflow cannula is limited.
Disease-specific experience is limited and availability is minimal in regions with the greatest disease burden. Early palliative care does not mean abandonment: it addresses dyspnea, ascites, pain, anxiety and care goals alongside cardiological treatments.
Advance planning is particularly useful in inoperable patients.

Prognosis is poor in untreated advanced disease but cannot be summarized by a single survival figure. Biventricular involvement, functional class III or IV, atrial fibrillation, severe atrioventricular regurgitation, elevated pulmonary pressure, right ventricular dysfunction, low output, refractory ascites and renal or liver injury indicate higher risk.
The extent of fibrosis and thrombus on magnetic resonance and repeated hospitalizations add information. Univentricular disease recognized before multiorgan injury may have a more favorable course, especially if it is correctable.
Periodic reassessment should update risk rather than focus only on ejection fraction.

Follow-up includes symptoms, functional class, weight, blood pressure, rhythm, renal and liver function, electrolytes, echocardiography and treatment adherence. Holter monitoring and magnetic resonance are repeated when arrhythmias, progression, thrombus or surgical planning require them; there is no identical interval for everyone.
After surgery, chamber volume, residual or recurrent fibrosis, valve function, prostheses, conduction and anticoagulation are monitored. Vaccinations, dental health and endocarditis prophylaxis follow the type of prosthesis and current indications, not fibrosis itself.
A shared pathway between an expert center and local care reduces delays and fragmentation.

Heart failure is the dominant complication and results from the combination of reduced cavity size, diastolic stiffness, valvular regurgitation and, in advanced stages, systolic dysfunction. It may be predominantly right-sided, left-sided or biventricular and alternates relatively stable periods with exacerbations triggered by arrhythmias, infections, anemia, pregnancy, excess salt, interruption of medications or abrupt volume changes.
Pressure may be elevated because of congestion while cardiac output is simultaneously inadequate. Treating edema alone without assessing perfusion exposes the patient to renal failure and shock.
Every exacerbation should prompt a search for the precipitating factor in addition to increasing diuretics.

In the left-sided form, high atrial pressures cause interstitial and alveolar edema, hypoxemia, pleural effusions and postcapillary pulmonary hypertension. Repeated episodes remodel the pulmonary circulation and increase right ventricular load, transforming initially left-sided disease into functional biventricular failure.
Severe mitral regurgitation accelerates the process and promotes atrial fibrillation. Hemoptysis and chest pain also require exclusion of pulmonary embolism, infection and ischemia.
Oxygen corrects hypoxemia but does not resolve filling pressures.

In the right-sided form, chronic venous congestion causes hepatomegaly, cholestasis, congestive hepatic fibrosis, ascites, intestinal edema, malabsorption and deterioration of renal function. A pulsatile liver often reflects severe tricuspid regurgitation; in late stages, coagulopathy and hypoalbuminemia increase bleeding risk and edema.
Creatinine may worsen because of either renal congestion or low perfusion. Decongestion may initially change values without necessarily indicating structural injury, but requires close monitoring.
Organ function determines operability and prognosis.

Refractory ascites compresses the diaphragm and stomach, causing dyspnea, early satiety and muscle loss. Repeated paracentesis exposes the patient to hypotension, protein loss, bleeding and infection; indwelling catheters carry additional risks and require clear palliative goals.
It is important to distinguish cardiac congestion, primary cirrhosis, peritoneal tuberculosis, malignancy and other causes that may coexist in endemic areas. Fluid analysis, hepatic imaging and hemodynamic profiling are selected according to the clinical question.
Attributing every case of ascites to the heart may delay a second treatable diagnosis.

Intracardiac thrombus may form on the injured endocardial surface, in the obliterated apex or in dilated atria. Left-sided consequences include stroke, transient ischemic attack, mesenteric, renal, splenic or limb ischemia; right-sided consequences include pulmonary embolism and possible chronic thromboembolic pulmonary hypertension.
An embolic event may occur even without documented atrial fibrillation. Conversely, an apical mass is not always a thrombus, and anticoagulating it without characterization may delay the diagnosis of plaque, calcification or tumor.
Echocardiographic contrast, magnetic resonance and follow-up of the response reduce uncertainty.

Atrial fibrillation and flutter worsen cardiac output, increase congestion and embolic risk, and may cause tachycardia-induced cardiomyopathy. Cardioversion without adequate exclusion of atrial thrombus exposes the patient to embolism, whereas excessive rate control causes bradycardia and hypoperfusion.
Antiarrhythmic drugs may prolong the QT interval, interact with anticoagulants or accumulate in hepatic and renal failure. Ablation may cause tamponade, venous stenosis or recurrence and should be reserved for proportionate indications.
Management requires a balance among rhythm, cardiac output and thromboembolic safety.

Ventricular scar may sustain ventricular tachycardia, whereas diuretic-induced hypokalemia and hypomagnesemia facilitate its initiation. Arrhythmic syncope, sustained tachycardia and cardiac arrest require assessment for a defibrillator according to general indications because no specific validated algorithm exists for this disease.
A device does not correct low output or heart failure and may cause infection, inappropriate shocks or lead problems. The decision should consider life expectancy, surgical options and access to follow-up.
Correction of electrolyte abnormalities is a simple but essential measure.

Conduction disorders may result from extension of fibrosis or surgical injury near the atrioventricular conduction system. Advanced block and symptomatic bradycardia require pacing; after endocardectomy, monitoring identifies transient or permanent block early.
The pacemaker must also be programmed with attention to the need for atrioventricular synchrony and the dependence of cardiac output on heart rate. Long-term nonphysiological ventricular pacing may worsen function in some patients.
Pacing mode and site are individualized according to anatomy and rhythm.

Mitral and tricuspid regurgitation may become hemodynamically dominant. Regurgitation drives atrial dilation, fibrillation, congestion and ventricular dysfunction, but isolated correction without addressing the plaque and tethering may not restore filling.
Mechanical prostheses require lifelong anticoagulation and carry thrombotic or bleeding risk; bioprostheses may degenerate, especially in young patients. Repair may fail again if annular dilation and fibrosis progress.
The technical choice should consider age, pregnancy, access to monitoring and the likelihood of reintervention.

Advanced pulmonary hypertension and right ventricular dysfunction increase the risk of syncope, liver failure, arrhythmias and operative mortality. Drugs specific for pulmonary arterial hypertension should not be prescribed automatically when pressure elevation results from high left-sided pressures because they may increase flow toward a congested left atrium.
Right heart catheterization is useful when the mechanism is unclear or when an advanced decision depends on resistance and reversibility. Oxygen, treatment of congestion and valve correction address the most common pathophysiology.
Therapy follows the demonstrated hemodynamic group, not the echocardiographic pressure value alone.

Pericardial effusion is common, especially with right-sided congestion, and is usually small; a large effusion or one with signs of tamponade requires investigation for infection, malignancy, hypothyroidism, renal failure or concomitant inflammation. Tamponade physiology may be atypical when right-sided pressures are already very high.
Endomyocardial calcification may be extensive, further stiffen the wall and complicate surgical resection. Computed tomography and magnetic resonance define its relationship to the coronary arteries and myocardial thickness.
The pericardium and endocardium should be assessed separately even when abnormalities coexist.

Cardiac cachexia results from early satiety, intestinal congestion, inflammation, increased energy expenditure and reduced intake. In children it impairs growth and development; in adults it reduces strength, immunity, wound healing and tolerance of surgery.
Body weight may conceal it because ascites and edema add kilograms while muscle is lost. Arm circumference, handgrip strength, albumin interpreted in context and dietetic assessment better describe risk.
Nutritional recovery is part of treatment, not an ancillary intervention.

Pregnancy increases plasma volume and heart rate and may decompensate previously tolerated restrictive physiology. Anticoagulants, diuretics and antiarrhythmic drugs have different fetal safety profiles; severe regurgitation, pulmonary hypertension and ventricular dysfunction increase maternal risk.
Preconception counseling at a cardio-obstetric center allows individualized risk estimation, medication review and a surveillance plan. An established pregnancy requires multidisciplinary management, not independent discontinuation of therapy.
The tropical form does not in itself imply hereditary transmission to the fetus.

Iatrogenic complications include volume depletion, electrolyte disturbances, renal injury, anticoagulant-related bleeding, antiarrhythmic toxicity, device infection and complications of catheterization, biopsy, paracentesis or surgery. Risk increases when follow-up and laboratory monitoring are difficult.
Prevention means using each intervention for a precise indication, establishing in advance which monitoring will ensure safety, and promptly recognizing adverse effects. Polypharmacy should be reviewed after every hospitalization or change in organ function.
A potentially useful treatment becomes dangerous if it cannot be monitored.

Recurrence after endocardectomy and progression in the initially spared ventricle are documented late complications. Worsening dyspnea, ascites, murmur or arrhythmias after a period of benefit requires repeat echocardiography and comparison with previous images, without attributing everything to the prosthesis or treatment adherence.
Residual fibrosis, new plaque, valvular regurgitation, thrombus and ventricular dysfunction may coexist. Reoperation is possible in selected cases but carries higher risk and should be discussed at an expert center.
Lifelong surveillance is therefore an integral part of surgical treatment.

Psychological and social consequences include loss of schooling or work, dependence on family, anxiety about arrhythmias and emboli, and difficulty accessing imaging, anticoagulation and cardiac surgery. In endemic areas, the cost of travel can be as real a complication as a drug adverse effect because it interrupts follow-up and delays heart failure management.
Education about warning signs, a written medication plan, local contacts and coordination among specialists reduce risk. Psychological support and palliative care can accompany active treatment at any stage.
Quality of life is an essential clinical outcome, not a secondary parameter.