What type of cardiomyopathy is most likely in a 55-year-old male with hepatic (liver) and abdominal distention, exertional intolerance, early fluid retention, and dominant right-sided symptoms?

Restrictive Cardiomyopathy (Answer: B)

The clinical presentation of hepatic and abdominal distention, exertional intolerance, early fluid retention, and dominant right-sided symptoms in a 55-year-old male is most consistent with restrictive cardiomyopathy. 1, 2, 3

Clinical Reasoning

Why Restrictive Cardiomyopathy Fits This Presentation

Restrictive cardiomyopathy characteristically presents with prominent right-sided heart failure symptoms early in the disease course. 1, 2, 3 The key distinguishing features in this patient include:

• Hepatic congestion and abdominal distention (ascites) are hallmark manifestations of restrictive cardiomyopathy due to elevated right-sided filling pressures causing systemic venous congestion 1, 2, 3

• Early and prominent fluid retention occurs because restrictive physiology causes severe diastolic dysfunction with elevated filling pressures, leading to backward congestion into the systemic circulation 2, 4, 3

• Dominant right-sided symptoms including peripheral edema, hepatomegaly, and ascites are characteristic, as restrictive cardiomyopathy often presents with evidence of right heart failure (elevated central venous pressure, hepatomegaly, dependent edema) 1, 2, 3

• Exertional intolerance results from impaired diastolic filling and reduced cardiac output despite often preserved systolic function in early stages 4, 5

Why Other Options Are Less Likely

Dilated cardiomyopathy (Option A) typically presents with:

• Predominantly left-sided symptoms initially, including dyspnea, orthopnea, and pulmonary congestion 1
• Biventricular enlargement with systolic dysfunction as the primary abnormality 1
• Pulmonary rales and pulmonary edema are more prominent than peripheral edema in early stages 1, 6

Hypertrophic cardiomyopathy (Option C) characteristically shows:

• Massive ventricular hypertrophy with impaired diastolic function but different hemodynamic profile 7
• Tendency for sudden death and outflow tract obstruction rather than prominent fluid retention 7
• Less commonly presents with dominant right-sided failure symptoms 7

Ischemic cardiomyopathy (Option D) presents with:

• History of coronary artery disease or myocardial infarction 1
• Predominantly left ventricular systolic dysfunction with regional wall motion abnormalities 1
• Pulmonary congestion typically precedes systemic congestion 1, 6

Diagnostic Approach

Initial Clinical Assessment

Physical examination findings that support restrictive cardiomyopathy include: 1, 2, 3

• Elevated jugular venous pressure with prominent V waves
• Hepatomegaly with hepatojugular reflux
• Ascites and peripheral edema
• Kussmaul's sign (paradoxical rise in JVP with inspiration)
• S3 or S4 gallop sounds

Essential Diagnostic Testing

Echocardiography is the initial imaging test of choice and will demonstrate: 1, 4

• Preserved or near-normal left ventricular systolic function (ejection fraction often >50%)
• Biatrial enlargement disproportionate to ventricular size
• Restrictive mitral inflow pattern with high E wave velocity, short deceleration time, and low A wave 1
• Elevated E/e' ratio indicating elevated filling pressures 1
• Relative apical sparing of longitudinal strain (ratio ≥1.0) suggests cardiac amyloidosis specifically 1

Cardiac MRI provides additional diagnostic information: 1

• Diffuse subendocardial or transmural late gadolinium enhancement
• Elevated native T1 values and extracellular volume fraction
• Helps differentiate from constrictive pericarditis 1

Critical Differential Diagnosis

Distinguishing restrictive cardiomyopathy from constrictive pericarditis is essential because constrictive pericarditis is surgically treatable: 3, 5

• Cardiac catheterization may be required to demonstrate ventricular interdependence and equalization of diastolic pressures
• CT or MRI can identify pericardial thickening in constrictive pericarditis 3
• Tissue Doppler shows reduced mitral annular velocities in restrictive cardiomyopathy but preserved velocities in constriction 3

Common Etiologies to Consider

The most common causes of restrictive cardiomyopathy in this age group include: 1, 4, 5

• Cardiac amyloidosis (particularly transthyretin amyloidosis in men >50 years) - screen with technetium pyrophosphate (PYP) scan and serum/urine protein electrophoresis 1
• Infiltrative diseases including sarcoidosis, hemochromatosis 4, 5
• Endomyocardial fibrosis or hypereosinophilic syndrome 4, 7
• Post-radiation if history of chest radiation 4, 5

Clinical Pitfalls

Common diagnostic errors to avoid: 2, 3, 5

• Assuming all heart failure with edema is dilated cardiomyopathy - restrictive cardiomyopathy can present with severe peripheral edema despite preserved ejection fraction 2, 3

• Missing the diagnosis because chest X-ray appears normal - restrictive cardiomyopathy may not show cardiomegaly, especially early in disease 6, 4

• Aggressive diuresis causing hypotension - patients with restrictive physiology are preload-dependent; excessive diuresis reduces stroke volume and cardiac output significantly 5

• Failing to distinguish from constrictive pericarditis - this distinction is critical as pericardiectomy can be curative for constriction but harmful in restrictive cardiomyopathy 3, 5