Restrictive Cardiomyopathy (Answer: B)
The clinical presentation of hepatic and abdominal distention, early fluid retention, exertional intolerance, and dominant right-sided symptoms in this 55-year-old male is most consistent with restrictive cardiomyopathy. 1
Clinical Reasoning
The key distinguishing features in this case point definitively toward restrictive cardiomyopathy:
- Prominent right-sided heart failure symptoms early in the disease course are characteristic of restrictive cardiomyopathy, including hepatic congestion and abdominal distention 1
- Early and prominent fluid retention with dominant right-sided symptoms is a hallmark presentation that differentiates restrictive from other cardiomyopathy types 1
- Exertional intolerance results from impaired diastolic filling and reduced cardiac output, despite often preserved systolic function in early stages 1
Why Not the Other Options
Dilated Cardiomyopathy (Option A)
- Dilated cardiomyopathy presents with biventricular enlargement and systolic dysfunction as the primary feature 2
- Symptoms typically include left-sided heart failure (pulmonary congestion, orthopnea, paroxysmal nocturnal dyspnea) before right-sided symptoms become dominant 3
- The early prominence of hepatic congestion and right-sided symptoms argues against this diagnosis 1
Hypertrophic Cardiomyopathy (Option C)
- Hypertrophic cardiomyopathy primarily presents with exertional dyspnea and chest pain due to diastolic dysfunction and outflow obstruction 4
- Right-sided symptoms are not characteristically dominant or early in hypertrophic cardiomyopathy 4
- The disease is notable for massive ventricular hypertrophy rather than the restrictive physiology described 5
Ischemic Cardiomyopathy (Option D)
- Ischemic cardiomyopathy results from coronary artery disease and typically presents with regional wall motion abnormalities and systolic dysfunction 2
- The pattern of early, dominant right-sided symptoms with hepatic congestion is atypical for ischemic disease 1
Critical Diagnostic Considerations
In a 55-year-old male with this presentation, cardiac amyloidosis (particularly transthyretin amyloidosis) should be strongly considered as it is a common cause of restrictive cardiomyopathy in men over 50 years 1, 6, 7
Initial Diagnostic Workup
- Echocardiography should demonstrate preserved or near-normal left ventricular systolic function, biatrial enlargement disproportionate to ventricular size, and restrictive mitral inflow pattern 1
- Elevated filling pressures (elevated E/e' ratio) will be present despite preserved ejection fraction 1
- Cardiac MRI can provide additional diagnostic information including late gadolinium enhancement patterns and help differentiate from constrictive pericarditis 1, 8
Common Pitfall
Do not assume all heart failure with edema is dilated cardiomyopathy — restrictive cardiomyopathy can present with severe peripheral edema despite preserved ejection fraction 1. The early prominence of right-sided symptoms and hepatic congestion in the setting of exertional intolerance should immediately raise suspicion for restrictive physiology rather than systolic dysfunction 6, 8.