Cardiology · Pericardial Disease

Constrictive Pericarditis

USMLE2PANCE
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Bets

The facts most likely to be tested

1

The most common clinical presentation is right-sided heart failure symptoms including peripheral edema, ascites, and elevated jugular venous pressure despite preserved left ventricular systolic function.

Confidence:
2

A pericardial knock is a high-pitched, early diastolic sound occurring shortly after S2 that represents the abrupt cessation of ventricular filling.

Confidence:
3

Kussmaul sign, defined as a paradoxical rise or lack of decline in jugular venous pressure during inspiration, is a classic physical exam finding.

Confidence:
4

Friedreich sign manifests as an exaggerated, rapid y-descent in the jugular venous waveform due to the sudden, early diastolic filling of the ventricles.

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5

Echocardiography typically reveals pericardial thickening or calcification and septal bounce (ventricular interdependence) during respiration.

Confidence:
6

Cardiac catheterization demonstrates equalization of diastolic pressures in all four heart chambers, a hallmark hemodynamic feature.

Confidence:
7

The definitive treatment for symptomatic patients is pericardiectomy to relieve the restrictive constraint on the heart.

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A 58-year-old male presents with progressive fatigue, abdominal distension, and lower extremity swelling. He has a history of tuberculous pericarditis treated 10 years ago. Physical examination reveals distended neck veins that increase with inspiration, a pericardial knock on auscultation, and hepatomegaly. An echocardiogram shows pericardial thickening and a septal bounce during inspiration. His cardiac catheterization shows equalization of diastolic pressures across all chambers.

What is the most likely diagnosis?

+Reveal answer

Constrictive pericarditis

The patient exhibits classic signs of right-sided heart failure, Kussmaul sign, and a pericardial knock, which, combined with the history of TB and hemodynamic equalization, confirms constrictive pericarditis.

Mo

Depth

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High yield triage

Etiology / Epidemiology

Commonly follows tuberculosis (developing world) or cardiac surgery/radiation (developed world).

Clinical Manifestations

Presents with right-sided heart failure and Kussmaul sign; pericardial knock is pathognomonic.

Diagnosis

Cardiac catheterization shows dip-and-plateau (square root sign) waveform.

Treatment

Pericardiectomy is the definitive treatment; avoid diuretics if hemodynamically unstable.

Prognosis

Chronic progression leads to severe cachexia and refractory heart failure.

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Epidemiology & Etiology

In the US, idiopathic or viral etiologies are most common, followed by post-surgical scarring. Radiation therapy for malignancy is a major risk factor. In endemic regions, Mycobacterium tuberculosis remains the leading cause.

Pertinent Anatomy

The pericardium becomes rigid and fibrotic, encasing the heart. This prevents normal diastolic expansion, leading to impaired ventricular filling.

Pathophysiology

Rigid pericardium causes ventricular interdependence, where filling of one ventricle restricts the other. This leads to equalization of diastolic pressures across all four chambers. Venous return is impaired, causing systemic congestion and Kussmaul sign.

Clinical Manifestations

Patients present with peripheral edema, ascites, and hepatomegaly. The pericardial knock is an early diastolic sound caused by sudden cessation of ventricular filling. Red flags include pulsus paradoxus (less common than in tamponade) and severe jugular venous distension.

Diagnosis

Echocardiography shows thickened pericardium and septal bounce. Cardiac catheterization is the gold standard, demonstrating the dip-and-plateau sign. CT/MRI is used to quantify pericardial thickness >4mm.

Treatment

Initial management involves diuretics for symptom control, but avoid aggressive diuresis as preload is required to maintain cardiac output. Pericardiectomy is the definitive treatment for symptomatic patients. Contraindications include patients with severe comorbidities where surgical risk outweighs benefit.

Prognosis

Without surgery, the condition is progressive and irreversible. Pericardiectomy carries a high mortality risk, often exceeding 10-15% in complex cases.

Differential Diagnosis

Restrictive Cardiomyopathy: No pericardial calcification; elevated BNP

Cardiac Tamponade: Pulsus paradoxus >10mmHg; no dip-and-plateau

Right Ventricular Infarction: ST elevations in V4R; hypotension

Cirrhosis: No elevated JVP; stigmata of chronic liver disease

Tricuspid Regurgitation: Holosystolic murmur; no pericardial knock