Constrictive Pericarditis

1. Overview

Constrictive pericarditis (CP) is a clinical syndrome resulting from fibrotic thickening and/or calcification of the pericardium that impairs diastolic ventricular filling. [1] The rigid, non-compliant pericardial shell encases the heart, preventing adequate expansion during diastole and leading to systemic venous congestion with predominantly right-sided heart failure manifestations. [2]

This condition represents the end-stage of a spectrum of pericardial inflammatory diseases, with progression from acute pericarditis through effusive-constrictive pericarditis to established constriction occurring over months to years. [3] The hallmark pathophysiological feature is enhanced ventricular interdependence within a fixed pericardial space, creating the characteristic respiratory variation in ventricular filling that distinguishes constriction from other causes of heart failure. [4]

Clinical Significance

Constrictive pericarditis is critically important because:

• It mimics right heart failure but is surgically curable with pericardiectomy
• Delayed diagnosis leads to progressive hepatic dysfunction and cardiac cachexia
• Differentiation from restrictive cardiomyopathy (RCM) is essential as treatments differ fundamentally
• Mortality without surgical intervention approaches 90% at 5 years in symptomatic patients [5]

Key Clinical Message

"Right heart failure with preserved systolic function and raised JVP that rises paradoxically with inspiration (Kussmaul's sign) should prompt immediate consideration of constrictive pericarditis."

---

2. Epidemiology

Incidence and Prevalence

The true incidence of constrictive pericarditis is difficult to establish due to heterogeneous etiologies and variable geographic distribution. In developed countries, CP develops in approximately 0.2-0.4% of patients following acute pericarditis. [6] The incidence following recurrent pericarditis is higher, reaching 2-3% in patients with multiple recurrences. [3]

Demographics

• Age: Median age at presentation is 45-60 years [2]
• Sex: Male predominance (2-3:1 ratio) [1]
• Ethnicity: Reflects underlying etiology distribution (TB-endemic regions vs developed countries)

Risk Factors

Clinical Pearl: Geographic Considerations: In sub-Saharan Africa and Southeast Asia, tuberculosis accounts for up to 90% of CP cases. In developed countries, idiopathic/viral causes predominate, followed by post-cardiac surgery and radiation-induced constriction. [8]

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3. Etiology

Primary Causes

The etiology of constrictive pericarditis varies significantly by geographic region and has evolved over time with changes in disease patterns and medical interventions.

Tuberculous Pericarditis

Tuberculous pericarditis deserves special attention as the leading cause of CP globally. [8]

Pathogenesis:

• Direct spread from mediastinal lymph nodes
• Hematogenous dissemination from pulmonary TB
• Extension from pleural or bone TB

Disease Progression:

1. Exudative stage: Protein-rich effusion with polymorphonuclear cells
2. Absorptive stage: Fibrin deposition, granulomatous inflammation
3. Constrictive stage: Fibrosis, calcification (develops in 30-60% if untreated) [8]

Risk of Constriction:

• Without treatment: 30-60% develop constriction
• With anti-tuberculous therapy alone: 17-40%
• With anti-TB therapy + corticosteroids: Controversial (possible reduction) [9]

Radiation-Induced Constrictive Pericarditis

Radiation-induced CP represents a particularly challenging subset with important clinical implications. [10]

Risk Factors for Development:

• Total dose > 30 Gy to cardiac silhouette
• Anterior/mantle field radiation
• Absence of subcarinal shielding
• Concurrent chemotherapy (especially anthracyclines)
• Young age at time of radiation

Latency Period: Mean 10-15 years (range 2-40 years)

Associated Findings (often coexist):

• Coronary artery disease (proximal, ostial lesions)
• Valvular disease (aortic, mitral regurgitation)
• Myocardial fibrosis (restrictive physiology may coexist)
• Conduction abnormalities

Exam Detail: Why Radiation-Induced CP Has Worst Surgical Outcomes:

1. Concurrent myocardial fibrosis creates mixed constrictive-restrictive physiology
2. Densely adherent pericardium increases surgical complexity
3. Associated coronary disease requires concomitant revascularization
4. Mediastinal fibrosis complicates surgical access
5. Prior radiation impairs wound healing Perioperative mortality reaches 15-21% compared to 6-12% for other etiologies. [10]

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4. Pathophysiology

Molecular and Cellular Mechanisms

The transformation from normal pericardium to constrictive fibrosis involves complex inflammatory and fibrotic cascades. [1,2]

Phase 1: Initial Injury and Inflammation

Initial Insult (TB, Viral, Radiation, Surgery, Trauma)
                    ↓
┌─────────────────────────────────────────────────────────────────┐
│              ACUTE INFLAMMATORY RESPONSE                        │
├─────────────────────────────────────────────────────────────────┤
│  • Mesothelial cell activation                                  │
│  • Neutrophil and macrophage infiltration                       │
│  • Release of pro-inflammatory cytokines:                       │
│    - IL-1β, IL-6, TNF-α                                        │
│    - Interferon-γ (especially TB)                              │
│  • Fibrin deposition on pericardial surfaces                   │
│  • Increased vascular permeability → effusion                  │
└─────────────────────────────────────────────────────────────────┘

Phase 2: Fibroproliferative Response

                    ↓
┌─────────────────────────────────────────────────────────────────┐
│            FIBROPROLIFERATIVE PHASE                             │
├─────────────────────────────────────────────────────────────────┤
│  • Activation of fibroblasts and myofibroblasts                │
│  • TGF-β signaling cascade activation                          │
│  • Extracellular matrix deposition:                            │
│    - Collagen types I and III                                  │
│    - Fibronectin                                               │
│    - Proteoglycans                                             │
│  • Granulation tissue formation                                │
│  • Neovascularization                                          │
└─────────────────────────────────────────────────────────────────┘

Phase 3: Fibrosis and Calcification

                    ↓
┌─────────────────────────────────────────────────────────────────┐
│         CHRONIC FIBROSIS AND CALCIFICATION                      │
├─────────────────────────────────────────────────────────────────┤
│  • Dense collagen deposition (pericardial thickening > 4mm)     │
│  • Pericardial fusion (visceral + parietal layers)             │
│  • Progressive calcification (dystrophic):                     │
│    - Calcium phosphate deposition                              │
│    - Common in TB (50-70% calcify)                            │
│  • Loss of pericardial elasticity                              │
│  • Complete encasement of heart ("pericardial armor")          │
└─────────────────────────────────────────────────────────────────┘

Hemodynamic Consequences

The rigid, non-compliant pericardium fundamentally alters cardiac filling dynamics, creating the characteristic hemodynamic profile of constriction. [4,11]

Fundamental Hemodynamic Principles

┌─────────────────────────────────────────────────────────────────────────────┐
│           CONSTRICTIVE PERICARDITIS - HEMODYNAMIC CONSEQUENCES              │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                             │
│   1. FIXED CARDIAC VOLUME                                                   │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │  Total intrapericardial volume is FIXED                             │   │
│   │  Heart chambers compete for limited space                           │   │
│   │  ↑ Volume in one ventricle → ↓ Volume in other ventricle           │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                              ↓                                              │
│   2. IMPAIRED DIASTOLIC FILLING                                             │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │  Early diastole: Rapid filling (pericardium not yet limiting)       │   │
│   │  Mid-late diastole: Abrupt cessation when pericardial limit reached│   │
│   │  Creates "dip-and-plateau" or "square root" sign                    │   │
│   │                                                                     │   │
│   │  Pressure (mmHg)                                                    │   │
│   │       │                                                             │   │
│   │    20 │          ─────────────── ← Plateau (pericardial limit)     │   │
│   │       │         /                                                   │   │
│   │    10 │        /                                                    │   │
│   │       │       / ← Rapid early filling (dip)                        │   │
│   │     0 │──────/                                                      │   │
│   │       └──────────────────────────────────────────────               │   │
│   │              Early     Mid      Late    Diastole                    │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                              ↓                                              │
│   3. ENHANCED VENTRICULAR INTERDEPENDENCE                                   │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │                                                                     │   │
│   │   INSPIRATION                        EXPIRATION                     │   │
│   │   ↓ Intrathoracic pressure           ↑ Intrathoracic pressure       │   │
│   │   ↓ Pulmonary venous pressure        ↑ Pulmonary venous pressure    │   │
│   │   ↓ LV filling gradient              ↑ LV filling gradient          │   │
│   │   ↓ LV filling                       ↑ LV filling                   │   │
│   │   Septum shifts LEFT                 Septum shifts RIGHT            │   │
│   │   ↑ RV filling (takes LV space)      ↓ RV filling                   │   │
│   │                                                                     │   │
│   │   Key: Changes in one ventricle are RECIPROCAL to the other         │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                              ↓                                              │
│   4. EQUALIZATION OF DIASTOLIC PRESSURES                                    │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │  All chambers equilibrate to pericardial pressure                   │   │
│   │                                                                     │   │
│   │  LVEDP ≈ RVEDP ≈ RA mean ≈ LA mean ≈ PCWP ≈ PA diastolic           │   │
│   │                                                                     │   │
│   │  All pressures within 5 mmHg of each other                         │   │
│   │  (Classic criterion: LVEDP - RVEDP ≤ 5 mmHg)                       │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                              ↓                                              │
│   5. SYSTEMIC VENOUS CONGESTION                                             │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │  • Elevated CVP/JVP (typically 15-25 mmHg)                         │   │
│   │  • Hepatomegaly with pulsatile liver                               │   │
│   │  • Ascites (often prominent, disproportionate)                     │   │
│   │  • Peripheral edema (may be less prominent than ascites)           │   │
│   │  • Protein-losing enteropathy (late complication)                  │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

Why Kussmaul's Sign Occurs

In normal physiology, inspiration decreases intrathoracic pressure, increasing venous return to the right heart and causing JVP to fall. In constrictive pericarditis:

1. The rigid pericardium cannot accommodate increased RV filling
2. Increased venous return cannot be accepted by the constricted RV
3. Blood "backs up" into the systemic veins
4. JVP rises paradoxically with inspiration

Exam Detail: Kussmaul's Sign Differential Diagnosis:

• Constrictive pericarditis (most specific)
• Right ventricular infarction
• Restrictive cardiomyopathy
• Severe tricuspid regurgitation
• Massive pulmonary embolism
• Superior vena cava syndrome

Key Point: Kussmaul's sign is NOT typical of cardiac tamponade (where pulsus paradoxus predominates)

Comparison with Cardiac Tamponade

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5. Clinical Presentation

Symptom Profile

The clinical presentation of constrictive pericarditis is insidious, often developing over months to years. [1,2] Symptoms are predominantly those of right-sided heart failure with systemic venous congestion.

Cardinal Symptoms

Associated Symptoms

• Orthopnea: Less prominent than in left heart failure
• Paroxysmal nocturnal dyspnea: Uncommon
• Chest pain: Usually absent (except if associated with active pericarditis)
• Palpitations: If atrial fibrillation develops (25-50% of cases)
• Weight gain: Fluid retention

Clinical Pearl: Diagnostic Clue: The pattern of "right heart failure symptoms (ascites, edema) out of proportion to left heart failure symptoms (dyspnea, orthopnea)" should raise suspicion for constrictive pericarditis or restrictive cardiomyopathy.

History Taking: Key Points to Elicit

1. Temporal course: When did symptoms begin? Gradual or sudden onset?
2. Prior pericarditis: Any previous episodes of chest pain, fever?
3. Cardiac surgery history: CABG, valve replacement, transplant?
4. Radiation therapy: Mediastinal irradiation for any malignancy?
5. Tuberculosis exposure: Travel to endemic areas, prior TB, contact history?
6. Connective tissue disease: RA, SLE, scleroderma symptoms?
7. Renal disease: Chronic kidney disease, dialysis?
8. Medication history: Drug-induced pericarditis (hydralazine, procainamide)?

Physical Examination Findings

General Inspection

Cardiovascular Examination

JVP Waveform Analysis

Normal JVP Waveform vs. Constrictive Pericarditis

NORMAL:                          CONSTRICTIVE PERICARDITIS:
      a                                     a
     /\                                    /\
    /  \   c                              /  \    c
   /    \ /\                             /    \  /\
  /      X  \                           /      \/  \
 /      / \  \   v                     /       /    \    v
/      /   \  \ / \                   /       /      \  / \
      x     \  X   y                         x'       \/   y
             \/                                        
                                      
Key: x descent = systolic           "M" or "W" pattern
     y descent = diastolic          Both x and y descents are
                                    PROMINENT and RAPID

The "M" or "W" Pattern

The JVP in constrictive pericarditis shows:

• Prominent x descent: Normal atrial relaxation
• Prominent y descent: Rapid early diastolic filling
• The combination creates an "M" (or inverted "W") appearance

Hepatic Examination

Auscultation

Pericardial Knock:

• High-pitched, early diastolic sound
• Occurs 0.06-0.12 seconds after A2
• Corresponds to abrupt cessation of ventricular filling
• Best heard at left lower sternal border and apex
• Higher pitched than S3
• May be confused with opening snap of mitral stenosis

The Classic Clinical Triad

1. Elevated JVP with Kussmaul's sign (paradoxical rise with inspiration)
2. Pericardial knock on auscultation
3. Hepatomegaly with ascites (often disproportionate to peripheral edema)

Clinical Pearl: Examination Tip for PACES/Clinical Exams: When examining a patient with signs of right heart failure and preserved left ventricular function, always:

1. Assess JVP during respiration (look for Kussmaul's sign)
2. Listen carefully for pericardial knock (early diastole)
3. Palpate the liver for pulsatility
4. Note if ascites is disproportionate to peripheral edema

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6. Differential Diagnosis

The Critical Distinction: Constriction vs. Restriction

Differentiating constrictive pericarditis from restrictive cardiomyopathy (RCM) is one of the most challenging diagnostic problems in cardiology. [12] This distinction is clinically vital as CP is surgically treatable while RCM has limited therapeutic options.

Clinical Differentiation

Echocardiographic Differentiation

Exam Detail: Key Echo Differentiators:

1. Septal Bounce: In constriction, the septum shifts with respiration (left with inspiration, right with expiration). This "septal bounce" or "shudder" is visible on M-mode and 2D echo.

2. Annulus Paradoxus: Normally, lateral mitral annulus e' velocity > medial e' velocity. In constriction, this is reversed (medial > lateral) because the lateral annulus is tethered by the constrictive pericardium.

3. Tissue Doppler e' Velocity: In constriction, e' is preserved (> 8 cm/s) or even increased. In restriction, e' is reduced (less than 8 cm/s) because the myocardium itself is abnormal.

4. Respiratory Variation: Marked respiratory variation in mitral inflow (> 25%) is characteristic of constriction but not restriction.

Cardiac Catheterization Differentiation

The Discordance Sign:

INSPIRATION:                    EXPIRATION:
Constriction:                   Constriction:
RV systolic ↑                   RV systolic ↓
LV systolic ↓  (DISCORDANT)     LV systolic ↑  (DISCORDANT)

Restriction:                    Restriction:
RV systolic ↓                   RV systolic ↑
LV systolic ↓  (CONCORDANT)     LV systolic ↑  (CONCORDANT)

MRI Differentiation

Other Differential Diagnoses

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7. Investigations

Diagnostic Algorithm

┌─────────────────────────────────────────────────────────────────────────────┐
│                    DIAGNOSTIC APPROACH TO SUSPECTED CP                       │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                             │
│   CLINICAL SUSPICION                                                        │
│   • Right heart failure with preserved LVEF                                 │
│   • Elevated JVP + Kussmaul's sign                                         │
│   • History: Prior pericarditis, TB, surgery, radiation                    │
│                          ↓                                                  │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │                    FIRST-LINE INVESTIGATIONS                        │   │
│   │  • ECG: Low voltage, AF, non-specific ST-T changes                  │   │
│   │  • CXR: Calcification, normal/small heart, clear lungs             │   │
│   │  • Echo: Septal bounce, respiratory variation, dilated IVC         │   │
│   │  • Blood tests: BNP (normal/mildly elevated), LFTs, albumin        │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                          ↓                                                  │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │                    SECOND-LINE IMAGING                              │   │
│   │  • Cardiac CT: Pericardial calcification, thickness > 4mm           │   │
│   │  • Cardiac MRI: Pericardial thickness, enhancement, septal motion  │   │
│   │  • CT/MRI also assess for concurrent coronary/valvular disease     │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                          ↓                                                  │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │              CARDIAC CATHETERIZATION (if diagnosis unclear)         │   │
│   │  • Diastolic pressure equalization                                  │   │
│   │  • Square root sign                                                 │   │
│   │  • Discordant ventricular pressure changes with respiration        │   │
│   │  • Coronary angiography if surgery planned                         │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                          ↓                                                  │
│              ┌──────────────────────────────────────┐                       │
│              │   DIAGNOSIS CONFIRMED?               │                       │
│              └──────────────────────────────────────┘                       │
│                    ↓ YES              ↓ NO                                  │
│   ┌──────────────────────────┐  ┌──────────────────────────────────────┐   │
│   │  PROCEED TO MANAGEMENT   │  │  Consider:                           │   │
│   │  • Identify etiology     │  │  • Restrictive cardiomyopathy       │   │
│   │  • Assess surgical risk  │  │  • Endomyocardial biopsy            │   │
│   │  • Plan pericardiectomy  │  │  • Further cardiac imaging          │   │
│   └──────────────────────────┘  └──────────────────────────────────────┘   │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

First-Line Investigations

Electrocardiogram

Chest X-Ray

Clinical Pearl: Important: Normal pericardial thickness on imaging does NOT exclude constrictive pericarditis. Up to 18% of surgically proven CP cases have normal pericardial thickness (less than 2 mm). The diagnosis relies on demonstrating constrictive physiology, not just anatomical thickening. [13]

Laboratory Investigations

BNP in Constrictive Pericarditis

Why BNP is typically normal or only mildly elevated in CP:

• BNP is released in response to myocardial stretch
• In CP, the myocardium itself is normal
• The rigid pericardium limits ventricular wall stress
• BNP > 400 pg/mL more suggestive of RCM than CP

Echocardiography

Echocardiography is the first-line imaging modality for suspected CP. [4,14]

M-Mode Findings

2D Echo Findings

Doppler Findings

Cardiac CT

Cardiac CT provides excellent visualization of pericardial anatomy. [14]

Cardiac MRI

Cardiac MRI is the most comprehensive non-invasive imaging modality. [14,15]

Exam Detail: MRI Protocol for CP:

1. Black-blood sequences: Assess pericardial thickness and morphology
2. Cine SSFP sequences: Evaluate ventricular function and septal motion
3. Real-time cine during respiration: Demonstrate ventricular interdependence
4. Late gadolinium enhancement: Identify pericardial inflammation (reversibility potential) and exclude myocardial disease
5. T1 mapping: Characterize pericardial tissue

Cardiac Catheterization

Right and left heart catheterization remains the gold standard for hemodynamic assessment. [11]

Classic Hemodynamic Findings

Pressure Tracings

SIMULTANEOUS LV AND RV PRESSURE RECORDING:

Pressure (mmHg)
      │
  120 │         LV systolic                RV systolic
      │         /\                         /\
  100 │        /  \                       /  \
      │       /    \                     /    \
   80 │      /      \                   /      \
      │     /        \                 /        \
   60 │    /          \               /          \
      │   /            \             /            \
   40 │  /              \           /              \
      │ /                ─────────────────────────── ← Plateau (equalized diastolic)
   20 │/                  Dip ↓              Dip ↓
      │                    "Square root" sign
    0 │──────────────────────────────────────────────────────
      │
         Systole    Diastole    Systole    Diastole

Etiology-Specific Investigations

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8. Classification and Staging

Classification by Etiology

Classification by Pathophysiology

Staging by Clinical Severity

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9. Management

Management Algorithm

┌─────────────────────────────────────────────────────────────────────────────┐
│            CONSTRICTIVE PERICARDITIS MANAGEMENT ALGORITHM                   │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                             │
│   CONFIRMED DIAGNOSIS OF CONSTRICTIVE PERICARDITIS                          │
│                          ↓                                                  │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │                 ASSESS FOR TRANSIENT CONSTRICTION                   │   │
│   │  • Early after acute pericarditis (less than 3 months)                       │   │
│   │  • Pericardial inflammation on MRI (LGE positive)                  │   │
│   │  • Recent onset symptoms                                            │   │
│   │  • No calcification on imaging                                      │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                          ↓                                                  │
│              ┌──────────────────────────────────────┐                       │
│              │   TRANSIENT CONSTRICTION LIKELY?      │                      │
│              └──────────────────────────────────────┘                       │
│                    ↓ YES              ↓ NO                                  │
│   ┌──────────────────────────┐  ┌──────────────────────────────────────┐   │
│   │  TRIAL OF MEDICAL Rx     │  │      ESTABLISHED CONSTRICTION        │   │
│   │  • NSAIDs + Colchicine   │  │                                      │   │
│   │  • ± Corticosteroids     │  │  Proceed to surgical assessment     │   │
│   │  • 2-3 month trial       │  │                                      │   │
│   │  • Repeat imaging        │  │                                      │   │
│   └──────────────────────────┘  └──────────────────────────────────────┘   │
│           ↓ No improvement               ↓                                  │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │                    SURGICAL ASSESSMENT                              │   │
│   │  • Cardiothoracic surgery referral                                  │   │
│   │  • Coronary angiography (if radiation-induced or age > 40)          │   │
│   │  • Pulmonary function tests                                         │   │
│   │  • Nutritional assessment (albumin, pre-albumin)                    │   │
│   │  • Hepatic function assessment (coagulation, bilirubin)            │   │
│   │  • Risk score calculation (EuroSCORE, STS)                          │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                          ↓                                                  │
│              ┌──────────────────────────────────────┐                       │
│              │   ACCEPTABLE SURGICAL RISK?           │                      │
│              └──────────────────────────────────────┘                       │
│                    ↓ YES              ↓ NO                                  │
│   ┌──────────────────────────┐  ┌──────────────────────────────────────┐   │
│   │     PERICARDIECTOMY      │  │       PALLIATIVE MANAGEMENT          │   │
│   │  • Median sternotomy     │  │  • Diuretics (cautious)              │   │
│   │  • Radical excision      │  │  • Sodium restriction                 │   │
│   │  • ± CPB if needed       │  │  • Paracentesis for ascites          │   │
│   │                          │  │  • Palliative care involvement       │   │
│   └──────────────────────────┘  └──────────────────────────────────────┘   │
│                          ↓                                                  │
│   ┌─────────────────────────────────────────────────────────────────────┐   │
│   │                      POST-OPERATIVE CARE                            │   │
│   │  • ICU monitoring (low cardiac output syndrome common)             │   │
│   │  • Inotropic support if needed                                      │   │
│   │  • Gradual volume expansion                                         │   │
│   │  • Follow-up echo at 1, 3, 6 months                                │   │
│   │  • Full hemodynamic recovery may take 3-6 months                   │   │
│   └─────────────────────────────────────────────────────────────────────┘   │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

Medical Management

Medical therapy in constrictive pericarditis is primarily symptomatic and serves as a bridge to surgery or for patients who are not surgical candidates. [1,2]

Diuretic Therapy

Cautions with Diuretics:

• Patients with CP are preload-dependent
• Excessive diuresis can precipitate low cardiac output
• "Dry" patients may have worse symptoms
• Aim for symptomatic relief without hypotension

Anti-inflammatory Therapy (Transient Constriction)

Clinical Pearl: Identifying Transient Constriction: Transient constrictive pericarditis should be suspected when:

1. Symptoms developed within 3 months of acute pericarditis
2. Pericardial late gadolinium enhancement present on MRI (inflammation)
3. No pericardial calcification
4. CRP/ESR elevated (ongoing inflammation)

A 2-3 month trial of anti-inflammatory therapy is reasonable before committing to surgery. [16]

Etiology-Specific Treatment

Surgical Management: Pericardiectomy

Pericardiectomy is the definitive treatment for established constrictive pericarditis. [5,17]

Indications for Surgery

Absolute Indications:

• Symptomatic chronic constrictive pericarditis (NYHA II-IV)
• Established fibrosis/calcification on imaging
• Failed medical management

Relative Indications:

• Transient constriction unresponsive to 2-3 months of anti-inflammatory therapy
• Effusive-constrictive pericarditis with persistent constriction after drainage

Contraindications:

• End-stage disease with severe cachexia
• Multi-organ failure
• Prohibitive surgical risk
• Concurrent severe myocardial disease (radiation-induced)

Surgical Technique

Surgical Steps:

1. Median sternotomy with CPB standby
2. Identify phrenic nerves bilaterally
3. Incise pericardium over LV
4. Develop plane between pericardium and epicardium
5. Extend dissection laterally to phrenic nerves
6. Extend anteriorly to RV and RA
7. Extend inferiorly to diaphragm
8. Extend superiorly to great vessels
9. Remove as much pericardium as safely possible
10. Hemostasis and chest closure

Exam Detail: Why Complete Pericardiectomy is Important: Incomplete pericardiectomy is associated with worse outcomes. The goal is to remove pericardium from phrenic nerve to phrenic nerve, including the anterior, lateral, and inferior surfaces of both ventricles. The pericardium over the atria may be left if difficult to remove safely. Leaving residual constricting pericardium results in persistent symptoms and may require reoperation.

Surgical Outcomes

Predictors of Poor Surgical Outcome: [17]

1. Radiation-induced etiology
2. Advanced NYHA class (III-IV)
3. Older age
4. Hepatic dysfunction (elevated bilirubin, prolonged PT)
5. Renal impairment
6. Atrial fibrillation
7. Low serum albumin
8. Left ventricular dysfunction

Post-Operative Management

Immediate Post-Operative Period:

• ICU monitoring for 24-48 hours
• Watch for low cardiac output syndrome (occurs in 25-30%)
• Inotropic support may be needed (dobutamine, milrinone)
• Avoid excessive volume; allow gradual preload optimization
• Watch for bleeding (especially with calcified pericardium)

Delayed Recovery:

• Hemodynamic improvement may be gradual (weeks to months)
• "Myocardial stunning" may occur transiently
• Echo at 1, 3, 6 months to assess improvement
• Full functional recovery may take 6-12 months

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10. Complications

Disease Complications

Surgical Complications

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11. Prognosis

Natural History

Untreated constrictive pericarditis has a poor prognosis:

• Progressive deterioration over months to years
• 5-year survival without surgery: approximately 10-20% [5]
• Death from cardiac cachexia, hepatic failure, or arrhythmia

Post-Surgical Prognosis

Long-Term Survival Data

Based on large surgical series: [17,18]

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12. Special Populations

Tuberculous Pericarditis

TB pericarditis requires special consideration as the leading global cause of CP. [8,9]

Management Principles:

1. Diagnosis: High clinical suspicion in endemic areas; pericardial fluid analysis (ADA > 40 U/L suggestive); pericardial biopsy if available
2. Anti-tuberculous therapy: Standard 4-drug regimen (RIPE) for 6-9 months
3. Corticosteroids: Controversial; may reduce progression to constriction but meta-analyses show variable benefit [9]
4. Timing of surgery: If constriction develops despite treatment, surgery is indicated

Prognosis:

• With treatment: 17-40% still develop constriction
• Surgical outcomes: Intermediate between idiopathic and radiation-induced

Radiation-Induced Constrictive Pericarditis

The most challenging subset with worst outcomes. [10]

Key Considerations:

1. Associated cardiac disease: Screen for CAD (often proximal/ostial), valvular disease, myocardial fibrosis
2. Coronary angiography: Mandatory pre-operatively
3. Mixed physiology: May have both constrictive and restrictive elements (myocardial fibrosis)
4. Surgical complexity: Densely adherent pericardium, poor tissue quality
5. Consent: Discuss higher mortality (15-21%) and potential for incomplete relief

Post-Cardiac Surgery Constrictive Pericarditis

Occurs in 0.2-0.3% of cardiac surgery patients with median presentation 2-3 years post-operatively. [7]

Characteristics:

• May present early (less than 6 months) or late (years)
• Early cases may be transient (respond to anti-inflammatory therapy)
• Late cases usually require surgery
• Surgical outcomes generally good (experienced centers have lower mortality)

Transient Constrictive Pericarditis

A subset that resolves with anti-inflammatory therapy. [16]

Features Suggesting Transient Constriction:

1. Recent acute pericarditis (less than 3 months)
2. Pericardial inflammation on MRI (late gadolinium enhancement)
3. Elevated inflammatory markers (CRP, ESR)
4. No pericardial calcification
5. Symptoms not severe (NYHA I-II)

Management:

• Trial of colchicine + NSAIDs/aspirin for 2-3 months
• Repeat imaging to assess resolution
• If no improvement, proceed to surgery

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13. Exam-Focused Content

Common Exam Questions

1. "What is Kussmaul's sign and what does it indicate?"
2. "How do you differentiate constrictive pericarditis from restrictive cardiomyopathy?"
3. "What are the causes of constrictive pericarditis?"
4. "Describe the hemodynamic findings in constrictive pericarditis."
5. "What is the definitive treatment for constrictive pericarditis?"
6. "Which etiology has the worst surgical outcomes and why?"

Viva Points

Viva Point: Opening Statement: "Constrictive pericarditis is a clinical syndrome caused by fibrotic thickening and/or calcification of the pericardium that impairs diastolic ventricular filling, leading to systemic venous congestion with predominantly right-sided heart failure manifestations."

Key Points to Mention:

1. Etiology: Idiopathic/viral (40-50% developed countries), TB (leading cause globally), post-cardiac surgery, radiation
2. Pathophysiology: Thickened pericardium → fixed cardiac volume → enhanced ventricular interdependence → impaired diastolic filling
3. Classic signs: Elevated JVP, Kussmaul's sign, pericardial knock, hepatomegaly with ascites
4. Diagnosis: Echo (septal bounce, respiratory variation), CT/MRI (pericardial thickening/calcification), catheterization (diastolic equalization, discordant pressures)
5. Key differential: Restrictive cardiomyopathy (different treatment implications)
6. Treatment: Pericardiectomy is definitive; medical therapy is symptomatic only
7. Prognosis: 6-12% perioperative mortality; radiation-induced has worst outcomes (15-21% mortality)

Model Answer: Constriction vs. Restriction

Q: "How would you differentiate constrictive pericarditis from restrictive cardiomyopathy?"

"I would approach this systematically across clinical, imaging, and hemodynamic domains:

Clinically, I would look for:

• History of pericarditis, TB, cardiac surgery, or radiation (suggests constriction)
• Pericardial knock on auscultation (suggests constriction)
• Family history of cardiomyopathy or systemic disease features like amyloidosis (suggests restriction)

On echocardiography, the key differentiators are:

• Septal bounce with respiration (constriction)
• Marked respiratory variation in mitral inflow > 25% (constriction)
• Tissue Doppler e' velocity: preserved > 8 cm/s in constriction, reduced in restriction
• Annulus paradoxus with medial e' > lateral e' (constriction)

On cardiac MRI, I would look for:

• Pericardial thickening > 4 mm (constriction)
• Pericardial late gadolinium enhancement (constriction with inflammation)
• Myocardial late gadolinium enhancement in pattern suggesting infiltration (restriction)

At cardiac catheterization, the key finding is:

• Discordant ventricular pressures with respiration (RV and LV move oppositely) in constriction
• Concordant ventricular pressures in restriction
• RVEDP/LVEDP ratio often approaches 1 in constriction

This distinction is crucial because constrictive pericarditis is surgically treatable with pericardiectomy, while restrictive cardiomyopathy has limited treatment options and poorer prognosis."

Common Mistakes (What Gets You Failed)

• Forgetting to mention Kussmaul's sign when describing clinical features
• Confusing the differences between constriction and restriction
• Not knowing that pericardiectomy is the definitive treatment
• Stating that pulsus paradoxus is a feature of constriction (it's more typical of tamponade)
• Not mentioning TB as the leading global cause
• Forgetting that radiation-induced has the worst surgical prognosis
• Not knowing that normal pericardial thickness doesn't exclude the diagnosis

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14. Key Guidelines

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15. Patient Explanation

What is Constrictive Pericarditis?

"Your heart is surrounded by a thin, protective sac called the pericardium. Normally, this sac is flexible and allows your heart to expand freely with each heartbeat. In constrictive pericarditis, this sac has become thick, stiff, and sometimes calcified - often due to a past infection, inflammation, previous heart surgery, or radiation treatment.

Think of it like your heart being wrapped in a rigid shell that won't stretch. When your heart tries to fill with blood between beats, the stiff pericardium prevents it from expanding properly. This causes blood to back up, particularly to your liver and legs, causing swelling and fluid buildup."

What Are the Symptoms?

"The main symptoms include:

• Swelling in your legs and especially your belly (ascites)
• Shortness of breath with activity
• Fatigue and reduced exercise tolerance
• Loss of appetite and feeling full quickly
• Weight gain from fluid retention

Many people notice their belly swelling more than their legs - this is actually typical of this condition."

How is it Treated?

"The main treatment is surgery to remove the thickened pericardium - called a pericardiectomy. This frees your heart to expand and fill normally again. The surgery is performed through an incision in your chest (sternotomy) and involves carefully peeling away the thickened pericardial tissue.

While waiting for surgery, or if surgery isn't possible, we use water pills (diuretics) to help reduce fluid buildup, and dietary salt restriction. These treatments help with symptoms but don't cure the underlying problem.

Most people feel significantly better after surgery, though it may take several weeks to months for full improvement as your heart adjusts to working normally again."

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16. References

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2. Syed FF, Schaff HV, Oh JK. Constrictive pericarditis—a curable diastolic heart failure. Nat Rev Cardiol. 2014;11(9):530-544. doi:10.1038/nrcardio.2014.100

3. Imazio M, Brucato A, Maestroni S, et al. Risk of constrictive pericarditis after acute pericarditis. Circulation. 2011;124(11):1270-1275. doi:10.1161/CIRCULATIONAHA.111.018580

4. Welch TD, Ling LH, Espinosa RE, et al. Echocardiographic diagnosis of constrictive pericarditis: Mayo Clinic criteria. Circ Cardiovasc Imaging. 2014;7(3):526-534. doi:10.1161/CIRCIMAGING.113.001613

5. Bertog SC, Thambidorai SK, Parber K, et al. Constrictive pericarditis: etiology and cause-specific survival after pericardiectomy. J Am Coll Cardiol. 2004;43(8):1445-1452. doi:10.1016/j.jacc.2003.11.048

6. Imazio M, Gaita F, LeWinter M. Evaluation and treatment of pericarditis: a systematic review. JAMA. 2015;314(14):1498-1506. doi:10.1001/jama.2015.12763

7. Nishimura S, Izumi C, Amano M, et al. Incidence and clinical features of constrictive pericarditis after cardiac surgery. J Am Heart Assoc. 2022;11(4):e023640. doi:10.1161/JAHA.121.023640

8. Mayosi BM, Burgess LJ, Doubell AF. Tuberculous pericarditis. Circulation. 2005;112(23):3608-3616. doi:10.1161/CIRCULATIONAHA.105.543066

9. Wiysonge CS, Ntsekhe M, Thabane L, et al. Interventions for treating tuberculous pericarditis. Cochrane Database Syst Rev. 2017;9(9):CD000526. doi:10.1002/14651858.CD000526.pub2

10. Cutter DJ, Schaapveld M, Darby SC, et al. Risk of valvular heart disease after treatment for Hodgkin lymphoma. J Natl Cancer Inst. 2015;107(4):djv008. doi:10.1093/jnci/djv008

11. Talreja DR, Nishimura RA, Oh JK, Holmes DR. Constrictive pericarditis in the modern era: novel criteria for diagnosis in the cardiac catheterization laboratory. J Am Coll Cardiol. 2008;51(3):315-319. doi:10.1016/j.jacc.2007.09.039

12. Garcia MJ. Constrictive pericarditis versus restrictive cardiomyopathy? J Am Coll Cardiol. 2016;67(17):2061-2076. doi:10.1016/j.jacc.2016.01.076

13. Talreja DR, Edwards WD, Danielson GK, et al. Constrictive pericarditis in 26 patients with histologically normal pericardial thickness. Circulation. 2003;108(15):1852-1857. doi:10.1161/01.CIR.0000087606.18453.FD

14. Klein AL, Abbara S, Agler DA, et al. American Society of Echocardiography clinical recommendations for multimodality cardiovascular imaging of patients with pericardial disease. J Am Soc Echocardiogr. 2013;26(9):965-1012. doi:10.1016/j.echo.2013.06.023

15. Zurick AO, Bolen MA, Kwon DH, et al. Pericardial delayed hyperenhancement with CMR imaging in patients with constrictive pericarditis undergoing surgical pericardiectomy: a case series with histopathological correlation. JACC Cardiovasc Imaging. 2011;4(11):1180-1191. doi:10.1016/j.jcmg.2011.08.011

16. Haley JH, Tajik AJ, Danielson GK, et al. Transient constrictive pericarditis: causes and natural history. J Am Coll Cardiol. 2004;43(2):271-275. doi:10.1016/j.jacc.2003.08.032

17. George TJ, Arnaoutakis GJ, Beaty CA, et al. Contemporary etiologies, risk factors, and outcomes after pericardiectomy. Ann Thorac Surg. 2012;94(2):445-451. doi:10.1016/j.athoracsur.2012.03.079

18. Cho YH, Schaff HV, Dearani JA, et al. Completion pericardiectomy for recurrent constrictive pericarditis: importance of timing of recurrence on outcomes. Ann Thorac Surg. 2012;93(4):1236-1240. doi:10.1016/j.athoracsur.2012.01.010

19. Ling LH, Oh JK, Schaff HV, et al. Constrictive pericarditis in the modern era: evolving clinical spectrum and impact on outcome after pericardiectomy. Circulation. 1999;100(13):1380-1386. doi:10.1161/01.CIR.100.13.1380

20. Feng D, Glockner J, Kim K, et al. Cardiac magnetic resonance imaging pericardial late gadolinium enhancement and elevated inflammatory markers can predict the reversibility of constrictive pericarditis after antiinflammatory medical therapy: a pilot study. Circulation. 2011;124(17):1830-1837. doi:10.1161/CIRCULATIONAHA.111.026070