Right Ventricular Failure 

1. Introduction

The right ventricle is unable to provide adequate forward flow into the pulmonary circulation at normal filling pressures, leading to systemic venous congestion with or without low cardiac output.

In ICU practice, acute RV failure is a hemodynamic emergency — commonly seen in:

• Massive pulmonary embolism
• Acute RV infarction
• Severe pulmonary hypertension
• ARDS with high PEEP
• Post–cardiac surgery
• Sepsis-induced myocardial dysfunction

Understanding RV physiology is essential because the RV behaves very differently from the LV.

2. Right Ventricular Physiology

Structural Features

The RV is:

• Thin-walled
• Highly compliant
• Designed for volume handling, not pressure

RV Pressure-Volume Loop

• Normal RV systolic pressure: 15–30 mmHg
• RV cannot tolerate acute rise in afterload
• Sudden increase in PVR → RV dilates → septal shift → LV collapse

3. Pathophysiology of RV Failure

RV failure develops when:

RV afterload ↑ OR contractility ↓ OR preload overload exceeds compensation

A. Afterload Increase (Most Dangerous)

Causes:

• Pulmonary embolism
• Pulmonary hypertension
• ARDS
• Hypercapnia
• Hypoxia
• High PEEP

Mechanism:

1. Acute rise in PVR
2. RV dilation
3. Increased RV wall tension
4. Septal shift to left (D-shaped LV)
5. ↓ LV filling
6. ↓ Cardiac output
7. Hypotension → coronary hypoperfusion → RV ischemia

This becomes a vicious cycle.

B. RV Contractility Reduction

• Right ventricular myocardial infarction
• Sepsis-induced cardiomyopathy
• Myocarditis
• Post-cardiac surgery

C. Preload Excess

Seen in:

• Tricuspid regurgitation
• Aggressive fluid resuscitation
• Chronic pulmonary hypertension

RV initially compensates via dilation → then fails.

 ICU Causes 

1. Massive PE

• Sudden hypotension
• RV dilation
• McConnell sign

2. ARDS

• Hypoxia
• High PEEP
• Hypercapnia
• Elevated PVR

3. RV Infarction

Associated with inferior MI.

4. Types of RV Failure

1. Acute RV Failure

Sudden rise in afterload.

Examples:

• Massive PE
• Acute RV infarction
• Acute severe ARDS

ICU emergency.

2. Chronic RV Failure (Cor Pulmonale)

Most commonly due to:

• Chronic obstructive pulmonary disease
• Interstitial lung disease
• Chronic pulmonary hypertension

3. Acute on Chronic RV Failure

Example:

• COPD patient with chronic pulmonary hypertension develops acute PE.

These patients:

• Decompensate rapidly
• Require ICU care
• Have poor prognosis

5. Clinical Features

Symptoms

• Dyspnea
• Fatigue
• Abdominal fullness
• Peripheral edema

Signs 

• Elevated JVP
• Prominent v waves (TR)
• Hepatomegaly
• Ascites
• Peripheral edema
• Hypotension (late)

In acute RV failure:

• Shock with clear lungs

Differentiating RVF from LV Failure

6. Hemodynamics 

Pulmonary artery catheter:

• Elevated RAP
• Normal wedge pressure (if isolated RVF)

4️⃣ Echocardiographic Diagnostic Criteria (Most Important Tool in ICU)

Echo is the primary bedside diagnostic modality.

Structural Criteria

• RV dilatation (RV/LV end-diastolic area ratio > 1.0)
• RV basal diameter > 41 mm (apical 4-chamber view)
• D-shaped LV (septal flattening)

Functional Criteria

Acute RV Failure Specific Signs

• McConnell sign (acute PE)
• Severe TR
• Dilated IVC with poor collapse

Seen in:

• Pulmonary embolism

 Diagnostic Criteria in Pulmonary Hypertension–Associated RVF

In chronic RV failure due to:

• Pulmonary hypertension

Criteria include:

• Mean pulmonary artery pressure ≥ 20 mmHg (right heart cath)
• Elevated PVR (>2 Wood units)
• RV enlargement + dysfunction on echo
• Elevated RAP

9. Management of Right Ventricular Failure

Core Principle:

RV is preload dependent but afterload sensitive

Management = Balance preload + reduce afterload + improve contractility

Step 1: Optimize Preload

• Avoid fluid overload
• Small fluid bolus (250 ml) if hypovolemic
• Stop aggressive fluids

Over-resuscitation worsens septal shift.

Step 2: Reduce Afterload

A. Oxygenation

• Avoid hypoxia
• Avoid hypercapnia

B. Reduce PEEP

• Use lowest PEEP compatible with oxygenation

C. Pulmonary Vasodilators

• Inhaled nitric oxide
• Inhaled epoprostenol

Step 3: Improve Contractility

Preferred Inotropes

Avoid pure alpha agents (increase PVR).

Step 4: Maintain Coronary Perfusion

RV perfusion occurs in systole + diastole.

Maintain MAP > 65 mmHg.

Step 5: Specific Treatment

• PE → Thrombolysis
• RV MI → Revascularization
• ARDS → Lung protective ventilation

10. Mechanical Support

In refractory RV failure:

• VA-ECMO
• RV assist device

Used in:

• Massive PE
• Post-cardiotomy RV failure