What are the typical presenting symptoms of pulmonary embolism?

Symptoms of Pulmonary Embolism

Dyspnea is the most common presenting symptom of pulmonary embolism, occurring in 72-82% of patients, followed by chest pain (pleuritic or substernal) in 38-56% of cases. 1, 2

Cardinal Symptoms (The "Big Four")

At least one of these four symptoms occurs in 94% of all PE cases: 3

• Dyspnea (shortness of breath): Present in 72-82% of patients 1, 2

  • In central PE: Acute, severe, and of rapid onset 1, 2
  • In small peripheral PE: Often mild and may be transient 1, 4
  • In patients with pre-existing heart failure or lung disease, worsening dyspnea may be the only symptom 1, 2

• Chest pain: Present in 38-56% of cases 2

  • Pleuritic pain (sharp, stabbing, worse with breathing): Occurs in approximately 52% of patients, caused by pleural irritation from distal emboli 1, 4
  • Substernal angina-like pain: Occurs in 12% of patients, reflects right ventricular ischemia from acute RV strain 1, 4

• Syncope or presyncope: Present in 14-26% of cases 1, 2

  • Associated with higher prevalence of hemodynamic instability and RV dysfunction 5, 1
  • May occur even without overt hemodynamic collapse 1

• Hemoptysis: Present in 5-11% of cases 1, 2

  • Results from alveolar hemorrhage caused by small distal emboli 1

Physical Examination Findings

• Tachypnea (respiratory rate >20/min): Present in approximately 70% of patients 1, 2
• Tachycardia (heart rate >100/min): Present in 26-40% of cases 1, 2
• Signs of deep vein thrombosis (leg swelling): Present in only 10-15% of cases 2
• Fever (>38.5°C): Present in 7% of cases 1
• Cyanosis: Present in 11% of cases 1
• Hypotension and shock: Hallmarks of high-risk central PE with severe hemodynamic compromise 1

Electrocardiographic Findings (More Common in Severe PE)

• Sinus tachycardia: Most common ECG abnormality, present in 40% of cases 5, 2
• T wave inversions in leads V1-V4: Indicates RV strain 5, 1
• S1Q3T3 pattern: Classic but not highly sensitive 5, 1
• QR pattern in lead V1 5, 1
• Right bundle branch block (complete or incomplete) 5, 1
• Atrial arrhythmias, most commonly atrial fibrillation 5, 2

Critical Diagnostic Pitfalls to Avoid

• Do not rule out PE based on normal oxygen saturation: 20-40% of PE patients have normal arterial oxygen saturation (SaO₂) 1, 2, 4
• Do not exclude PE based on absence of chest pain: Approximately 48% of PE patients have no chest pain of any type 2, 4
• Do not dismiss the diagnosis if DVT signs are absent: Only 10-15% of PE patients have clinically apparent leg swelling 2
• Do not rely on a single clinical feature: The predictive value of any individual sign or symptom is less than 80% 1, 2
• Only 3% of PE patients lack all three features of dyspnea, tachypnea, or pleuritic pain—making PE very unlikely when all three are absent 2, 4
• Approximately 20% of patients have a normal alveolar-arterial oxygen gradient 1, 2

Special Clinical Scenarios

• Asymptomatic or incidental PE: Some cases are discovered incidentally during imaging for other conditions 5, 1
• Patients with pre-existing cardiopulmonary disease: Worsening dyspnea may be the sole new symptom, representing a subtle change from baseline 1, 4
• High-risk PE: Defined by persistent hypotension (systolic BP <90 mmHg for ≥15 minutes) or shock, indicating early mortality risk >15% 1, 2

Symptom Patterns Based on PE Location

Central (Large-Vessel) PE

• Acute, severe dyspnea of rapid onset 1, 2, 4
• Substernal chest pain with anginal characteristics 1, 4
• Higher probability of hemodynamic instability 1
• More frequent syncope 1

Peripheral (Small-Vessel) PE

• Mild, sometimes transient dyspnea 1, 4
• Pleuritic chest pain 1, 4
• Hemoptysis 1
• Pleural effusion (usually mild) 1