What is the differential diagnosis for an adult patient with no prior medical history presenting with chest pain?

Differential Diagnosis for Chest Pain in Adults

Immediate Life-Threatening Causes (Must Exclude First)

The American College of Cardiology and European Heart Society mandate immediate exclusion of life-threatening conditions: acute coronary syndrome, aortic dissection, pulmonary embolism, tension pneumothorax, pericarditis, and esophageal rupture. 1, 2

Acute Coronary Syndrome (ACS)

• Presentation: Retrosternal pressure, heaviness, or squeezing that builds gradually over minutes (not seconds), radiating to left arm, jaw, or neck 1, 2
• Associated symptoms: Diaphoresis, dyspnea, nausea, or syncope 2
• Key features: Pain occurs at rest or with minimal exertion, lasts >10 minutes 2
• Prevalence: Accounts for 20% of chest pain in general practice, 45-60% in emergency settings 3

Aortic Dissection

• Presentation: Sudden-onset "ripping" or "tearing" chest or back pain 1, 2
• Physical findings: Pulse differentials between extremities, blood pressure differential >20 mmHg between arms, new aortic regurgitation murmur 4, 2
• Critical feature: Abrupt onset distinguishes this from gradual ACS pain 5

Pulmonary Embolism

• Presentation: Acute dyspnea with pleuritic chest pain 1, 2
• Physical findings: Tachycardia (present in >90% of cases), tachypnea 2
• Risk stratification: Use Wells score or Geneva score with D-dimer and age-adjusted cutoffs 1

Tension Pneumothorax

• Presentation: Severe dyspnea and pain on inspiration 4
• Physical findings: Unilateral decreased or absent breath sounds 1, 4
• Key feature: Acute onset with respiratory distress 2

Acute Pericarditis

• Presentation: Sharp, pleuritic chest pain that worsens when supine and improves when leaning forward 1, 4, 2
• Physical findings: Pericardial friction rub (may be audible), fever 1, 4
• ECG findings: Widespread ST-elevation and PR depression 1

Esophageal Rupture

• Presentation: History of recent emesis, severe chest pain 4
• Physical findings: Subcutaneous emphysema, pneumothorax, unilateral decreased breath sounds 4

Serious But Non-Immediately Fatal Causes

Myocarditis

• Presentation: Chest pain with fever 4, 2
• Physical findings: Signs of heart failure, S3 gallop 4, 2
• Laboratory: Markedly elevated troponin (can exceed 15,000 ng/L in young patients) 6

Pneumonia

• Presentation: Chest pain related to respiratory infection, fever, productive cough 7
• Key feature: Pain associated with breathing movements 7

Common Benign Causes

Musculoskeletal (Costochondritis/Chest Wall Pain)

• Prevalence: Accounts for 43% of chest pain in general practice 3
• Presentation: Tenderness of costochondral joints reproducible on palpation 1, 4, 2
• Key features: Pain affected by palpation, breathing, turning, twisting, or bending; localized to very limited area 2
• Critical caveat: 7% of patients with reproducible chest wall pain may still have ACS 1

Gastroesophageal Reflux Disease (GERD)

• Presentation: Burning retrosternal pain, acid regurgitation, sour or bitter taste 1, 2
• Key features: Postprandial timing, relieved by antacids 2

Psychiatric Causes

• Prevalence: Accounts for 11% in general practice, 8% in emergency departments 3
• Associated conditions: Anxiety, depression, alcohol abuse 3
• Key feature: Fleeting pain lasting only seconds is unlikely to be cardiac 4

Critical Pitfalls to Avoid

Do not use nitroglycerin response as a diagnostic criterion—esophageal spasm and other non-cardiac conditions also respond to nitroglycerin. 4, 2

Do not dismiss chest pain in women, elderly patients, or patients with diabetes—they frequently present with atypical symptoms including sharp or positional pain. 4, 2

Do not delay transfer for troponin testing in the office setting if high-risk features are present. 2, 8

Mandatory Initial Evaluation Algorithm

Step 1: Obtain 12-lead ECG within 10 minutes

• Look for: STEMI, new left bundle branch block, Q waves, T wave inversions, pericarditis patterns (widespread ST elevation with PR depression) 1, 2
• Action: If ST-elevation or new ischemic changes present, treat as STEMI and transport by EMS immediately 2

Step 2: Measure cardiac troponin immediately

• Indication: All patients with acute chest pain and any suspicion of ACS, even if pleuritic characteristics make ischemia less likely 1, 2
• Interpretation: Very high troponin levels (>15,000 ng/L) in young patients suggest myopericarditis rather than ACS 6

Step 3: Obtain chest radiography

• Indications: Evaluate for pneumothorax, pneumonia, pleural effusion, widened mediastinum 1
• Limitation: Normal results occur in 11-62% of certain conditions 1

Step 4: Risk stratification for specific conditions

• For pulmonary embolism: Wells or Geneva score with D-dimer; CT pulmonary angiogram if high probability or elevated D-dimer 1
• For aortic dissection: D-dimer <500 ng/mL makes dissection unlikely 2

High-Risk Features Requiring Immediate Emergency Transfer

• Age >75 years with accompanying dyspnea, syncope, acute delirium, or unexplained fall 4, 2
• Hemodynamic instability 2
• New ECG abnormalities 2
• Elevated cardiac troponin with concerning clinical features 4
• Pulse or blood pressure differentials >20 mmHg 4
• New cardiac murmurs 4