What is the differential diagnosis and management for chest pain?

Differential Diagnosis for Chest Pain

Life-Threatening Causes Requiring Immediate Recognition

The initial evaluation must rapidly identify life-threatening conditions including acute coronary syndrome (ACS), aortic dissection, pulmonary embolism, tension pneumothorax, and esophageal rupture before considering benign etiologies. 1, 2

Acute Coronary Syndrome (STEMI/NSTEMI/Unstable Angina)

• Presentation: Retrosternal pressure, heaviness, or squeezing that builds gradually over several minutes (not seconds), radiating to left arm, jaw, or neck 1, 2
• Associated symptoms: Diaphoresis, dyspnea, nausea, lightheadedness, or syncope—particularly common in women, elderly, and diabetic patients 1
• Physical exam: May be completely normal in uncomplicated cases; look for diaphoresis, tachypnea, tachycardia, hypotension, crackles, S3 gallop, or new mitral regurgitation murmur 1
• Critical pitfall: Atypical presentations (sharp pain, reproducible pain, positional pain) occur frequently in women, elderly, and diabetic patients—never dismiss based on pain character alone 3, 2

Aortic Dissection

• Presentation: Sudden-onset "ripping" or "tearing" chest or back pain with maximal intensity at onset 1, 2
• Physical exam: Pulse differential between extremities (30% of patients), blood pressure differential >20 mmHg, new aortic regurgitation murmur (40-75% in type A), syncope (>10%) 1, 4
• Risk factors: Connective tissue disorders (Marfan syndrome), hypertension, atherosclerosis, prior aortic procedures 1, 5
• Imaging clue: Widened mediastinum on chest X-ray combined with severe abrupt pain and pulse differential yields >80% probability 1

Pulmonary Embolism

• Presentation: Acute dyspnea with pleuritic chest pain (pain worsens with inspiration) 1, 2
• Physical exam: Tachycardia and dyspnea present in >90% of patients, tachypnea 1, 4
• Key feature: Pain increases with inspiration, associated with risk factors for thromboembolism 6

Tension Pneumothorax

• Presentation: Dyspnea and sharp pain on inspiration 1, 4
• Physical exam: Unilateral absence of breath sounds, hyperresonant percussion, tracheal deviation in severe cases 1, 3
• Context: May occur spontaneously (primary spontaneous pneumothorax) or follow trauma 6

Esophageal Rupture

• Presentation: Severe chest pain following emesis 1, 4
• Physical exam: Subcutaneous emphysema, pneumothorax (20% of patients), unilateral decreased or absent breath sounds 1
• Critical feature: Painful tympanic abdomen indicates potentially life-threatening gastrointestinal etiology 1

Serious Non-Immediately Fatal Cardiac Causes

Pericarditis

• Presentation: Sharp, pleuritic chest pain that worsens when supine and improves when sitting forward or leaning forward 1, 3, 2
• Physical exam: Friction rub (pathognomonic but not always present), fever 1, 4
• ECG findings: Widespread ST elevation with PR depression 3

Myocarditis

• Presentation: Chest pain with fever and signs of heart failure 1, 3
• Physical exam: S3 gallop, signs of heart failure 1, 4
• Pitfall: Can mimic musculoskeletal pain or ACS 3

Valvular Heart Disease

• Aortic stenosis: Characteristic systolic murmur, tardus or parvus carotid pulse 1
• Aortic regurgitation: Diastolic murmur at right of sternum, rapid carotid upstroke 1
• Hypertrophic cardiomyopathy: Increased or displaced left ventricular impulse, prominent a wave in jugular venous pressure, systolic murmur 1

Pulmonary Causes

Pneumonia

• Presentation: Localized chest pain, may be pleuritic 1, 3
• Physical exam: Fever, friction rub may be present, regional dullness to percussion, egophony 1, 4
• Context: Pain associated with respiratory infection rarely poses difficult diagnostic problem 6

Pleurisy

• Presentation: Intensely painful but prognostically benign; pain related to breathing movements 6
• Key feature: Pleuritic character (worsens with inspiration) differentiates from constant pain of malignancy 6

Common Benign Causes

Costochondritis/Tietze Syndrome

• Presentation: Localized chest wall pain, affected by palpation, breathing, turning, twisting, or bending 1, 2
• Physical exam: Tenderness of costochondral joints on palpation, pain reproducible with chest wall pressure 1, 3, 4
• Critical caveat: Reproducible chest wall tenderness has 98.1% negative predictive value for ACS, but approximately 7% of patients with reproducible pain still have ACS—ECG and troponin remain mandatory 3

Gastroesophageal Reflux Disease/Esophagitis

• Presentation: Burning retrosternal pain related to meals, relieved by antacids 2
• Physical exam: Epigastric tenderness 1
• Pitfall: Nitroglycerin response is NOT diagnostic of cardiac ischemia—esophageal spasm also responds to nitroglycerin 1, 3, 4

Herpes Zoster

• Presentation: Pain in dermatomal distribution triggered by touch 1, 3
• Physical exam: Characteristic unilateral dermatomal rash (may appear after pain onset) 1, 4

Mandatory Initial Evaluation Algorithm

Step 1: Immediate Assessment (Within 10 Minutes)

• Obtain 12-lead ECG within 10 minutes of arrival to any medical facility, regardless of pain characteristics, unless clearly noncardiac cause is evident 1, 3
• If STEMI or new LBBB: Activate immediate reperfusion protocol (primary PCI within 120 minutes or thrombolysis if PCI unavailable) 1, 5
• If ST-T abnormalities suggesting ischemia: Urgent hospital evaluation required 1, 3

Step 2: Focused History

• Pain characteristics: Onset (gradual over minutes vs. sudden), duration, quality (pressure/squeezing vs. sharp/stabbing), location, radiation pattern 1, 2
• Precipitating factors: Exertion, emotional stress, meals, position changes, breathing 1, 2
• Associated symptoms: Dyspnea, diaphoresis, nausea, syncope, fever 1
• Cardiovascular risk factors: Age, diabetes, hypertension, hyperlipidemia, smoking, family history 1

Step 3: Focused Physical Examination

• Vital signs: Blood pressure in both arms (differential >20 mmHg suggests dissection), heart rate, respiratory rate 1, 4
• Cardiovascular exam: Murmurs, S3 gallop, friction rub, pulse differentials 1, 4
• Pulmonary exam: Breath sounds (unilateral absence suggests pneumothorax), percussion, egophony 1, 3
• Chest wall exam: Reproducible tenderness (does NOT rule out ACS) 3

Step 4: Cardiac Biomarkers

• Measure cardiac troponin as soon as possible after presentation in any patient with acute chest pain and suspected ACS 1, 3
• Critical error to avoid: Do NOT delay transfer from office to ED for troponin testing—transport urgently by EMS if ACS suspected 1, 3

Setting-Specific Management

Office/Primary Care Setting

• If any clinical evidence of ACS or life-threatening cause: Transport urgently to ED by EMS (NOT personal automobile) 1
• If stable with suspected cardiac cause: Obtain ECG; if unavailable, refer to ED immediately 1
• Pre-hospital treatment while awaiting EMS: Aspirin (chewable or water-soluble), short-acting nitrate if no bradycardia or hypotension, opiates for pain relief 1
• Stay with patient until EMS arrives if heart attack suspected 1

Emergency Department Setting

• ECG within 10 minutes and troponin measurement as soon as possible are mandatory 1, 3
• Risk stratification: Use GRACE 2.0 or TIMI risk scores for ACS patients to determine timing of invasive management 5
• Additional imaging: Consider chest X-ray, echocardiography, or CT angiography based on differential diagnosis 3

High-Risk Features Requiring Immediate Action

• Age >75 years with accompanying dyspnea, syncope, acute delirium, or unexplained fall 2, 4
• Women, elderly, diabetic patients, or those with renal insufficiency/dementia presenting with atypical symptoms 2
• Pulse differentials, blood pressure differentials >20 mmHg, or new murmurs 1, 4
• Elevated cardiac troponin levels 4

Features Suggesting Non-Cardiac Etiology (But NOT Definitive)

• Fleeting pain lasting only seconds 1, 4
• Pain localized to very small area or radiating below umbilicus 2
• Pain affected by palpation, breathing, turning, twisting, or bending 1, 2
• Pain generated from multiple sites 1

Critical caveat: These features reduce but do not eliminate cardiac risk—ECG and troponin remain mandatory before safely ruling out cardiac causes. 3