What is the diagnostic approach and treatment for different types of chest pain, including musculoskeletal (MSK), cardiovascular (Cardio), and pulmonary (Pulm) causes?

Algorithmic Approach to Chest Pain Diagnosis and Management

IMMEDIATE TRIAGE (First 10 Minutes)

Obtain a 12-lead ECG within 10 minutes of patient contact and immediately assess for life-threatening conditions requiring emergency transfer. 1, 2

Life-Threatening Emergencies Requiring Immediate EMS Transfer:

• Acute Coronary Syndrome (ACS): Retrosternal pressure/heaviness building over minutes, radiating to left arm/jaw/neck, with diaphoresis, dyspnea, nausea, or syncope 1, 3, 2

  • ECG shows ST elevation ≥1 mV in contiguous leads, new left bundle branch block, Q waves, or new T-wave inversions 1, 2
  • Give aspirin 160-325 mg immediately unless contraindicated 2

• Aortic Dissection: Sudden-onset "ripping" or "tearing" pain radiating to back, pulse differential between extremities, blood pressure differential >20 mmHg, or new aortic regurgitation murmur 1, 3

  • Severe pain + pulse differential + widened mediastinum on chest X-ray = >80% probability 1

• Pulmonary Embolism: Acute dyspnea with pleuritic chest pain, tachycardia (>90% of patients), tachypnea, with risk factors present 1, 3

• Tension Pneumothorax: Severe dyspnea, unilateral absence of breath sounds, pain with inspiration 1, 3

• Esophageal Rupture: Emesis, subcutaneous emphysema, severe pain, pneumothorax in 20% 1

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CARDIOVASCULAR CAUSES

Acute Coronary Syndrome (STEMI/NSTEMI/Unstable Angina)

Clinical Identification:

• Pain characteristics: Substernal pressure/squeezing/heaviness building gradually over minutes (not seconds), lasting >10 minutes 1, 3
• Radiation pattern: Left arm, jaw, neck, shoulders, or upper abdomen 1
• Triggers: Exertion, emotional stress, or occurring at rest 1
• Associated symptoms: Diaphoresis (key finding), dyspnea, nausea, lightheadedness, syncope 1, 2
• Physical exam: May be completely normal in uncomplicated cases, or show diaphoresis, tachypnea, tachycardia, hypotension, crackles, S3 gallop, new mitral regurgitation murmur 1

High-Risk Populations:

• Women present with more atypical symptoms including nausea, fatigue, and dyspnea without classic chest pain 1, 2
• Age >75 years may present with isolated dyspnea, syncope, acute delirium, or unexplained falls 1, 2
• Diabetics, patients with renal insufficiency, or dementia frequently lack typical symptoms 1

Diagnostic Testing:

• ECG within 10 minutes (Class I recommendation) 1, 2
• Serial ECGs if initial is nondiagnostic and suspicion remains high 1
• Supplemental leads V7-V9 reasonable for posterior MI if initial ECG nondiagnostic 1
• High-sensitivity cardiac troponin as soon as possible (preferred standard) 1, 2
• Chest X-ray to evaluate alternative causes 1

First-Line Treatment:

• Aspirin 160-325 mg orally immediately 2
• Sublingual nitroglycerin if systolic BP >90 mmHg and HR 50-100 bpm 2
• Morphine IV titrated to pain severity 2
• Oxygen only if hypoxemic 2
• Door-to-needle time <30 minutes for thrombolysis or first medical contact to balloon time <90 minutes for PCI 2

Critical Pitfall: Do NOT use nitroglycerin response as a diagnostic criterion—esophageal spasm also responds to nitroglycerin 1, 3, 2

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Other Cardiac Causes

Pericarditis:

• Sharp, pleuritic chest pain worsening when supine, improving when leaning forward 1, 3
• Friction rub on examination (pathognomonic), fever 1
• ECG shows diffuse ST elevation with PR depression 1

Myocarditis:

• Chest pain with fever, signs of heart failure, S3 gallop 1

Valvular Disease:

• Aortic stenosis: Characteristic systolic murmur, tardus/parvus carotid pulse 1
• Aortic regurgitation: Diastolic murmur at right sternal border, rapid carotid upstroke 1
• Hypertrophic cardiomyopathy: Increased/displaced LV impulse, prominent a wave in JVP, systolic murmur 1

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PULMONARY CAUSES

Pulmonary Embolism

Clinical Identification:

• Acute dyspnea with pleuritic chest pain (sharp, worse with inspiration) 1, 3
• Tachycardia present in >90% of patients 1
• Risk factors: immobilization, recent surgery, malignancy, pregnancy, oral contraceptives 3

Diagnostic Testing:

• D-dimer if low-to-intermediate probability 4
• CT pulmonary angiography (gold standard) 4

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Pneumonia

Clinical Identification:

• Fever, localized chest pain (may be pleuritic), friction rub may be present 1
• Regional dullness to percussion, egophony 1, 5

Diagnostic Testing:

• Chest X-ray 1
• Consider sputum culture and blood cultures if severe 5

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Pneumothorax

Clinical Identification:

• Dyspnea and pain with inspiration, unilateral absence of breath sounds 1, 3

Diagnostic Testing:

• Chest X-ray (upright preferred) 1

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MUSCULOSKELETAL CAUSES

Costochondritis/Tietze Syndrome

Clinical Identification:

• Tenderness of costochondral joints on palpation (diagnostic) 1, 3
• Pain reproducible with chest wall pressure 3
• Pain localized to very limited area 1, 3
• Affected by palpation, breathing, turning, twisting, or bending 3
• Sharp, stabbing quality lasting seconds to minutes 3

Diagnostic Testing:

• No testing required if classic presentation 3
• ECG only if any cardiac risk factors or atypical features present 3

First-Line Treatment:

• NSAIDs (ibuprofen 400-600 mg TID or naproxen 500 mg BID) 5
• Reassurance and activity modification 5

Critical Pitfall: Pain radiating below the umbilicus or to the hip is unlikely to be ischemic 1

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GASTROINTESTINAL CAUSES

Gastroesophageal Reflux Disease (GERD)/Esophagitis

Clinical Identification:

• Burning retrosternal pain related to meals, relieved by antacids 1, 3
• Acid regurgitation, sour or bitter taste in mouth 5
• Epigastric tenderness on examination 1

Diagnostic Testing:

• Trial of proton pump inhibitor (diagnostic and therapeutic) 5
• Upper endoscopy if alarm symptoms (dysphagia, weight loss, anemia) 5

First-Line Treatment:

• Proton pump inhibitor (omeprazole 20 mg daily or equivalent) for 4-8 weeks 5

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Peptic Ulcer Disease/Gallbladder Disease

Clinical Identification:

• Epigastric or right upper quadrant tenderness 1
• Murphy sign (inspiratory arrest with RUQ palpation) suggests cholecystitis 1

Diagnostic Testing:

• Right upper quadrant ultrasound for gallbladder disease 5
• Upper endoscopy for peptic ulcer disease 5

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DIAGNOSTIC ALGORITHM FLOWCHART

Step 1: Obtain ECG Within 10 Minutes 1, 2

If ECG shows STEMI or new ischemic changes: → Immediate EMS transfer, aspirin 160-325 mg, activate catheterization lab 2

If ECG nondiagnostic but high clinical suspicion: → Serial ECGs, high-sensitivity troponin, consider supplemental leads V7-V9 1

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Step 2: Assess for Life-Threatening Features 3, 2

Present:

• Hemodynamic instability (hypotension, shock)
• Pulse differential or BP differential
• Sudden-onset tearing pain
• Severe dyspnea with unilateral absent breath sounds

→ Immediate EMS transfer 2

Absent: → Proceed to Step 3

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Step 3: Characterize Pain Quality and Associated Symptoms 1, 3

Retrosternal pressure/heaviness + radiation to left arm/jaw + diaphoresis: → ACS pathway: Troponin, serial ECGs, cardiology consultation 2

Sharp pleuritic pain + fever + positional (worse supine): → Pericarditis: ECG (diffuse ST elevation), echocardiogram, inflammatory markers 1

Acute dyspnea + pleuritic pain + tachycardia + risk factors: → PE pathway: D-dimer, CT pulmonary angiography 4

Tenderness of costochondral joints + reproducible with palpation: → Costochondritis: No further testing needed, NSAIDs 3, 5

Burning retrosternal pain + meal-related + relieved by antacids: → GERD: PPI trial 5

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Step 4: Risk Stratification for Intermediate Cases 1

Use Marburg Heart Score or INTERCHEST clinical decision rule 4

Low risk:

• No urgent testing needed 1
• Outpatient follow-up appropriate 4

Intermediate risk:

• Exercise stress testing, coronary CT angiography, or cardiac MRI 4

High risk:

• Hospital admission for serial troponins and observation 1

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SPECIAL POPULATION CONSIDERATIONS

Women:

• Emphasize accompanying symptoms (nausea, fatigue, dyspnea) over classic chest pain 1, 2
• Higher risk of underdiagnosis 1

Age >75 years:

• Consider ACS with isolated dyspnea, syncope, acute delirium, or unexplained falls 1, 2

Diabetics:

• Frequently present without typical symptoms 1

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CRITICAL PITFALLS TO AVOID

1. Do NOT delay transfer for troponin testing in office settings when ACS suspected 2
2. Do NOT use nitroglycerin response as diagnostic criterion 1, 3
3. Do NOT assume young age excludes ACS 2
4. Do NOT dismiss chest pain in women or elderly with atypical symptoms 1, 2
5. Do NOT rely on physical examination alone—it contributes almost nothing to diagnosing MI unless shock present 2
6. Sharp, pleuritic pain does NOT exclude ACS—pericarditis and atypical presentations occur 1, 2
7. Point tenderness makes ischemia less likely but does not exclude it 1