What is the approach to evaluating chest pain?

Evaluation of Chest Pain

The evaluation of chest pain must prioritize immediate identification of life-threatening causes through a structured approach: obtain an ECG within 10 minutes, measure high-sensitivity cardiac troponins immediately, and use clinical decision pathways to risk-stratify patients for appropriate disposition and testing. 1

Initial Assessment: First 10 Minutes

Immediate Actions

• Obtain a 12-lead ECG within 10 minutes of arrival to identify STEMI, which requires immediate reperfusion therapy 1
• Measure high-sensitivity cardiac troponin as soon as possible after presentation in all patients with suspected acute coronary syndrome 1
• Focus on excluding life-threatening causes: acute coronary syndrome, pulmonary embolism, aortic dissection, tension pneumothorax, cardiac tamponade, and esophageal rupture 1, 2

Recognize Anginal Equivalents

• Chest pain encompasses more than substernal discomfort: pain, pressure, tightness, or discomfort in the shoulders, arms, neck, back, upper abdomen, or jaw all qualify 1
• Shortness of breath and fatigue alone should be considered anginal equivalents, particularly in women and elderly patients 1

History Taking: Critical Features

High-Risk Characteristics

• Sudden onset of severe "ripping" chest or back pain with pulse differential suggests aortic dissection (though pulse differential only present in 30% of cases) 1, 3
• Pleuritic chest pain with dyspnea and tachycardia (present in >90% of cases) suggests pulmonary embolism 1, 3
• Sharp pain that worsens supine and improves sitting forward indicates pericarditis 1, 3

Sex-Specific Presentations

• Women are more likely to present with accompanying symptoms such as nausea, shortness of breath, and fatigue alongside chest pain 1
• Women have higher risk of underdiagnosis, so maintain high suspicion for cardiac causes even with atypical presentations 2

Physical Examination: Key Findings

Life-Threatening Findings

• Diaphoresis, tachypnea, tachycardia, hypotension, crackles, S3 gallop, or new mitral regurgitation murmur suggest acute coronary syndrome (though examination may be normal in uncomplicated cases) 1
• Extremity pulse differential occurs in only 30% of aortic dissections but is highly specific when present 1
• Unilateral absence of breath sounds with hyperresonant percussion indicates pneumothorax 1, 3
• Friction rub with fever and positional chest pain suggests pericarditis 1

Important Caveats

• Chest wall tenderness does NOT exclude acute coronary syndrome: 7% of patients with reproducible chest wall pain still have ACS 3
• Pain relief with nitroglycerin is NOT diagnostic and should never be used to confirm or exclude myocardial ischemia 3

Risk Stratification Algorithm

Low-Risk Patients

• No urgent diagnostic testing needed for patients determined to be low risk through validated clinical decision pathways 1
• Can be safely evaluated in outpatient setting with appropriate follow-up 1

Intermediate-Risk Patients

• Require observation unit management with serial troponins 2
• Proceed to stress testing, coronary CT angiography, or cardiac MRI to exclude obstructive coronary artery disease 1, 2
• These patients benefit most from cardiac imaging and testing 1

High-Risk Patients

• Immediate action required: admit for continuous monitoring and serial biomarkers 2
• If STEMI identified: activate catheterization lab for primary PCI (goal door-to-balloon <90 minutes) or administer fibrinolysis if PCI unavailable 2
• If aortic dissection suspected: administer beta-blockers and vasodilators immediately while arranging definitive imaging 2

Use of Clinical Decision Pathways

Clinical decision pathways must be used routinely in both emergency department and outpatient settings to standardize evaluation and reduce missed diagnoses 1

Structured Risk Assessment Tools

• Apply evidence-based diagnostic protocols to estimate risk for coronary artery disease and adverse events 1
• Avoid the term "atypical chest pain" as it is misleading; use "noncardiac" when heart disease is not suspected 1

Setting-Specific Considerations

Office/Outpatient Setting

• Perform ECG immediately unless a clear noncardiac cause is evident; if ECG unavailable, refer to emergency department 1
• Never delay transfer for troponin testing: patients with suspected ACS must be transported urgently to the ED by EMS 1
• Avoid the dangerous practice of "ruling out" MI in the office with delayed transfer for testing 1

Emergency Department

• ECG acquisition and interpretation within 10 minutes is mandatory 1
• Troponin measurement should occur immediately upon arrival 1
• Use accelerated diagnostic pathways to facilitate efficient evaluation 1

Shared Decision-Making

Engage clinically stable patients in decision-making by discussing risk of adverse events, radiation exposure, costs, and alternative testing options 1

Common Pitfalls to Avoid

• Do not delay ECG interpretation beyond 10 minutes 2
• Do not use nitroglycerin response as a diagnostic test 3
• Do not delay transfer from office for troponin testing 1
• Do not dismiss cardiac causes in women with accompanying symptoms 2
• Do not discount atypical presentations in elderly patients (who may present with dyspnea, syncope, or delirium) 2
• Do not assume pain intensity correlates with severity of underlying disease 2
• Do not assume chest wall tenderness excludes ACS 3

Non-Cardiac Causes to Consider

When cardiac causes are excluded or low probability:

• Musculoskeletal: costochondritis (tenderness at costochondral joints) 1
• Gastrointestinal: GERD, peptic ulcer disease, esophageal spasm 2, 4
• Pulmonary: pneumonia (fever, localized pain, egophony), pleural effusion 1, 3
• Psychiatric: panic disorder, anxiety states 2, 4
• Dermatologic: herpes zoster (dermatomal distribution with characteristic rash) 1