What is the approach to evaluating a patient with chest pain, considering potential cardiac and non-cardiac etiologies, and taking into account their medical history, including cardiovascular disease, hypertension, and hyperlipidemia?

Approach to Chest Pain Evaluation

Begin by obtaining a 12-lead ECG within 10 minutes of patient contact and measuring high-sensitivity cardiac troponin immediately to identify or exclude acute coronary syndrome (ACS), which is the most critical life-threatening diagnosis that must be ruled out first. 1, 2

Immediate Triage and Risk Stratification

The initial assessment must focus on rapidly identifying life-threatening conditions that require immediate intervention:

• Obtain a 12-lead ECG within 10 minutes to identify ST-segment elevation myocardial infarction (STEMI), new left bundle branch block, ST-segment depression, or T-wave inversions indicating ACS 1, 2, 3
• Measure high-sensitivity cardiac troponin as soon as possible to detect myocardial injury with >90% sensitivity and >95% specificity 1, 3
• Assess vital signs immediately, including blood pressure in both arms, heart rate, respiratory rate, and oxygen saturation 2, 4

Life-Threatening Conditions to Rule Out First

The following conditions require immediate recognition and intervention:

• Acute coronary syndrome: Retrosternal pressure/heaviness/squeezing building gradually over minutes, radiating to left arm/neck/jaw, with associated diaphoresis, dyspnea, nausea, or syncope 2, 3
• Aortic dissection: Sudden-onset "ripping" or "tearing" pain radiating to back, with pulse differentials between extremities or new aortic regurgitation murmur 2, 3
• Pulmonary embolism: Acute dyspnea with pleuritic chest pain, tachycardia, and tachypnea 2, 3
• Cardiac tamponade: Hypotension, jugular venous distension, and muffled heart sounds 1
• Tension pneumothorax: Sudden dyspnea, unilateral decreased breath sounds, and tracheal deviation 5

Comprehensive History Taking

Systematically capture six key pain characteristics using a structured approach to differentiate cardiac from non-cardiac causes 1, 2:

Pain Characteristics

High probability of ischemia is indicated by:

• Quality: Pressure, squeezing, gripping, heaviness, tightness, or constriction (not typically described as "pain" by patients) 1, 2
• Location: Central, left-sided, retrosternal, or substernal 1, 2
• Radiation: To neck, jaw, left arm, or shoulders 1, 2
• Onset: Building gradually over several minutes, not instantaneous 2
• Precipitating factors: Exertional or stress-related 1, 2

Low probability of ischemia is indicated by:

• Quality: Sharp, stabbing, fleeting (lasting only seconds), or pleuritic 1, 2
• Location: Localized to very small area or radiating below umbilicus 1, 2
• Duration: Fleeting pain lasting only seconds 2

Associated Symptoms

Document the presence of:

• Dyspnea, diaphoresis, nausea/vomiting, lightheadedness, presyncope, syncope, or palpitations (commonly accompany myocardial ischemia) 2
• Upper abdominal pain or heartburn unrelated to meals (may represent anginal equivalents) 2

Cardiovascular Risk Factors

Systematically assess age, sex, smoking history, diabetes mellitus, hypertension, hyperlipidemia, and family history of premature coronary artery disease 1, 2

Special Population Considerations

Women

Women are at high risk for underdiagnosis and must have potential cardiac causes considered in all presentations 1:

• Women more commonly present with accompanying symptoms including nausea, fatigue, shortness of breath, jaw pain, neck pain, and back pain alongside or instead of classic chest pain 1, 2
• Chest pain is still the dominant symptom for women with ACS, but accompanying symptoms are more frequent 1

Older Adults (≥75 years)

ACS should be considered when accompanying symptoms include shortness of breath, syncope, acute delirium, or unexplained falls, even without classic chest pain 1, 2

Physical Examination

Perform a focused cardiovascular examination immediately to identify complications and aid diagnosis of life-threatening causes 1, 2:

Key Examination Findings by Diagnosis

• ACS: Diaphoresis, tachypnea, tachycardia, hypotension, crackles, S3 gallop, new mitral regurgitation murmur 2
• Aortic dissection: Pulse differential between extremities, blood pressure differential >20 mmHg, new aortic regurgitation murmur 2
• Pulmonary embolism: Tachycardia, tachypnea 2
• Pericarditis: Friction rub, fever 4
• Pneumothorax: Unilateral decreased or absent breath sounds, hyperresonance to percussion 5

Diagnostic Algorithm Based on Risk Stratification

High-Risk Features (Immediate ED Transfer Required)

Transport immediately to ED by EMS (not personal automobile) if any of the following are present 2, 3:

• Prolonged ongoing rest pain (>20 minutes)
• Hemodynamic instability (hypotension, shock)
• New ST-segment changes on ECG
• Elevated troponin above 99th percentile
• New heart failure signs (S3 gallop, crackles)
• Syncope or presyncope with chest pain

Intermediate-Risk Features (Urgent Evaluation Required)

Obtain ECG and troponin urgently, consider ED referral 3:

• Prior history of myocardial infarction or coronary artery disease
• Age >70 years with cardiac-type chest pain
• Diabetes mellitus with chest pain
• Rest angina that has resolved but lasted >20 minutes
• Multiple cardiovascular risk factors

Low-Risk Features (Outpatient Evaluation Acceptable)

For patients determined to be low risk, urgent diagnostic testing for suspected coronary artery disease is not needed 1:

• Atypical chest pain characteristics (sharp, fleeting, pleuritic)
• Pain reproducible by palpation
• No cardiovascular risk factors
• Normal ECG and troponin

Setting-Specific Management

Office/Outpatient Setting

Unless a non-cardiac cause is evident, obtain an ECG; if unavailable, refer patient to ED so one can be obtained 2:

• If clinical evidence of ACS or other life-threatening causes, transport urgently to ED by EMS
• Activating 9-1-1 for transport by EMS rather than self-transport allows for intervention if complications occur en route and reduces in-hospital delay time and mortality 2

Emergency Department Setting

Use clinical decision pathways routinely for chest pain evaluation 1:

• ECG within 10 minutes of arrival 1, 2
• Serial troponin measurements at 0 and 1-3 hours using high-sensitivity assays 1
• Continuous cardiac monitoring for arrhythmias 3
• Risk stratification using validated tools (TIMI, GRACE, HEART scores) 3

Role of Echocardiography

Echocardiography is recommended in specific situations 1:

• Evaluation of acute chest pain with suspected myocardial ischemia/infarction and non-diagnostic ECG and cardiac enzymes when resting echocardiogram can be performed during pain
• Evaluation of chest pain in patients with known underlying cardiac disease (valvular, pericardial, or primary myocardial disease)
• Evaluation of patients with chest pain and hemodynamic instability unresponsive to simple therapeutic measures
• Suspected acute aortic syndromes, pulmonary embolism, myopericarditis, or Takotsubo cardiomyopathy
• Suspected pericardial disease, including effusion, constriction, or bleeding in pericardial space

Echocardiography is NOT recommended 1:

• When non-cardiac etiology is apparent
• In patients with confirmed diagnosis of myocardial ischemia/infarction (diagnosis already established)
• To establish or rule out pulmonary embolism diagnosis (use CT angiography instead)

Critical Terminology

Avoid the term "atypical chest pain" as it is not helpful in determining the cause and can be misinterpreted as benign 1:

• Instead, describe chest pain as cardiac, possibly cardiac, or noncardiac because these terms are more specific to the potential underlying diagnosis 1

Common Pitfalls to Avoid

• Do not rely on nitroglycerin response as a diagnostic criterion, as esophageal spasm and other non-cardiac conditions also respond to nitroglycerin 4, 3
• Do not dismiss chest pain based on young age, as ACS can occur even in adolescents without traditional risk factors 4, 3
• Do not assume sharp or pleuritic pain excludes ACS, as pericarditis and atypical presentations occur 4, 3
• Do not use total CK alone as it is neither sensitive nor specific enough to diagnose or exclude acute myocardial infarction 3
• Do not delay transfer to ED for troponin testing in office settings when ACS is suspected 3

Non-Cardiac Causes to Consider After Excluding Life-Threatening Conditions

Once ACS and other life-threatening conditions are excluded, consider:

• Musculoskeletal: Costochondritis (tenderness of costochondral joints on palpation, pain reproducible by chest wall pressure) 4, 6
• Gastrointestinal: Gastroesophageal reflux disease (burning retrosternal pain, acid regurgitation, sour/bitter taste) 4, 7, 6
• Pulmonary: Pneumonia (fever, localized chest pain, friction rub, regional dullness to percussion) 4, 6
• Psychiatric: Panic disorder or anxiety states (often with hyperventilation, palpitations, sense of impending doom) 7, 6