What is the appropriate initial assessment and management for a patient presenting with chest pain?

Initial Assessment and Management of Chest Pain

Obtain a 12-lead ECG within 10 minutes of arrival and draw high-sensitivity cardiac troponin immediately to identify or exclude life-threatening conditions—acute coronary syndrome, aortic dissection, pulmonary embolism, tension pneumothorax, cardiac tamponade, and esophageal rupture. 1

Immediate Actions (First 10 Minutes)

• Activate emergency medical services (EMS) for transport if the patient is not already in the emergency department; personal automobile transport should be avoided because EMS can perform pre-hospital ECG, administer aspirin, provide defibrillation, and reduce travel time. 1

• Measure vital signs promptly including heart rate, blood pressure in both arms (to detect pulse differentials suggesting aortic dissection), respiratory rate, and oxygen saturation. 1

• Administer aspirin 162–325 mg (chewed, not swallowed) immediately in alert adults without known allergy or active gastrointestinal bleeding while awaiting further evaluation. 1, 2

• Give sublingual nitroglycerin unless systolic blood pressure is <90 mmHg or heart rate is <50 bpm or >100 bpm, but recognize that nitroglycerin response does not differentiate cardiac from non-cardiac pain (esophageal spasm may also respond). 1, 3

• Provide intravenous morphine 4–8 mg (with additional 2 mg doses every 5 minutes as needed) for pain relief, because pain increases sympathetic activation and myocardial oxygen demand. 1

• Supply supplemental oxygen 2–4 L/min only if the patient is breathless, shows heart-failure features, or has oxygen saturation <90%; routine oxygen in normoxemic patients may be harmful. 1

Critical History Elements to Document

Pain Characteristics That Increase ACS Likelihood

• Quality: Retrosternal pressure, squeezing, gripping, heaviness, or tightness (patients rarely use the word "pain" itself); sharp, stabbing, or pleuritic pain does not exclude ACS—13% of patients with pleuritic features have myocardial ischemia. 1, 3

• Onset: Builds gradually over several minutes, not instantaneously; sudden "ripping" or "tearing" pain maximal at onset suggests aortic dissection. 1

• Radiation: Left arm, neck, jaw, or between shoulder blades increases cardiac probability; radiation below the umbilicus or to a very small localized area is unlikely to be ischemic. 1, 3

• Duration: Typical anginal symptoms last several minutes; fleeting pain lasting only seconds is unlikely to be ischemic; ongoing rest pain >20 minutes is high-risk. 1, 3

• Precipitating factors: Physical exertion or emotional stress commonly trigger anginal episodes. 1

Associated Symptoms That Significantly Raise ACS Probability

• Dyspnea or shortness of breath, diaphoresis, nausea or vomiting, lightheadedness, presyncope, or syncope. 1, 3

Cardiovascular Risk Factors to Assess

• Age, sex, diabetes mellitus, hypertension, hyperlipidemia, smoking, and family history of premature coronary artery disease. 1

Focused Cardiovascular Examination

• Look for high-risk findings: Diaphoresis, tachypnea, tachycardia (>100 bpm) or bradycardia (<50 bpm), hypotension (systolic BP <100 mmHg), pulmonary crackles, S3 gallop, new murmurs (mitral regurgitation suggesting papillary-muscle dysfunction or aortic regurgitation suggesting dissection), pericardial friction rub, unilateral absent breath sounds (pneumothorax), subcutaneous emphysema (esophageal rupture), pulse differential between extremities (aortic dissection), and jugular venous distension (tamponade or heart failure). 1, 2

• Recognize that a completely normal physical examination does not exclude acute myocardial infarction; uncomplicated MI can present with entirely unremarkable findings. 1

ECG Interpretation Within 10 Minutes

• STEMI: ST-segment elevation ≥1 mm in contiguous leads mandates immediate activation of reperfusion protocol—primary PCI with door-to-balloon <90 minutes (preferred) or fibrinolysis with door-to-needle <30 minutes. 1, 2

• NSTE-ACS: ST-segment depression ≥1 mm or T-wave inversions require admission to coronary care unit, continuous cardiac monitoring, dual antiplatelet therapy (aspirin + P2Y12 inhibitor), anticoagulation, and urgent coronary angiography. 1, 2

• Pericarditis pattern: Diffuse concave ST-elevation with PR-segment depression. 1

• If initial ECG is nondiagnostic but clinical suspicion remains high: Obtain serial ECGs every 15–30 minutes and consider posterior leads V7–V9 to detect evolving ischemic changes. 1, 2

• Critical caveat: A normal ECG does not exclude ACS—30–40% of acute myocardial infarctions present with a normal or nondiagnostic ECG. 1

Cardiac Troponin Strategy

• High-sensitivity troponin is the most sensitive and specific biomarker for myocardial injury; measure immediately when ACS is suspected. 1, 2, 3

• Repeat measurement: At 1–3 hours after the initial sample when using high-sensitivity assays, or at 3–6 hours when using conventional assays. 1

• Single-sample rule-out: In patients with symptom onset ≥3 hours before presentation, a normal ECG, and high-sensitivity troponin below the limit of detection, a single measurement reliably excludes myocardial injury. 1

• Sex-specific thresholds: Use >16 ng/L for women and >34 ng/L for men to avoid missing STEMI in women; universal cutoffs misclassify ~30% of women. 1

Risk Stratification and Disposition

High-Risk Features Mandating Immediate Coronary Care Unit Admission

• Ongoing rest pain >20 minutes, hemodynamic instability (systolic BP <100 mmHg, heart rate >100 bpm or <50 bpm), severe continuing pain with ischemic ECG changes, troponin above the 99th percentile, or evidence of left-ventricular failure (crackles, S3 gallop, new murmurs). 1

Intermediate-Risk Features

• Age >70 years (or ≥75 years with dyspnea, syncope, delirium, or unexplained falls), prior myocardial infarction or known coronary artery disease, diabetes, hypertension, hyperlipidemia, smoking, or rest angina >20 minutes that has resolved. 1

Low-Risk Criteria for Chest-Pain Unit Observation or Early Discharge

• Normal or nondiagnostic ECG, negative troponin at presentation and at 6–12 hours after symptom onset, stable vital signs, no ongoing chest discomfort, and no clinical evidence of heart failure. 1

• Management: Observe in a chest-pain unit for 10–12 hours or discharge for outpatient stress testing within 72 hours. 1

Life-Threatening Differential Diagnoses

Acute Aortic Dissection

• Presentation: Sudden, severe "ripping" or "tearing" chest or back pain maximal at onset. 1

• Physical clues: Pulse differential between extremities (~30% of cases), systolic BP difference >20 mmHg between arms, new aortic-regurgitation murmur (40–75% of type A dissections). 1

• Management: Withhold antithrombotic therapy (aspirin, heparin) if dissection is suspected; transfer immediately to a center with 24/7 aortic imaging and cardiac surgery capability. 1

Pulmonary Embolism

• Presentation: Sudden dyspnea with pleuritic chest pain that worsens on inspiration. 1

• Physical findings: Tachycardia (present in >90% of patients) and tachypnea. 1

• Risk stratification: Apply Wells criteria; in low-to-intermediate probability patients, obtain an age- and sex-adjusted D-dimer—a negative result effectively rules out PE. 1

• Imaging: Proceed directly to CT pulmonary angiography when clinical suspicion is high or D-dimer is positive. 1

Tension Pneumothorax

• Physical findings: Unilateral absent or markedly reduced breath sounds, hyperresonant percussion, tracheal deviation, hypotension, tachycardia. 1

Cardiac Tamponade

• Presentation: Pleuritic chest pain that worsens when supine. 1

• Physical findings: Jugular venous distension, signs of cardiogenic shock (HR >130 bpm or <40 bpm, SBP <90 mmHg), respiratory distress (RR >25, SpO₂ <90%), low-voltage ECG or electrical alternans. 1

Esophageal Rupture (Boerhaave Syndrome)

• History: Forceful vomiting preceding chest pain. 1

• Findings: Subcutaneous emphysema, pneumothorax in ~20% of patients, unilateral decreased or absent breath sounds. 1

Special Population Considerations

Women

• Higher risk of underdiagnosis; more frequently present with accompanying symptoms (jaw/neck pain, nausea/vomiting, epigastric discomfort, fatigue, dyspnea, back pain, palpitations) rather than classic chest pain. 1, 3

• Use sex-specific troponin thresholds to avoid missing STEMI. 1

• Actively inquire about accompanying symptoms during assessment. 1

Older Adults (≥75 Years)

• May present atypically with isolated dyspnea, syncope, acute delirium, or unexplained falls without classic chest pain; maintain a high index of suspicion for ACS in this group. 1, 3

Patients with Diabetes

• More likely to present with atypical symptoms including vague abdominal symptoms, confusion, or isolated dyspnea; higher risk for silent ischemia. 1

Critical Pitfalls to Avoid

• Do not rely on nitroglycerin response to differentiate cardiac from non-cardiac chest pain; esophageal spasm and other conditions may also improve. 1, 3

• Do not delay EMS transport for troponin testing in office or outpatient settings when ACS or another life-threatening cause is suspected; arrange urgent EMS transport without awaiting additional testing. 1, 2, 3

• Do not dismiss chest pain in women, older adults, or patients with diabetes based on atypical presentations; these groups frequently lack classic symptoms. 1

• Do not assume young age excludes ACS; it can occur even in adolescents without traditional risk factors. 1, 3

• Avoid the term "atypical chest pain"; instead describe presentations as "cardiac," "possibly cardiac," or "non-cardiac" to prevent misinterpretation as benign. 1, 2, 3

• A normal physical examination does not exclude ACS; uncomplicated myocardial infarction can present with a completely normal exam. 1

• A normal initial ECG does not rule out ACS; 30–40% of acute myocardial infarctions present with a normal or nondiagnostic ECG. 1

• Sharp, pleuritic pain does not exclude ACS; pericarditis and atypical presentations can occur, and ~13% of patients with pleuritic features have myocardial ischemia. 1, 3

Setting-Specific Recommendations

Office/Outpatient Setting

• If an ECG cannot be obtained on site, refer the patient to the emergency department immediately for ECG acquisition. 1, 2

• When clinical evidence of ACS or another life-threatening cause exists, arrange urgent EMS transport; do not postpone transfer for troponin or other diagnostics. 1, 2, 3

Emergency Department

• Utilize clinical decision pathways (e.g., TIMI, GRACE scores) routinely for chest-pain evaluation. 1

• Engage in shared decision-making with clinically stable patients regarding testing options, considering radiation exposure and cost. 1

• Consider bedside two-dimensional echocardiography to detect regional wall motion abnormalities and to exclude aortic dissection, pericardial effusion, or pulmonary embolism. 1, 4