What is the appropriate management for a patient with chest pain?

Management of Chest Pain

Obtain a 12-lead ECG within 10 minutes of patient arrival and immediately administer aspirin 160-325 mg (chewed) unless contraindicated, while simultaneously assessing for life-threatening conditions including acute coronary syndrome, aortic dissection, and pulmonary embolism. 1, 2

Immediate Assessment (First 5-10 Minutes)

Life-threatening differentials must be identified immediately:

• Acute coronary syndrome: retrosternal discomfort building over minutes, radiating to left arm/neck/jaw, with dyspnea, nausea, or diaphoresis 1
• Acute aortic syndromes: sudden-onset tearing/ripping pain with back radiation 1
• Pulmonary embolism: sudden dyspnea with pleuritic chest pain in patients with risk factors 1
• Pneumothorax and acute pericarditis: less common but life-threatening 3

Mandatory initial actions:

• Record and interpret 12-lead ECG within 5-10 minutes of first contact 3, 1, 2
• Draw cardiac troponin (T or I) and CK-MB mass immediately on arrival 3, 2
• Assess vital signs for hemodynamic instability: heart rate <40 or >100/min, systolic BP <100 or >200 mmHg, cold extremities 2
• Perform focused cardiovascular examination for diaphoresis, tachypnea, crackles, S3 gallop, or new murmurs 1

Immediate Medical Interventions

Administer these medications without delay:

• Aspirin 160-325 mg (chewed, not swallowed) as soon as possible unless contraindicated by known allergy or active GI bleeding 1, 2, 4
• Intravenous morphine 4-8 mg with additional 2 mg doses every 5 minutes for pain relief, as pain increases sympathetic activation and myocardial workload 2
• Sublingual nitroglycerin unless systolic BP <90 mmHg or heart rate <50 or >100 bpm 2, 4
• Oxygen 2-4 L/min if patient is breathless, has heart failure features, or oxygen saturation is low 2

Risk Stratification Based on ECG and Clinical Features

High-risk patients requiring immediate coronary care unit admission: 3, 2

• ST-segment elevation ≥1 mV in contiguous leads (indicates thrombotic coronary occlusion requiring immediate reperfusion)
• Severe continuing pain with ischemic ECG changes
• Positive troponin test
• Left ventricular failure or hemodynamic abnormalities
• Recurrent ischemia or major arrhythmias

For STEMI identified on ECG:

• Door-to-needle time for thrombolysis must be <30 minutes OR
• First medical contact to balloon time <90 minutes (preferred; <120 minutes acceptable) 1
• Pre-hospital thrombolysis reduces mortality by 17%, saving 23 lives per 1000 per hour of earlier treatment 1

Intermediate-risk features: 2

• Prior history of MI or coronary artery disease
• Age >70 years
• Diabetes mellitus
• Rest angina >20 minutes that has resolved

Serial Biomarker Testing

Repeat cardiac troponin at 10-12 hours after symptom onset for diagnosis of possible myocardial infarction and risk assessment 3, 2

• Total CK alone is neither sensitive nor specific enough to diagnose or exclude acute MI 2
• High-sensitivity cardiac troponin (hs-cTn) is more sensitive and specific than CK or CK-MB for detecting myocardial injury 2

Special Population Considerations

Women are at risk for underdiagnosis:

• Emphasize accompanying symptoms like nausea, fatigue, dyspnea, arm pain, jaw pain, and epigastric discomfort 1, 2

Older adults (≥75 years) may present atypically:

• Consider ACS with isolated dyspnea, syncope, acute delirium, or unexplained falls without classic chest pain 1

Young patients:

• Do not assume young age excludes ACS—it can occur in adolescents without risk factors 1

Chest Pain Unit Management for Low-to-Intermediate Risk Patients

Patients with normal ECG and negative initial troponin require observation: 3, 2, 5, 6

• Observe for 10-12 hours after symptom onset in chest pain unit
• Equip unit with resuscitation capabilities, cardiac rhythm monitoring, and continuous ST-segment monitoring
• Repeat troponin at 6-12 hours
• Consider stress testing before discharge if both troponins remain negative
• This approach is safe, effective, and cost-saving compared to routine hospitalization

The risk of discharging patients without proper observation is substantial:

• Without proper evaluation, 20-30% of unstable angina patients either died or had MI within 4 weeks in the pre-aspirin/pre-heparin era 3
• Current risk with appropriate management is 8% 3

Critical Pitfalls to Avoid

• Do not rely on nitroglycerin response as diagnostic for ACS—esophageal spasm and other conditions may also respond 1
• Do not delay ED transfer for troponin testing in office settings when ACS is suspected 1
• Sharp, pleuritic pain does not exclude ACS—pericarditis and atypical presentations can occur 1
• Do not use total CK as the sole marker for detecting myocardial injury 2
• Physical examination contributes almost nothing to diagnosing MI unless shock is present 1

Transport Decisions

Call ambulance immediately for suspected ACS rather than attempting office-based evaluation:

• EMS transport allows for intervention if complications occur en route 1
• Pre-hospital ECG use reduces in-hospital delay time and mortality 1