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

Initial Evaluation and Management of Chest Pain

Obtain a 12-lead ECG within 10 minutes of patient arrival and measure cardiac troponin as soon as possible in any patient with suspected cardiac chest pain. 1, 2, 3

Immediate Life-Threatening Assessment (First 10 Minutes)

The priority is identifying conditions that kill: acute coronary syndrome (ACS), acute aortic syndromes, and pulmonary embolism. 2

ECG Acquisition and Interpretation

• Acquire and interpret a 12-lead ECG within 10 minutes of first patient contact, regardless of setting. 1, 2, 3, 4
• If ST-segment elevation ≥1 mm in contiguous leads is present, immediately activate STEMI protocols (door-to-balloon <90 minutes preferred, or door-to-needle <30 minutes for thrombolysis). 1, 2
• If ST-depression or new T-wave inversions are present, treat according to NSTE-ACS guidelines. 1, 4
• Perform serial ECGs every 15-30 minutes if initial ECG is nondiagnostic but clinical suspicion remains high, symptoms persist, or clinical condition deteriorates. 1, 3, 4
• Consider supplemental leads V7-V9 in patients with intermediate-to-high ACS suspicion and nondiagnostic initial ECG to detect posterior MI. 1, 3

Cardiac Biomarkers

• Measure high-sensitivity cardiac troponin (hs-cTn) immediately upon presentation when ACS is suspected—this is the preferred biomarker over conventional troponin. 1, 2, 3, 4
• Repeat troponin at 1-3 hours for high-sensitivity assays or 3-6 hours for conventional assays. 3
• For patients with symptoms beginning ≥3 hours before arrival, a single hs-cTn below the limit of detection at time zero is reasonable to exclude myocardial injury. 3

Critical History Elements to Obtain

Focus on specific discriminating features rather than generic descriptions:

Pain Characteristics

• Exact location and radiation pattern (retrosternal with radiation to left arm/neck/jaw suggests ACS; sudden tearing pain radiating to back suggests aortic dissection). 2
• Quality of pain (pressure, squeezing, tightness for ACS; sharp, pleuritic for PE or pericarditis). 2, 4
• Temporal features (gradual onset over minutes for ACS; sudden onset for aortic dissection or PE). 2

Associated Symptoms

• Dyspnea, diaphoresis, nausea, syncope, palpitations. 2, 4
• In women and older adults (≥75 years), emphasize atypical presentations: isolated dyspnea, nausea, fatigue, acute delirium, or unexplained falls without classic chest pain. 2

Risk Factors

• Age, sex, diabetes, hypertension, hyperlipidemia, smoking, family history of premature CAD. 2

Focused Physical Examination

Look for specific findings based on suspected etiology: 4

• For ACS: diaphoresis, tachypnea, tachycardia, hypotension, crackles, S3 gallop, new mitral regurgitation murmur. 2, 4
• For aortic dissection: blood pressure differential between arms, new aortic regurgitation murmur. 1
• For PE: tachypnea, tachycardia, hypoxia, unilateral leg swelling. 2

Additional Initial Testing

• Obtain a chest X-ray to evaluate for pneumonia, pneumothorax, widened mediastinum (aortic dissection), heart failure, and pleural effusion. 1, 3
• Consider bedside transthoracic echocardiography in intermediate-risk patients to assess wall motion abnormalities, valvular function, and pericardial effusion. 3

Setting-Specific Management Algorithms

Office/Outpatient Setting

• If ECG is unavailable in the office, immediately refer the patient to the ED so one can be obtained. 1, 4
• If clinical evidence of ACS or life-threatening chest pain is present, transport urgently to the ED by EMS—not by private vehicle. 1, 2, 4
• Never delay transfer for troponin testing in the office setting—delayed transfer should be avoided. 1, 2, 4, 5
• Administer aspirin 162-325 mg (chewed, not swallowed) immediately unless contraindicated (active GI bleeding, known allergy). 2

Emergency Department Setting

• Implement a clinical decision pathway that categorizes patients into low-, intermediate-, and high-risk strata. 3
• Patients with <1% 30-day risk of death or MACE are designated low-risk and can be discharged home without admission or urgent cardiac testing. 3
• Intermediate-risk patients should be managed in an observation unit to shorten length of stay and lower costs. 3
• High-risk features requiring immediate coronary care unit admission include: prolonged ongoing rest pain, hemodynamic instability, elevated troponin above 99th percentile. 2

Immediate Medical Management (When ACS Suspected)

• Aspirin 160-325 mg orally (chewed) as soon as possible unless contraindicated. 2
• Sublingual nitroglycerin unless systolic BP <90 mmHg or heart rate <50 or >100 bpm. 2
• Morphine IV titrated to pain severity for analgesia. 2
• Oxygen only if hypoxic (SpO2 <90%). 2
• Continuous cardiac monitoring for arrhythmias. 2

Critical Pitfalls to Avoid

• Do not rely on nitroglycerin response as diagnostic—esophageal spasm and other conditions may also respond. 2, 4
• Do not assume young age excludes ACS—it can occur even in adolescents without risk factors. 2
• Sharp, pleuritic pain does not exclude ACS—pericarditis and atypical presentations occur. 2
• Women are at risk for underdiagnosis—emphasize accompanying symptoms like nausea, fatigue, and dyspnea. 2
• Compare current ECG with previous ECGs when available, as left ventricular hypertrophy, bundle branch blocks, and ventricular pacing may mask ischemia. 3