What is the initial workup and treatment for a patient presenting with chest pain?

Initial Workup and Treatment for Chest Pain

Obtain a 12-lead ECG within 10 minutes of patient arrival and measure cardiac troponin immediately—these are the two essential diagnostic tests that determine whether the patient has acute coronary syndrome and guide all subsequent management decisions. 1, 2

Immediate Assessment and Triage

Critical First Steps

• Place the patient on continuous cardiac monitoring immediately with emergency resuscitation equipment and a defibrillator readily available 2
• Obtain and interpret a 12-lead ECG within 10 minutes to identify ST-segment elevation myocardial infarction (STEMI), ST depression, new left bundle branch block, Q waves, or new T-wave inversions 1, 2
• Measure cardiac troponin as soon as possible after presentation, as this is the most sensitive test for diagnosing acute myocardial injury 1, 2
• Monitor vital signs and cardiac rhythm continuously for all patients with suspected acute coronary syndrome 2

Transport Considerations

• If evaluating the patient in an office setting and ACS is suspected, immediately transfer by emergency medical services (EMS) rather than private vehicle 1, 2
• EMS transport provides critical advantages: prehospital ECG acquisition, trained personnel who can treat arrhythmias and implement defibrillation en route, and shorter travel time to the emergency department 1
• If an ECG cannot be obtained in the office setting within 10 minutes, initiate immediate transfer to the emergency department 1

Focused History and Physical Examination

Key Historical Elements to Obtain

• Pain characteristics: exact location, radiation pattern, quality (sharp, pressure, burning), severity, onset (sudden vs. gradual), and duration 1, 3, 2
• Temporal features: relationship to exertion, meals, or breathing; aggravating and relieving factors 1, 3, 2
• Associated symptoms: dyspnea, diaphoresis, nausea, vomiting, syncope, palpitations, fever, or anxiety 1, 3, 2
• Cardiovascular risk factors: diabetes, hypertension, hyperlipidemia, smoking, family history of premature coronary disease 2
• Past medical history: known cardiac conditions, previous myocardial infarction, prior revascularization 3

High-Risk Features Requiring Immediate Attention

• Interruption of normal activity with accompanying cold sweat, nausea, vomiting, fainting, or severe anxiety 1, 2
• Recurrent ischemia, hemodynamic instability, major arrhythmias, or diabetes mellitus 2

Important Clinical Caveat

Physical examination contributes minimally to diagnosing myocardial infarction unless shock is present 2. There is frequently a lack of correlation between symptom intensity and disease seriousness 2. Women, elderly patients, and those with diabetes may present with atypical symptoms such as isolated dyspnea, nausea, lightheadedness, or vague abdominal symptoms rather than classic chest pain 2.

ECG Interpretation and Serial Monitoring

Initial ECG Findings and Management

• If STEMI or new left bundle branch block is present, treat according to STEMI guidelines with consideration for immediate reperfusion therapy 1, 2
• If ST depression or new T-wave inversions are present, treat according to NSTE-ACS guidelines 1, 2
• If diffuse ST elevation is present, consider acute pericarditis rather than STEMI 1

When Initial ECG is Nondiagnostic

• Perform serial ECGs to detect potential ischemic changes, especially when clinical suspicion remains high, symptoms persist, or the clinical condition deteriorates 1, 2
• Consider supplemental leads V7-V9 to rule out posterior myocardial infarction in patients with intermediate-to-high clinical suspicion and nondiagnostic initial ECG 1
• Compare the ECG with previous tracings if available 1
• A normal or unchanged ECG does not exclude ACS—decision-making should never be based solely on a single normal ECG 1, 2

Initial Pharmacologic Treatment

For Suspected Acute Coronary Syndrome

• Administer aspirin 250-500 mg (chewable or water-soluble) as soon as possible 1, 2
• Consider short-acting nitrates if there is no bradycardia or hypotension 1
• Relief with nitroglycerin should NOT be used as a diagnostic criterion for myocardial ischemia, as other conditions may show comparable response 2

Critical Contraindication

• Withhold antithrombotic therapy if aortic dissection is suspected (ADD score ≥1) 1

Additional Diagnostic Testing

Cardiac Troponin Measurement

• Cardiac troponin is the most sensitive test for diagnosing acute myocardial injury and must be measured in conjunction with clinical data (history, examination, ECG) to implement appropriate therapy 1
• In the primary care setting, troponin testing should rarely be requested—instead, refer the patient to the hospital for definitive evaluation 4
• Delayed transfer to determine troponin in the office setting can be detrimental and should be avoided 1

Chest Radiography

• Obtain chest radiography to evaluate for other potential cardiac, pulmonary, or thoracic causes of chest pain, including pneumonia, pneumothorax, pulmonary embolism, or aortic dissection 2

Differential Diagnosis Considerations

Life-Threatening Causes Beyond ACS

• Acute aortic dissection: sudden severe tearing pain, often radiating to the back; transfer patients with high probability (ADD score ≥1) to centers with 24/7 aortic imaging and cardiac surgery 1
• Pulmonary embolism: sudden dyspnea with pleuritic chest pain; use clinical prediction scores to determine likelihood; transfer unstable patients to centers equipped for thrombectomy 1
• Tension pneumothorax: sudden-onset sharp chest pain with dyspnea 3, 5
• Cardiac tamponade: signs of cardiogenic shock, jugular venous distension, respiratory distress; requires rapid transfer to centers with pericardiocentesis capability 1

Common Non-Cardiac Causes

• Musculoskeletal/costochondritis: reproducible chest wall tenderness, pain with movement 3, 6
• Gastroesophageal reflux disease: burning retrosternal pain related to meals 3, 6
• Anxiety/panic disorder: consider in patients with low suspicion for ACS 6
• Acute pericarditis: diffuse ST elevation on ECG, pleuritic chest pain 1
• Pneumonia: chest pain associated with respiratory infection, fever 5

Disposition and Follow-Up

Patients Requiring Immediate Hospital Transfer

• All patients with ECG changes consistent with ACS (STEMI or NSTE-ACS) 1, 2
• Patients with high-risk features: recurrent ischemia, elevated troponin, hemodynamic instability, major arrhythmias 2
• Patients with suspected life-threatening conditions: aortic dissection, pulmonary embolism with instability, cardiac tamponade 1

Patients Suitable for Outpatient Evaluation

• Stable patients with low suspicion for ACS and normal/nondiagnostic initial ECG can undergo outpatient stress testing, coronary CT angiography, or cardiac MRI 2, 6
• Consider the Marburg Heart Score or INTERCHEST clinical decision rule to estimate ACS risk in the outpatient setting 6

Common Pitfall to Avoid

Patients often delay seeking medical attention for chest pain, with longer delays in older patients and those in rural areas 2. Do not contribute to further delay by attempting extensive diagnostic workup in the office setting—when ACS is suspected, immediate transfer to the emergency department is the priority 1, 2.