What is the approach to reviewing and managing a patient with chest pain radiating to the left arm?

Approach to Chest Pain Radiating to Left Arm: Review and Management

Patients with chest pain radiating to the left arm should be immediately evaluated for acute coronary syndrome (ACS), with prompt referral to an emergency department or specialized chest pain unit for definitive diagnosis and management. 1

Initial Assessment

High-Risk Features

• History findings suggestive of ACS:

  • Chest or left arm pain/discomfort as chief symptom
  • Pain reproducing prior documented angina
  • Known history of coronary artery disease (CAD) or previous MI 2
  • Pain lasting >20 minutes 2
  • Radiation to left arm, neck, jaw, or back 1

• Physical exam findings:

  • Transient mitral regurgitation murmur
  • Hypotension
  • Diaphoresis
  • Pulmonary edema or rales 2

• Associated symptoms:

  • Diaphoresis
  • Nausea/vomiting
  • Dyspnea
  • Lightheadedness
  • Syncope 1

Immediate Actions

1. Call 9-1-1 immediately for emergency medical services transport 2
2. Aspirin administration: 162-325mg chewed while awaiting EMS 2
3. Nitroglycerin use: If previously prescribed, take 1 sublingual dose. If symptoms are unimproved or worsening after 5 minutes, call 9-1-1 immediately 2
   • May repeat nitroglycerin every 5 minutes up to 3 doses while awaiting ambulance 2
   • Caution: Avoid excessive use which may lead to tolerance 3
   • Patients should sit when taking nitroglycerin to prevent falls from lightheadedness 3

Emergency Department Evaluation

Diagnostic Testing

1. 12-lead ECG: Perform within 10 minutes of arrival 1

   • Look for ST-segment elevation/depression, T-wave inversion
   • Consider additional leads (V7-V9) if posterior MI suspected

2. Cardiac biomarkers:

   • Troponin testing at 0,3, and 6 hours
   • Do not delay treatment if clinical suspicion is high 1

3. Additional testing:

   • Chest radiography to exclude other causes
   • Transthoracic echocardiography to evaluate wall motion abnormalities
   • Consider coronary CT angiography for low-to-intermediate risk patients 1, 4

Risk Stratification

• High likelihood of ACS: 2

  • New/transient ST-segment deviation ≥1mm
  • T-wave inversion in multiple precordial leads
  • Elevated cardiac troponins

• Intermediate likelihood of ACS:

  • Age >70 years
  • Male sex
  • Diabetes mellitus
  • Extracardiac vascular disease
  • ST depression 0.5-1mm or T-wave inversion >1mm

• Low likelihood of ACS:

  • Chest discomfort reproduced by palpation
  • T-wave flattening or minor inversion
  • Normal ECG
  • Normal cardiac markers

Management Based on Risk Stratification

High-Risk Patients (STEMI)

• Immediate reperfusion therapy (primary PCI preferred)
• If PCI not available within 120 minutes, consider fibrinolysis 1

High-Risk Patients (NSTE-ACS)

• Antiplatelet therapy (aspirin + P2Y12 inhibitor)
• Anticoagulation with heparin
• Early invasive strategy (coronary angiography within 24 hours) 1

Low-to-Intermediate Risk Patients

• Consider non-invasive testing (stress test, coronary CT)
• For patients with negative workup and no evidence of myocardial ischemia, discharge may be considered 5
• Studies show that low-risk patients without evidence of MI can be safely discharged with appropriate follow-up, with cardiovascular mortality of only 0.1% at 4 weeks 5

Special Considerations

Atypical Presentations

• Women, elderly, and diabetic patients may present with atypical symptoms:
  • Unusual fatigue
  • Shortness of breath
  • Indigestion
  • Anxiety
  • Generalized weakness 1

Posterior MI

• May present with interscapular pain
• ECG may show ST depression in leads V1-V3 rather than classic ST elevation
• Additional posterior leads (V7-V9) may be required 1

Non-Cardiac Causes

• For recurrent chest pain with negative cardiac workup, consider:
  • Gastroesophageal disorders
  • Musculoskeletal pain
  • Anxiety/panic disorder 2
  • Referral to cognitive-behavioral therapy is reasonable for patients with recurrent presentations and negative workups 2

Pitfalls to Avoid

1. Delayed activation of emergency services - Patients often delay seeking care due to self-medication or symptom re-evaluation 2
2. Underestimating atypical presentations - Women, elderly, and diabetic patients may present with non-classic symptoms 1
3. Missing posterior MI - Consider posterior leads (V7-V9) when standard ECG is non-diagnostic 1
4. Premature discharge - Even with normal initial troponin, serial measurements are essential 1
5. Failure to recognize anxiety-related chest pain - For recurrent presentations with negative workups, psychological factors should be considered 2