What are the recommended treatments and when to seek medical attention for left arm pain?

Left Arm Pain: When to Seek Emergency Care and Treatment Approach

If you experience left arm pain accompanied by chest discomfort, shortness of breath, nausea, or diaphoresis, call 9-1-1 immediately—this may represent an acute coronary syndrome requiring urgent evaluation. 1

Immediate Emergency Evaluation Required

Left arm pain demands urgent medical attention when accompanied by:

• Chest discomfort lasting >5 minutes that is crushing, pressure-like, or burning in quality, particularly if substernal or left precordial 1
• Radiation pattern: Pain extending from chest to left arm, neck, or jaw suggests high likelihood of acute myocardial infarction 1
• Associated symptoms: Shortness of breath, nausea/vomiting, diaphoresis, lightheadedness, or syncope 1
• Duration >20 minutes without relief from rest or nitroglycerin 1, 2
• New onset in patients with known coronary artery disease or cardiovascular risk factors 1

Critical Action Steps

Call 9-1-1 immediately rather than self-transporting or waiting—do not delay for multiple nitroglycerin doses. 1 The traditional recommendation to take 3 nitroglycerin doses before calling has been abandoned because self-medication causes dangerous delays in patients with acute coronary syndromes. 1

High-Risk Clinical Features

Left arm pain carries particularly high risk when the patient presents with:

• Male sex, age >40 years (>35 for men, >40 for women) 1
• Known history of coronary artery disease or prior myocardial infarction 1
• Diabetes mellitus 1
• Pain described as reproducing prior documented angina 1
• Transient hypotension, diaphoresis, pulmonary edema, or new mitral regurgitation murmur on examination 1

Research demonstrates that substernal or left chest pain radiating to the left arm has >90% likelihood of excluding right coronary artery disease, indicating significant left-sided coronary involvement. 3

Lower-Risk Presentations

Left arm pain is less likely cardiac when:

• Sharp, fleeting, positional, or related to inspiration 4
• Reproducible by palpation suggesting musculoskeletal origin 4
• Point tenderness over chest wall indicating costochondritis 4
• Isolated to arm without chest symptoms 5
• Associated with repetitive occupational activities suggesting regional musculoskeletal syndrome 5

However, up to 30% of STEMI patients present with atypical symptoms, particularly women, elderly patients, and those with diabetes—so maintain high suspicion even without classic presentation. 1

Emergency Department Evaluation

When presenting with left arm pain concerning for cardiac origin:

• 12-lead ECG must be obtained within 10 minutes of arrival to detect ST-segment elevation or depression 1, 4
• Cardiac biomarkers (high-sensitivity troponin) should be measured, with values above 99th percentile indicating myocardial injury 1
• Continuous cardiac monitoring to detect life-threatening arrhythmias 1
• Chest radiography to evaluate for alternative diagnoses including aortic dissection (look for mediastinal widening) 4, 6
• Bilateral arm blood pressure measurement—difference >20 mmHg suggests aortic dissection 6

Non-Cardiac Causes Requiring Consideration

Musculoskeletal Pain

• Costochondritis or chest wall syndrome: Pain reproducible by palpation, point tenderness 4
• Regional pain syndrome: Associated with repetitive work activities, forearm involvement 5

Neurological Pain

• Cervical radiculopathy: Pain radiating from neck down arm, may mimic cardiac pain 7
• Neuropathic pain: Burning or electric quality, may require gabapentin or pregabalin 1

Gastrointestinal Mimics

• Gastroesophageal reflux: Can produce squeezing sensations radiating to arm, improves with antacids 4

Treatment Approach Based on Diagnosis

For Confirmed Acute Coronary Syndrome

• Immediate aspirin 162-325 mg (chewed for faster absorption) unless contraindicated 1
• Dual antiplatelet therapy with P2Y12 inhibitor 1
• Anticoagulation (heparin or enoxaparin) 1
• Primary percutaneous coronary intervention is preferred reperfusion strategy when available within 120 minutes 1

For Musculoskeletal Pain

• NSAIDs for anti-inflammatory effect 5
• Physical therapy and ergonomic workplace modifications 5
• Avoidance of repetitive activities that precipitate symptoms 5

For Neuropathic Pain

• First-line agents: Gabapentin, pregabalin, or tricyclic antidepressants (nortriptyline, desipramine) 1
• Adequate trial requires 6-8 weeks including 2 weeks at maximum tolerated dose 1
• Combination therapy if monotherapy provides <30% pain reduction 1

Critical Pitfalls to Avoid

• Do not dismiss left arm pain in women, elderly, or diabetic patients who may present atypically without chest pain 1
• Do not rely on nitroglycerin response as diagnostic—esophageal spasm also responds to nitroglycerin 1
• Do not delay calling 9-1-1 for self-medication attempts with antacids or multiple nitroglycerin doses 1
• Do not assume normal initial ECG excludes acute coronary syndrome—serial ECGs and troponins are required 1
• Do not use term "atypical chest pain" as this minimizes symptoms; instead characterize as cardiac, possibly cardiac, or noncardiac 1, 4

Women are at particular risk for underdiagnosis and delayed treatment—maintain high suspicion even when accompanying symptoms (nausea, fatigue, dyspnea) predominate over chest discomfort. 1