What are the appropriate diagnostic steps and treatments for chest pain?

Evaluation and Management of Chest Pain

For any patient presenting with chest pain, immediately obtain a 12-lead ECG within 10 minutes and measure high-sensitivity cardiac troponin to identify or exclude life-threatening causes, particularly acute coronary syndrome, which requires urgent intervention to reduce mortality. 1

Immediate Life-Threatening Conditions to Exclude

The initial assessment must rapidly identify conditions that cause immediate mortality:

• Acute Coronary Syndrome (ACS): Retrosternal pressure, heaviness, or squeezing that builds over minutes, radiates to left arm/jaw/neck, accompanied by diaphoresis, dyspnea, nausea, or syncope 1, 2
• Aortic Dissection: Sudden-onset "ripping" or "tearing" chest pain radiating to back, with pulse differentials between extremities, blood pressure differentials >20 mmHg, or new aortic regurgitation murmur 1, 2
• Pulmonary Embolism: Acute dyspnea with pleuritic chest pain, tachycardia (present in >90%), tachypnea, and associated risk factors 1, 2
• Tension Pneumothorax: Severe dyspnea with unilateral absence of breath sounds 2
• Esophageal Rupture: History of emesis, subcutaneous emphysema, pneumothorax in 20% of patients 1

Essential Diagnostic Steps

History Taking

Obtain focused history including these specific characteristics 1:

• Location and radiation: Pain in chest, shoulders, arms, neck, back, upper abdomen, or jaw all qualify as anginal equivalents 1, 2
• Quality: Pressure, tightness, squeezing, heaviness (suggests cardiac); sharp, stabbing, localized to small area (suggests non-cardiac) 1, 2
• Timing: Gradual onset over minutes suggests ACS; sudden onset suggests dissection or PE; positional changes suggest musculoskeletal or pericarditis 1
• Triggers: Physical exertion or emotional stress suggest angina; occurrence at rest or minimal exertion suggests ACS 1
• Associated symptoms: Diaphoresis, dyspnea, nausea, syncope, palpitations significantly increase likelihood of ACS 2

Critical pitfall: Women, elderly patients, and those with diabetes frequently present with atypical symptoms including isolated dyspnea, nausea, or upper abdominal pain without classic chest pressure 1, 2

Avoid this error: Relief with nitroglycerin is NOT diagnostic of myocardial ischemia, as esophageal spasm and other conditions also respond to nitroglycerin 1, 2, 3

Physical Examination

Perform targeted examination to identify specific syndromes 1:

• ACS: Diaphoresis, tachypnea, tachycardia, hypotension, crackles, S3 gallop, mitral regurgitation murmur (examination may be normal in uncomplicated cases) 1
• Aortic dissection: Pulse differential between extremities (30% of patients), signs of Marfan syndrome or connective tissue disorder 1
• Pericarditis: Fever, friction rub, pain worse supine and improved leaning forward 1, 4
• Pneumothorax: Unilateral absence of breath sounds, dyspnea with inspiration 1
• Costochondritis: Tenderness of costochondral joints reproducible with palpation 1, 2

Immediate Testing

ECG within 10 minutes of presentation is mandatory 1:

• If ECG shows ST-elevation or new ischemic changes: Treat as STEMI per guidelines and arrange immediate transfer by EMS 1
• If initial ECG is nondiagnostic but clinical suspicion remains high: Obtain serial ECGs to detect evolving changes 1
• Consider supplemental leads V7-V9 for suspected posterior MI in intermediate-to-high risk patients with nondiagnostic initial ECG 1

High-sensitivity cardiac troponin is the preferred biomarker standard for establishing diagnosis of acute myocardial infarction 1, 4:

• Measure immediately upon presentation 4
• Serial measurements improve sensitivity for detecting or excluding myocardial injury 1

Chest radiography to evaluate for pneumonia, pleural effusion, pneumothorax, cardiomegaly, or widened mediastinum suggesting dissection 1, 4

Risk Stratification Using Clinical Decision Pathways

Use structured, evidence-based risk assessment tools routinely to categorize patients into low, intermediate, or high-risk strata 1:

• Low-risk patients: Urgent diagnostic testing for suspected CAD is NOT needed 1
• Intermediate-risk or intermediate-to-high pretest probability patients: These patients benefit most from cardiac imaging and further testing 1
• High-risk patients: Require immediate intervention and transfer 1

For pulmonary embolism assessment, use Wells score or Geneva score to determine pretest probability, then obtain D-dimer with age-adjusted cutoffs if low-to-intermediate probability 4, 5

Initial Treatment While Arranging Definitive Care

For suspected ACS 6:

• Aspirin 162-325 mg if no contraindications 5, 6
• Sublingual nitroglycerin 0.4 mg every 5 minutes up to 3 doses (sit patient down to prevent falls from hypotension) 3
• Oxygen only if SpO2 <90% 5
• Establish IV access and initiate crystalloid hydration 5

Contraindications to nitroglycerin 3:

• Concurrent use of phosphodiesterase-5 inhibitors (sildenafil, tadalafil, vardenafil) - causes extreme hypotension
• Use of guanylate cyclase stimulators (riociguat)
• Severe hypotension or volume depletion
• Recent myocardial infarction with hemodynamic instability

Disposition Decisions

Immediate transfer by EMS (not personal automobile) if any of the following 2, 4:

• ECG shows ST-elevation, new ischemic changes, or signs of tamponade 4
• Clinical evidence of ACS with ongoing symptoms 2
• Hemodynamic instability 2
• Suspected aortic dissection or pulmonary embolism 2
• Age >75 years with dyspnea, syncope, acute delirium, or unexplained fall 2

Outpatient management acceptable for 1:

• Low-risk patients with clearly non-cardiac etiology identified
• Stable patients with confirmed musculoskeletal or gastrointestinal causes

Terminology for Documentation

Avoid the term "atypical chest pain" as it is misleading and can be misinterpreted as benign 1, 7

Use these specific descriptors instead 1:

• "Cardiac" if ischemic heart disease is suspected
• "Possibly cardiac" if uncertain
• "Noncardiac" if heart disease is not suspected

Shared Decision-Making

For clinically stable patients, include them in decision-making by discussing 1:

• Risk of adverse events
• Radiation exposure from imaging
• Costs of testing
• Alternative diagnostic options

This approach balances thoroughness with cost-value considerations while maintaining focus on mortality reduction 1.