What is the recommended evaluation and initial management for an adult patient presenting to a primary‑care clinic with chest pain, including assessment for life‑threatening cardiac causes, risk‑factor assessment, electrocardiogram, risk stratification, and appropriate treatment and disposition?

Chest Pain Evaluation in Primary Care: Immediate Assessment and Management

First 10 Minutes: Life-Threatening Exclusion Protocol

Obtain a 12-lead ECG within 10 minutes of patient arrival and draw high-sensitivity cardiac troponin immediately—these two tests are mandatory for every adult with acute chest pain, regardless of presentation. 1, 2

• Measure vital signs including heart rate, bilateral arm blood pressures (to detect >20 mmHg differential suggesting aortic dissection), respiratory rate, and oxygen saturation 1, 3
• Perform focused cardiovascular exam for diaphoresis, tachypnea, pulmonary crackles, S3 gallop, new murmurs, pericardial friction rub, unilateral absent breath sounds, pulse differentials, and jugular venous distension 1, 3

Six Immediately Fatal Conditions to Exclude

1. Acute Coronary Syndrome (ACS): Retrosternal pressure/squeezing building over minutes, radiating to left arm/jaw/neck, with diaphoresis, dyspnea, or nausea 1, 3
2. Aortic Dissection: Sudden "ripping/tearing" pain radiating to back, pulse differential in ~30% of cases, systolic BP difference >20 mmHg between arms 1, 3
3. Pulmonary Embolism: Sudden dyspnea with pleuritic chest pain; tachycardia present in >90% of patients 1, 3
4. Tension Pneumothorax: Dyspnea, unilateral absent breath sounds, tracheal deviation, hypotension 1, 3
5. Cardiac Tamponade: Pleuritic pain worse supine, jugular venous distension, hemodynamic compromise 1, 3
6. Esophageal Rupture: Severe pain after forceful vomiting, subcutaneous emphysema 1, 3

Critical History Elements (Obtain While Awaiting ECG/Troponin)

Pain Characteristics That Increase ACS Likelihood

• Quality: Pressure, squeezing, gripping, heaviness, tightness, or constriction (patients rarely use the word "pain" itself) 1
• Onset: Gradual build over several minutes, not instantaneous 1
• Location & Radiation: Retrosternal with radiation to left arm, neck, jaw, or between shoulder blades 1, 3
• Duration: Several minutes (fleeting seconds argues against ischemia) 1
• Precipitants: Physical exertion or emotional stress 1
• Associated symptoms: Dyspnea, diaphoresis, nausea/vomiting, lightheadedness, presyncope, or syncope markedly raise ACS probability 1, 3

Features Suggesting Alternative Diagnoses

• Sharp, stabbing, fleeting pain localized to very small area or radiating below umbilicus = low probability ischemia 1
• Pain worsening with inspiration and lying supine suggests pericarditis (though 13% of pleuritic pain patients still have ACS) 1, 3
• Pain reproducible with chest wall palpation suggests costochondritis (accounts for 43% of non-cardiac chest pain in primary care) 1, 3

Cardiovascular Risk Factor Documentation

• Age, sex, diabetes mellitus, hypertension, hyperlipidemia, smoking, family history of premature CAD 1
• Post-menopausal status in women 4
• Diabetes is particularly high-risk for both macrovascular disease and atypical presentations 4, 1

Special Population Considerations

Women (High Risk for Underdiagnosis)

• Women present with ACS in 87-92% of cases but are frequently underdiagnosed 1
• Emphasize accompanying symptoms: jaw/neck pain (10% vs 4% in men), nausea/vomiting (32% vs 23%), epigastric discomfort, palpitations, inter-scapular pain (61.9% vs 54.8%), dyspnea, fatigue 1
• Use sex-specific high-sensitivity troponin thresholds (>16 ng/L for women vs >34 ng/L for men)—this reclassifies ~30% of women with STEMI who would be missed with universal cutoff 1

Older Adults (≥75 Years)

• May present with isolated dyspnea, syncope, acute delirium, or unexplained falls without classic chest pain 1, 2
• Age >75 years with accompanying symptoms is a high-risk feature requiring immediate action 1

Patients with Diabetes

• More likely to present with vague abdominal symptoms, confusion, or isolated dyspnea 1
• Higher risk for silent ischemia 1

ECG Interpretation & Serial Monitoring

• Interpret for STEMI (≥1 mm ST-elevation in contiguous leads), ST-depression, T-wave inversions, or pericarditis patterns (diffuse ST-elevation with PR-depression) 1, 2
• 30-40% of acute MIs present with normal or nondiagnostic initial ECG—a normal ECG does NOT exclude ACS 1, 2
• If initial ECG nondiagnostic but suspicion remains high: obtain serial ECGs every 15-30 minutes 1, 2
• Consider posterior leads V7-V9 when intermediate-to-high suspicion exists with nondiagnostic standard ECG 1, 2

Troponin Testing Strategy

• High-sensitivity troponin is the most sensitive and specific biomarker for myocardial injury 1, 2
• A single normal troponin does NOT exclude ACS—repeat at 1-3 hours (high-sensitivity) or 3-6 hours (conventional assay) 1, 2
• Single-sample rule-out acceptable only if: symptom onset ≥3 hours before presentation, normal ECG, and hs-troponin below limit of detection 1

Immediate Management Based on Initial Results

If STEMI or New Ischemic ECG Changes Present

Activate emergency medical services immediately—do NOT transport by personal automobile—and arrange urgent transfer to facility with 24/7 cardiac catheterization capability. 1, 2

• Target door-to-balloon time <90 minutes (primary PCI preferred) or door-to-needle <30 minutes (fibrinolysis) 1
• While awaiting EMS: give chewed aspirin 162-325 mg (unless contraindicated), sublingual nitroglycerin (unless SBP <90 mmHg or HR <50 or >100 bpm), IV morphine 4-8 mg for pain 1

If Initial ECG and Troponin Normal

• Do NOT discharge after single troponin if drawn <6 hours from symptom onset 1
• Repeat troponin at 3-6 hours after symptom onset 1, 2
• Continue serial ECGs if symptoms persist 1, 2

Low-Risk Criteria (After Serial Testing)

Patients can be classified low-risk when ALL of the following are present:

• Normal/nondiagnostic ECG 1, 2
• Negative troponin at presentation AND at 6-12 hours 1, 2
• Stable vital signs 1, 2
• No ongoing chest pain 1, 2
• No heart failure signs 1, 2

Low-risk patients may be observed in chest-pain unit for 10-12 hours OR discharged for outpatient stress testing within 72 hours. 1, 2

High-Risk Features Requiring Immediate CCU Admission

• Prolonged ongoing rest pain >20 minutes 1, 2
• Hemodynamic instability (SBP <100 mmHg, HR >100 or <50 bpm) 1, 2
• Troponin above 99th percentile 1, 2
• Evidence of left ventricular failure (crackles, S3 gallop, new murmurs) 1, 2

Critical Pitfalls to Avoid

• Do NOT rely on nitroglycerin response to differentiate cardiac from non-cardiac pain—esophageal spasm and other conditions also respond 1, 3
• Do NOT delay EMS transport for troponin testing in office settings when ACS is suspected 1, 5, 6
• Do NOT assume young age excludes ACS—it can occur in adolescents without risk factors 1
• Do NOT dismiss chest pain in women, elderly, or diabetics based on atypical presentations 1, 3
• Do NOT use the term "atypical chest pain"—describe as "cardiac," "possibly cardiac," or "non-cardiac" to prevent misinterpretation as benign 1
• Do NOT assume normal physical exam excludes ACS—uncomplicated MI can present with completely normal findings 1, 3
• Do NOT assume reproducible chest wall tenderness rules out ACS—up to 7% of such patients still have ACS 1

Office-Based Management Algorithm

If ECG Unavailable in Office

Refer patient immediately to emergency department for ECG acquisition—do not delay. 1

If Clinical Evidence of ACS or Life-Threatening Cause Exists

Arrange urgent EMS transport immediately—do NOT postpone transfer for additional testing. 1, 5, 6

If Low Suspicion After Initial Evaluation

• Consider alternative diagnoses: costochondritis (43% of non-cardiac chest pain), GERD (10-20% of presentations), pericarditis, anxiety/panic disorder 1, 3
• Chest radiography when pulmonary etiologies suspected 3
• Empiric PPI trial for suspected GERD 3

Risk Stratification Tools

• Apply validated clinical decision pathways (TIMI, GRACE scores) for chest pain evaluation 1, 2
• Marburg Heart Score and INTERCHEST clinical decision rule can estimate ACS risk in primary care 6

Key Takeaway for Primary Care

In primary care, an ECG is the only investigation required for most patients while referral is made to hospital. Troponin testing should rarely be requested in the primary care setting for suspected ACS—immediate transfer for definitive risk stratification is required instead. 5, 6