What is the proper workup for a 19-year-old pregnant female presenting with intermittent chest pain in the Emergency Room (ER)?

Emergency Department Workup for a 19-Year-Old Pregnant Female with Intermittent Chest Pain

Begin with immediate assessment of vital signs, ECG within 5 minutes, and focused history to identify life-threatening causes—specifically acute coronary syndrome, pulmonary embolism, aortic dissection, and pneumothorax—while recognizing that pregnancy increases risk for these conditions and requires modified diagnostic approaches. 1, 2

Immediate Initial Assessment (First 5-10 Minutes)

Vital Signs and Clinical Stability

• Check blood pressure, heart rate, respiratory rate, and oxygen saturation immediately upon arrival 1
• Assess for hemodynamic instability requiring urgent intervention 1
• Monitor cardiac rhythm continuously 1

12-Lead ECG

• Obtain and interpret ECG within 5 minutes of presentation 1, 2
• Look specifically for ST-segment elevation, ST-segment depression, T-wave inversions, or new Q waves suggesting acute coronary syndrome 1, 2
• Note that negative T waves may appear at increased rates in pregnancy in non-ischemic conditions, so interpret cautiously 1

Focused History

• Characterize chest pain: location (central, retrosternal), quality (pressure, tightness), radiation (shoulders, arms, neck, jaw, back), duration, and exertional relationship 2, 3
• Identify red flag symptoms: severe prolonged pain, syncope, palpitations, shortness of breath, or hemoptysis 2, 3
• Document gestational age (she is likely early pregnancy given age 19) 1
• Assess for DVT symptoms in lower extremities (unilateral leg swelling, pain, warmth) 1

Risk Stratification and Differential Diagnosis

Life-Threatening Causes to Rule Out

• Pulmonary embolism: PE accounts for 20% of maternal deaths in the United States and is a leading cause of pregnancy-related mortality 1
• Acute coronary syndrome: Though rare (3-6 per 100,000 deliveries), pregnancy-related ACS can occur at any gestational stage with 5-10% maternal mortality 1
• Aortic dissection: Consider especially if tearing chest pain radiating to back 2
• Pneumothorax: Look for dyspnea, pain on inspiration, unilateral absent breath sounds 2

Laboratory Testing

Cardiac Biomarkers

• High-sensitivity troponin I is the preferred biomarker for acute myocardial infarction 1, 2
• Elevated troponin should prompt consideration of ischemic heart disease even if pre-eclampsia is present 1
• Serial troponins if initial values borderline or symptoms ongoing 1

D-Dimer Testing

• If clinical suspicion for PE exists, D-dimer can help risk stratify 1
• Negative D-dimer with low-to-intermediate clinical probability can safely exclude PE without imaging 1
• However, D-dimer is less specific in pregnancy and must be interpreted in clinical context 1

Imaging Studies (Radiation-Modified Approach)

Chest X-Ray

• Usually appropriate as initial imaging (Rating 9/9) for pregnant patients with suspected PE 1
• Minimal radiation exposure (RRL ☢) 1
• Can identify alternative diagnoses like pneumothorax, pneumonia, or pulmonary edema 1
• Critical point: Pregnant patients are significantly less likely to undergo chest radiography in practice, which may delay diagnosis—ACOG clearly states radiography should NOT be withheld from pregnant patients 4

Lower Extremity Venous Duplex Ultrasound

• Usually appropriate (Rating 8/9) as initial examination for pregnant patients with suspected PE 1
• No radiation exposure 1
• Positive DVT finding may prevent need for chest imaging with ionizing radiation 1
• If DVT confirmed, treatment is identical to PE, so further PE imaging may be unnecessary 1

CT Pulmonary Angiography (CTPA)

• Usually appropriate (Rating 7/9) if PE remains suspected after initial workup 1
• Should be optimized for pulmonary circulation 1
• Moderate radiation exposure (RRL ☢☢☢) but benefits outweigh risks when PE suspected 1
• Fetal radiation doses from properly performed diagnostic tests present no measurably increased risk of prenatal death, malformation, or mental development impairment 1

Ventilation-Perfusion (V/Q) Scan

• Usually appropriate (Rating 7/9) as alternative to CTPA 1
• May be preferred over CTPA due to lower maternal breast radiation dose 1
• Reduce radiopharmaceutical dose by factor of 2 or more in pregnancy with longer acquisition times 1
• Perform perfusion scan first; if normal, ventilation scan can be avoided 1

Echocardiography

• Transthoracic echocardiography can safely evaluate for wall motion abnormalities, pericardial effusion, aortic dissection, and ventricular function 1
• No radiation exposure 1
• Particularly useful if troponin elevated or ECG abnormal 1

Special Pregnancy Considerations

Avoid or Use with Extreme Caution

• Exercise stress testing: Generally not appropriate in acute setting and contraindicated in pregnancy for chest pain evaluation 1
• Nuclear stress testing (SPECT/PET): Should be avoided due to radiation exposure 1
• Gadolinium-based CMR: Should be discouraged and used only when necessary to guide management 1

Pregnancy-Specific Pathophysiology

• Spontaneous coronary artery dissection more prevalent in pregnancy, especially peripartum 1
• Increased thrombotic risk throughout pregnancy increases PE likelihood 1
• High progesterone levels cause structural changes in vessel walls 1

Clinical Decision Algorithm

1. Immediate triage (0-5 minutes): Vital signs, ECG, IV access, continuous monitoring 1, 2

2. If ECG shows STEMI or high-risk features: Activate cardiac catheterization lab, consider primary PCI (preferred over thrombolysis in pregnancy) 1

3. If hemodynamically unstable: Bedside echocardiography, consider massive PE or acute dissection 1, 2

4. If stable with concerning history:

   • Draw high-sensitivity troponin and D-dimer 1, 2
   • Obtain chest X-ray 1
   • Perform lower extremity venous duplex if any DVT symptoms or high PE suspicion 1

5. If PE suspected and D-dimer positive or high clinical probability:

   • Proceed to CTPA or V/Q scan (discuss risks/benefits with patient) 1
   • Do NOT withhold imaging due to pregnancy if clinically indicated 4

6. If troponin elevated or ECG abnormal:

   • Echocardiography for wall motion abnormalities 1
   • Cardiology consultation 1
   • Consider coronary angiography if ACS confirmed 1

Common Pitfalls to Avoid

• Withholding necessary radiographic studies due to pregnancy: This is the most critical error—delayed diagnosis poses greater risk to mother and fetus than appropriate diagnostic radiation 4
• Attributing symptoms solely to pregnancy: Chest pain in pregnancy requires same serious evaluation as non-pregnant patients 5, 4
• Relying on single normal troponin: Serial troponins needed if symptoms ongoing 1
• Missing accompanying symptoms: Women more likely to present with nausea, shortness of breath alongside chest pain 2
• Discharging with outpatient stress testing: Compliance is suboptimal; complete evaluation in ED when possible 1