Can a pregnant patient with potential pulmonary embolism (PE) symptoms that resolved be sent home without evaluation if currently asymptomatic?

Management of Suspected Pulmonary Embolism in Pregnant Patients with Resolved Symptoms

A pregnant patient with suspected PE symptoms that have resolved should NOT be sent home without evaluation, even if currently asymptomatic, as PE is a leading cause of maternal mortality and requires immediate diagnostic workup.

Rationale for Immediate Evaluation

Pulmonary embolism (PE) is a leading cause of pregnancy-related mortality in the developed world, accounting for 20% of maternal deaths in the United States 1. The European Society of Cardiology (ESC) strongly recommends instituting anticoagulation therapy as soon as possible while the diagnostic workup is ongoing, unless the patient has active bleeding or absolute contraindications 2.

Diagnostic Approach for Pregnant Patients with Suspected PE

Step 1: Clinical Assessment and D-dimer Testing

• Use validated clinical prediction tools:
  • The modified Wells score with a cutoff of ≥6 points is considered most appropriate for evaluating suspected PE in pregnancy 2
  • The pregnancy-adapted YEARS algorithm combined with D-dimer levels can safely exclude PE in pregnancy 2

Step 2: Initial Imaging

• Chest radiography (CXR) should be performed as the first radiation-associated procedure 1
• If CXR is normal, proceed with lung scintigraphy (V/Q scan) as the preferred test 1
• If CXR is abnormal, proceed with CTPA 2

Step 3: Further Imaging Based on Initial Results

• For V/Q scan:
  • Normal perfusion scan effectively rules out PE
  • If V/Q scan is nondiagnostic, proceed to CTPA 1
• CTPA is highly sensitive and specific with fewer "nondiagnostic" studies than V/Q scans 1

Considerations for Imaging in Pregnancy

Radiation Exposure Comparison

Modality	Maternal Breast Radiation	Lung Tissue Radiation
V/Q scan	0.98-1.07 mGy	5.7-13.5 mGy
CTPA	10-60 mGy	39.5 mGy

• The American Thoracic Society/Society of Thoracic Radiology recommends scintigraphy over CTPA mainly due to maternal radiation dose concerns 1
• When lung scans are indicated in pregnant women, the administered dose of radiopharmaceuticals should be reduced by a factor of 2 or more, with correspondingly longer acquisition times 1

Management Approach

Immediate Management

• Anticoagulation should be initiated while awaiting diagnostic confirmation unless contraindicated 1, 2
• Low molecular weight heparin (LMWH) is the preferred agent in pregnancy 2
• Continue anticoagulation until PE is definitively ruled out 2

Treatment if PE Confirmed

• Administer therapeutic, fixed doses of LMWH based on early pregnancy weight 1
• Do not use NOACs (non-vitamin K antagonist oral anticoagulants) during pregnancy or lactation 1
• For high-risk PE, especially peri-partum, unfractionated heparin (UFH) is typically used 2

Important Caveats

• Symptoms that have resolved may return and potentially worsen
• PE can present with nonspecific symptoms that fluctuate in intensity
• The postpartum period is a particularly vulnerable time with risks of cardio-respiratory decompensation 2
• Temporary symptom resolution does not exclude the presence of PE

Follow-up Considerations

• Maintain close monitoring for women with suspected or confirmed PE
• Educate patients on signs and symptoms of PE, including pleuritic chest pain, cough, and sweating 2
• A multidisciplinary approach involving maternal-fetal medicine specialists, cardiologists, and emergency physicians is recommended for complex cases 2

The high mortality risk associated with untreated PE in pregnancy, combined with the availability of safe diagnostic algorithms, makes immediate evaluation essential even when symptoms have temporarily resolved.