Contributor: Aaron Lessen, MD

Educational Pearls:

Patients with pulmonary embolism (PE) are divided into three risk categories
- Low risk (non-massive PE): patients are stable
  - Treatment: prescribe anticoagulants and discharge home
- Intermediate risk (submassive PE): patients are stable but display evidence of clot burden such as elevated troponin, elevated BNP, and/or right heart strain
  - Treatment is controversial
- High risk (massive PE): patients are unstable with hypotension, hypoxia, and/or respiratory distress
  - Treatment: IV thrombolysis to prevent decompensation
A recent randomized controlled trial evaluated treatment of intermediate risk PE patients
- Patients were randomized to receive either thrombectomy with anticoagulation or anticoagulation alone
- The primary outcome evaluated changes in right ventricular enlargement at 48 hours
  - A controversial primary outcome because it does not speak to mortality or incidence of other necessary aggressive interventions
  - Low clinical significance
- The study found that thrombectomy significantly reduced right ventricular enlargement faster than anticoagulation alone. However, there was no statistical difference in mortality or need for other treatments
Treatment for intermediate risk PE patient remains controversial
The same study will have second follow-up at 90 days to see if there are other benefits

References

Lookstein RA, Konstantinides SV, Weinberg I, Dohad SY, Rosol Z, Kopeć G, Moriarty JM, Parikh SA, Holden A, Channick RN, McDonald B, Nagarsheth KH, Yamada K, Rosovsky RP; STORM-PE Trial Investigators. Randomized Controlled Trial of Mechanical Thrombectomy With Anticoagulation Versus Anticoagulation Alone for Acute Intermediate-High Risk Pulmonary Embolism: Primary Outcomes From the STORM-PE Trial. Circulation. 2026 Jan 6;153(1):21-34. doi: 10.1161/CIRCULATIONAHA.125.077232. Epub 2025 Nov 3. PMID: 41183181.

Summarized by Meg Joyce, MS2 | Edited by Meg Joyce & Jorge Chalit, OMS4

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Podcast 1001: Acute Intermediate Risk Pulmonary Embolism

Emergency Medical Minute