Lit Matters #3: Which anticoagulant do providers choose and why?

Acute pulmonary embolism treatment is still shaped as much by habit as by evidence. For most hospitalized PE patients, guidelines favor LMWH or a DOAC over unfractionated heparin, yet clinicians often default to UFH because of perceived reversibility, procedural flexibility, and local culture.

Initial Anticoagulation Choice in PE

• Guideline-concordant first choice: Chest and European PE guidelines favor LMWH and DOACs for initial anticoagulation in most hospitalized patients, not routine UFH-first practice.
• Therapeutic momentum effect: Initial ED anticoagulation often persists across admission because teams are reluctant to switch agents once treatment is started, a handoff dynamic we get into in the episode.
• Quick on off belief: UFH was commonly chosen for its supposed quick on/off profile, but that pharmacology rationale was frequently based on clinician misperception rather than meaningful outcome advantage.
• Procedural flexibility assumption: Many clinicians picked UFH to preserve options for thrombolysis or catheter therapy, even though interviewed interventionalists did not view LMWH as a contraindication to those procedures.
• Institutional culture inertia: Providers were often agnostic about agent choice and instead followed residency habits, local norms, and unwritten service expectations more than formal PE anticoagulation pathways.
• Resource burden tradeoff: LMWH-leaning clinicians highlighted that UFH is labor intensive, with infusion management and repeated aPTT checks shifting workload to nurses and patients without clear added benefit.