What follow-up blood work is recommended for an adult patient with a history of pulmonary embolism?

Follow-up Blood Work for Patients with History of Pulmonary Embolism

Routine laboratory monitoring is not recommended for patients with a history of pulmonary embolism who have completed their acute treatment phase. The focus of follow-up should be clinical evaluation rather than routine blood work. 1

Clinical Follow-up Timeline

All patients require a mandatory clinical evaluation at 3-6 months after the acute PE episode, regardless of symptoms, to assess for:

• Signs of VTE recurrence 1
• Bleeding complications from anticoagulation 1
• Persistent or new-onset dyspnea or functional limitation 1
• Occult malignancy 1

After this initial evaluation, yearly follow-up examinations are recommended to monitor for late complications. 1

Specific Blood Work Considerations

Baseline Platelet Count Only

• A single baseline platelet count is recommended at initiation of heparin therapy, but routine serial platelet monitoring during anticoagulation is not beneficial and should not be performed. 1
• This applies to patients receiving heparin products; no ongoing platelet monitoring is needed. 1

Biomarkers for Risk Stratification (When Symptomatic)

If patients present with persistent or new-onset dyspnea at follow-up, consider:

• NT-proBNP or BNP levels to assess for possible chronic thromboembolic pulmonary hypertension (CTEPH) 1, 2
• Elevated natriuretic peptides suggest the need for further diagnostic workup including V/Q scanning and possible referral to a PH/CTEPH expert center 1

D-dimer Testing

• D-dimer testing is NOT recommended for routine follow-up after PE 1
• D-dimer has no established role in monitoring patients with prior PE who are asymptomatic 1

Anticoagulation Monitoring

The monitoring requirements depend on the anticoagulant used:

• For NOACs (apixaban, rivaroxaban, edoxaban, dabigatran): No routine laboratory monitoring is required 1, 3
• For warfarin/VKA: Regular INR monitoring through anticoagulation clinic or primary care is required 1

Key Decision Point at 3-6 Months

At the 3-6 month evaluation, the critical decision is whether to continue anticoagulation, not what blood work to order. 1 This decision is based on:

• Provoked PE with transient risk factor: Discontinue anticoagulation after 3 months 1, 3
• Unprovoked PE or persistent risk factors: Consider indefinite anticoagulation, weighing bleeding risk versus recurrence risk 1, 3, 4
• Cancer-associated PE: Continue indefinite anticoagulation with LMWH or NOAC 1, 3

Important Caveats

The most critical "blood work" is actually clinical assessment, not laboratory tests. 1 Patients should not be lost to follow-up, as there is a lifelong risk of VTE recurrence after a first PE episode. 1

Malignancy screening should be tailored based on clinical assessment rather than routine extensive screening with blood work. 1 Standard age-appropriate cancer screening (cervical, prostate, breast) is recommended, but routine tumor markers or extensive screening beyond this is not supported by evidence. 1

For patients on anticoagulation beyond 6 months, no additional routine blood work is needed beyond what is required for the specific anticoagulant being used (INR for warfarin only). 1