How should the Modified Rankin Scale be used to assess functional status in a pregnant woman with cerebral venous thrombosis at diagnosis, at discharge after therapeutic low‑molecular‑weight heparin, and at 3‑month and 6‑month postpartum follow‑up?

Modified Rankin Scale Assessment in Pregnancy-Related Cerebral Venous Thrombosis

The Modified Rankin Scale (mRS) should be systematically assessed at diagnosis, hospital discharge, and at 3-month and 6-month postpartum follow-up to track functional recovery and identify patients at risk for poor outcomes (mRS >2), which is associated with encephalopathy, anemia, and puerperal infection in this population. 1

Timing and Purpose of mRS Assessment

At Diagnosis (Baseline)

• Document baseline functional status using mRS to establish a reference point for measuring treatment response and recovery trajectory. 1
• This initial assessment helps stratify risk, as patients presenting with encephalopathy have a 12.8-fold increased odds of poor outcome (mRS >2) at 30 days. 1
• Identify high-risk features at presentation including fever/puerperal infection (OR 2.7 for poor outcome) and anemia (OR 2.2 for poor outcome). 1

At Hospital Discharge (After LMWH Treatment)

• Assess mRS at discharge to determine immediate treatment response, as approximately 50% of pregnancy-related CVT patients may be dead or disabled at this timepoint without appropriate anticoagulation. 2
• The primary outcome measure should be functional independence, defined as mRS ≤2. 3
• Patients with focal motor deficits (OR 2.93) and hemorrhagic infarctions (OR 2.81) at presentation are independent predictors of unfavorable discharge outcomes. 2

At 3-Month Postpartum Follow-Up

• Evaluate mRS at 3 months as this represents a critical timepoint for assessing intermediate recovery, particularly since most guidelines recommend 3-12 months of anticoagulation for CVT. 4, 5
• This assessment helps determine whether to continue or modify anticoagulation therapy based on functional recovery and recanalization status. 5

At 6-Month Postpartum Follow-Up

• The 6-month mRS assessment is the standard endpoint for determining long-term functional outcome in CVT, with complete recovery defined as mRS 0-1 and functional independence as mRS ≤2. 3
• Hemorrhagic infarction at baseline is the most significant predictor of long-term unfavorable outcome (OR 5.87). 2
• This timepoint guides decisions about duration of anticoagulation and risk of recurrence. 4

Clinical Application Algorithm

Risk Stratification Based on mRS Trajectory

• Patients with persistent mRS >2 at discharge require closer follow-up and extended anticoagulation, as they have higher risk of long-term disability. 1, 2
• Monitor for reversible factors: anemia and puerperal infection are modifiable predictors that clinicians should aggressively treat to prevent poor outcomes. 1
• Encephalopathy at presentation carries the highest mortality risk (OR 7.7), warranting intensive monitoring even if initial mRS appears favorable. 1

Treatment Implications

• LMWH in full anticoagulant doses should be continued throughout pregnancy and puerperium, with mRS assessments guiding duration of therapy. 6
• The European Stroke Organization guidelines recommend parenteral anticoagulation in acute CVT, preferentially using LMWH over unfractionated heparin. 4
• LMWH demonstrates better efficacy and safety compared to unfractionated heparin, with less new intracerebral hemorrhages (adjusted OR 0.29), particularly in patients with baseline intracerebral lesions (adjusted OR 0.19). 3

Common Pitfalls to Avoid

• Do not delay mRS assessment or anticoagulation due to presence of intracranial hemorrhage—hemorrhage is not a contraindication to anticoagulation in CVT. 7
• Avoid using direct oral anticoagulants (DOACs) during pregnancy and immediate postpartum period, as guidelines suggest avoiding them despite their efficacy in non-pregnant CVT populations. 4
• Do not assume good initial mRS guarantees favorable long-term outcome—serial assessments are essential as deterioration can occur. 2
• Parenchymal lesions, thrombophilia, and antiphospholipid syndrome increase risk of neurologic sequelae regardless of initial mRS. 6