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Patient handout

Factor V Leiden thrombophilia DVT (heterozygous or homozygous)

PRODUCTION

1. Your condition

This handout is for factor v leiden thrombophilia dvt (heterozygous or homozygous). Your care team identified this based on: unilateral leg swelling or proven dvt in patient with strong family history of vte (first-degree relative under 50) — pretest probability for heritable thrombophilia including fvl is elevated.

Other reasons your team may use this plan: first vte under age 45 with no provoking factor — ash 2018 indication to consider heritable thrombophilia testing including fvl pcr; recurrent vte with minor or no provoking factors — strong indication for thrombophilia evaluation and likely indefinite ac; cerebral venous, splanchnic, or upper-extremity thrombosis without obvious cause → broader thrombophilia panel including fvl.

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

MedicationStarting doseHowWhenWhat it does
apixaban10 mg BID × 7 d → 5 mg BID full-dose; 2.5 mg BID extended-phase after first 6 mo if continuing indefinitePOBID × ≥3 months minimum, indefinite if homozygous/unprovoked/concurrent thrombophiliaAMPLIFY (Agnelli NEJM 2013 PMID 23808982) — apixaban first-line; AMPLIFY-EXT (Agnelli NEJM 2013 PMID 23216615) — 2.5 mg BID extended-phase preserves efficacy with lower bleed; FVL subgroup analyses show DOAC efficacy preserved
rivaroxaban15 mg BID × 21 d → 20 mg daily; 10 mg daily extended-phase after first 6 mo if continuing indefinitePOBID then daily ≥3 months, indefinite per criteriaEINSTEIN-DVT (Bauersachs NEJM 2010 PMID 21128814); EINSTEIN-CHOICE (Weitz NEJM 2017 PMID 28316279) — 10 mg daily extended-phase non-inferior to 20 mg with less bleed
edoxaban60 mg PO daily (30 mg if CrCl 15-50, weight ≤60 kg, or with strong P-gp inhibitor) after 5-10 d LMWH bridgePOdaily × ≥3 months, indefinite per criteriaHokusai-VTE (Büller NEJM 2013 PMID 23991958) — non-inferior to warfarin after LMWH lead-in
warfarin5 mg daily; INR target 2-3 (target 3 if triple-positive APS per ISTH)POdaily ≥3 months, indefinite per criteriaTRAPS (Pengo Blood 2018 PMID 30002145) — warfarin > rivaroxaban in triple-positive APS; ISTH 2020 — DOACs avoided in triple-positive APS
enoxaparin1 mg/kg SC BID; reduce to 1 mg/kg daily if CrCl <30SCBIDASH 2020 (PMID 33007077); ASH 2018 pregnancy (PMID 30482767) — LMWH first-line in pregnancy and as bridge during workup; safer if concurrent APS suspected pre-confirmation
heparin80 U/kg bolus + 18 U/kg/h targeting aPTT 1.5-2.5×IVcontinuousReversibility for acute peri-procedural management (ACCP 2021)
aspirin81 mg daily as adjunct or as fallback if AC discontinued in low-risk extended phasePOdailyWARFASA (Becattini NEJM 2012 PMID 22621626) + ASPIRE (Brighton NEJM 2012 PMID 23121403) — ASA modest VTE recurrence reduction (~30%) post-AC; inferior to extended-phase DOAC but option if patient refuses AC

Plan: Factor V Leiden thrombophilia — acute + extended-phase AC tailored to zygosity, provoking factor, and concurrent thrombophilia (ACCP 2021; ASH 2020; TRAPS 2018)

3. When to call your provider

Contact your care team if any of the following happen:

  • New VTE despite AC → reassess adherence + AC adequacy + consider switch (DOAC → warfarin if APS+)
  • Pregnancy → switch to LMWH
  • Major bleed → reverse, hold, reassess indefinite indication

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

  • Thrombophilia panel returns triple-positive antiphospholipid syndrome (lupus anticoagulant + anti-cardiolipin + anti-β2-glycoprotein I, confirmed at ≥12 weeks) on top of FVL — DOAC contraindicated, warfarin preferred
  • Pregnant patient with FVL homozygous OR heterozygous + prior VTE — high-risk pregnancy requiring antepartum + 6-week postpartum LMWH prophylaxis (or therapeutic if active DVT)
  • Homozygous FVL with first unprovoked DVT — strong indication for INDEFINITE AC (~80× lifetime VTE risk; recurrence rate ~5-10%/yr without AC)
  • Heterozygous FVL with first unprovoked DVT — individualized indefinite vs 3-mo decision; ACCP 2021 leans indefinite if low bleed risk (HAS-BLED 0-1); HERDOO2 may help in women

5. Follow-up

Genetic counseling for proband; first-degree relative screening discussion (ACMG / ASH 2018 — test only if result will change management, e.g. pre-OCP, pre-pregnancy, pre-high-risk-surgery); pregnancy planning for women (LMWH if homozygous or prior VTE); OCP discontinuation; address modifiable risk factors lifetime

6. Sources

Guideline: ACCP/CHEST 2021 (Stevens) + ASH 2018 thrombophilia testing + ASH 2020 VTE Treatment + ASH 2018 VTE in Pregnancy

  1. pubmed.ncbi.nlm.nih.gov/34352295
  2. pubmed.ncbi.nlm.nih.gov/30482764
  3. pubmed.ncbi.nlm.nih.gov/33007077