Clinical Commander

All dossiers
cardio.dvt.distal.v1

Distal DVT (isolated calf vein)

cardiologyacuteadultacutetransitionoutpatient
Start encounter →Print handoutPRODUCTION

Phase E variant of cardio.dvt.core.v1 — narrowed to distal (isolated calf vein) DVT (IDDVT). Inherits diagnostic arc from parent via routing; specializes for AC vs surveillance decision (the central IDDVT controversy), shorter 6-12 week AC duration when chosen, and serial US strategy for extension monitoring per Righini 2009 + ACCP 2021. Manifest pointer reuses cardio.dvt.core.v1 manifest. Design-brief pointer reuses parent (IDDVT-specific differences documented inline). CACTUS (PMID 27836513) showed no benefit of nadroparin in low-risk symptomatic IDDVT — supports surveillance pathway when bleed risk is meaningful. Extension to popliteal converts management to cardio.dvt.proximal.v1 pathway. Status INTEGRATED. Authored 2026-05-14 by shard-06-cardio-acute as distal-DVT variant.

Entry points (3)

  • symptom
    Isolated calf pain, swelling, tenderness without thigh involvement → suggests distal DVT
    isolated_calf_pain_swelling
  • imaging
    Compression US shows non-compressible distal vein (peroneal, posterior tibial, soleal) with patent popliteal/femoral → isolated distal DVT (IDDVT)
    us_distal_thrombus_only
  • history
    Whole-leg compression US identifies isolated distal DVT not detected by proximal-only protocol (Bernardi 2008)
    whole_leg_us_screening_finding

Required inputs (7)

  • agerequired
    demographic • used at CONTEXT
    Older patients higher recurrence + extension risk → favors AC over surveillance
  • symptom_burdenrequired
    symptom • used at ENTRY
    Severe symptoms favor AC for symptom relief; mild symptoms allow surveillance
  • compression_us_distalrequired
    imaging • used at INITIAL_WORKUP
    Whole-leg US confirms isolated distal location; serial US for surveillance strategy (Righini JTH 2009 PMID 38546285)
  • d_dimer
    lab • used at RISK_STRATIFICATION
    Persistently elevated D-dimer is risk factor for extension → favors AC (CACTUS PMID 27836513 subgroup analyses)
  • creatininerequired
    lab • used at TREATMENT
    eGFR for DOAC dosing if AC chosen
  • extension_risk_factorsrequired
    history • used at RISK_STRATIFICATION
    Extension risk factors: positive D-dimer, extensive thrombus burden, persistent provoking factor, prior DVT, active cancer, hospitalization (ACCP 2021)
  • bleed_riskrequired
    history • used at RED_FLAGS
    HAS-BLED determines tolerability of AC vs surveillance

12-phase flow (10)

  1. 1FRAME
    Distal (isolated calf) DVT — anticoagulation vs serial US surveillance is the central decision; lower extension/PE risk than proximal DVT but extension occurs in ~15% within 2 weeks
    inputs: symptom_burden
    advance: distal location confirmed
  2. 2ENTRY
    Wells score, D-dimer, US — confirm isolated distal location with patent popliteal vein
    inputs: age
    advance: IDDVT confirmed on imaging
  3. 3CONTEXT
    Provoked vs unprovoked, persistent risk factors, cancer status, prior VTE history
    inputs: extension_risk_factors
    advance: risk profile documented
  4. 4RED_FLAGS
    Active malignancy, prior VTE, persistent provoking factor, extensive thrombus burden, hospitalized — all favor AC over surveillance; AC contraindication (active bleed) favors surveillance
    inputs: bleed_risk
    advance: high-risk features for extension assessed
  5. 5INITIAL_WORKUP
    Whole-leg compression US (per Bernardi 2008 if proximal-only US negative); CBC + BMP
    inputs: compression_us_distal, creatinine
    actions: panel.cardiac, panel.renal
    advance: imaging + labs documented
  6. 6RISK_STRATIFICATION
    Stratify extension risk: low (asymptomatic, single-vein, neg D-dimer, no risk factors) → surveillance; high (extensive thrombus, persistent factor, cancer, prior VTE, severe symptoms, hospitalized) → AC
    inputs: d_dimer
    advance: AC vs surveillance decision made
  7. 7TREATMENT
    Path A (AC chosen): DOAC × 6-12 weeks (apixaban or rivaroxaban full dose). Path B (surveillance chosen): serial compression US at days 5-7 and 10-14; if extension to popliteal → convert to proximal DVT pathway
    inputs: creatinine
    advance: pathway initiated
  8. 8DISPOSITION
    Outpatient management standard; surveillance pathway requires reliable follow-up + return precautions
    advance: follow-up booked
  9. 9MONITORING
    AC pathway: bleed surveillance, weekly CBC × 4 weeks. Surveillance pathway: repeat US days 5-7 + 10-14 + symptoms
    actions: panel.cardiac
    advance: surveillance plan documented
  10. 10FOLLOWUP
    AC pathway: stop at 6-12 weeks if provoked + transient risk; consider extended only if extension or unprovoked + high recurrence risk. Surveillance pathway: convert to proximal pathway if extension
    advance: final disposition documented