靜脈血栓栓塞症

Buzzwords → Dx

Diagnostic Criteria

• Wells DVT (≥2 = likely): active cancer (1), paralysis/cast (1), bedrest >3d / surgery (1), tenderness along veins (1), leg swelling (1), calf >3 cm contralateral (1), pitting edema (1), collateral superficial veins (1), prior DVT (1), alt dx as likely (-2).
• Wells PE (>4 = likely; >6 = high): clinical signs of DVT (3), PE most likely (3), HR >100 (1.5), immobilization/surgery (1.5), prior DVT/PE (1.5), hemoptysis (1), malignancy (1).
• PERC criteria (rule out PE in low-pretest): age <50, HR <100, SaO₂ ≥95, no hemoptysis, no estrogen, no prior DVT/PE, no leg swelling, no recent surgery — all 8 = no PE workup needed.
• D-dimer: high NPV; age-adjusted (>50 yo: age × 10 ng/mL).
• Confirm DVT: compression US.
• Confirm PE: CTPA (V/Q if contrast contraindicated).

Workup

• Wells / PERC + age-adjusted D-dimer initial.
• CBC, BMP, baseline coags before anticoagulation.
• Doppler US for DVT; CTPA for PE.
• Echo / troponin / BNP for PE risk stratification (sPESI score).
• Cancer screening in unprovoked: age-appropriate screening (mammography, colonoscopy, etc.), CT C/A/P only if symptoms; routine "occult cancer search" not recommended (SOME-CT trial).
• Thrombophilia workup (selectively): unprovoked + family history + age <50 (see Thrombophilia).
• JAK2 V617F + PNH flow if splanchnic vein thrombosis.
• APS workup if recurrent VTE on therapy or arterial + venous thrombosis.

Treatment Algorithm

flowchart TD
  A[Confirmed DVT or PE] --> B{Hemodynamic status}
  B -- hemodynamically unstable<br>massive PE --> C[Systemic tPA<br>or catheter-directed thrombolysis<br>+ heparin]
  B -- stable submassive<br>RV dysfunction --> D[Anticoagulate; consider CDT in young<br>PEITHO mixed data]
  B -- stable, low-risk --> E[Anticoagulation alone]
  E --> F{Cancer-associated?}
  F -- yes --> G{GI / GU cancer?}
  G -- yes --> H[LMWH preferred<br>edoxaban acceptable; rivaroxaban higher GI bleed]
  G -- no --> I[DOAC apixaban / rivaroxaban / edoxaban<br>or LMWH]
  F -- no --> J{First episode}
  J -- provoked --> K[3 months DOAC<br>then stop]
  J -- unprovoked --> L[At least 3 months<br>then re-evaluate; HERDOO2 / DASH score<br>often indefinite if male, recurrent, residual VTE]
  J -- recurrent --> M[Indefinite anticoagulation]
  J -- APS triple-positive --> N[Warfarin INR 2-3<br>NOT DOAC<br>per TRAPS / RAPS]
  J -- catastrophic APS --> O[Anticoag + steroids + IVIG/plasmapheresis]
  K --> P{Reversal needed for bleed?}
  L --> P
  M --> P
  P --> Q[Andexanet alfa for Xa inhibitors<br>Idarucizumab for dabigatran<br>4F-PCC for warfarin/Xa<br>Vit K + 4F-PCC for major warfarin bleed]

Pearls / Pitfalls

• Triple-positive APS (LAC + anti-cardiolipin + anti-β2GPI) → WARFARIN, not DOAC. TRAPS trial showed rivaroxaban inferior in triple-positive APS. RAPS data complex; ASH 2023 supports warfarin for triple-pos APS.
• GI / GU cancers (gastric, esophageal, bladder, colorectal) — LMWH or apixaban preferred over rivaroxaban (higher major bleed in GI tract with rivaroxaban per CARAVAGGIO subgroup analyses).
• Routine occult cancer screening in unprovoked VTE (limited CT C/A/P) is NOT recommended — SOME trial showed no survival benefit, harm from incidentalomas. Age-appropriate screening only.
• Pulmonary embolism response team (PERT) — consider for submassive/massive PE. Catheter-directed therapies (EkoSonic, FlowTriever) gaining ground over systemic lysis.
• Pregnancy VTE: LMWH only (warfarin teratogenic; DOACs cross placenta). Continue postpartum × 6 wk. Mechanical valves: switch to UFH/LMWH peripartum.
• Anticoagulation duration decision tree:
  • Provoked (surgery, hospitalization): 3 mo
  • Unprovoked, first: ≥3 mo, then re-evaluate; D-dimer + residual venous obstruction + male sex push toward indefinite
  • Recurrent unprovoked: indefinite
  • Cancer-associated: anticoagulate as long as cancer is active
• HERDOO2 (women): hyperpigmentation/edema/redness in either leg, D-dimer ≥250, BMI ≥30, age ≥65 — score 0–1 may safely stop after 3 mo.
• Reversal:
  • Idarucizumab for dabigatran (Praxbind)
  • Andexanet alfa for apixaban / rivaroxaban (Xa)
  • 4-factor PCC for warfarin (or off-label Xa-inhibitors when andexanet unavailable)
  • Vitamin K for warfarin (slower; hours to onset)
  • Tranexamic acid for mucosal bleeding adjunct
• DOACs in extreme weight (BMI >40 or >120 kg) — apixaban and rivaroxaban acceptable per ISTH 2021; edoxaban / dabigatran data limited.
• Renal dose adjustments: apixaban 2.5 mg BID if 2 of 3 (age ≥80, weight ≤60 kg, Cr ≥1.5); rivaroxaban / dabigatran avoid CrCl <30; edoxaban CrCl 30–50 reduce dose.

Cross-references

• Anticoagulation — agents and reversal
• Thrombophilia — when to test
• APLA — triple-positive warfarin
• HIT — alternative anticoagulation
• PNH — splanchnic VTE screening
• PV — JAK2 + splanchnic VTE

相關題目

• Q-088 — VTE — DOAC choice in cancer-associated GI cancer
• Q-089 — VTE — triple-positive APS
• Q-090 — VTE — duration in unprovoked VTE
• Q-138 — PNH — anticoagulation duration

Sources