STEMI — antiphospholipid syndrome related (arterial APS thrombosis)
Encounter flow
10/12 authoredCanonical 12-phase frame with authored status for this dossier.
Frame
STEMI in patient with known APS or thrombosis pattern raising APS suspicion; coronary thrombosis (often more thrombus than plaque) is presenting feature
STEMI confirmed + APS suspicion or prior dx noted
Patient inputs (9)
Younger STEMI patients (<50) with thrombosis history raise APS suspicion
Contrast nephropathy + warfarin/DOAC dosing
STEMI territory localization; identical to parent
Infarct sizing + serial trend
Hemodynamic stratification + shock screen
May show fresh thrombus disproportionate to plaque; aspiration thrombectomy may be useful adjunct in this subset
APS criterion lab — must be drawn BEFORE heparin/warfarin (heparin invalidates LA assay) OR repeat ≥12 wk after AC washout
IgG + IgM aCL ≥40 GPL/MPL or >99th percentile on 2 occasions ≥12 wk apart per Sydney criteria
IgG + IgM β2-GPI >99th percentile on 2 occasions ≥12 wk apart per Sydney criteria
* = hard-required. Engine cannot meaningfully run until these are filled.
Severity triggers (4)
- informationallife_threateningcatastrophic_aps_multi_organ_thrombosisMulti-organ thrombosis (≥3 organs) in <1 wk in known/suspect APS — Catastrophic APS (CAPS); mortality 50% without aggressive triple therapyTrigger could not be auto-evaluated — needs clinician judgement.
- informationalseveredoac_exposure_error_in_known_apsPatient with known APS placed on DOAC (rivaroxaban/apixaban/edoxaban) for AC — TRAPS showed inferior outcomes vs warfarin in arterial APS subsetTrigger could not be auto-evaluated — needs clinician judgement.
- informationalseverepregnancy_in_aps_with_prior_arterial_eventPatient with prior APS-related arterial event (STEMI) becomes pregnant — warfarin teratogenic + fetal hemorrhage; need LMWH + ASA bridgeTrigger could not be auto-evaluated — needs clinician judgement.
- informationalsevererecurrent_thrombosis_on_therapeutic_warfarinRecurrent arterial or venous thrombosis despite documented therapeutic INR 2.5-3.5 — APS treatment failureTrigger could not be auto-evaluated — needs clinician judgement.
Workflow calculators
Run this disease's risk and dosing calculators inline.
Recommended regimen
APS-related STEMI long-term anticoagulation — WARFARIN preferred (NOT DOAC) per TRAPS arterial subset- aspirinfirst lineantiplatelet_cox1162-325 mg chewed → 81 mg daily LIFELONG • PO • load + daily LIFELONGtriggers: stemi_acuteAHA 2025 Class I acute + EULAR 2019 APS Class I lifelong concurrent ASA with warfarin in arterial APSrxcui 243670
- ticagrelorfirst linep2y12_inhibitor180 mg load → 90 mg BID × 12 mo • PO • BID × 12 mo DAPTtriggers: stemi_pci_plannedPLATO PMID 19717846; standard ACS DAPT applies to APS-STEMIrxcui 1116632
- heparin_unfractionatedfirst lineparenteral_anticoagulant70-100 U/kg IV bolus then infusion to aPTT 1.5-2.5×control • IV • bolus + infusiontriggers: stemi_pci, bridge_to_warfarinAHA 2025 Class I; UFH preferred over LMWH in APS for monitoring (anti-Xa more reliable than aPTT if LA prolongs baseline)rxcui 5224
- warfarinfirst linevitamin_k_antagonist5 mg daily; INR target 2.5-3.5 (HIGHER target for arterial APS vs 2-3 venous) • PO • daily LIFELONGtriggers: confirmed_aps_arterial_thrombosis, triple_positive_apsEULAR 2019 APS Class I; ASH 2018 (PMID 30482764); arterial APS — INR 2.5-3.5; LIFELONG (no taper); NEVER interrupt without bridge — interruption is leading APS thrombosis triggerrxcui 11289
- atorvastatinfirst linestatin80 mg daily • PO • dailytriggers: stemi_secondary_preventionPROVE-IT PMID 15007110; pleiotropic anti-inflammatory effect may also benefit APS endothelial dysfunctionrxcui 83367
- hydroxychloroquinecomorbidity specificantimalarial_dmard200-400 mg daily (≤5 mg/kg ideal weight) • PO • dailytriggers: sle_overlap_aps, recurrent_thrombosis_on_warfarinEULAR 2019 weak recommendation — HCQ reduces APS thrombosis risk especially with SLE overlap; consider in refractory/recurrent diseaserxcui 5521
outpatient playbook — drug actions (3)
- 1. lifelong warfarin INR 2.5-3.5rxcui 11289titrate • PO • daily LIFELONGtrigger: APS arterial thrombosisEULAR 2019 + ASH 2018 — no taper, no DOAC switch (TRAPS PMID 30196097)
- 2. lifelong ASA 81 mgrxcui 24367081 mg daily • PO • daily LIFELONGtrigger: concurrent ASA in arterial APS post-STEMIEULAR 2019
- 3. consider HCQ adjunctrxcui 5521200-400 mg daily • PO • dailytrigger: SLE overlap or refractory APSEULAR 2019 weak recommendation
Auto-drafted A&P note
outpatientSubjective
- Possible entry pathways: ST elevation on ECG in patient with known APS or triple-positive antibody profile; STEMI in young patient (<50) with prior venous thrombosis or pregnancy losses → APS suspect; Coronary cath shows thrombus burden disproportionate to atherosclerotic plaque → thrombophilia workup.
Objective
- No vitals, labs, or imaging entered for this encounter.
Assessment
**STEMI — antiphospholipid syndrome related (arterial APS thrombosis)** (cardio.stemi.antiphospholipid-syndrome-related.v1). Scope: STEMI in patient with known APS or thrombosis pattern raising APS suspicion; coronary thrombosis (often more thrombus than plaque) is presenting feature No severity triggers fired against current inputs.
Plan
Regimen axis: **APS-related STEMI long-term anticoagulation — WARFARIN preferred (NOT DOAC) per TRAPS arterial subset**. 1. aspirin 162-325 mg chewed → 81 mg daily LIFELONG PO load + daily LIFELONG (antiplatelet_cox1, first line) — AHA 2025 Class I acute + EULAR 2019 APS Class I lifelong concurrent ASA with warfarin in arterial APS 2. ticagrelor 180 mg load → 90 mg BID × 12 mo PO BID × 12 mo DAPT (p2y12_inhibitor, first line) — PLATO PMID 19717846; standard ACS DAPT applies to APS-STEMI 3. heparin_unfractionated 70-100 U/kg IV bolus then infusion to aPTT 1.5-2.5×control IV bolus + infusion (parenteral_anticoagulant, first line) — AHA 2025 Class I; UFH preferred over LMWH in APS for monitoring (anti-Xa more reliable than aPTT if LA prolongs baseline) 4. warfarin 5 mg daily; INR target 2.5-3.5 (HIGHER target for arterial APS vs 2-3 venous) PO daily LIFELONG (vitamin_k_antagonist, first line) — EULAR 2019 APS Class I; ASH 2018 (PMID 30482764); arterial APS — INR 2.5-3.5; LIFELONG (no taper); NEVER interrupt without bridge — interruption is leading APS thrombosis trigger 5. atorvastatin 80 mg daily PO daily (statin, first line) — PROVE-IT PMID 15007110; pleiotropic anti-inflammatory effect may also benefit APS endothelial dysfunction 6. hydroxychloroquine 200-400 mg daily (≤5 mg/kg ideal weight) PO daily (antimalarial_dmard, comorbidity specific) — EULAR 2019 weak recommendation — HCQ reduces APS thrombosis risk especially with SLE overlap; consider in refractory/recurrent disease Setting playbook (outpatient) — Lifelong APS management: warfarin INR 2.5-3.5, ASA 81 mg, statin, BB if EF↓; rheumatology + cardiology + hematology multidisciplinary; pregnancy planning if applicable (LMWH + ASA, NEVER warfarin in pregnancy) 7. lifelong warfarin INR 2.5-3.5 titrate PO daily LIFELONG — APS arterial thrombosis (EULAR 2019 + ASH 2018 — no taper, no DOAC switch (TRAPS PMID 30196097)) 8. lifelong ASA 81 mg 81 mg daily PO daily LIFELONG — concurrent ASA in arterial APS post-STEMI (EULAR 2019) 9. consider HCQ adjunct 200-400 mg daily PO daily — SLE overlap or refractory APS (EULAR 2019 weak recommendation) Non-pharmacologic actions: - Pregnancy planning: LMWH + ASA, hold warfarin (teratogen) - Avoid estrogen OCP/HRT - Smoking cessation absolutely critical - MedicAlert bracelet AVOID / contraindication checks: - Rivaroxaban_AVOID_in_triple_positive_aps (TRAPS PMID 30196097 — INFERIOR to warfarin for arterial events) - Apixaban_AVOID_in_arterial_aps (extrapolated from TRAPS; no DOAC RCT supports use in arterial APS) - Warfarin_target_INR_2.5 3.5_for_arterial_aps (vs 2 3 venous; EULAR 2019) - NEVER_interrupt_anticoagulation_without_bridge (interruption = APS thrombosis trigger) - Avoid_estrogen_OCP_HRT_in_aps (procoagulant, increases thrombosis risk)
Monitoring
Regimen monitoring: - INR daily during warfarin initiation then q1-2wk then q4wk (target 2.5-3.5) - anti Xa for UFH monitoring if LA prolongs baseline aPTT (LA invalidates aPTT) - CBC for thrombocytopenia (APS may have mild thrombocytopenia; HIT screen if heparin) - serial aps labs at 12 wk to confirm persistence (Sydney criteria require persistence ≥12 wk) Setting (outpatient) monitoring: - INR q4wk lifelong - Annual APS labs + lipid + A1c + creatinine Follow-up plan: Cardiology + rheumatology + hematology multidisciplinary follow-up; lifelong warfarin INR 2.5-3.5 + ASA; hydroxychloroquine if SLE overlap (may reduce APS thrombosis); avoid OCPs/HRT (estrogen worsens APS) - Close-out criterion: multidisciplinary plan + AC adherence pathway booked Monitoring phase: Serial troponin, telemetry, INR daily during warfarin initiation (target 2.5-3.5 for arterial APS), reinforce LIFELONG AC + adherence (interruption = thrombosis trigger)
Disposition
Current setting: outpatient — Lifelong APS management: warfarin INR 2.5-3.5, ASA 81 mg, statin, BB if EF↓; rheumatology + cardiology + hematology multidisciplinary; pregnancy planning if applicable (LMWH + ASA, NEVER warfarin in pregnancy) Disposition criteria: - Long-term continuation; cross-link to chronic ASCVD + rheumatology engines Escalation triggers (move to higher acuity): - Recurrent thrombosis → escalate AC intensity, add HCQ, consider rituximab (refractory CAPS) - Pregnancy → switch to LMWH + ASA immediately, rheumatology + MFM consult
Earlier-Return Triggers
Return-precaution thresholds (watch for): - [LIFE_THREATENING] Multi-organ thrombosis (≥3 organs) in <1 wk in known/suspect APS — Catastrophic APS (CAPS); mortality 50% without aggressive triple therapy - [SEVERE] Patient with known APS placed on DOAC (rivaroxaban/apixaban/edoxaban) for AC — TRAPS showed inferior outcomes vs warfarin in arterial APS subset - [SEVERE] Patient with prior APS-related arterial event (STEMI) becomes pregnant — warfarin teratogenic + fetal hemorrhage; need LMWH + ASA bridge
Citations
- 2025 ACC/AHA ACS + ESC 2023 ACS + EULAR 2019 APS Management + ASH 2018 Thrombophilia [PMID:37622670](https://pubmed.ncbi.nlm.nih.gov/37622670/) - Cited evidence (PMID 30482764) [PMID:30482764](https://pubmed.ncbi.nlm.nih.gov/30482764/) - Cited evidence (PMID 30196097) [PMID:30196097](https://pubmed.ncbi.nlm.nih.gov/30196097/) - Cited evidence (PMID 27932287) [PMID:27932287](https://pubmed.ncbi.nlm.nih.gov/27932287/) - Cited evidence (PMID 29562136) [PMID:29562136](https://pubmed.ncbi.nlm.nih.gov/29562136/) Last reconciled with current guidelines: 2026-05-15.
- 2025 ACC/AHA ACS + ESC 2023 ACS + EULAR 2019 APS Management + ASH 2018 Thrombophilia — PMID:37622670
- Cited evidence (PMID 30482764) — PMID:30482764
- Cited evidence (PMID 30196097) — PMID:30196097
- Cited evidence (PMID 27932287) — PMID:27932287
- Cited evidence (PMID 29562136) — PMID:29562136