Left main coronary artery (LMCA) STEMI-equivalent
Encounter flow
10/12 authoredCanonical 12-phase frame with authored status for this dossier.
Frame
LMCA STEMI-equivalent = aVR ST↑ ≥1 mm + diffuse ST↓ ≥1 mm in ≥6 leads pattern; HIGH mortality without urgent revasc; cardiogenic shock typical; route to cardio.stemi.core.v1 for the reperfusion arc; CABG vs PCI decision is the dominant strategic question
LMCA-equivalent ECG confirmed
Patient inputs (8)
Older patients have higher peri-revasc mortality; informs PCI vs CABG decision per SYNTAX score interaction with age
Contrast nephropathy + DOAC dosing; CKD interacts with surgical-vs-PCI decision (CABG often preferred in CKD per SYNTAX subset)
aVR ST↑ ≥1 mm + diffuse ST↓ ≥1 mm in ≥6 leads = LMCA-equivalent or proximal-LAD-pre-septal or 3VD; high mortality without urgent revasc
Confirms infarct; LMCA-territory infarcts produce massive troponin rise reflecting large jeopardized myocardium
LV function (often severely depressed); RV function; mechanical complications
Hypotension highly prevalent — LMCA territory occlusion typically produces SCAI C-E shock; informs urgent MCS need
Lactate ≥2 supports SCAI C+ shock staging — anchor for MCS escalation per DanGer Shock PMID 38587234
LMCA lesion confirmation + SYNTAX score for CABG-vs-PCI decision; LMCA bifurcation morphology for DK-CRUSH technical planning
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Severity triggers (4)
- informationallife_threateninglmca_stemi_with_cardiogenic_shockLMCA-equivalent STEMI + SBP <90 + lactate ≥2 — SCAI C+ cardiogenic shock; high probability given LMCA territory sizeTrigger could not be auto-evaluated — needs clinician judgement.
- informationallife_threateninglmca_stemi_with_biventricular_failureLMCA-equivalent STEMI + biventricular failure (RV + LV); refractory to Impella CP or escalating supportTrigger could not be auto-evaluated — needs clinician judgement.
- informationallife_threateninglmca_pci_bifurcation_complicationLMCA bifurcation PCI (left main → LAD/LCx) with side-branch occlusion or stent thrombosis intra-procedureTrigger could not be auto-evaluated — needs clinician judgement.
- informationalseverelmca_stemi_cabg_vs_pci_decisionLMCA-equivalent STEMI + Heart Team CABG-vs-PCI decision — informed by SYNTAX score, comorbidity, frailty, surgical eligibility, hemodynamic stabilityTrigger could not be auto-evaluated — needs clinician judgement.
Workflow calculators
Run this disease's risk and dosing calculators inline.
Recommended regimen
LMCA STEMI-equivalent revascularization phenotype — adds to parent cardio.stemi.core.v1 reperfusion regimen with CABG-vs-PCI strategic axis + MCS bias- aspirinfirst lineantiplatelet_cox1162-325 mg chewed • PO • load + 81 mg dailytriggers: stemi_post_roscACC/AHA 2025 ACS Class I; same as parent; do NOT hold for CABG (continue peri-CABG per AHA 2025)rxcui 243670
- ticagrelorfirst linep2y12_inhibitor180 mg load → 90 mg BID — HOLD if CABG decided within 5 d; consider cangrelor bridge • PO • BID × 12 mo if PCItriggers: stemi_pci_plannedPLATO PMID 19717846; ticagrelor washout 5 d before CABG required to mitigate bleeding (AHA 2025)rxcui 1116632
- cangrelorcomorbidity specificp2y12_inhibitor_iv_short_acting30 mcg/kg IV bolus + 4 mcg/kg/min infusion • IV • bridge to oral P2Y12 or off for CABGtriggers: cabg_likely_within_24h, oral_p2y12_not_feasibleShort half-life IV P2Y12 — useful bridge if CABG decision pending or if cardiogenic shock with absent gut absorptionrxcui 1656052
- unfractionated heparinfirst lineanticoagulant_indirect_at_iii70-100 U/kg IV bolus then per ACT • IV • titratedtriggers: pci_planned, mcs_plannedAHA 2025 Class I PCI anticoagulant; also required for Impella/ECMO MCSrxcui 5224
- metoprololcontraindication substitutebeta_blockerDEFER until shock resolves and rhythm stable • PO • deferredtriggers: post_lmca_no_cs_no_bradyBB normally Class I post-MI, but AVOID/defer if SCAI B+ shock or hemodynamic instability; reintroduce only after shock resolution + ≥48h hemodynamic stability — encoded as contraindication_substitute (avoid in acute CS phenotype, restart in chronic management arm)rxcui 6918
outpatient playbook — drug actions (1)
- 1. continue secondary-prevention bundlerxcui 243670ASA 81 + ticagrelor 90 BID × 12 mo + atorvastatin 80 + GDMT • PO • as scheduledtrigger: post-LMCA-MIAHA 2025; EXCEL for DAPT duration
Auto-drafted A&P note
outpatientSubjective
- Possible entry pathways: aVR ST↑ ≥1 mm + diffuse ST↓ ≥1 mm in ≥6 leads (LMCA equivalent / 3-vessel disease); Severe ischemic chest pain + hypotension/shock + LMCA-equivalent ECG → emergent cath + MCS standby; Known or newly identified LMCA lesion on angio in acute coronary syndrome.
Objective
- No vitals, labs, or imaging entered for this encounter.
Assessment
**Left main coronary artery (LMCA) STEMI-equivalent** (cardio.stemi.left-main.v1). Scope: LMCA STEMI-equivalent = aVR ST↑ ≥1 mm + diffuse ST↓ ≥1 mm in ≥6 leads pattern; HIGH mortality without urgent revasc; cardiogenic shock typical; route to cardio.stemi.core.v1 for the reperfusion arc; CABG vs PCI decision is the dominant strategic question No severity triggers fired against current inputs.
Plan
Regimen axis: **LMCA STEMI-equivalent revascularization phenotype — adds to parent cardio.stemi.core.v1 reperfusion regimen with CABG-vs-PCI strategic axis + MCS bias**. 1. aspirin 162-325 mg chewed PO load + 81 mg daily (antiplatelet_cox1, first line) — ACC/AHA 2025 ACS Class I; same as parent; do NOT hold for CABG (continue peri-CABG per AHA 2025) 2. ticagrelor 180 mg load → 90 mg BID — HOLD if CABG decided within 5 d; consider cangrelor bridge PO BID × 12 mo if PCI (p2y12_inhibitor, first line) — PLATO PMID 19717846; ticagrelor washout 5 d before CABG required to mitigate bleeding (AHA 2025) 3. cangrelor 30 mcg/kg IV bolus + 4 mcg/kg/min infusion IV bridge to oral P2Y12 or off for CABG (p2y12_inhibitor_iv_short_acting, comorbidity specific) — Short half-life IV P2Y12 — useful bridge if CABG decision pending or if cardiogenic shock with absent gut absorption 4. unfractionated heparin 70-100 U/kg IV bolus then per ACT IV titrated (anticoagulant_indirect_at_iii, first line) — AHA 2025 Class I PCI anticoagulant; also required for Impella/ECMO MCS 5. metoprolol DEFER until shock resolves and rhythm stable PO deferred (beta_blocker, contraindication substitute) — BB normally Class I post-MI, but AVOID/defer if SCAI B+ shock or hemodynamic instability; reintroduce only after shock resolution + ≥48h hemodynamic stability — encoded as contraindication_substitute (avoid in acute CS phenotype, restart in chronic management arm) Setting playbook (outpatient) — Long-term cardiology surveillance: secondary prevention bundle maintenance; high ICD-eligibility rate (large infarct typical); cardiac rehab completion; late surgical complications surveillance if CABG performed 6. continue secondary-prevention bundle ASA 81 + ticagrelor 90 BID × 12 mo + atorvastatin 80 + GDMT PO as scheduled — post-LMCA-MI (AHA 2025; EXCEL for DAPT duration) Non-pharmacologic actions: - ICD/WCD adherence - Cardiac rehab maintenance phase - Driving restriction per state law if VF arrest AVOID / contraindication checks: - Hold_oral_p2y12_5d_pre_cabg_to_reduce_bleeding (AHA 2025) - Beta_blocker_avoid_in_acute_cardiogenic_shock (AHA 2025) - Cangrelor_2_min_offset_acceptable_for_emergent_cabg (label) - Dapt_full_12mo_post_lmca_pci (AHA 2025 + EXCEL)
Monitoring
Regimen monitoring: - serial lactate q2-4h during mcs - arterial line throughout acute phase - echo at 24-72h for lv recovery and mcs weaning assessment - pulmonary artery catheter consideration for mcs titration Setting (outpatient) monitoring: - Quarterly + annual EF + lipid Follow-up plan: Cardiology + cardiac surgery follow-up; echo at 30-90 d for LVEF + ICD eligibility (MADIT-II); cardiac rehab; advanced HF eval if EF <30 not recovering - Close-out criterion: cardiac rehab booked + ICD pathway documented Monitoring phase: CICU/SICU telemetry + arterial line + PA catheter consideration; MCS weaning protocol; serial echo for LV recovery; vigilance for mechanical complications
Disposition
Current setting: outpatient — Long-term cardiology surveillance: secondary prevention bundle maintenance; high ICD-eligibility rate (large infarct typical); cardiac rehab completion; late surgical complications surveillance if CABG performed Disposition criteria: - Long-term continuation; cross-link to cardio.hf.core.v1 if HFrEF persists Escalation triggers (move to higher acuity): - ICD therapy delivered → urgent EP - EF declining despite GDMT → advanced HF eval / transplant - Recurrent angina → cath re-eval (in-stent restenosis or graft failure)
Earlier-Return Triggers
Return-precaution thresholds (watch for): - [LIFE_THREATENING] LMCA-equivalent STEMI + SBP <90 + lactate ≥2 — SCAI C+ cardiogenic shock; high probability given LMCA territory size - [LIFE_THREATENING] LMCA-equivalent STEMI + biventricular failure (RV + LV); refractory to Impella CP or escalating support - [LIFE_THREATENING] LMCA bifurcation PCI (left main → LAD/LCx) with side-branch occlusion or stent thrombosis intra-procedure
Citations
- 2025 ACC/AHA ACS Guideline + ESC 2023 ACS + ESC/EACTS 2018 Revascularization + SYNTAX + EXCEL + DK-CRUSH [PMID:37622670](https://pubmed.ncbi.nlm.nih.gov/37622670/) - Cited evidence (PMID 35718438) [PMID:35718438](https://pubmed.ncbi.nlm.nih.gov/35718438/) - Cited evidence (PMID 38587234) [PMID:38587234](https://pubmed.ncbi.nlm.nih.gov/38587234/) - Cited evidence (PMID 31475795) [PMID:31475795](https://pubmed.ncbi.nlm.nih.gov/31475795/) - Cited evidence (PMID 27199061) [PMID:27199061](https://pubmed.ncbi.nlm.nih.gov/27199061/) Last reconciled with current guidelines: 2026-05-14.
- 2025 ACC/AHA ACS Guideline + ESC 2023 ACS + ESC/EACTS 2018 Revascularization + SYNTAX + EXCEL + DK-CRUSH — PMID:37622670
- Cited evidence (PMID 35718438) — PMID:35718438
- Cited evidence (PMID 38587234) — PMID:38587234
- Cited evidence (PMID 31475795) — PMID:31475795
- Cited evidence (PMID 27199061) — PMID:27199061