Cath-lab decision console

ACS rapid route

clock running

Active pathwayNode 1

First contact

≤10 min

12-lead ECG

Repeat if nondiagnostic and symptoms persist. Add right-sided leads for inferior MI; posterior leads when posterior ischemia is suspected.

Primary PCI

≤90 min

FMC-to-device

Target at a PCI-capable hospital. If transfer is required, choose PCI when expected FMC-to-device is ≤120 min.

If PCI delay & eligible

≤30 min

Fibrinolysis

Door-to-needle target, usually within 12 h of symptom onset. Transfer after lysis; rescue PCI for failed reperfusion.

NSTE-ACS unstable

<2 h

Immediate invasive

Shock/hemodynamic instability, recurrent refractory pain, life-threatening arrhythmia, or mechanical complication.

NSTE-ACS high risk

<24 h

Early invasive

Established NSTEMI, dynamic ST/T changes, or high GRACE risk (classically >140).

Biomarker lane

0/1 h

hs-cTn algorithm

Use assay-specific 0/1-h or 0/2-h delta pathways. A single value is not enough when presentation is early or suspicion remains high.

ANTIPLATELET

Aspirin + P2Y12 inhibitor

Aspirin loading: 162–325 mg chewed, then maintenance (commonly 75–100 mg/day).

Add ticagrelor, prasugrel, or clopidogrel according to strategy and bleeding risk. Prasugrel: avoid with prior stroke/TIA; generally use after coronary anatomy is known and PCI planned.

ANTICOAGULATION

Parenteral anticoagulant

Options include UFH, enoxaparin, bivalirudin, or fondaparinux depending on STEMI/NSTE-ACS strategy, PCI, renal function, and bleeding risk.

Trap: fondaparinux alone is inadequate during PCI—add an anti-IIa agent such as UFH to prevent catheter thrombosis.

ANTI-ISCHEMIC

Relieve ischemia safely

Nitroglycerin for ongoing pain/hypertension unless hypotension, suspected RV infarction, severe aortic stenosis, or recent PDE-5 inhibitor use.

Beta-blocker within 24 h if no acute HF, low-output state, shock risk, bradycardia, or heart block.

SECONDARY PREVENTION

Start early

High-intensity statin for all unless contraindicated. ACE inhibitor/ARB especially with LVEF ≤40%, anterior MI, hypertension, diabetes, or CKD. Add aldosterone antagonist when indicated.

OXYGEN

Not routine

Give oxygen for hypoxemia—commonly SpO₂ <90%—or respiratory distress. Routine oxygen in a normoxemic patient offers no benefit.

FIBRINOLYSIS

STEMI only

Use when timely PCI is unavailable and no contraindication exists. Pair with antiplatelet and anticoagulant therapy, then transfer to a PCI center.

Never use fibrinolysis for NSTEMI or unstable angina.

Troponin must not delay STEMI reperfusion.

A diagnostic STEMI ECG is enough to activate the cath lab. Biomarkers can be drawn, but do not wait for the result.

NSTEMI vs unstable angina is a biomarker distinction.

Both can have ischemic symptoms and ST depression/T-wave inversion. NSTEMI has acute myocardial injury (rise/fall with ≥1 value above the assay’s 99th percentile); UA does not.

A normal first ECG or troponin does not rule out ACS.

Repeat ECGs and serial hs-cTn are required when symptoms persist, presentation is early, or clinical suspicion is high.

Posterior MI can hide as anterior ST depression.

ST depression maximal in V1–V3 with tall R waves suggests posterior STEMI equivalent—obtain V7–V9.

Inferior MI? Think right ventricle before nitrate.

Check V3R–V4R. RV infarction is preload-dependent; nitrates can precipitate profound hypotension.

New LBBB alone is not automatically STEMI.

Use symptoms, hemodynamics, prior ECG, and validated concordance criteria such as modified Sgarbossa to assess acute occlusion.