Radial access is preferred (Class 1) for PCI, and complete revascularization is Class 1 in STEMI with multivessel disease.
Pathways
Goals and Therapy of ST-Segment Elevation Myocardial Infarction/ST-Segment
PATIENT — GOAL: symptom onset to EMS call ≤5 minutes
TRANSPORT — GOAL: EMS on scene ≤8 minutes; consider prehospital fibrinolysis (when available)
MEDICAL FACILITY — DATA: focused history and physical; GOAL: ECG within ≤10 minutes. STEMI = ≥1-mm ST elevation in two contiguous leads, plus ischemic symptoms (new LBBB alone is no longer a STEMI equivalent)
Inferior MI (leads II, III, avF) → right-sided ECG (rV4) for RV MI · precordial ST depression → posterior ECG (V7, V8, V9) for posterior MI
DECISION — reperfusion plan
PRIMARY PCI — GOAL: medical contact-to-balloon ≤90 minutes. Preferred over fibrinolytics when available; also preferred for: severe congestive heart failure · cardiogenic shock · unstable ventricular arrhythmias · fibrinolytic contraindication · late presentation (>3 hours of symptoms) · STEMI diagnosis in doubt
PCI AFTER FIBRINOLYSIS: high-risk STEMI patient given fibrinolytics at a non-PCI-capable facility → arrange immediate transfer to a PCI-capable facility
FIBRINOLYTIC THERAPY — GOAL: medical contact-to-needle ≤30 minutes. Preferred when: no PCI facility available · transport delay to PCI facility · PCI contraindicated
Absolute fibrinolytic contraindications: any prior intracranial hemorrhage · ischemic stroke <3 months · known intracranial malignant neoplasm · known cerebral vascular lesion · active bleeding or bleeding diathesis · known/suspected aortic dissection · closed head or facial trauma <3 months
Relative contraindications: INR >2.0 · BP >190/110 · ischemic stroke >3 months · CPR >10 minutes · internal bleeding within 2–4 weeks · pregnancy · noncompressible vascular puncture · recent major surgery
Risk Stratification and Therapy of Non–ST-Segment Elevation Myocardial Infarction
EVALUATION — DATA: focused history and physical, ECG, cardiac biomarkers. ECG signs of ischemia: T-wave inversions >1.0 mm or ST depressions >0.5 mm
DECISION — how likely is ACS?
HIGH likelihood: ongoing rest pain >20 minutes · known CAD or MI · elevated cardiac biomarkers · new heart failure or shock · new ST depression >1.0 mm or T-wave inversion in multiple precordial leads
INTERMEDIATE likelihood: rest pain >20 minutes, now resolved · age >70, DM, male · pathologic Q waves · extracardiac vascular disease · ST depression >0.5–1.0 mm or T-wave inversion >1.0 mm · normal cardiac biomarkers
LOW likelihood: normal cardiac biomarkers · chest pain atypical or reproducible · normal ECG with angina · T-wave flattening or inversion <1 mm in leads with large R waves
ACS definite or likely?
DRUGS — absent contraindications, all patients get: aspirin 162–325 mg chewed · oral metoprolol 25–50 mg PO (routine IV metoprolol no longer recommended — harmful in shock/heart failure) q6h unless contraindicated · nitrates for active chest pain (nitroglycerin SL repeated every 5 min ×3 OR nitroglycerin IV from 10 µg/min titrated to symptoms) · consider morphine sulfate 2–4 mg IV for chest pain unresponsive to nitrates
RISK STRATIFICATION — TIMI risk score assigns 1 point each for: ≥3 coronary risk factors · age ≥65 years · known CAD (≥50% stenosis) · ≥2 chest pain episodes in 24 hours · current aspirin use · ST deviation ≥0.5 mm · elevated cardiac biomarkers
DECISION: choose management strategy
ACS unlikely — unless contraindicated give aspirin 162–325 mg chewed, with adjunctive anti-ischemic agents individualized. Once chest pain has resolved and follow-up studies are negative → stress test to provoke ischemia
Recurrent chest pain, positive follow-up studies, or positive stress test?
Go to risk stratification (TIMI score) and choose management strategy
EVALUATION — identify the trigger: H&P, ECG, hs-cTn (serial per local protocol: 0/1 h, 0/2 h, or 0/3 h) · CBC, U&E/Cr, glucose ± ABG · bedside echo if HF, murmur, RWMA, or structural disease suspected || Common triggers: sepsis · anemia/bleeding · hypoxemia · tachy-/bradyarrhythmia · HTN emergency · hypotension/shock · acute HF
Confirm Type 2 MI (rise/fall in hs-cTn + evidence of ischemia + supply–demand mismatch) — but is there persistent ischemia, dynamic ST changes, shock, or suspected plaque rupture (Type 1 MI likely)?
Treat as ACS + urgent cardiology review — manage via the STEMI/NSTEMI pathway, not this one
INITIAL MANAGEMENT — treat the trigger first: treat sepsis · correct hypoxemia · correct anemia/bleeding · restore BP/perfusion · control arrhythmias or severe HTN · treat acute HF · nitrates only if indicated and not contraindicated · reassess ECG, hs-cTn, and clinical status
ANTITHROMBOTIC THERAPY — do NOT routinely give: aspirin · P2Y12 inhibitor · UFH/LMWH · GP IIb/IIIa inhibitor · PCI || Use ONLY if: Type 1 MI suspected/confirmed · obstructive CAD requiring ACS therapy · another indication present (AF, VTE, mechanical valve)
AFTER STABILIZATION — evaluate for CAD if clinically indicated: CT coronary angiography · stress imaging · invasive angiography (choice based on clinical probability and cardiology assessment)
ICU Decoded — original critical-care and internal-medicine pathways by
Dr Javed Akhtar, each cited to a current guideline. For education and quick
reference; verify every dose against local protocols before prescribing.