270.2 📚 國考版

270.2.0.1 必背 — Cardiogenic Shock Definition

  • Inadequate cardiac output + tissue hypoperfusion
  • BP < 90 mmHg or vasopressor support
  • CI < 1.8-2.2 L/min/m²
  • PCWP > 15-18 mmHg
  • End-organ hypoperfusion (oliguria, altered mental status, lactic acidosis)

270.2.0.2 必背 — Etiology

  • AMI (75-80%) — most common
  • Mechanical complications (papillary muscle rupture, VSR, free wall rupture)
  • Acute decompensated HF
  • Cardiomyopathy (DCM, HCM, takotsubo, peripartum)
  • Myocarditis
  • Valvular disease (severe acute)
  • Arrhythmia
  • Cardiac tamponade
  • Massive PE
  • Post-cardiotomy
  • Sepsis-induced cardiomyopathy

270.2.0.3 必背 — SCAI Shock Classification

  • A (At Risk): at risk, no shock
  • B (Beginning): hypotension/decompensation without hypoperfusion
  • C (Classic): hypotension + hypoperfusion + vasopressor/inotrope
  • D (Deteriorating): failure of initial Tx, escalation needed
  • E (Extremis): refractory or cardiac arrest with ongoing CPR

270.2.0.4 必背 — Inotropes + Vasopressors

  • Dobutamine (first-line inotrope) — β1 + β2 agonist
  • Milrinone (PDE3 inhibitor — inotrope + vasodilator)
  • Norepinephrine (first-line vasopressor) — α1 + β1
  • Dopamine (less used now due arrhythmia — SOAP II)
  • Vasopressin (adjunct to norepinephrine)
  • Epinephrine (cardiac arrest; less for chronic)

270.2.0.5 必背 — Mechanical Circulatory Support (MCS)

270.2.0.5.0.1 IABP
  • Inflates diastole + deflates systole
  • IABP-SHOCK II — no mortality benefit
  • Less used in modern era
270.2.0.5.0.2 Impella
  • Catheter-based LV-to-aorta pump
  • DanGER-SHOCK 2024 — improved mortality in AMI + shock
  • Increasing use
270.2.0.5.0.3 VA-ECMO
  • Full cardiopulmonary support
  • Refractory shock + severe biventricular failure
  • Complications: limb ischemia, bleeding, stroke, LV distension (need decompression)
270.2.0.5.0.4 ECPELLA / BiPella
  • ECMO + Impella or biventricular Impella for severe biventricular shock

270.2.0.6 必背 — AMI + Cardiogenic Shock

  • Primary PCI + culprit-only PCI initially (CULPRIT-SHOCK trial)
  • Mechanical complications: emergent surgery (papillary muscle rupture, VSR, free wall rupture)
  • Mortality 40-50% modern era

270.2.0.7 必背 — Right Ventricular MI

  • Inferior MI + V4R ST elevation
  • Fluid resuscitation (paradoxical for hypotension)
  • Avoid nitroglycerin/morphine (decreases preload)
  • Inotrope if RV failure

270.2.0.8 必背 — Cardiac Tamponade

  • Beck’s triad: hypotension + muffled heart sounds + JVD
  • Pulsus paradoxus > 10 mmHg
  • Echocardiogram diagnostic (RA/RV collapse)
  • Emergency pericardiocentesis

270.2.0.9 必背 — Sepsis-Induced Cardiomyopathy

  • Reversible LV dysfunction in sepsis
  • Treat sepsis + supportive
  • Recovery with sepsis resolution

270.2.0.10 必背 — Shock Teams (2024 Trend)

  • Multidisciplinary team (cardio, surgery, ICU, perfusion)
  • Earlier MCS deployment
  • Improved outcomes
  • High-volume center transfer

270.2.0.11 必背 — Key Trials

  • IABP-SHOCK II (NEJM 2012): no mortality benefit IABP
  • CULPRIT-SHOCK (2017): culprit-only PCI in multivessel + shock
  • DanGER-SHOCK (2024): Impella improves mortality in AMI + shock
  • SOAP II: norepinephrine vs dopamine — less arrhythmia, similar mortality