Cardiogenic Shock

Perfusion: BP / pulse, mentation, extremity temperature, capillary refill, and urine output. Cool / clammy skin, confusion, or oliguria raises concern—even with a preserved BP.

Breathing: Respiratory effort, SpO₂, crackles, and fatigue. Establish monitoring / IV access; oxygen for hypoxemia.

Assess lactate, creatinine, and liver-function trends. Low EF or edema alone does not establish shock. See Recognition.

History / Exam: Chest pain, recent MI, known HF, palpitations; assess rhythm, JVP, edema, crackles, and a new murmur.

ECG: Ischemia / infarction, tachyarrhythmia, bradycardia, or AV block?

Cardiac / Lung POCUS: LV versus RV dysfunction, major valve abnormality, pericardial effusion, and pulmonary congestion. Obtain urgent formal echo when needed.

Consider PE, tamponade, sepsis, or hemorrhage when the findings do not fit isolated pump failure. See Evaluation.

Hypotensive With Hypoperfusion: Start norepinephrine; titrate to pressure and organ response.

Adequate BP, Persistent Low Output: Reassess filling and cardiac function; consider dobutamine. Some patients require both pressure and inotropic support.

Congested: Elevated JVP, edema, or pulmonary congestion → consider IV loop diuresis while maintaining perfusion. Hypotension does not automatically indicate a fluid deficit.

Underfilled: A small fluid challenge may be appropriate when the assessment supports it; reassess immediately, especially with RV dysfunction. See Fluids Or Diuresis.

Respiratory Failure: Consider CPAP / BiPAP for pulmonary edema when airway protection and hemodynamics permit. Intubate for failing oxygenation / ventilation or airway protection; prepare circulatory support before induction. See Airway.

ACS With Shock: Urgent coronary evaluation / revascularization pathway.

Causative Unstable Rhythm: Cardioversion, pacing, or rhythm-specific treatment.

New Murmur / Abrupt Post-MI Deterioration: Urgent echo and cardiac surgical assessment for a mechanical complication.

Persistent hypoperfusion or escalating infusions → reassess the cause; arrange shock-center transfer / selected mechanical support. See Definitive Treatment.

Recheck mentation, skin perfusion, urine output, BP, respiratory support, and lactate trend. A better BP without better perfusion is an incomplete response.

Cath Lab / OR: Time-sensitive coronary or mechanical intervention.

ICU / Shock Center: Ongoing shock, vasoactive infusions, or advanced support. See Disposition.

Cardiogenic shock is inadequate circulation from cardiac dysfunction with clinical or biochemical evidence of tissue hypoperfusion.

BP: SBP <90 or MAP <65 mm Hg raises concern, but hypotension is not required. Compensatory vasoconstriction can preserve BP despite inadequate flow.

EF: A chronically low EF does not establish shock; preserved LV EF does not exclude RV failure or an acute mechanical problem.

Assess the current physiology and trajectory rather than the HF diagnosis alone. ACC 2025.

Brain: New confusion, agitation, lethargy, or reduced responsiveness.

Skin: Cool / clammy extremities, delayed capillary refill, mottling, weak pulses.

Kidneys: Falling urine output, oliguria, or rising creatinine.

Liver / Metabolic: Rising transaminases, lactate, or metabolic acidosis.

Interpret trends against baseline. These findings are supportive, sometimes late, and not individually diagnostic; renal / hepatic abnormalities may also reflect congestion. ACC 2025 · AHA — Right Heart Failure.

Reassess the stage as treatment proceeds. Classification communicates severity; it does not replace the cause-specific assessment or require every listed laboratory abnormality. SCAI 2022.

ACS: Chest discomfort, ischemic ECG findings, or unexplained acute ventricular dysfunction. Both STEMI and NSTEMI may cause shock.

Dysrhythmia: Sustained tachyarrhythmia, marked bradycardia, or high-grade AV block contributing to poor output.

Mechanical / Valve: Abrupt deterioration after MI, new murmur, or sudden pulmonary edema → assess acute MR, ventricular septal rupture, or another major valve lesion.

Pump Failure: Acute decompensated cardiomyopathy, myocarditis, or other acute myocardial dysfunction.

Alternative / Mixed Shock: Sepsis with myocardial dysfunction, hemorrhage, PE, or tamponade. A poor EF does not establish the entire explanation. ACC 2025 · AHA — Mechanical Complications.

Review onset, chest symptoms, prior HF / coronary or valve disease, recent MI / procedure, medications, and baseline function.

Assess perfusion alongside JVP, crackles, edema, rhythm, and murmurs.

Congestion and perfusion are separate assessments. A patient may be congested yet adequately perfusing, congested and shocked, or hypoperfused without prominent lung findings. AHA/ACC/HFSA 2022.

ECG: Ischemia / infarction, ventricular arrhythmia, bradycardia, or conduction block; compare prior tracings. Consider right-sided leads with suspected RV infarction.

LV: Global versus regional dysfunction; assess chamber size and major valve abnormalities.

RV: Size, contractility, and septal position; assess RV-dominant or biventricular failure.

Pericardium / Lungs: Effusion with possible tamponade physiology, B-lines, pleural fluid, or an alternative pulmonary problem.

Obtain urgent formal echocardiography when valve anatomy, mechanical disease, or the hemodynamic explanation remains uncertain. RV dilation alone does not diagnose PE; pericardial fluid alone does not diagnose tamponade. ACC 2025 · AHA — Right Heart Failure.

Obtain CBC, electrolytes / renal function, magnesium, liver tests, lactate, and troponin; blood gas when respiratory failure or significant acidosis is present.

Troponin supports myocardial-injury assessment; interpret with ECG, symptoms, and trajectory rather than diagnosing ACS from the value alone.

Consider CXR for congestion / another pulmonary diagnosis and cultures / infectious testing when mixed septic shock is plausible.

Do not delay time-sensitive coronary or mechanical intervention for a complete laboratory panel. ACC 2025.

Low output: The circulation may maintain BP through vasoconstriction while organ blood flow remains inadequate.

Vasopressor: Supports arterial pressure; excessive vasoconstriction can also increase the failing ventricle’s workload.

Inotrope: Supports contractility / output; dobutamine and milrinone can also lower vascular resistance and BP.

Practical implication: Hypotension may require norepinephrine, persistent low output may require an inotrope, and some patients require both. A better MAP without better perfusion is an incomplete response. ACC 2025 — Pharmacologic Management.

A reasonable initial vasopressor for most hypotensive cardiogenic-shock patients; not a medication every patient with low EF needs.

Example start: 0.05–0.1 mcg/kg/min IV, titrated to pressure and perfusion. This is a starting range, not a maximum; follow standardized infusion / monitoring protocols.

Initial MAP around 65 mm Hg is a practical starting goal, then individualize to baseline pressure and organ response.

Use the lowest effective dose; persistent hypoperfusion despite restored pressure requires reassessment of output, congestion, and the cause. ACC 2025.

Dobutamine: Consider when inadequate cardiac output persists after pressure and filling have been assessed. An example starting infusion is 2.5–5 mcg/kg/min IV, titrated to response.

Watch for tachyarrhythmia, ischemia, and hypotension; concurrent norepinephrine may be necessary.

Milrinone: A selected alternative with inotropic and vasodilator effects. Its longer action and renal accumulation make titration less forgiving in hypotension / AKI; dosing requires renal and hemodynamic assessment. AHA/ACC/HFSA — IV Inotropes.

DOREMI: In 192 patients, milrinone did not significantly improve the primary composite outcome compared with dobutamine. Neither is a proven universal winner. Mathew 2021.

Epinephrine: Remains a selected rescue option, but not the default substitute for norepinephrine. A small post-MI shock trial found more refractory shock and lactic acidosis with epinephrine; it did not settle every clinical scenario. OptimaCC 2018.

Vasodilators: Selected patients with adequate pressure and excessive afterload may benefit under closely monitored specialist care; avoid carrying the hypertensive pulmonary-edema nitrate pathway into hypotensive shock.

Pure Vasoconstriction: Phenylephrine may raise BP while worsening output; it is not the usual primary infusion for pump failure. ACC 2025.

Underfilled: Consider a small crystalloid challenge only when the history / examination / echo supports inadequate filling. For example, 250 mL followed by immediate reassessment—not automatic repeated liters.

Congested And Perfusing: Treat congestion with IV loop diuretics; this may be decompensated HF without cardiogenic shock.

Congested And Hypoperfused: Support pressure / output and address congestion together. Diuretics alone may be insufficient, but hypotension does not automatically mean the patient needs fluid. AHA — Right Heart Failure.

Why kidney function may improve: Lower venous pressure can relieve renal congestion and improve the pressure gradient through the kidney. More fluid may worsen that problem; a rising creatinine does not independently establish dehydration. AHA — Cardiorenal Syndrome.

Follow BP, perfusion, urine output, electrolytes, and congestion. Reassess a creatinine rise in context rather than reflexively stopping decongestion or adding fluid. AHA/ACC/HFSA — Decongestion.

The RV needs adequate filling, but a distended RV may already be overfilled. Additional volume can worsen septal shift, reduce LV filling, and lower output.

Assess volume status, RV function, pulmonary pressures / suspected cause, and perfusion. Select fluid, decongestion, and vasoactive support accordingly.

Correct hypoxemia and significant acidemia; avoid unnecessary increases in intrathoracic pressure. RV infarction needs coronary treatment; PE requires the obstructive-shock / reperfusion pathway.

Uncertain or refractory RV failure warrants early specialist input and consideration of invasive hemodynamics. AHA — Right Heart Failure.

Treat hypoxemia and excessive respiratory effort. Consider CPAP / BiPAP for pulmonary edema when airway protection, cooperation, and hemodynamics permit.

The strong NIV evidence for pulmonary edema does not automatically apply to cardiogenic shock: These patients were generally excluded from the trials. Reassess BP and perfusion immediately after positive pressure begins. ERS/ATS — Cardiogenic Pulmonary Edema.

Intubation: Failed oxygenation / ventilation, exhaustion, or loss of airway protection. Induction and positive pressure can precipitate collapse; prepare hemodynamic support, preoxygenate, and use an experienced airway team.

Follow the RSI pathway. Do not delay necessary airway control, but do not intubate solely because shock is present. ACEP — Endotracheal Intubation.

ACS With Shock: Emergency coronary angiography / culprit-vessel revascularization when indicated. Routine treatment of additional nonculprit vessels during the same shock procedure is not the preferred strategy. ACC/AHA — ACS 2025.

Unstable Dysrhythmia: Cardioversion, pacing, or appropriate rhythm treatment. Distinguish a causative arrhythmia from compensatory sinus tachycardia.

Mechanical Complication: Suspected papillary muscle rupture / acute severe MR, septal rupture, or free-wall rupture → immediate echo and cardiac surgical / structural-heart assessment. Pressors do not repair a mechanical lesion. AHA — Mechanical Complications Of MI.

Nonischemic Pump Failure: Early advanced-HF / shock-team involvement; assess recovery potential and the need for temporary support. ACC 2025.

Escalating vasopressor / inotrope requirements, persistent oliguria, worsening mentation / acidosis, or recurrent arrhythmia: Reassess the cause and activate the shock team / transfer pathway.

Consider a pulmonary artery catheter when bedside findings do not adequately define LV versus RV failure, filling pressures, or response to treatment.

Invasive measurements can direct fluid removal, inotropes, and device selection. They supplement clinical assessment; do not delay immediate treatment or transfer for a catheter. AHA/ACC/HFSA — Cardiogenic Shock · ACC 2025.

Consider when adequate organ perfusion cannot be maintained with initial treatment or selected high-risk anatomy / physiology warrants earlier support. Device choice depends on LV, RV, or biventricular failure, oxygenation, anatomy, and the intended bridge to recovery or further therapy.

Microaxial LV Pump: An option for selected infarct-related shock—not an automatic device for every low EF or hypotensive patient.

• DanGer-Shock: Among 355 analyzed STEMI-shock patients, 180-day mortality was 45.8% versus 58.5% with pump versus standard care. The composite safety outcome was 24.0% versus 6.2%. Benefit and harm both matter; this was not an all-comers HF population. Møller 2024.

VA-ECMO: Provides circulatory and oxygenation support, but routine early use in infarct-related shock did not improve 30-day survival in ECLS-SHOCK and increased bleeding / vascular complications. Selected rescue remains a separate decision. Thiele 2023.

IABP: Not an automatic step for undifferentiated cardiogenic shock; may have a selected bridging role, including certain mechanical complications. AHA — Mechanical Complications.

Reassess mentation, skin perfusion, urine output, MAP, respiratory support, and vasoactive requirements after changes.

Trend lactate, creatinine, electrolytes, acid–base status, and liver tests according to severity. Repeat focused echo when the response is unexpected.

Consider invasive arterial pressure monitoring for ongoing shock / titrated infusions. Reassess mixed physiology and unresolved ischemia, obstruction, or mechanical disease when support requirements rise.

A better BP with persistent organ hypoperfusion is not successful resuscitation. ACC 2025 — Reassessment.

Coronary ischemia or a mechanical lesion requiring immediate intervention.

Arrange definitive treatment while supporting circulation; ICU admission must not delay a needed procedure. ACC/AHA — ACS 2025 · AHA — Mechanical Complications.

Ongoing hypoperfusion, vasoactive infusions, advanced respiratory support, unstable rhythms, or mechanical-support consideration.

Transfer early when the required cardiac / surgical support is unavailable locally. Communicate the cause, LV / RV findings, SCAI stage, trajectory, current infusions, and treatment response.

Clarify goals of care and the purpose of escalation while continuing indicated resuscitation. ACC 2025 — Shock Teams / Transfer.

Appropriate for selected preshock patients or after sustained resolution of shock, depending on residual risk and local monitoring capability.

Confirmed cardiogenic shock requires inpatient care; an initially improved BP is not an ED discharge criterion. AHA/ACC/HFSA 2022.