Cardiogenic shock
Cardiogenic shock is primary cardiac pump failure that produces sustained hypotension and end-organ hypoperfusion despite adequate filling, most often from a large acute myocardial infarction. Survival depends on emergently reversing the cause, usually by revascularization, while supporting perfusion with vasopressors, inotropes, and, when refractory, mechanical circulatory support.
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What this article covers
- Overview
Definition: cardiogenic shock is a state of primary cardiac pump failure that causes sustained hypotension and end-organ hypoperfusion despite adequate intravascular volume.
- Epidemiology
Leading cause is acute MI: cardiogenic shock complicates a minority of myocardial infarctions but is the leading cause of in-hospital death after MI.
- Risk factors
Large or anterior myocardial infarction: extensive left ventricular damage is the dominant substrate.
- Pathophysiology
Pump failure lowers output: a primary drop in cardiac output and cardiac index produces systemic hypoperfusion.
- Clinical features
Hypotension: systolic blood pressure below 90 mmHg or dependence on pharmacologic or mechanical support.
- Differential diagnosis
Hypovolemic shock: hypotension with a history of bleeding or fluid loss, showing low jugular venous pressure and a brisk response to fluid resuscitation rather than the high filling pressures of pump failure.
- Diagnosis
Establish clinically and hemodynamically: cardiogenic shock is defined by sustained hypotension (systolic blood pressure below 90 mmHg for at least 30 minutes, or vasopressor or mechanical support…
- Management
First, reverse the cause: in acute-coronary-syndrome shock, emergent revascularization by primary PCI (or CABG) is the single most survival-improving intervention, especially in patients younger than…
- Complications
Multiorgan failure and death: acute kidney injury, hepatic injury, and mesenteric infarction from sustained hypoperfusion.
- Prognosis
Historically severe: mortality of 50 to 80 percent, markedly improved by early recognition and emergent revascularization.
- Prevention
Timely reperfusion of STEMI: a door-to-balloon time of 90 minutes or less limits infarct size and is the main way to prevent shock.
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