What are the features and treatment of cardiogenic shock (CS)?

From the Guidelines

Cardiogenic shock is a life-threatening condition that requires immediate intervention with a multidisciplinary approach, and the initial management should focus on identifying and treating the underlying cause, with hemodynamic support beginning with intravenous fluids, followed by vasopressors and inotropes, as recommended by the most recent guidelines 1.

Key Features of Cardiogenic Shock

• Hypotension (systolic blood pressure <90 mmHg)
• Reduced cardiac output
• Tachycardia
• Cool extremities
• Decreased urine output
• Altered mental status
• Elevated lactate levels

Treatment Approach

• Initial management: identify and treat the underlying cause, most commonly acute myocardial infarction
• Hemodynamic support:
  • Intravenous fluids if hypovolemic
  • Vasopressors: norepinephrine is the first-line vasopressor, starting at 0.01-0.3 mcg/kg/min 1
  • Inotropes: dobutamine (2.5-20 mcg/kg/min) provides inotropic support
• Mechanical circulatory support devices: may be necessary for severe cases, such as intra-aortic balloon pumps or Impella
• Revascularization: crucial for shock due to coronary occlusion, through percutaneous coronary intervention or coronary artery bypass grafting
• Continuous monitoring: vital signs, urine output, lactate levels, and hemodynamic parameters guide therapy adjustments
• Ventilatory support: may be required for respiratory distress

Importance of Early Recognition and Aggressive Treatment

• Cardiogenic shock carries a high mortality rate of 40-50% despite optimal management
• Early recognition and aggressive treatment are essential to improve outcomes
• A standardized and team-based treatment algorithm, as proposed by recent reviews 1, can help improve clinical outcomes by ensuring rapid diagnosis, early intervention, and ongoing hemodynamic assessment.

From the FDA Drug Label

The infusion should be continued until adequate blood pressure and tissue perfusion are maintained without therapy. In some of the reported cases of vascular collapse due to acute myocardial infarction, treatment was required for up to six days. Infusions of LEVOPHED are usually administered intravenously during cardiac resuscitation to restore and maintain an adequate blood pressure after an effective heartbeat and ventilation have been established by other means Prolonged administration of any potent vasopressor may result in plasma volume depletion which should be continuously corrected by appropriate fluid and electrolyte replacement therapy

The treatment of cardiogenic shock involves the use of vasopressors such as norepinephrine to restore and maintain adequate blood pressure.

• The duration of therapy should be continued until adequate blood pressure and tissue perfusion are maintained without therapy.
• Fluid intake should be managed to prevent plasma volume depletion.
• Adjunctive treatment in cardiac arrest may involve the use of norepinephrine to restore and maintain an adequate blood pressure after an effective heartbeat and ventilation have been established by other means 2.
• Dobutamine may also be used to increase heart rate and blood pressure in patients with cardiogenic shock, but it can cause increased heart rate, blood pressure, and ventricular ectopic activity 3.
• Norepinephrine can cause ischemic injury, bradycardia, arrhythmias, and stress cardiomyopathy 2.

From the Research

Features of Cardiogenic Shock

• Cardiogenic shock (CS) is a physiologic state in which cardiac pump function is inadequate to perfuse the tissues 4
• It is caused by a decline in cardiac output due to a primary cardiac disorder 5
• CS is frequently complicated by multiorgan system dysfunction that requires a multidisciplinary approach in a critical care setting 5

Diagnosis of Cardiogenic Shock

• Evaluation of patients with suspected CS should include an electrocardiogram, chest radiograph, laboratory studies, and bedside echocardiogram 4
• Diagnostic data using tools available in a modern cardiac intensive care unit should guide optimal management incorporating both pharmacologic and nonpharmacologic therapies to minimize morbidity and mortality 5

Treatment of Cardiogenic Shock

• Initial resuscitation is directed toward restoring cardiac output and tissue perfusion 4
• Mechanical circulatory support is indicated for patients with CS who do not respond to pharmacologic therapy 4
• Pharmacologic therapies include inotropes, vasopressors, and diuretics 6, 7, 8
• Norepinephrine is recommended as first-line vasopressor agent by various guidelines 7, 8
• Dobutamine is the first-line inotrope agent, whereas levosimendan can be used as a second-line agent or preferentially in patients previously treated with beta-blockers 7, 8

Pharmacologic Therapies

• Inotropes and vasopressors are widely used to improve hemodynamics acutely, but reliable information regarding comparative efficacy of individual agents is lacking 6
• The use of vasopressor and inotrope agents during cardiogenic shock is limited by their side-effects and the lack of solid evidence regarding their effectiveness in improving outcomes 6, 8
• Current information regarding comparative effective outcomes is sparse and their use should be limited as a temporary bridge to recovery, mechanical circulatory support or heart transplantation 6, 8