What are the recommended vasopressors for treating cardiogenic shock?

Vasopressors in Cardiogenic Shock

Primary Recommendation

In cardiogenic shock, inotropes (dobutamine, dopamine, or phosphodiesterase III inhibitors) are the first-line agents, with norepinephrine added only when persistent hypotension remains despite inotropic therapy and fluid resuscitation. 1

Initial Management Strategy

First-Line Therapy: Inotropes

• Dobutamine is the recommended first-line agent for cardiogenic shock to increase cardiac output in patients with poor myocardial function 1, 2, 3
• Dopamine may be considered specifically in patients with bradycardia or low risk for tachycardia 1
• Phosphodiesterase III inhibitors (milrinone, enoximone) are alternative first-line options, particularly effective in patients on chronic beta-blocker therapy 1

When to Add Vasopressors

Norepinephrine should be added only when the combination of inotropic therapy and fluid challenge fails to restore systolic blood pressure >90 mmHg with persistent signs of inadequate organ perfusion 1, 4, 5, 2, 3

The rationale is that cardiogenic shock typically presents with high systemic vascular resistance, making pure vasopressors potentially harmful by further increasing afterload and myocardial oxygen consumption 1

Specific Clinical Scenarios

Persistently Hypotensive Cardiogenic Shock with Tachycardia

• Norepinephrine is the preferred vasopressor when blood pressure support is needed 1, 4, 5, 2, 3
• Should be administered through a central line 1
• Target mean arterial pressure ≥65 mmHg 1

Cardiogenic Shock with Bradycardia

• Dopamine may be preferred as it provides both inotropic support and chronotropic effects 1

Afterload-Dependent States (Aortic Stenosis, Mitral Stenosis)

• Phenylephrine or vasopressin is advised as these pure vasoconstrictors avoid increasing contractility that could worsen outflow obstruction 1
• Vasopressin may be particularly useful in patients with right ventricular failure and pulmonary hypertension 5, 3

Critical Warnings

Agents to Avoid

Epinephrine is explicitly NOT recommended as an inotrope or vasopressor in cardiogenic shock and should be restricted to cardiac arrest only 1, 6

• Associated with increased incidence of refractory shock 3
• Observational data suggest increased mortality risk 3
• Recent meta-analysis indicates norepinephrine is preferred over epinephrine in cardiogenic shock, particularly post-myocardial infarction 5, 2

Important Caveat on Norepinephrine

Despite guideline recommendations, a 2022 retrospective cohort study of 927 cardiogenic shock patients found norepinephrine use was associated with significantly increased 30-day mortality (41% vs 30%, OR 1.61, P=0.017) 7. This suggests norepinephrine should be used judiciously and discontinued as soon as hemodynamically feasible 1

Alternative and Second-Line Agents

Levosimendan

• Consider as an alternative or additional agent when dobutamine fails to restore adequate perfusion 1, 2, 3
• Particularly effective in patients on chronic beta-blocker therapy as its mechanism is independent of beta-adrenergic stimulation 1
• Administered as 0.05-0.2 mcg/kg/min infusion for 24 hours; avoid loading dose if systolic BP <100 mmHg 1

Vasopressin

• May be added to reduce norepinephrine requirements at doses up to 0.03 units/min 1
• FDA-approved for vasodilatory shock at 0.01-0.07 units/minute for septic shock and 0.03-0.1 units/minute for post-cardiotomy shock 8
• Particularly useful in tachycardic patients or those with pulmonary hypertension 5, 3

Phenylephrine

• Reserved for salvage therapy only 1

Monitoring Parameters

Hemodynamic Targets

• Systolic blood pressure >90 mmHg 1, 6, 9
• Mean arterial pressure ≥65 mmHg 1, 10, 6
• Cardiac index >2 L/min/m² 10, 9

Perfusion Markers

Complement blood pressure targets with serial assessment of:

• Urine output 1, 6, 9
• Serum lactate clearance 1, 6, 9
• Mixed or central venous oxygen saturation 1, 9
• Mental status 1, 6, 9
• Skin perfusion 1

Common Pitfalls

• Do not use vasopressors as first-line agents - always optimize volume status and initiate inotropes first 1
• Discontinue all vasopressors as soon as possible due to their propensity to increase myocardial oxygen demand and risk of arrhythmias 1
• Avoid combining multiple high-dose inotropes - instead consider mechanical circulatory support 10, 9
• Use caution with all vasopressors as cardiogenic shock typically involves high systemic vascular resistance 1
• Individualize MAP goals as the risk of hypoperfusion must be balanced against negative impacts on cardiac output, myocardial oxygen consumption, and arrhythmias 1