What are the causes of a hyperdynamic ejection fraction (EF) of 70%?

Causes of Hyperdynamic Ejection Fraction (EF) of 70%

A hyperdynamic left ventricular ejection fraction (LVEF) ≥70% is not a normal finding and is associated with increased mortality and diastolic dysfunction, requiring thorough evaluation for underlying causes.

Definition and Clinical Significance

A hyperdynamic heart is defined as a left ventricle with an ejection fraction above the normal range (>70%). Despite appearing "super-normal," this finding is associated with:

• Increased mortality compared to normal EF 1, 2
• High prevalence of diastolic dysfunction (78% of cases) 1
• Poorer clinical outcomes in various disease states 3, 4

Common Causes of Hyperdynamic EF

1. Hemodynamic and Cardiovascular Causes

• Severe vasodilation/low systemic vascular resistance

  • Sepsis and septic shock 4
  • Anaphylaxis
  • Cirrhosis/chronic liver disease 4
  • Arteriovenous fistulas

• Hypercontractile states

  • Hypertension (compensatory mechanism) 1
  • Early stages of hypertrophic cardiomyopathy
  • Stress-induced (catecholamine excess)

2. Pathological Conditions

• Chronic liver disease (independent risk factor, OR = 1.712) 4
• Malignancy (independent risk factor, OR = 2.784) 4
• Diastolic dysfunction (strongly associated with hyperdynamic EF) 1, 5
• Heart failure with preserved ejection fraction (HFpEF) 5

3. Physiological and Technical Factors

• Volume depletion (reduced preload)
• Tachycardia (independent risk factor) 4
• Medications
  • Vasopressors (independent risk factor, OR = 1.133) 4
  • Inotropic agents
  • Beta-agonists
• Mechanical ventilation (independent risk factor, OR = 2.141) 4

Echocardiographic Characteristics

Patients with hyperdynamic EF typically demonstrate:

• Smaller ventricular size 1
• Higher relative wall thickness 1
• Higher stroke volume and cardiac index 4
• Lower systemic vascular resistance 4
• Increased E/A ratio (marker of diastolic dysfunction) 4
• Larger left atrial volume 1
• Reduced relaxation (smaller mitral e') 1
• Higher LV end-diastolic pressures (elevated E/e' ratio) 1

Clinical Approach to Hyperdynamic EF

When encountering a patient with hyperdynamic EF:

1. Assess for diastolic dysfunction - Present in 78% of patients with hyperdynamic EF 1

   • Evaluate E/A ratio, E/e' ratio, left atrial volume
   • Consider heart failure with preserved ejection fraction (HFpEF) in symptomatic patients

2. Evaluate for underlying systemic conditions

   • Liver disease (cirrhosis)
   • Malignancy
   • Sepsis or other causes of vasodilation
   • Anemia

3. Review medications

   • Vasopressors
   • Inotropes
   • Beta-agonists

4. Monitor for adverse outcomes

   • Higher mortality risk compared to normal EF 1, 2
   • Need for more intensive monitoring

Clinical Pitfalls

1. Misinterpreting hyperdynamic EF as "healthy" - A hyperdynamic heart is not a normally functioning heart 1

2. Overlooking diastolic dysfunction - In patients with dyspnea and hyperdynamic EF without ischemia, diastolic dysfunction should be strongly considered 5

3. Failing to identify underlying systemic illness - Hyperdynamic EF can be a marker of serious conditions like sepsis or liver disease 4

4. Underestimating mortality risk - Hyperdynamic EF is associated with increased mortality in multiple studies 3, 1, 2

In conclusion, a hyperdynamic EF of 70% should prompt a thorough evaluation for underlying causes rather than being dismissed as a benign or favorable finding, as it is associated with significant diastolic dysfunction and increased mortality.