Is a high ejection fraction on an echocardiogram concerning in an asymptomatic adult?

High Ejection Fraction on Echo: Clinical Significance

A high ejection fraction (>70-75%) on echocardiogram in an asymptomatic adult is generally not concerning and typically represents normal or hyperdynamic cardiac function, though it warrants evaluation for underlying causes such as hypertrophic cardiomyopathy, restrictive cardiomyopathy, or conditions causing hyperdynamic states.

Understanding Normal EF Ranges

The normal left ventricular ejection fraction ranges from approximately 52-73% in the general population 1. Importantly:

• Women have slightly higher normal EF (mean 63.7%, lower limit 52.7%) compared to men (mean 61.9%, lower limit 51.7%) 1
• Asian individuals tend to have 2-3 percentage points higher EF than Black or White individuals 1
• Age does not significantly affect normal EF values 1

An EF above the upper normal limit (~73%) represents hyperdynamic function, which is qualitatively described in echocardiographic reporting 2.

When High EF May Signal Pathology

While hyperdynamic function itself is not inherently dangerous, it can be a marker of specific cardiac conditions that require further evaluation 3:

Hypertrophic Cardiomyopathy (HCM)

• May present with preserved or supranormal EF despite significant underlying dysfunction
• The key issue is diastolic dysfunction and elevated filling pressures, not systolic function 3
• Global longitudinal strain (GLS) is markedly depressed even when EF appears normal or high 3
• Must evaluate for LV outflow tract obstruction using continuous wave Doppler 3
• Look for asymmetric septal hypertrophy, systolic anterior motion of mitral valve, and dynamic LVOT gradients

Restrictive Cardiomyopathy

• Typically shows normal ventricular size and preserved systolic function with atrial enlargement 4
• Characteristic Doppler inflow patterns indicate diastolic dysfunction 4
• In infiltrative diseases (amyloidosis), may see stippled myocardial appearance 4

Hyperdynamic States (Non-pathologic)

• High-output states: anemia, hyperthyroidism, arteriovenous fistulas
• Volume depletion or reduced preload
• Hyperadrenergic states
• Athletic conditioning

Critical Concept: EF Doesn't Tell the Whole Story

The most important clinical principle: Patients can have heart failure and poor outcomes despite preserved or even elevated EF 3. The 2015 European guidelines emphasize that "the main determinant of cardiac symptoms and prognosis is represented by the increase in LV filling pressure" 3, not ejection fraction alone.

Advanced Assessment Beyond EF

When EF is high or preserved, evaluate:

1. Global Longitudinal Strain (GLS) 3:

   • Values <-16% indicate mild dysfunction
   • Values <-10% indicate severe dysfunction
   • Can detect early systolic dysfunction before EF declines
   • Particularly valuable in HCM and restrictive cardiomyopathy

2. Diastolic Function Parameters 3:

   • E/e' ratio (lateral) >10-11 suggests elevated filling pressures
   • Left atrial volume index ≥34 mL/m²
   • Mitral inflow patterns (E/A ratio, deceleration time)
   • Pulmonary artery pressures

3. Structural Assessment:

   • Wall thickness and LV mass
   • Chamber dimensions
   • Valvular function
   • Regional wall motion abnormalities

Clinical Approach to Asymptomatic High EF

Step 1: Confirm the Finding

• Ensure adequate image quality and proper measurement technique
• Verify using biplane Simpson's method when possible 5

Step 2: Assess for Structural Disease

• Measure wall thickness (look for hypertrophy)
• Evaluate chamber sizes
• Assess valve structure and function
• Look for regional wall motion abnormalities

Step 3: Evaluate Diastolic Function

• Obtain mitral inflow velocities (E, A)
• Measure tissue Doppler velocities (e', a')
• Calculate E/e' ratio
• Measure left atrial volume index

Step 4: Consider Advanced Imaging

• If HCM suspected: Obtain GLS, assess for LVOT obstruction, consider cardiac MRI
• If restrictive pattern: Consider cardiac MRI, evaluate for infiltrative disease

Step 5: Identify Hyperdynamic Causes

• Check hemoglobin, thyroid function
• Assess volume status
• Review medications (vasodilators, inotropes)

When to Worry vs. Reassure

Reassuring features:

• No structural abnormalities
• Normal diastolic function
• Normal GLS
• Identifiable benign cause (athletic heart, mild anemia)

Concerning features requiring further workup:

• LV hypertrophy (especially asymmetric)
• Abnormal diastolic parameters
• Reduced GLS despite high EF
• Left atrial enlargement
• Family history of cardiomyopathy or sudden death

Common Pitfalls

1. Assuming high EF = normal cardiac function: Patients with HCM can have EF >70% yet be at high risk for sudden death and heart failure 3

2. Ignoring diastolic dysfunction: Heart failure with preserved EF (HFpEF) carries significant morbidity and mortality 4

3. Not measuring GLS in preserved EF: This is the most sensitive marker of early systolic dysfunction in cardiomyopathies 3

4. Overlooking LVOT obstruction in HCM: Can be dynamic and provoked by exercise or Valsalva 3

Bottom Line

In an asymptomatic adult, a high ejection fraction alone is not concerning and usually represents normal cardiac function. However, it should prompt a comprehensive echocardiographic evaluation including structural assessment, diastolic function, and consideration of GLS measurement to exclude underlying cardiomyopathies that may present with preserved or hyperdynamic systolic function but carry significant prognostic implications.