Is an ejection fraction (EF) of 65% normal in a female with a left ventricular internal diameter at diastole (LVIDD) of 2.5 cm?

Ejection Fraction of 65% with LVIDD of 2.5 cm in a Female Patient

An ejection fraction (EF) of 65% is normal, but a left ventricular internal diameter at diastole (LVIDD) of 2.5 cm is abnormally small and suggests a hyperdynamic left ventricle that may require further evaluation.

Normal Ejection Fraction Values

According to the American College of Cardiology/American Heart Association (ACC/AHA) guidelines, a normal ejection fraction ranges from 50% to 70% 1. More specifically:

• Normal EF: 50% to 70% (midpoint 60%)
• Hyperdynamic EF: greater than 70%
• Mild dysfunction: 40% to 49% (midpoint 45%)
• Moderate dysfunction: 30% to 39% (midpoint 35%)
• Severe dysfunction: less than 30%

The patient's EF of 65% falls within the normal range, though at the upper end of normal.

Left Ventricular Size Assessment

The LVIDD of 2.5 cm is significantly smaller than normal reference values:

• Normal LVIDD for females is approximately 4.6 ± 0.3 cm 2
• When indexed to body surface area (BSA), normal values are around 2.7 ± 0.2 cm/m² 2

Without knowing the patient's BSA, we can still determine that 2.5 cm is abnormally small, as it falls well below the normal range for adult females.

Clinical Implications

A small left ventricle with normal ejection fraction can be associated with several clinical conditions:

1. Hypovolemia: Decreased intravascular volume can lead to a smaller ventricular cavity
2. Hypertrophic cardiomyopathy: Especially if there is concentric hypertrophy
3. Restrictive cardiomyopathy: Can present with small ventricular chambers
4. Constrictive pericarditis: External constraint on ventricular filling
5. Hyperdynamic circulation: Such as in anemia, thyrotoxicosis, or pregnancy

Important Considerations

• A very high EF (>65%) has been associated with worse outcomes in some populations, particularly elderly women with acute coronary syndromes 3
• The small LVIDD may indicate that the ventricle is underfilled or that there is significant concentric remodeling

Recommended Next Steps

1. Complete echocardiographic assessment:

   • Evaluate for LV wall thickness to determine if there is hypertrophy
   • Assess diastolic function parameters
   • Measure left atrial size
   • Evaluate for pericardial abnormalities

2. Clinical correlation:

   • Check for symptoms of heart failure or reduced cardiac output
   • Evaluate volume status
   • Screen for conditions causing hyperdynamic states (anemia, thyrotoxicosis)
   • Review medication history (diuretics, beta-blockers)

3. Consider additional testing if clinically indicated:

   • Cardiac MRI for tissue characterization
   • Stress testing if ischemia is suspected
   • Laboratory tests for secondary causes

Conclusion

While the EF of 65% is within normal limits, the LVIDD of 2.5 cm is abnormally small. This combination suggests a small, possibly hyperdynamic left ventricle that warrants further evaluation to determine the underlying cause and clinical significance.