Ejection Fraction (EF) Calculator for Reduced Ejection Fraction (HFrEF)
Example of systolic heart failure with dilated ventricle and reduced pumping efficiency (EF ≈ 27%).
Calculates the heart's Ejection Fraction (EF), which measures the percentage of blood pumped out of the left ventricle with each contraction. Enter your Stroke Volume, End-Diastolic Volume to get an instant ejection fraction (%). Formula: (stroke_volume / end_diastolic_volume) * 100.
Ejection Fraction (%)
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How It Works
How It Works
The Ejection Fraction (EF) calculator measures how efficiently your heart pumps blood with each beat. It compares the amount of blood pumped out of the left ventricle (Stroke Volume) to the total amount of blood in the ventricle before it contracts (End-Diastolic Volume).
The formula divides Stroke Volume by End-Diastolic Volume and then multiplies the result by 100 to convert it into a percentage.
- Enter Stroke Volume (mL) — the blood pumped out in one beat
- Enter End-Diastolic Volume (mL) — the total blood in the ventricle before contraction
- The calculator divides Stroke Volume by End-Diastolic Volume
- The result is multiplied by 100 to give a percentage
Understanding the Results
The result shows the percentage of blood pumped out of the left ventricle with each heartbeat. A higher percentage means the heart is pumping more efficiently, while a lower percentage may indicate reduced heart function.
This value helps doctors assess heart performance and detect possible heart conditions.
- Normal EF is typically between 55% and 70%
- Below 40% may indicate weakened heart function
- Values between 40% and 54% may suggest mild dysfunction
- Always interpret results with guidance from a healthcare professional
Frequently Asked Questions
What is Ejection Fraction (EF) and why is it important?
Ejection Fraction (EF) measures the percentage of blood pumped out of the left ventricle with each heartbeat. It is an important indicator of how well your heart is functioning. A normal EF typically ranges from 55% to 70%, and lower values may indicate heart failure or other cardiac conditions.
When should I use the Ejection Fraction calculator?
You should use this calculator if you know your Stroke Volume (SV) and End-Diastolic Volume (EDV) and want to quickly determine your EF percentage. These values are commonly obtained from echocardiograms, MRIs, or other cardiac imaging tests. The calculator helps convert those measurements into a clinically meaningful percentage.
What do Stroke Volume and End-Diastolic Volume mean?
Stroke Volume (SV) is the amount of blood pumped out of the left ventricle during one heartbeat. End-Diastolic Volume (EDV) is the total amount of blood in the left ventricle just before it contracts. EF is calculated by dividing SV by EDV and multiplying by 100.
What is considered a normal or abnormal EF result?
A normal EF is generally between 55% and 70%. An EF below 40% may indicate reduced heart function or heart failure, while values between 40% and 54% may be considered borderline. Very high EF values can also occur in certain medical conditions, so results should always be interpreted by a healthcare professional.
Can this calculator diagnose heart disease?
No, this calculator is for informational and educational purposes only. While EF is a key measurement in assessing heart function, a proper diagnosis requires clinical evaluation, imaging studies, and medical expertise. Always consult a healthcare provider for medical advice.
Can I use this calculator with values in different units?
Both Stroke Volume and End-Diastolic Volume must be entered in the same unit, typically milliliters (mL). Since EF is a percentage, the units cancel out during calculation. Using consistent units ensures an accurate result.
Disclaimer
This health calculator is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Disclaimer.