Cardiovascular Doppler Echocardiography: Maximum Velocity of E-Wave (Eprime) and Diastolic Index Ratio (E′/E)
This test measures the ratio of your heart’s diastolic function using Doppler ultrasound. It helps assess how well your heart relaxes and fills with blood between beats.
["A key tool for evaluating heart valve and chamber function, often used alongside other echocardiogram measurements."]
Key facts at a glance
- LOINC
- 81386-5
- Short code
- MV E-wave Vmax/e-prime Vmax DOP+TDI
- Synonyms
- MV E-wave Vmax/e-prime Vmax DOP+TDI
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- us-doppler-tissue-doppler
- CPT
- 85610
- SNOMED
- 396252006
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test evaluates two primary measurements: the maximum velocity of the mitral valve’s early diastolic flow (E-wave) and the tissue Doppler-derived early diastolic velocity of the mitral annulus (E′). The ratio (E′/E) helps determine how efficiently your heart relaxes during diastole, which is critical for proper blood flow and cardiac function.
How the Test Works
During the procedure, a small ultrasound probe is placed on your chest. The probe emits sound waves that bounce off your heart’s structures, capturing real-time images and measurements of blood flow and tissue movement. The E-wave measures the speed of blood flowing backward into the left atrium during early relaxation, while E′ measures the movement of the heart muscle itself.
Why It’s Done
Your healthcare provider may order this test to diagnose or monitor conditions affecting heart relaxation, such as diastolic heart failure, mitral valve disorders, or other cardiac dysfunctions. It’s often used alongside other echocardiogram findings to get a full picture of your heart’s performance.
Common Conditions Evaluated
This ratio helps identify whether your heart is filling too slowly (indicative of restrictive physiology) or if there’s abnormal stiffness in the heart muscle, which can lead to symptoms like shortness of breath, fatigue, or fluid retention.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A lower E′/E ratio (typically >1.5) often suggests diastolic dysfunction, where the heart doesn’t relax properly, leading to reduced filling capacity. Higher ratios may indicate normal or less restrictive filling. This test is particularly useful in patients with symptoms of heart failure without obvious systolic dysfunction (e.g., preserved ejection fraction).
Short name
E′/E Ratio (Eprime-to-E-wave Velocity Ratio)
Frequently asked questions
What does an abnormal E′/E ratio mean?
How often is this test repeated?
Is this test painful?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy