1. What is Doppler Velocity Index (DVI)?

The Doppler Velocity Index (DVI) is a dimensionless ratio used in echocardiography to assess the severity of aortic stenosis. It compares the velocity-time integral (VTI) of the left ventricular outflow tract (LVOT) to the VTI of the aortic valve (AV).

2. How Does the Calculator Work?

The calculator uses the DVI formula:

Where:

• \( LVOT\ VTI \) — Velocity-time integral of the left ventricular outflow tract (cm)
• \( AV\ VTI \) — Velocity-time integral of the aortic valve (cm)

Explanation: The DVI provides a ratio that helps evaluate the severity of aortic valve stenosis independent of the LVOT diameter measurement.

3. Importance of DVI Calculation

Details: DVI is particularly useful when accurate measurement of LVOT diameter is challenging. A DVI value less than 0.25 typically indicates severe aortic stenosis.

4. Using the Calculator

Tips: Enter both LVOT VTI and AV VTI values in centimeters. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal DVI value?
A: In normal aortic valves, DVI is typically close to 1.0. Values decrease as aortic stenosis becomes more severe.

Q2: When is DVI particularly useful?
A: DVI is especially valuable when LVOT diameter measurement is difficult or unreliable, or in cases of suboptimal echocardiographic windows.

Q3: How does DVI relate to aortic valve area?
A: DVI is inversely related to the severity of aortic stenosis. Lower DVI values indicate more severe stenosis, similar to smaller aortic valve areas.

Q4: What are the limitations of DVI?
A: DVI may be less accurate in cases of concomitant aortic regurgitation or when there are significant errors in VTI measurements.

Q5: Can DVI be used for other valves?
A: While the concept can be applied to other valves, DVI is primarily used and validated for assessment of aortic stenosis.