Surgical aortic prosthesis · obstruction calculator
Explore surgical aortic prosthesis · obstruction with the method’s inputs, acquisition guidance and source references. Open the calculator to enter measurements or try an illustrative worked example.
Method
2024 ASE Table 5 · pair flow-dependent and flow-independent SAVR findings
Use the measurement units shown below. Some fields apply only to a selected method or condition; follow the interactive tool’s method choices. The interactive tool keeps missing measurements incomplete and provides its method-specific results and reference context.
Measurements and acquisition
Peak velocity m/s
Continuous-wave Doppler
- Align the CW cursor as parallel as possible to the jet.
- Acquire a dense, complete envelope without truncation.
- Measure the highest absolute velocity on the selected envelope.
Mean gradient mmHg
Complete traced CW envelope
- Align through the valve or shunt and record a complete envelope.
- Trace the modal velocity envelope using the machine tool.
- Use the machine-calculated mean gradient in mmHg.
DVI · LVOT VTI ÷ prosthesis VTI
Enter the measured value in the displayed unit
- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.
EOA vs expected valve reference
Enter the measured value in the displayed unit
- Not available
- Within 1 SD
- 1 to <2 SD below
- ≥2 SD below
- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.
Acceleration time ms
Spectral Doppler timing
- Use a sweep speed that clearly shows the interval boundaries.
- Measure from the specified onset to offset.
- Average representative beats using consistent rhythm handling.
AT/ET ratio
Spectral Doppler timing
- Use a sweep speed that clearly shows the interval boundaries.
- Measure from the specified onset to offset.
- Average representative beats using consistent rhythm handling.
Sources and method context
American Society of Echocardiography · 2024 · Guidelines for the Evaluation of Prosthetic Valve Function With Cardiovascular Imaging · Figure 13 and Table 5 · JASE p. 19 · recommendations p. 21
- SAVR obstruction ranges · Table 5 · JASE p. 19
Peak velocity, mean gradient, DVI, reference-relative EOA, acceleration time, and AT/ET ranges.
- Required parameter concordance · Table 5 footnote · JASE p. 19
Significant stenosis should include at least one flow-dependent and one flow-independent parameter.
- Acquisition and differential · Key recommendations · PDF p. 21
Multiple Doppler windows and exclusion of high flow, PPM, sub/supravalvular obstruction, and pressure recovery.
Catalogue review status: Exact guideline locator mapped · clinical sign-off pending
These pages describe the educational tool. Interpret measurements with the complete clinical context and the method’s acquisition limitations.