Canonical: https://echosuite.app/guides/coarctation/

# Coarctation · anatomy & gradients calculator

Explore coarctation · anatomy & gradients with the method’s inputs, acquisition guidance and source references. Open the calculator to enter measurements or try an illustrative worked example.

Created by [Mohammed Kamareddine, MD](https://echosuite.app/about/) · [Sources & educational scope](https://echosuite.app/about/)

[Open interactive calculator →](https://echosuite.app/calculators/#coarctation)

## Method

Peak ΔP = 4V₂²; corrected peak ΔP = 4(V₂² − V₁²); mean from systolic CW trace

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

### Available measurement

Enter the measured value in the displayed unit

- Corrected peak
- Peak only
- Traced mean
- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.

### Proximal peak velocity V₁  m/s

Pulsed-wave Doppler

- Position the PW sample gate at the required anatomical station.
- Align with flow and save a complete, unaliased envelope.
- Measure the reproducible dense peak from zero in velocity units, not VTI.

### Coarctation peak velocity V₂  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.

### Traced systolic 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.

## Sources and method context

ACC / AHA / HRS / ISACHD / SCAI · ASE / EACVI · 2025 · 2025 Guideline for the Management of Adults With Congenital Heart Disease · Coarctation section · Table 25 and footnotes · doi:10.1016/j.jacc.2025.09.006

[Primary reference](https://doi.org/10.1016/j.jacc.2025.09.006)

- Adult significance, not a severity scale · 2025 ACHD guideline · Table 25

Mean Doppler and corrected maximum instantaneous gradients >20 mmHg are suggestive features; interpret lower gradients cautiously with LV dysfunction, severe AS or collaterals and elevated gradients after repair.

- Acquisition and downstream flow · ASE / EACVI Thoracic Aorta 2015 · pp. 162–163, Figure 51 · doi:10.1016/j.echo.2014.11.015

Suprasternal arch imaging and Doppler, delayed abdominal systolic upstroke and persistent forward diastolic flow; multimodality assessment of the whole aorta.

- Doppler versus catheter gradients · Egbe et al. 2023 · PMID 37660667 · PMC10805228

Only modest echo–catheter correlations in 121 adults. Peak, corrected peak and mean are distinct measurements; no regression conversion is implemented.

- Reporting anatomy and associated disease · ASE adult echo reporting 2025 · congenital lesions table · doi:10.1016/j.echo.2025.06.001

Describe narrowing, branch relationship, arch dimensions, diastolic continuation, abdominal Doppler and residual aortic complications.

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.

## Keep exploring

- [Qp/Qs calculator: pulmonary to systemic flow ratio](https://echosuite.app/guides/qpqs/)
- [Atrial septal defect: shunt and Doppler calculator](https://echosuite.app/guides/asd/)
- [VSD · size & right-heart pressure calculator](https://echosuite.app/guides/vsd-pressure/)
- [PDA · shunt & PA pressure calculator](https://echosuite.app/guides/pda-pressure/)

[All echo guides](https://echosuite.app/guides/) · [Learning paths](https://echosuite.app/learn/)