Mean pulmonary artery pressure calculator: RVOT acceleration time
Find the RVOT acceleration-time method for mean pulmonary artery pressure, with its acquisition guidance and reference context.
Method
mPAP = 79 − 0.45 × RVOT AcT; if AcT <120 ms, also 90 − 0.62 × AcT
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
RVOT acceleration time ms
PW Doppler just below the pulmonary valve
- From the PA-bifurcation PSAX view, place a 1–2 mm PW sample in the distal RVOT just beneath the pulmonary valve.
- Optimize scale, baseline, wall filter, and beam alignment so the entire systolic envelope is visible.
- Trace the modal envelope for VTI; measure acceleration time from flow onset to peak velocity and interpret cautiously when heart rate is <60 or >100 bpm.
Heart rate bpm
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 · 2025 · Guidelines for the Echocardiographic Assessment of the Right Heart in Adults and Special Considerations in Pulmonary Hypertension · Table 1 JASE p. 145 · RVOT AcT pp. 158–159 · Table 4 / mPAP p. 166
- Acquisition and heart-rate limitation · RVOT VTI and AcT · JASE pp. 158–159
Distal RVOT sample placement, onset-to-peak timing, >105-ms normal reference, and reduced reliability below 60 or above 100 bpm.
- Empirical equations · Table 4 · JASE pp. 161–163; mPAP p. 166
The 79−0.45×AccT equation and the alternate 90−0.62×AccT equation when AccT is below 120 ms.
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.
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