Echo calculators
Worked steps on every result, unit-safe inputs (pick mm or cm — no silent errors), and shared values like LVOT diameter and BSA entered once and reused across every calculator. 17 live and growing. Free to use.
Valves — stenosis
Continuity equation — AVA (VTI method)
AVA and AVA index from LVOT diameter, LVOT VTI and AV VTI, with worked steps.
Continuity equation — AVA (peak-velocity method)
AVA from LVOT diameter and peak velocities (Vmax) instead of VTIs.
Aortic peak & mean gradient (Bernoulli)
Peak (and modified) pressure gradient across the aortic valve from Vmax.
Mitral valve area — pressure half-time
MVA in mitral stenosis by the empirical 220/PHT method.
Dimensionless index (DVI) — aortic
SoonVTI ratio to grade aortic stenosis independent of LVOT diameter.
Mitral valve area — continuity & PISA
SoonMVA in mitral stenosis by the continuity and PISA methods.
Pulmonary / tricuspid stenosis gradient
SoonPeak and mean gradients across stenotic pulmonary or tricuspid valves.
Aortic valve resistance
SoonValvular resistance as an adjunct in low-flow aortic stenosis.
Energy loss index
SoonAS severity corrected for pressure recovery in the ascending aorta.
Prosthetic valve DVI & EOA
SoonDimensionless index and effective orifice area for prosthetic valves.
Wilkins valvuloplasty score
SoonMitral morphology score predicting balloon valvuloplasty suitability.
Valves — regurgitation
PISA — mitral regurgitation
EROA, regurgitant volume and fraction from the PISA radius.
Aortic regurgitation — pressure half-time
SoonAR severity from the diastolic pressure half-time of the regurgitant jet.
Regurgitant volume & fraction (volumetric)
SoonVolumetric regurgitant volume and fraction from two stroke volumes.
PISA — tricuspid regurgitation
SoonEROA and regurgitant volume for TR from the PISA radius.
Pulmonary regurgitation severity
SoonGrade pulmonary regurgitation from jet and pressure-half-time measures.
Vena contracta width
SoonRegurgitation severity from the vena contracta width.
Chambers & function
LV ejection fraction — Simpson's biplane
EF and stroke volume from biplane end-diastolic and end-systolic volumes.
LV ejection fraction — Teichholz
EF from linear LV internal dimensions (Teichholz) — with its caveats noted.
LV mass & mass index
ASE cube-formula LV mass and BSA-indexed mass with hypertrophy thresholds.
LA volume & LA volume index
LA volume (biplane area-length) and BSA-indexed LAVi with thresholds.
RV fractional area change
SoonRV systolic function from end-diastolic and end-systolic areas.
LV EF — Quinones / Dumesnil
SoonEF from linear dimensions by the Quinones and Dumesnil methods.
Tei index (myocardial performance)
SoonGlobal myocardial performance index for LV and RV.
dP/dt (LV & RV contractility)
SoonRate of pressure rise from the MR (or TR) CW Doppler trace.
Fractional shortening
SoonLV fractional shortening from end-diastolic and end-systolic dimensions.
Relative wall thickness
SoonRWT to classify concentric vs eccentric LV remodelling.
MAPSE / TAPSE interpreter
SoonLongitudinal function from mitral/tricuspid annular plane excursion.
LV sphericity index
SoonLV remodelling from the long-axis to short-axis ratio.
Aortic root & sinus index
SoonAortic root dimensions indexed to BSA.
Pressures
Pulmonary artery systolic pressure (PASP)
PASP from TR peak velocity and IVC-derived right atrial pressure.
Right atrial pressure from IVC
RAP estimate from IVC diameter and collapsibility (3/8/15 mmHg).
PCWP / LAP via E/e′ (Nagueh)
Left atrial pressure estimate from the E/e′ ratio (Nagueh regression).
LV filling-pressure algorithm (ASE 2016)
Steps through the ASE 2016 diastolic algorithm to grade filling pressure.
PA diastolic pressure
SoonPA diastolic pressure from the end-diastolic pulmonary regurgitation velocity.
Mean PA pressure
SoonMean PA pressure from the early-diastolic PR velocity or from PASP.
Pulmonary vascular resistance (Abbas)
SoonNon-invasive PVR estimate by the Abbas equation (TR Vmax / RVOT VTI).
LVEDP from AR end-diastolic gradient
SoonEstimate LV end-diastolic pressure from the AR jet and diastolic BP.
Volumes & output
Doppler physics
Bernoulli equation (simplified / modified / full)
Convert Doppler velocity to a pressure gradient, all three forms.
Nyquist limit / PRF
SoonRelate pulse repetition frequency, depth and the aliasing velocity.
Doppler shift equation
SoonFrequency shift from velocity, insonation angle and transmit frequency.
Wavelength & axial resolution
SoonWavelength from frequency and the resulting axial resolution.
Cross-sectional area helper
SoonCircular cross-sectional area from a diameter.
General
Body surface area (BSA)
BSA from height and weight — feeds every indexed measurement.
Body mass index (BMI)
SoonBMI from height and weight.
Maximum predicted heart rate
SoonAge-predicted maximum heart rate for stress echo targets.
METs & VO₂ (treadmill)
SoonEstimate metabolic equivalents and VO₂ from treadmill workload.
Rate-pressure product
SoonMyocardial oxygen demand index from heart rate and systolic BP.
More specialties coming
ECG
Coming soon: intervals, axis, rate.
Risk scores
Coming soon: CHA₂DS₂-VASc, HAS-BLED and more.
Haemodynamics
Coming soon: shunts, resistance, cardiac output.