# Online Calculators for Echocardiography Formulas

## Perform online calculations for a variety of echocardiographic and Doppler formulas

February 14th, 2022

(updated April 14th, 2022)

The Calculator has been devised to facilitate the daily diagnostic work with your ultrasound unit.

The page connects to Microsoft OneDrive and a stable internet connection is necessary.

Fill the yellow fields on the left – calculations are shown in the gray fields on the right.

Formulas being used are described here, and Abbreviations here.

**Content**:

- BSA
- 2D LV Stroke Volume and index
- 2D Cardiac Output
- Doppler RV Stroke Volume and index
- Qp / Qs
- Pulmonary Diastolic and Systolic Pressures
- Pulmonary Vascular Resistances
- Aortic valve area (Continuity Eq.)

- Doppler PISA method

– Aortic EROA, Regurgitant Volume & Fraction

– MItral EROA, Regurgitant Volume & Fraction - MItral annulus biplane area
- Aortic and Mitral Doppler stroke volumes
- Doppler Stroke Volume Method:

– Aortic EROA, Regurgitant Volume & Fraction

– Mitral EROA, Regurgitant Volume & Fraction - Pericardial Effusion Volume

## Abbreviations

- AV – Aortic valve
- BSA – Body Surface Area
- CW – Continuous Wave Doppler
- EROA – Effective Regurgitant Orifice Area
- EDV – End diastolic volume
- ESV – End systolic volume
- Grad. – Gradient
- LV – Left ventricle
- LVCO – LV cardiac output
- LVEDV – LV end-diastolic volume
- LVEDVi – LVEDV index
- LVESV – LV end-systolic volume
- LVESVi – LVESV index
- LVOT – LV outflow tract
- LVSV – LV stroke volume
- LVSVi – LVSV index
- MV – Mitral valve

- PD – Pulsed Doppler
- PISA – Proximal Isovelocity Surface Area
- PR – Pulmonary regurgitation
- PDP – Pulmonary diastolic pressure
- PSP – Pulmonary systolic pressure
- PVR – Pulmonary vascular resistances
- Qp/Qs – ratio of RV and LV stroke volumes
- RAP – Right atrial pressure
- Regurg. – Regurgitant
- RV – Right ventricle
- RVOT – RV outflow tract
- RVSV – RV stroke volume
- RVSVi – RVSV index
- TR – Tricuspid regurgitation
- Vel. – Velocity
- Vmax – Maximum velocity
- VTI – Velocity-Time integral

## Formulas

**Body Surface Area**

The BSA is used to index (divide by BSA): volumes, stroke volumes, aortic valve area.

The following formula is used=*0.007184 x (weight)^0.425 x (Height)^0.725*

**LV Volumes**

Biplane volumes are averaged from 4-chamber and 2-chamber volumes. Ejection fraction is calculated as=

(end-diastolic volume – end-systolic volume) / end-diastolic volume) * 100

**Stroke Volumes**

Stroke volumes are obtained with the formula=*Velocity-time integral x area (LVOT / RVOT / Mitral valve annulus)*

**LVOT / RVOT areas**

Outflow tract areas areas are calculated as circles, from diameters

**MV annulus area**

The elliptical area is obtained with the formula=*3.14 x (intercommissural diameter / 2) x (antero-posterior diameter / 2)*

**PSP**

Pulmonary systolic pressure is calculated=*TR peak systolic gradient + estimated RAP (obtained from the collapsibility dynamics of the inferior vena cava)*

**PDP**

Pulmonary diastolic pressure is calculated= *PR end-diastolic gradient + estimated RAP (obtained from the collapsibility dynamics of the inferior vena cava)*

**PVR**

Pulmonary vascular resistances are calculated with the formula=*(TR peak systolic gradient / RVOT velocity-time integral) x 10*

**Aortic valve area**

The area is obtained with the continuity equation=*(LVOT pulsed Doppler velocity-time integral x LVOT area) / AV continuous wave systolic velocity-time integral*

**PISA calculations (valve regurgitation)**

The EROA is calculated with the formula=

(*(PISA radius^2) x 3.14 x 2) x Aliasing velocity) / Peak regurgitant velocity*

The Regurgitant Volume is calculated with the formula=*EROA x regurgitant velocity-time integral*

The Regurgitant Fraction is calculated with the formula=*(Regurgitant Volume / Valve stroke volume) x 100*

**Quantitative Doppler**

Mitral Regurgitant Volume is calculated with the formula=*Mitral valve stroke volume – LVOT stroke volume*

Mitral Regurgitant Fraction is calculated with the formula=*Mitral Regurgitant Volume / Mitral stroke volume) x 100*

MItral EROA is calculated with the formula=*Mitral Regurgitant Volume / Mitral regurgitant continuous wave velocity-time integral*

Aortic Regurgitant Volume is calculated with the formula=*LVOT stroke volume – Mitral valve stroke volume*

Aortic Regurgitant Fraction is calculated with the formula=*Aortic Regurgitant Volume / LVOT stroke volume) x 100*

Aortic EROA is calculated with the formula=*Aortic Regurgitant Volume / Aortic regurgitant continuous wave velocity-time integral*

**Pericardium**

Prolate ellipse formula=

π x 4/3 x L/2 x D1/2 x D2/2