Valve Area Calculator

Calculate aortic or mitral valve area using the Gorlin equation from cardiac catheterization data.

Medical Disclaimer

This calculator is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about your health. Never disregard professional medical advice or delay seeking it because of results from this tool.

Inputs

Cardiac output

L/min

Heart rate

bpm

Systolic ejection period (or DFP)

Mean pressure gradient

mmHg

Valve (0=Aortic, 1=Mitral)

Tab to move between fields

Results

Valve Area

0.79 cm²

Stenosis Grade

Transvalvular Flow222 mL/s

Peak Velocity (Bernoulli)12.65 m/s

Dimensionless Index (approx)0.23

How to Use This Calculator

Enter cardiac output (L/min), heart rate (bpm), and systolic ejection period or diastolic filling period (ms).
Set mean transvalvular pressure gradient (mmHg) and select valve type (aortic or mitral).
Review Valve Area (cm²), Stenosis Grade, Transvalvular Flow (mL/s), and Peak Velocity (m/s).
Aortic valve area < 1.0 cm² = severe stenosis; mitral valve area < 1.5 cm² = severe stenosis.

How the result changes with Cardiac output

Cardiac output	Valve Area	Stenosis Grade
1.95	0.31 cm²	3
5.57	0.88 cm²	3
9.93	1.58 cm²	1
14	2.22 cm²	0

What each input means

Cardiac output: Cardiac output measured by Fick or thermodilution.
Heart rate: Heart rate during catheterization.
Systolic ejection period (or DFP): Systolic ejection period for aortic valve; diastolic filling period for mitral valve.
Mean pressure gradient: Mean transvalvular pressure gradient from catheterization or echo.
Valve (0=Aortic, 1=Mitral): 0 for aortic valve, 1 for mitral valve. Adjusts Gorlin constant.

What each result means

Valve Area: Calculated valve orifice area. Aortic normal >2.0, mitral normal 4-6 cm².
Stenosis Grade: 0 = Normal, 1 = Mild, 2 = Moderate, 3 = Severe.
Transvalvular Flow: Volume flow rate across the valve per ejection/filling period.
Peak Velocity (Bernoulli): Estimated peak velocity from simplified Bernoulli: v = √(4×ΔP).
Dimensionless Index (approx): Rough DVI estimate. Normal >0.50, severe <0.25 for aortic.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Cardiac output = 5, Heart rate = 75, Systolic ejection period (or DFP) = 300, Mean pressure gradient = 40 = 5 input(s) provided
Calculate Valve Area
Valve Area = flowPerPeriod / (gorlinConstant * sqrt(meanGradient))
0.79 = 0.79
Calculate Stenosis Grade
3 = 3
Calculate Transvalvular Flow
Transvalvular Flow = (cardiacOutput * 1000) / (heartRate * sepSec)
222 = 222
Calculate Peak Velocity
Peak Velocity = sqrt(4 * meanGradient)
12.65 = 12.65