Aortic Valve Velocity Ratio	LV EF (Modified Quinones Equation)	Myocardial Performance Index (RV)
AVA (Continuity Equation VTI)	LV EF (Simplified Quinones Equation)	PCWP by E/Ea (Nagueh Formula)
AVA (Continuity Equation V_Max)	LV Fractional Shortening	PISA (Mitral regurgitation)
dP/dt (LV contractility)	LV Mass and LV Mass Index	PISA (Mitral stenosis)
dP/dt (RV contractility)	Mitral valve area (PHT)	Qp/Qs
Left atrial pressure (MR)	Mitral Valvuloplasty Score (MGH)	RVSP (TR)
LA Volume (Biplane Method)	Modified Bernoulli Equation	Stroke Volume, Cardiac Output
LV EF (Dumesnil Method)	Myocardial Performance Index (LV)

Pulmonary-Systemic Flow Ratio (Qp/Qs)

LVOT				mm
LVOT VTI				cm
RVOT				mm
RVOT VTI				cm

Qp/Qs

Qp/Qs can be estimated by using 2-D echo and spectral Doppler measurements in patients who have intra- or extra-cardiac shunts e.g. atrial or ventricular septal defects.

Qp =

RVOT VTI * π *

RVOT

Qs =

LVOT VTI * π *

LVOT

Qp/Qs Ratio =

Qp/Qs

Variable	Definition
Input
LVOT	Left ventricular outflow tract diameter (mm)
LVOT VTI	RVOT subvalvular velocity time integral (cm)
RVOT	Left ventricular outflow tract diameter (mm)
RVOT VTI	RVOT subvalvular velocity time integral (cm)
Output
Qp/Qs	Pulmonary-Systemic Shunt Ratio

References

	Sanders SP, et al. Measurement of systemic and pulmonary blood flow and Qp/Qs ratio using Doppler and two-dimensional echocardiography. Am J. Cardiol, 51:952, 1983.

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Author: Dr. Chi-Ming Chow

Developer: Edward Brawer

Disclaimer: The calculators provided are not meant to be a substitute for professional advise and are not to be used for medical diagnosis. All calculations must be confirmed before clinical use or diagnostic purposes by qualified medical professionals. The authors make no claims of the accuracy of the information contained herein. The authors make no claims whatsoever, expressed or implied, about the authenticity, accuracy, reliability, completeness or timeliness of the material, software, text, graphics and links given. In no event shall the authors, its suppliers, affiliates or any third parties be liable in any manner whatsoever for any damage arising upon use of any information provided.