Transcript Valve Regurgitation Echocardiographic Calculations Rami Khouzam, MD Definitions/Equations: • Continuity equation: Flow (SV) = LVEDV - LVESV = A x TVI (SV:Stroke Volume, A: Area, TVI:Time.

Valve Regurgitation
Echocardiographic Calculations
Rami Khouzam, MD
Definitions/Equations:
• Continuity equation:
Flow (SV) = LVEDV - LVESV
= A x TVI
(SV:Stroke Volume, A: Area, TVI:Time Velocity
Integral)
Flow 1(SV)
A1 x TVI 1
=
=
Flow 2 (SV)
A2 x TVI2
TVI
• Time Velocity Integral = stroke distance (cm).
The distance over which blood travels in one
cardiac cycle: the cycle velocity (cm/s) divided
by time (s). Usually represents Mean gradient.
• Different than V (Velocity): m/s or cm/s.
Usually represents Peak Instantaneous
gradient.
Area
Area =  r2
= 3.14 r2 (radius)
= 0.785
d2 (diameter)
Flow 1(SV)
=
Flow 2 (SV)
A1 x TVI 1 = A2 x TVI2
Inflow = Outflow
A(MV) x TVI(MV) = A(LVOT) x TVI(LVOT)
Regurgitant Volume
Regurgitant Volume (mL) =
SV (Valve) - SV (systemic)
Regurgitant Fraction
Regurgitant Fraction (%) =
SV (Valve) - SV (systemic) / SV (Valve)
Examples
• Mitral Regurgitation
d(MV) = 3.5 cm
d(LVOT) = 2.0 cm
TVI (MV) = 10 cm TVI (LVOT) = 20 cm
Calculate the Regurgitant Volume?
A(MV) x TVI(MV) - A(LVOT) x TVI(LVOT)
= 96 - 62
= 34 mL
• Aortic Regurgitation
d(MV) = 3.5 cm
d(LVOT) = 2.5 cm
TVI (MV) = 8 cm TVI (LVOT) = 25 cm
Calculate the Regurgitant Volume?
A(LVOT) x TVI(LVOT) - A(MV) x TVI(MV)
= 122 - 76
= 46 mL
ERO
• Effective Regurgitant Orifice area (cm2) =
Regurgitant Volume (mL) / TVI MR (cm)
• Effective Regurgitant Orifice area (cm2) =
Flow (mL/s) / V MR (cm/s)
Example
• Mitral Regurgitation
d(MV) = 3.5 cm
d(LVOT) = 2.0 cm
TVI (MV) = 10 cm TVI (LVOT) = 20 cm
TVI (MR) = 120 cm
• ERO (cm2) = RV (mL) / TVI MR (cm)
= 34/120
= 0.28 cm2
= 28 mm2
• Aortic Regurgitation
d(MV) = 3.5 cm
d(LVOT) = 2.5 cm
TVI (MV) = 8 cm TVI (LVOT) = 25 cm
TVI (AR) = 188 cm
• ERO (cm2) = RV (mL) / TVI AR (cm)
= 46/188
= 0.38 cm2
= 38 mm2
Tips
• Inflow > Outflow : MR
• Inflow < Outflow : AR
What is SEVERE Regurgitation?
MR
RV mL
> 60
ERO mm2 > 40
AR
> 60
> 30
More Examples
A 65 yo M with NYHA class II symptoms. EF 55
%.
d MV = 4 cm
d LVOT = 2 cm
TVI MV = 10 cm
TVI LVOT = 20 cm
V Ao = 1.2 m/s
• What’s next?
a) Operate for MR
b) Operate for AR
c) Observe MR
d) Observe combined AS/AR
Regurgitant Volume?
A(MV) x TVI(MV) - A(LVOT) x TVI(LVOT)
= 125.6 > 62.8
= 62 mL
Inflow > Outflow: MR
Answer: a
A patient has:
d MV = 4 cm
TVI MV = 4 cm
d LVOT = 2.5 cm
TVI LVOT = 25 cm
V Ao = 2.5
• This patient should have:
a) Absent A2
b) Opening snap
c) Quincke’s pulse
d) Large V-wave
e) Clubbing
A(MV) x TVI(MV) - A(LVOT) x TVI(LVOT)
= 50.2 < 122.6
= 72 mL
Inflow < Outflow: AR
Answer: c