1. Valve Regurgitation Echocardiographic Calculations Rami Khouzam, MD

2. Definitions/Equations: Continuity equation: Flow (SV) = LVEDV - LVESV = A x TVI (SV:Stroke Volume, A: Area, TVI:Time Velocity Integral) Flow 1(SV) = Flow 2 (SV) A1 x TVI 1 = A2 x TVI2

3. 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.

4. Area Area =  r 2 = 3.14 r 2 (radius) = 0.785 d 2 (diameter)

5. 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)

6. Regurgitant Volume Regurgitant Volume (mL) = SV (Valve) - SV (systemic) Regurgitant Fraction Regurgitant Fraction (%) = SV (Valve) - SV (systemic) / SV (Valve)

8. 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

9. 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

10. ERO Effective Regurgitant Orifice area (cm 2 ) = Regurgitant Volume (mL) / TVI MR (cm) Effective Regurgitant Orifice area (cm 2 ) = Flow (mL/s) / V MR (cm/s)

11. 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 (cm 2 ) = RV (mL) / TVI MR (cm) = 34/120 = 0.28 cm 2 = 28 mm 2

12. 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 (cm 2 ) = RV (mL) / TVI AR (cm) = 46/188 = 0.38 cm 2 = 38 mm 2

13. Tips Inflow > Outflow : MR Inflow < Outflow : AR

14. What is SEVERE Regurgitation?

16. 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

17. Regurgitant Volume? A(MV) x TVI(MV) - A(LVOT) x TVI(LVOT) = 125.6 > 62.8 = 62 mL Inflow > Outflow: MR Answer: a

18. A patient has: d MV = 4 cm d LVOT = 2.5 cm TVI MV = 4 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

19. A(MV) x TVI(MV) - A(LVOT) x TVI(LVOT) = 50.2 < 122.6 = 72 mL Inflow < Outflow: AR Answer: c