Hemodynamic Calculations Flashcards
What is volume equal to?
Area x Distance
What is the stroke volume equal to?
Cross sectional area (CSA) x Stroke Distance
Where is stroke volume calculated? (2 places)
LVOT or Aortic Valve
What does the accuracy of the stroke volume determination depend on?
- Parallel Alignment of U/S beam to blood flow
- Accurate determinations of vessel cross sectional area (CSA)
How do we calculate Stroke Volume?
Stroke Volume = (Area at LVOT or Aortic Valve) x Stroke Distance
Said another way:
SV = Area x Stroke Distance = CSA x TVI
Stroke distance = TVI (Time Velocity Intergral) = VTI

How would we measure CSA of LVOT to measure stroke volume?
Deep Transgastric Long Axis view with U/S Beam through Aortic Valve
- Measure LVOT
- Use (pi)*r2

How do you calculate Stroke Distance Logistically?
- Deep TG with doppler through Aortic Valve
- Measure negative deflection
- This will give you TVI = Stroke Distance

What is Qp / Qs mean?
Qp = Flow through Right side of heart (p = pulmonary)
Qs = Flow through the Left side of the heart (s = systemic)
How do we calculate Qp/Qs on echo?
SVPA / SVLVOT
SVPA = APA x TVIPA
SVLVOT = ALVOT x TVILVOT
What TEE view do we use to calculate the Stroke Volume through the PA?
Mid-Esophageal Ascending Aorta Short Axis
What TEE view do we use to calculate Stroke Volume of the LVOT?
Mid Esophageal Long Axis to get Area of the LVOT
Deep TG Short Axis to get TVILVOT

How close do you want to measure the LVOT from the aortic valve?
Stay within 1 cm (Distance changes the further you go away from that)
What is the derivation to arrive at the Regurgitant Volume equation?
Volume in = Volume out
Diastolic LV inflow = Systolic LV outflow = (SV forward + Regurgitant Volume)
SVMV inflow = SVAV + Regurgitant VolumeMV
Regurgitant VolumeMV = SVAV - SVMV inflow
How do you calculate SVMV?
AMV x TVIMV
What is the cutoff for Mild MR based on Regurgitant Volume?
<30 mL
What is the cutoff for Moderate MR based on Regurgitant Volume?
30 - 59 mL
What is the cutoff for Severe MR based on Regurgitant Volume?
> 60 mL
What is the formula for regurgitant volume?
SVMV - SVLVOT
SV<strong>MV</strong> = AMV x TVI MV inflow
SVLVOT = ALVOT x TVILVOT
What are all the ways that the Area of the Mitral valve can be calculated in order to obtain SVMV?
220 / Pressure Half Time
760 / Decelaration TIme
PISA
Continuity Equation
Pi * r2
What is the regurgitant fraction?
What is the equation for this?
Backwards Flow / Total Flow
Regurgitant Fraction (RF) = Regurgitant Volume / SVMV Inflow
What is the cutoff for Mild MR based on Regurgitant Fraction?
<30%
What is the cutoff for Moderate MR based on Regurgitant Fraction?
30-49%
What is the cutoff for Severe MR based on Regurgitant Fraction?
>50%
What is the regurgitant orifice area?
Area of the hole through which regurgitation occurs
regurgitant orifice area equation
Volume = Area x Distance
Regurgitant Orifice Area = Regurgitant Volume / TVI Mitral Valve
What is the cutoff for Mild MR based on Regurgitant Orifice Area?
< 0.2 cm2
What is the cutoff for Moderate MR based on Regurgitant Orifice Area?
0.2 - 0.39 cm2
What is the cutoff for Severe MR based on Regurgitant Orifice Area?
> 0.4 cm2
What do we use to calculate intracardiac pressures?
Change in Pressure (Delta) = 4V2
How do you estimate RA pressure?
IVC size
What is the estimated Right Atrial Pressure for an IVC of <1.5 cm and Collapses with Sniff?
0 - 5 mmHg
What is the estimated Right Atrial Pressure for an IVC of 1.5-2.5 cm and Decreases >50%?
5 - 10 mmHg
What is the estimated Right Atrial Pressure for an IVC of 1.5-2.5 cm and Decreases <50%?
10 - 15 mmHg
What is the estimated Right Atrial Pressure for an IVC of >2.5 cm and Decreases <50%?
15 - 20 mmHg
What is the estimated Right Atrial Pressure for an IVC of >2.5 cm and No change with Sniff?
>20 mmHg
What is the RV Diastolic Pressure going to equal?
RVDP = RAP
*Unless Tricuspid Stenosis is present
To calculate RVSP, What view do we use?
Mid-esophageal 4 chamber with U/S beam through tricuspid valve
What is the equation for RVSP?
Change in Pressure = 4*V2
RVSP - RAP = 4 (Velocity of Max TR Jet)2
*Rearrange equation*
RVSP = 4 (Velocity of Max TR Jet)2 + RAP
What is the equation for Pulmonary Artery Systolic Pressure?
*What is the caveat*
PASP = RVSP - Change in Pressure (Pulmonic Stenosis)
*Caveat is Pulmonic Stenosis in which you have to subtract the gradient across the pulmonic valve
How do we calculate the Main Pulmonary Artery Mean Pressures?
Not done often**
Change in P = 4 V2
PAMP - RVDP = 4 (VPI early)2
PAMP = 4 (VPI early)2 + RVDP
PAMP = 4 (VPI early)2 + RAP

When do you use VPI early and when do you use VPI late?
Early = PA Mean
PAMP = 4 (VPI Early)2 + RAP
Late = PA Diastolic
PADP = 4 (VPI Late)2 + RAP

How do we estimate Left Atrial Pressure?
Equation
Measure this from the velocity of an MR Jet
Change in Pressure = 4 V2
LVSP - LAP = 4 (VMR)2
*LVSP can be substituted by SBP*
LAP = SBP - 4 (VMR)2

If you have a VSD, How do you calculate RVSP?
Change in Pressure = 4V2
LVSP - RVSP = 4 (VVSD)2
RVSP = LVSP - 4 (VVSD)2

What is Dp/Dt?
Isovolumetric rate of LV Pressure rise
Said another way:
Rate of LV pressure rise during isovolumetric contraction of the LV
What is Dp/Dt calculated as?
Slope of LV Pressure rise from 4-36 mmHg (VMR = 1 to VMR = 3 m/s)
What is Dp/Dt dependent on?
Preload
What is Dp/Dt independent of?
Afterload
What is the equation for calculating Dp/Dt?
Use Change in Pressure = 4V2
With Mitral Regurgitation: Change in P = (PLV - PLA) = 4 (VMR)2
PLV = 4 (VMR)2 + PLA
Then substitute
VMR 1 = 4 so PLV = 4 + PLA
VMR 3 = 36 so PLV = 36 + PLA
Change in P / Change in T = 32/ Change in T

What is the Dp/Dt for this picture?
Change in Time is 0.06

Change in P = 32 / 0.06
533 mmHg
The peak velocity is 280 cm/sec
Given BP of 120/80, Calculate RVSP

- Convert 280 cm/sec = 2.8 m/sec
- Realize its a VSD
- RVSP = LVSP - 4 (VVSD)2
- RVSP = 120 - 31 = 88 mmHg
What Tricuspid Valve Leaflets are seen here?

Left = Septal / Posterior
Right = Anterior

What is the green circle at?

Right Atrial Appendage
What pressure can be calculated from this?
This is the Tricuspid valve shown here with an U/S beam through it.
You can calculate:
RVSP using Bernoulli (Change in Pressure) = 4 * (VTR JET)2 + RAP

RV Systolic Pressure = Pulmonary Systolic Pressure in the absence of what?
Pulmonic Stenosis
What TR peak velocity is indicative of elevated Left Atrial Pressure?
What TR peak velocity is indicative of elevated Diastolic Dysfunction?
>2.8 m/sec
*Commit to memory*
What is normal Mitral E/A ratio?
>/= 0.8
What is impaired Grade 1 Diastolic Dysfunction for Mitral E/A ratio?
= 0.8
What is impaired Grade 2 Diastolic Dysfunction Mitral E/A ratio?
>0.8 and <2
What is impaired Grade 3 Diastolic Dysfunction for Mitral E/A ratio?
>2
What the average E/e’ ratio for normal diastolic function?
<10
What the E/e’ ratio for Grade 1 diastolic function?
<10
What the E/e’ ratio for Grade 2 diastolic function?
10-14
What the E/e’ ratio for Grade 3 diastolic function?
>14
What the Peak TR V (m/sec) for normal diastolic function?
<2.8 m/sec
What the Peak TR V (m/sec) for Grade 1 diastolic function?
< 2.8 m/sec
What the Peak TR V (m/sec) for Grade 2 diastolic function?
>2.8 m/sec
What the Peak TR V (m/sec) for Grade 3 diastolic function?
> 2.8 m/sec
What is the LA volume index for normal diastolic function?
< 34 mL/m2
What is the LA volume index for Grade I diastolic dysfunction?
“NI” or increased
What is the LA volume index for Grade 2 diastolic dysfunction?
> 34 mL/m2
What is the LA volume index for Grade 3 diastolic dysfunction?
>34 mL/m2
In patients with a normal Ejection fraction, what are the 4 determinants that factor into diastolic dysfunction diagnosis?
- Average E/e’ >14
- Septal e’ < 7 cm/sec or Late e’ <10 cm/sec
- TR Velocity >2.8 m/sec
- LA volume index > 34 mL/m2
What is the criteria for determining Normal Diastolic Dysfunction for patients with normal LVEF?
<50% positive
- Average E/e’ >14
- Septal e’ < 7 cm/sec or Late e’ <10 cm/sec
- TR Velocity >2.8 m/sec
- LA volume index > 34 mL/m2
What is the criteria for intermediate determination for diastolic dysfunction for patients with normal LVEF?
50% positive
- Average E/e’ >14
- Septal e’ < 7 cm/sec or Late e’ <10 cm/sec
- TR Velocity >2.8 m/sec
- LA volume index > 34 mL/m2
What is the criteria for determining diastolic dysfunction for patients with normal LVEF?
>50% positive
- Average E/e’ >14
- Septal e’ < 7 cm/sec or Late e’ <10 cm/sec
- TR Velocity >2.8 m/sec
- LA volume index > 34 mL/m2
What are the criteria for a one step determination for Grade 1 Diastolic Dysfunction?
E/A = 0.8
AND
E = 50 cm/sec
What are the criteria for a one step determination for Grade 3 Diastolic Dysfunction?
E/A >/= 2
What E/A and E criteria are required to find more information before determining diastolic dysfunction criteria?
E/A = 0.8 and E > 50 cm/sec
OR
E/A >0.8 but <2
If you have:
E/A = 0.8 and E > 50 cm/sec
OR
E/A >0.8 but <2
What additional 3 criteria need to be evaluated?
- Average E/e’ >14
- TR velocity > 2.8 m/sec
- LA Volume Index >34 mL/m2
What is the pathway for determining criteria for Grade 1 diastolic function, Grade II Diastolic function or indeterminate?
- Average E/e’ >14
- TR velocity > 2.8 m/sec
- LA Volume Index >34 mL/m2
If 2 of above negative = Grade 1 Diastolic Dysfunction
If 1 positive, 1 negative = Cannot determine LAP and Diastolic Dysfunction
If 2 positive = Grade II Diastolic Dysfunction
See image for question

6.8 L/min

What valve is this?
What is the Peak instantaneous pressure across the valve if the V-peak = 100 cm/sec

Pulmonic valve
4 mmHg

What is the Mean pressure change in mild mitral stenosis?
<5 mmHg
What is the Mean pressure change in moderate mitral stenosis?
5 - 10 mmhg
What is the Mean pressure change in severe mitral stenosis?
>10 mmHg
What is the normal PHT for the mitral valve?
30 - 89 msec
What is the PHT for mild mitral stenosis?
90 - 150 msec
What is the PHT for moderate mitral stenosis?
150 - 219 msec
What is the PHT for severe mitral stenosis?
>220 msec
What is the normal Mitral valve Area?
>2.5 cm2
What is the Mitral Valve area in mild mitral stenosis?
1.6 - 2.5 cm2
What is the Mitral Valve area in moderate mitral stenosis?
1.0 - 1.5 cm2
What is the Mitral Valve area in severe mitral stenosis?
<1.0 cm2
What is the formula for Mitral valve area if you are given the PHT?
MVA = 220 / PHT
What equation relates the Left Atrial Pressure, Right atrial pressure and VPFO?
LAP - RAP = 4 (VPFO)2
What is Epstein Anomaly associated with?
- WPW (SVT)
- Secundum ASD
What is the normal values of:
- Ejection Fraction?
- Fractional Area Contraction?
- Fractional Shortening?
EF > FAC > FS
EF = >55%
FAC = >36% (36-64%
FS = >25%
What is the formula for velocity of circumferential shortening?
VcF = FS* / *ET = [(EDD - ESD) / EDD] * ET
ET = Ejection Time
FS = Fractional Shortening
What is the Mitral Valve Area equation using Pressure Half Time?
MVA = 220 / PHT
What is the LVSP equal to?
SBP + Aortic valve gradient
If you have a Systolic BP of 120 and a peak velocity across the aortic valve of 0.5 m/s, what other information is needed to calculate LAP?
Peak velocity of MR Jet
Change in Pressure = (LVSP - LAP) = 4 (VMR)2

If given PFO velocity of 78 m/s, CVP of 14, what is the LAP?
LAP = 11.6 mmHg

If given VSD peak velocities and the Blood Pressure. What is the RVSP?
Change in P = LVSP - RVSP = 4 (VVSD)2
LVSP = Aortic Blood Pressure (Systolic)
If you have a VSD as a sequelae from an MI, what do you need to be cautious of on induction?
Oxygen and Hyperventilation
- Oxygen lowers PVR and can increase pulmonary blood flow
- Increase left to right shunting
- Decrease systemic blood flow and decrease systemic C.O.
- Worsening heart failure
As soon as ETT is in, turn down to room air
Given VSD peak velocity of 3.73 m/sec and a BP of 110/80
What is the RVSP?

Delta P = 4 V2
Delta P = LVSP - RVSP = 4 (VVSD)2
RVSP = LVSP - 4 (VVSD)2
RVSP = 110 - 4(3.73)2 = 110 mmHg - 56 = 54 mmHg
LVSP = SBP (In absence of aortic stenosis)
If you have a VSD as a sequelae from an MI, what monitors are especially important to have?
SvO2 = Pulmonary artery catheter
You have a VSD patient with a PA Catheter in the ICU you have hypotension in setting of increased SvO2 from 70-99, what is the diagnosis until proven otherwise?
VSD patch has ruptured
What are the parameters you need to measure Qp (Flow through the pulmonary circuit?
Ascending Aorta Short Axis to get:
- PA diameter
- VTI through RVOT

What is seen in the coronary sinus with severe TR?
Systolic Flow reversal in the coronary sinus
What is seen in the Hepatic Veins here?

Pulsed-wave Doppler of the hepatic veins demonstrating systolic flow reversal.
ASV wave in ASVD wave are merged
What is the Peak velocity with severe TR?
Gradient actually similar between atria
Paradoxical
What is TR jet vena contracta with severe TR?
>7 mm
label these waves

A wave - a result of retrograde atrial systolic flow. It is seen below the baseline as blood flow is away from the transducer.
S wave - a result of antegrade ventricular systolic flow. It is seen above the baseline as blood flow is towards the transducer.
V wave - a result of retrograde end-ventricular systolic flow. It is seen below the baseline as blood flow is away from the transducer.
D wave - a result of antegrade ventricular diastolic flow. It is seen above the baseline as blood flow is towards the transducer.

What is the formula for EF?
(EDV - ESV) / EDV
What is the formula for stroke volume?
EDV - ESV
What is the formula for velocity ratio when doing aortic valve calculations?
AreaAV / AreaLVOT = VelocityLVOT / VelocityAV
What is the defintion of aortic sclerosis that does not meet mild AS (normal) on aortic jet velocity?
< 2.5 m/s
Aortic Jet Velocity:
Mild AS
2.6 - 2.9 m/s
Aortic Jet Velocity:
Moderate AS
3 - 4 m/s
Aortic Jet Velocity:
Severe AS
>4 m/s
Mean Gradient per American Guidelines
Mild AS
<20 mmHg
Mean Gradient per American Guidelines
Moderate AS
20 - 40 mmHg
Mean Gradient per American Guidelines
Severe AS
>40 mmHg
AVA by continuity equation for:
Mild AS
>1.5 cm2
AVA by continuity equation for:
Moderate AS
1.0 - 1.5 cm2
AVA by continuity equation for:
Severe AS
<1.0 cm2
Indexed AVA
Mild AS
>0.85 cm2/m2
Indexed AVA
Moderate AS
0.6 - 0.85 cm2/m2
Indexed AVA
Severe AS
<0.6 cm2/m2
Velocity Ratio
Mild AS
>0.5
Velocity Ratio
Moderate AS
0.25 - 0.5
Velocity Ratio
Severe AS
< 0.25
What can be caculated from Peak Early Velocity of the aortic valve?
Mean PAP
**Check this answer with an attending**
What can be caculated from Peak Late Velocity of the aortic valve?
LVEDP
Given a BP of 100/55, what is the LVEDP when you have a peak late velocity of 3.38 m/sec?
Change in Pressure = 4V2 = AoDP - LVEDP
4 (VAI LATE) = 4(3.38)2
LVEDP = 55mmHg - 45.7 mmHg
LVEDP = 9.3 mmHg

What is helpful when using the dimensionless index (velocity ratio) for BMI considerations?
Size independent
What is the difference of LVOT area in 2d (ME AV LAX) vs. 3d?
2D = Underestimates LVOT area = Overestimate the degree of stenosis
2D = D1 but this is more of an ellipse

This card marks questions on the practice exam (No question)
This card marks questions on the practice exam (No answer)