Hemodynamics Review Flashcards
Stroke volume
LVOT area * LVOT VTI
Stroke volume index
SV / BSA
AVA using continuity
LVOT VTI * LVOT area / AV VTI
MR flow / instantaneous flow rate
area x aliasing velocity
for area, use 2pir2
ERO for MR
ERO = MR flow / MR velocity
Quick ERO using PISA
Aliasing velocity 40
Assume MR velocity 500
ERO = PISA radias^2 / 2
RV for MR
ERO * MR VTI
MS by PHT
MVA = 220 / PHT
PHT
DT * 0.29
Pitfalls of PHT for MS
Bad with high LV pressures or impaired relaxation
Don’t use after balloon valvuloplasty
MS by continuity
MVA = LVOT area * LVOT VTI / MV VTI
Pitfalls of continuity for MS
AR increases LVOT VTI
MR increases MV VTI
PISA for MS
MVA = 2 * PI * r^2 * aliasing velocity / peak velocity * angle / 180
CO in aortic regurgitation
Must use MV SV, don’t use LVOT SV
AR RV
LVOT SV - Mitral SV
AR RF
RV / LVOT SV
AR EROA
RV / AR VTI
Severe AR RV
> 60
Severe AR RF
> 50
Severe AR ERO
> 0.3
Severe AR PHT
<250
>500 argues strongly against
Severe AR vena contracta
> 0.6
Severe AR abdominal aorta
holodiastolic reversal
HCM LVOT gradient
4 (LVOT velocity)^2
HCM LVOT gradient using MR velocity
Assume LA pressure = 15
LV - LA = 4 MR velocity^2
Gradient = LV - SBP
MR and MVP
Use PISA for ERO / RV
RV better
MR ERO correction for wall constraint
Divide angle by 180 degrees and multiple by incorrect ROA
Posterior MR jet
Posterior leaflet restriction
Anterior leaflet pathology
Anterior MR jet
Posterior leaflet perforation or other pathology
Cutoff for large aortic atheroma
> = 4mm into lumen
PAWP formula
4.6 + 5.27 * E velocity / flow propagation velocity
Normal propagation velocity young
> 55 cm/s
Normal propagation velocity middle aged - old
> 45 cm/s
LAP estimate
LAP = 4 + E/e’
LVEDP equation
LVEDP = DBP - 4 x end-diastolic velocity AR^2
LVSP equation
LVSP = 4v^2 + LAP
Peak to Peak aortic gradient of AS equation
P2P = LVSP - SBP
Calculating gradients / pressure across chambers
Receiving chamber pressure = originating chamber pressure + gradient
PVR equation
Change in pressure / Qp
Change in pressure across Pulm circulation = MPP - LAP
Mean pulmonary artery pressure equation
MPP = PADP + 1/3 (PASP-PADP)
RVSP in VSD
RVSP = SBP - peak systolic VSD gradient
PASP equation in PS
PASP = RVSP - peak PS gradient
LV dp/dt
dP/dt = dP / relative time interval dP = (4v2^2 - 4v1^2) RTI = time at V2 - time at V1
Mean LAP equation in MS
LAP = mean mitral gradient in diastole + early LV diastolic pressure
AVA by modified continuity equation
LVOT area * V LVOT / V AV
or LVOT area x DI
AV dimensionless index
DI = V LVOT / V AV
Mean AV gradient calculation
0.6 * peak gradient
PV atrial reversal wave cut-off velocity for elevated LVEDP
> = 35cm/s
PV atrial reversal wave cut-off duration for elevated LVEDP
> = 30 ms more than duration of mitral inflow A wave
Rapid deceleration of TR jet
Very severe TR
Regurgitant fraction equation
RF = RF / (forward SV + RF)
Mitral inflow in cor triatriatum
Forward flow in systole and diastole with 3 phases
LA volume calculation
= 0.85 * (Area 1 * Area 2) / Length
Typical mean LA pressure grade 1 DD
8-14mmHg
Typical mean LA pressure grade 2 DD
15-22mmHg
Typical mean LA pressure grade 3 DD
> 22mmHg
