Chamber quantification/functional assessment Flashcards
what is the equation for fractional shortening and what is the normal range?
FS= (LVIDd - LVIDs) / LVIDd x 100
normal range: 25-40%
what is normal value for septal E-point separation and what does it mean if it’s abnormal?
normal is < 7mm, an elevated septal E-point separation suggests low LV systolic function
what is B-bump on mitral valve M-mode and what does it connote?
B-bump on MV M-mode is when there is a third bump after the E and A excursions of the mitral valve, due to interrupted closure of the mitral valve ahead of systole, seen in patients with high LVEDP
what is the equation for right ventricular index of myocardial performance and what are the abnormal cutoffs?
RIMP= (IVCT + IVRT) / RV ET or (TV closure to open time - RV ET) / RV ET
abnormal is > 0.43 for PW and > 0.54 for TDI
What is the equation for calculating PCWP using mitral E velocity and Vp (velocity of propagation on color M-mode of mitral valve)?
PCWP= 4.6 + 5.27(E/Vp)
What is the equation for calculating LAP using mitral E velocity and mitral annulus e’ velocity?
LAP= 1.9 + 1.24(E/e’)
How can one calculate PVR using PASP and PADP?
PVR= (mean pulm pressure - LAP) / Qp
Mean pulm pressure= 2/3(PADP) + 1/3 PASP
So PVR= 2/3PADP + 1/3PASP / Qp …gives you the PVR in Woods units
How is dP/dt calculated?
dP/dt gives a sense of systolic function
dP/dt= (change in pressure between pressure at 1m/s and 3m/s) / (relative time interval between 1m/s and 3/ms expressed in seconds not milliseconds)
= 36-4/ relative time interval
what are the upper limits of normal for 3D derived EDV and ESV
EDV: 79mL for men and 71 for women
ESV: 32 for men and 28 for women
How is dP/dt calculated?
dP/dt gives a sense of systolic function
dP/dt= (change in pressure between pressure at 1m/s and 3m/s) / (relative time interval between 1m/s and 3/ms expressed in seconds not milliseconds)
what is normal dP/dt?
greater than or equal to 1200mmHg/s
what does elevated atrial reversal peak velocity signify?
atrial reversal peak velocity of >/= 35cm/s suggests elevated left ventricular end diastolic pressure
also, atrial reversal wave that is >/= 30ms longer in duration than the mitral inflow A wave is also suggestive of high LVEDP
(both the duration and peak velocity of the atrial reversal wave increases when LVEP is high)
what does elevated LAP do to the ratio of systolic wave peak velocity to diastolic wave peak velocity of pulmonary venous tracings
S/D ratio decreases when LAP is elevated
what is annulus paradoxus?
the concept that in constrictive pericarditis there is an inverse relationship between E/e’ and PCWP rather than direct relationship
what is the equation to calculate left atrial volume using area-length method?
LAV= 8 x (area in A4C) x (area in A2C) / 3 x pi x length
where length is the shorter of the two lengths (A4C vs A2C)
what is normal value for velocity of propagation in young people vs elderly?
young: normal Vp is > 55
elderly: normal Vp is > 45
what is annulus paradoxus?
the concept that in constrictive pericarditis there is an inverse relationship between E/e’ and PCWP
what is the normal range for radial strain?
40-60%
what’s the equation for LV mass?
LV mass= 1.04[(IVS + LVIDd + PWT)^3 - LVIDd^3] - 13.6
What is the timing of contraction like in ischemia?
In ischemia there should be delayed contraction in visual assessment and delayed peak strain on strain curves?
how does valsalva help with diastology?
helps distinguish normal from pseudo normal:
decrease in E/A ration of 50% or more with valsalva is suggestive of pseudo normal filling or high LA pressures (using absolute A, in other words peak A minus E height at onset of A)
what does pulmonary vein Ar velocity greater than or equal to 35cm/s suggest?
elevated LVEDP
how is Ar - A duration difference in PV flow used?
Ar-A difference (difference between duration of PV Ar duration and mitral A wave duration) of > 30ms suggests elevated LVEDP which can help identify early phases of diastolic dysfunction and is an age-independent variable
in pulm vein analysis what is systolic filling fraction and how is it used?
systolic filling fraction= VTI of S wave / (VTI of S wave + VTI of D wave)
systolic filling fraction < 40% suggests low LA compliance and increased mean LA pressure
what is considered a normal flow propagation velocity?
flow propagation velocity (Vp) > 50 cm/s is normal
how does E/Vp predict PCWP?
E/Vp >/= 2.5 predicts PCWP > 15mmHg with reasonable accuracy
What is the cascade of abnormalities in ischemia
Normal —> perfusion abnormality —> diastolic dysfunction—> strain abnormality —> systolic dysfunction —> hemodynamic abnormalities—> ECG abnormality—> chest pain
what is the cutoff for global longitudinal strain which predicts subclinical LV dysfunction?
reduction in GLS of > 15%
How is cardiotoxicity defined when it comes to LVEF?
reduction in LVEF of > 10% to cause EF < 53%
How can mean PA pressure be calculated using PV acceleration time?
mPAP= 80 - 0.5(PV acceleration time)
how should RV wall thickness be measured by ASE guidelines and what’s the cutoff for RVH?
ideally measured in subcostal view where RV free wall is perpendicular to US beam;
RVH by echo is wall thickness >/= 5mm
