Echocardiography Flashcards
what are the modes of echocardiography
- 2-dimensional
- M-mode
- doppler echocardiography
2-dimensional echo
main view; used to evaluate cardiac anatomy
long (sagittal) and short (transverse) planes
M-mode echo
motion; monitors movement at one spot over time
used to evaluate cardiac function
short (transverse) planes
doppler echocardiography
spectral and color
used to evaluate direction and speed (velocity) of blood flow
what direction do the doppler waves need to be relative to blood flow
parallel
what are the 2D views
R parasternal long axis: 4 and 5 chamber views
R parasternal short axis: LV, MV, basilar, and PA views
L apical: 4 and 5 chamber view
right parasternal long axis 4 chamber view
views L and some R heart
RV –> TV –> RA
LV –> MV –> LA
right parasternal long axis 5 chamber view
views aorta and AV valve
similar to 4 chamber view but angled to see aorta
RV –> TV –> RA
LV –> AV + MV –> AO + LA
right parasternal short axis LV view
“mushroom” view
views the LV and papillary muscles
right parasternal short axis MV view
“fish lips” view
views both leaflets of the MV
right parasternal short axis basilar view
“whale” and “mercedes” view
views the LA and aorta
good for identifying LA enlargement
what is the normal size of the LA
compare to the size of the aorta in right parasternal short axis basilar view
LA diameter should be <1.6x the diameter of the aorta
right parasternal short axis PA view
views the pulmonary artery and branches
PA should be less than or equal to the size of the aorta
left apical 4 chamber view
views regurgitation and velocity of blood flow on doppler
RV, LV
RA, LA
left apical 5 chamber view
views aorta and AV valve
similar to left apical 4 chamber view but angled to see aorta
RV, LV
RA, AO, LA
what are the M-mode views
R parasternal short axis LV, MV, basilar
evaluates motion over time in a single “ice-pick” view
depth: vertically
time: horizontally
when is systole vs diastole on m-mode
systole: shorter depth in ventricles
diastole: larger depth in ventricles
what m-mode view can you see the opening and closing of the mitral valve
R parasternal short axis MV view
makes an “m-shaped” wave consisting of E and A wave
what m-mode view can you see the opening and closing of the aortic valve
R parasternal short axis basilar view
makes an “O-shaped” wave
fractional shortening
index of contractility - NOT a direct measure due to the effect of pre/afterload
how to calculate fractional shortening
FS = [(LVDD - LVDS) / LVDD] x 100
LVDD: left ventricular diastolic diameter
LVDS: left ventricular systolic diameter
normal fractional shortening
dogs: 25-40%
cats: 35-50%
color flow doppler
detects the direction of blood flow
BART map on color flow doppler
pneumonic for direction of blood flow on color flow
blue = away from probe
red = toward probe
green/yellow = turbulent flow
what does green/yellow on color flow doppler indicate
turbulent blood flow
ex. regurgitation
spectral flow doppler
detects the velocity of flow
can be used to calculate the pressure gradient across a valve or shunt
how to calculate pressure gradient using spectral flow
Bernoulli’s equation:
deltaP = 4 x V^2
how can you tell direction of blood flow on spectral doppler
positive wave = blood flow towards probe
neutral wave = blood flow perpendicular to probe
negative wave = blood flow away from probe
what view is best for measuring aortic valve velocity
subcostal view
what are the uses for electrocardiography
- structural defects
- pericardial effusion
- blood flow direction and velocity
- calculate pressure gradients
difference between horse echos and SA
uses all the same views EXCEPT left apical due to size of chest
uses left parasternal long axis view instead
