Flashcards in ClinCorr 7- Echocardiography Deck (24):
The heart is routinely imaged from which three standard windows?
parasternal, apical, and subcostal (and suprasternal)- these are all cardiac window
For a parasternal view, where should the phased-array transducer be placed?
immediately to the left of the sternum in the 3rd or 4th intercostal space
marker should be facing the patient's right shoulder
What are cardiac window?
windows on the anterior chest wall through which an ultrasound beam can effectively reach the heart without being blocked
Is there any prep for a echocardiography? Does the patient need to fast?
What is the ideal patient position for an ECG using the parasternal or apical window?
left lateral decuibdeous (can be done supine)
What should be the frequency range of a cardiac probe?
During PLAX cardiac imaging, should the orientation marker be to the right or the left of the image?
Right. For all other cardiac (and all other ultrasound) images, it will be to the left by default.
Many years ago, echocardiographers adopted the convention of having the screen indicator oriented to the left side of the image. This is opposite to the convention used with ultrasounds of other organs, where the screen indicator is positioned to the right. This means that in all cardiac ultrasounds, the transducer indicator should be directed to the patient’s left side, with the exception of the PLAX view (where it is directed toward the patient’s right shoulder).
What are the ideal 'depths' for a) parasternal and b) subcostal or apical views
a) shallower 12-16 cm
b) deeper 16-22 cm
What is the best window to begin looking at the heart?
Where does the long axis of the heart run?
base of the heart near the right atrium (superior) to the apex of the heart
the probe marker should be oriented toward the patient's right shoulder
How do you perform a parasternal short-axis ECG?
The key to obtaining good short-axis views is to start with a high-quality parasternal long-axis image. First, center the transducer over the mitral valve in the PLAX view. Then, rotate the transducer 90 degrees, so that the indicator points toward the patient’s left shoulder. Be careful not to allow the transducer to slide on the chest as you do so. Fixing your hand on the patient while rotating the probe between your fingers (without rotating your wrist) will help keep the transducer in position. Be sure that the image of the LV cavity is circular, indicating a true cross-section. If the LV cavity appears oval, the beam is off-axis and interpretations of LV function and wall abnormalities will be erroneous. The other short-axis views are obtained by tilting the position of the transducer alternately toward the right shoulder and then progressively back toward the left hip from the same position on the chest
What are the four positions for obtaining a short axis parasternal view?
aortic valve, mitral valve, mid-ventricle, apex
What things will you see in a parasternal short axis aortic view?
LA, RA, RV, aortic valve, tricuspid valve
What things will you see in a parasternal short axis mitral view?
RV, mitral valve
What things will you see in a parasternal short axis mid-ventricle view?
RV, LV, papillary muscles, interventricular septum
What things will you see in a parasternal short axis apex view?
RV and LV
What things will you see in a parasternal long axis view?
LV, LA, aortic outflow tract, RV, AV valve, mitral valve, interventricular septum, posterior wall of the LV, and the pericardium
make sure to set the depth so the pericardium and the posterior wall of the LV are included
What is the difference between tilting and angling probes?
tilting- if you're looking at a probe that has the wide part to the right and the left, tilting would be moving the probe forward like the beginning of a person falling forward
angling- if you're looking at a probe that has the wide part to the right and the left, angling would be moving the left or the right side up
What could help optimize an image?
having the patient exhale deeply
In a parasternal long-axis view (and just in general), how much should the thickness of the LV increase during systole?
50% increase (and should contract toward the center of the cavity)
What is resolution?
the ability to distinguish nearby structures on an image
Image resolution is divided into axial, lateral, elevational and temporal components
What is axial resolution determined by?
primarily by the sound wave frequency. Higher frequencies enhance axial resolution, but cannot penetrate as deeply in the body.
What is elevational resolution determined by?
determined by the transducer’s width. Temporal resolution applies to moving structures.