Page 2199 - Cote clinical veterinary advisor dogs and cats 4th

Echocardiography 1095

• Use high-frequency transducers to obtain from the four-chamber view into a slightly the apex of the heart as possible, often
quality images of near-field structures. more craniodorsal orientation, revealing the around the seventh ICS and tilted to
VetBooks.ir Doppler (color, pulse wave, continuous wave) • Short-axis views: rotate the transducer ≈90° left caudal to right cranial orientation and
point cranially. The beam plane is in a
• Use low-frequency transducers for quality
left ventricular outflow tract, aortic valve,
and aortic root.
signals.
then directed dorsally toward the heart
• Adjust depth of the real-time image to fill
view (keep probe in same position except
the field of view (reduce amount of lung toward the sternum from the four-chamber base, revealing the ventricles in the near
field closest to the transducer and the atria
field). for the rotation) such that the beam plane in the far field (heart is oriented vertically;
• Adjust gain to avoid producing a white, is oriented perpendicular to the long axis LV, mitral valve, and left atrium should
distorted image due to a high setting; too of the heart, with the transducer index appear to the right). Modest cranial tilting
low a setting will produce a weak signal. mark pointing cranioventrally toward the of the beam from the above view will
• Remember the concept of blue/away and animal’s elbow (proper orientation identified bring the left ventricular outflow region
red/toward (BART) for color-flow Doppler by circular symmetry of the left ventricle into view (five-chamber view).
studies. [LV] or aortic root). Five standard transverse • Left cranial parasternal location: the location
images (LV with papillary muscles, LV at is between the left third and fourth ICS,
Procedure mitral chordae tendineae level, LV at mitral between the sternum and costochondral Procedures and Techniques
• Image quality is improved in lateral valve level, heart base–aorta/left atrium junctions.
recumbency; however, dogs and cats may level, and heart base–pulmonary artery) are ○ Long-axis views: with the transducer
be examined in a standing, sitting, or sternal obtained from this position by pivoting the index mark pointing cranially and the
position. transducer from the apex to the base of the beam plane oriented parallel to the long
• The ultrasound machine’s ECG clips are heart (caudal/ventral to cranial/dorsal). axis of the body and heart, a view of
attached to the legs as recommended by the • Turn the animal over into left lateral recum- the LV outflow tract, aortic valve, and
manufacturer for measurements and timing bency, with the animal’s limbs still toward ascending aorta is obtained (LV will be
within the cardiac cycle. the sonographer. displayed to the left and aorta to the right).
• Starting in right lateral recumbency (animal’s • Left caudal (apical) parasternal location: the From this position, angling of the beam
limbs toward the examiner), the right para- location is between the left fifth and seventh ventrally (toward the sternum) to the aorta
sternal location (window) is between the right ICS, as close to the sternum as possible brings out the right atrium/right auricle,
third and sixth ICS, between the sternum (landmark: palpable left apical heartbeat). tricuspid valve, and inflow region of the
and costochondral junctions (landmark: ○ Left apical two-chamber views: the right ventricle (displayed to the right, with
palpate right precordial heartbeat and place transducer index mark points toward the the LV noted to the left). Angling the
transducer at this location to start). Attention heart base (dorsal), and the beam plane transducer dorsally (transducer is almost
is paid to having the assistant restrain the is parallel to the long axis of the heart horizontal and parallel with the table) in
animal with the forelimbs drawn far enough to visualize the left side of the heart (left relation to the ascending aorta produces
cranially to open the axilla/acoustic window. atrium, LV, and mitral valve). Slight rota- a view of the main pulmonary artery,
• Long-axis views: beam plane is oriented tion of the transducer into a craniodorsal pulmonary valve, and right ventricular
slightly clockwise from perpendicular to to caudoventral orientation reveals LV, LV outflow tract.
long axis of the body, parallel to the long outflow tract, aortic valve, and aortic root ○ Short-axis views: remain in the same loca-
axis of the heart, and with the transducer in a long-axis view. tion as for the cranial long axis, and rotate
index mark pointing toward the heart base ○ Left apical four-chamber views: this is the transducer until the transducer’s index
(craniodorsally, approximately toward the the only view in which the transducer mark is toward the thoracic spine (dorsally,
animal’s shoulder). The following two views index mark points to the left and caudally, ≈90° from the location of long-axis view;
are obtained: first, a four-chamber view with opposite of all other views. NOTE: The aorta should appear circular in the center
the ventricles displayed to the left and the transducer should be as far caudally toward of the image). The right ventricular
atria to the right; second, a view obtained
by slight clockwise rotation of the transducer

ECHOCARDIOGRAPHY Right parasternal, short-axis view at the left ventricular
papillary muscle level in same dog. From this view, gentle pivoting motion (caudal/
ECHOCARDIOGRAPHY Right parasternal, four-chamber, long-axis view in a ventral to cranial/dorsal) of the transducer beam toward the base reveals the other
normal dog (obtained without shaving). IVS, Interventricular septum; LA, left atrium; four standard views obtained from this location. APM, Anterior papillary muscle;
LV, left ventricle; LVW, left ventricular wall; PV, pulmonary vein; RA, right atrium; IVS, interventricular septum; LV, left ventricle; PPM, posterior papillary muscle;
RV, right ventricle; RVW, right ventricular wall. RV, right ventricle.

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