o_1977r8vv9vk1ts2ms0kd8pksa.pdf

470 D. Maulik
Fig. 32.8. Two-dimensional echocardiogram of the fetal
heart. Left: Long-axis view of the left ventricular outflow.
AO aorta, LA left atrium, LV left ventricle, RV right ventricle.
Right: Long-axis views of the right ventricular outflow. PA
main pulmonary artery, LV left ventricle, RV right ventricle
with the spine anterior) along its central axis with
slight fanning motion cephalad toward the left
shoulder of the fetus reveals the left parasternal longaxis
view of the left ventricle and the aortic outflow
tract (Fig. 32.6). The transition from the four-chamber
plane to this view is swift, requiring only minimal
transducer manipulation. Further slight rotation
and fanning motion of the beam in the longitudinal
plane in the left parasternal area reveals the right
ventricle and the pulmonic outflow tract (Fig. 32.7).
These views allow assessment of the right and left
ventricular outflow tracts (Fig. 32.8). Particularly
noteworthy is the aortic-pulmonary crossover relationship,
which is characteristic of normal cardiac
anatomy. Absence of this feature is pathognomonic of
great artery transposition.
Parasternal Short-Axis View
Ventricular short-axis views may be obtained by rotating
the transducer approximately 908 from the
four-chamber view and moving the beam plane perpendicular
to and along the long axis of the ventricles,
starting at the cardiac apex and concluding at
the cardiac base (Fig. 32.9). This maneuver generates
cross-sectional images of the ventricles at the apex,
midcavity, atrioventricular junctions, and the root of
the great vessels (aortic short-axis pulmonic outflow
view). These approaches allow assessment of the ventricles,
the mitral and tricuspid valves and orifices,
and the ventricular outflow tracts, especially the pulmonary
arteries (Fig. 32.10).
Fig. 32.9. Method for obtaining ventricular short-axis
(parasternal) view of the fetal heart at the level of the cardiac
base and the origin of the great arteries. Far left: Orientation
of the transducer plane in relation to the fetal
thorax. Middle: Echocardiographic plane in relation to the
fetal heart. PA pulmonary artery, PV pulmonary valve, RV
right ventricle, TV tricuspid valve, IVC inferior vena cava, LA
left atrium, RA right atrium
Ductal and Aortic Arch: Long-Axis View
From the four-chamber plane, the transducer should be
rotated (clockwise with fetal spine posterior) to align
the imaging plane to the left of the fetal midline sagittal
plane (Fig. 32.11). This maneuver reveals the long-axis
view of the pulmonic artery-ductal arch (Fig. 32.12).
With fine manipulation and slight tilting motion of
the transducer, the imaging plane can be projected
slightly oblique in reference to the sagittal plane, traversing
from the right anterior thorax to the left of
the fetal spine with an occipitoposterior position
(Fig. 32.13), or from the left of the spine to the right