The heart is a three-dimensional structure which, through fluoroscopy, may be visualized
two-dimensionally (Figures 1.1 – 1.2 ). In order to have a proper view of the cardiac
cavities as well as of the great vessels, fluoroscopic projections other than standard ones
are required.
Electrophysiological procedures usually relay on three radioscopic projections: frontal
posteroanterior (PA), right anterior oblique (RAO) (ranging between − 30 ° and − 45 ° ), and
left anterior oblique (LAO) (ranging between +30 ° and +45 ° ).
1
In the frontal PA view, the cardiac silhouettes ’ right border is defined, above, by the supe-
rior vena cava and, inferiorly, by the right atrium ’ s lateral wall. In case of considerable left
atrial dilatation, the left atrium may contribute to the shape of the right border of the heart
shadow.
The left border, inferiorly, is shaped by the anterior wall of the left ventricle while, supe-
riorly, a slight convexity is given by the left atrial appendage and the pulmonary artery ’ s
common trunk. Anatomically, the base of the heart is comprised primarily by the inferolat-
eral wall of the right ventricle, while the apex represents the left ventricular apex (Figures
1.3 – 1.5 ).
In the RAO projection, the heart shadow has an oblong shape with major axis running
superoinferiorly and toward the viewer so that we can see a right border, a left border, and
an inferior border. The right border is shaped by the posterior wall of the right atrium and
by the posterior wall of the left atrium. The left border is shaped by the superior wall of the
right ventricle (though the apex is mainly shaped by the left ventricular apex) and, above,
by the right ventricular outflow section; by varying the view from − 45 ° to − 60 ° and further,
the left ventricle progressively fades away from the right edge of the heart image. The base
of the heart coincides with the right ventricular inferior wall. This view shows very clearly
the atrioventricular groove, viewed in length-wise direction; therefore, it allows better dis-
tinction of the atrium from the ventricle. The RAO view should be used when evaluating
catheter ’ s anterior or posterior position, for both the right and the left heart cavities
(Figures 1.6 – 1.8 ).
In the LAO projection, the heart shadow appears as a globe in which we can distinguish
a right border, a left border, and an inferior border. The right border is shaped by the right
ventricular lateral wall and, above, by the right atrial appendage. The left border is defined
by the left ventricular lateral wall and, above, by the left atrium. By rotating up to +60 ° ,
the left atrium ’ s image progressively increases; at the same time, the ventricular section
becomes smaller until it fades away completely by rotating to +90 ° . Atrioventricular valve
rings are viewed enface. During the fluoroscopic procedure, the atrioventricular junction
can be identified by the difference in the pulsation of the atrial section compared with
Figure 1.1 Standard thoracic radiograph obtained in the posteroanterior ( PA ) projection. Thoracic
fluoroscopy enables easy visualization of both the heart and the vascular structures, as they appear
white, thus distinguishing them from the lungs which are radiolucent and appear black. Electrophysi-
ological procedures require fluoroscopic images to be carried out with the patient lying on his/her
back. In this position the diaphragm tends to rise and overlap the base of the heart
Figure 1.2 Standard thoracic radiograph obtained during deep inspiration in posteroanterior ( PA )
view. The presence of a Carpentier-Edwards Physio Ring at mitral annulus allows to visualize directly
the left atrioventricular groove
that of the ventricular one. The LAO view should be used to evaluate the lateral or medial
catheter position and allows better distinction of the right heart cavities from the left heart
cavities and, for each cavity, the free walls from the septal ones (Figures. 1.9 – 1.11 ).
It is useful to remember that, in oblique projections, shadow of the spine is always found
opposite to the type of used projection. In the right oblique view, the spine will be found on
the left, whereas in the left oblique view it will be seen on the right.
two-dimensionally (Figures 1.1 – 1.2 ). In order to have a proper view of the cardiac
cavities as well as of the great vessels, fluoroscopic projections other than standard ones
are required.
Electrophysiological procedures usually relay on three radioscopic projections: frontal
posteroanterior (PA), right anterior oblique (RAO) (ranging between − 30 ° and − 45 ° ), and
left anterior oblique (LAO) (ranging between +30 ° and +45 ° ).
1
In the frontal PA view, the cardiac silhouettes ’ right border is defined, above, by the supe-
rior vena cava and, inferiorly, by the right atrium ’ s lateral wall. In case of considerable left
atrial dilatation, the left atrium may contribute to the shape of the right border of the heart
shadow.
The left border, inferiorly, is shaped by the anterior wall of the left ventricle while, supe-
riorly, a slight convexity is given by the left atrial appendage and the pulmonary artery ’ s
common trunk. Anatomically, the base of the heart is comprised primarily by the inferolat-
eral wall of the right ventricle, while the apex represents the left ventricular apex (Figures
1.3 – 1.5 ).
In the RAO projection, the heart shadow has an oblong shape with major axis running
superoinferiorly and toward the viewer so that we can see a right border, a left border, and
an inferior border. The right border is shaped by the posterior wall of the right atrium and
by the posterior wall of the left atrium. The left border is shaped by the superior wall of the
right ventricle (though the apex is mainly shaped by the left ventricular apex) and, above,
by the right ventricular outflow section; by varying the view from − 45 ° to − 60 ° and further,
the left ventricle progressively fades away from the right edge of the heart image. The base
of the heart coincides with the right ventricular inferior wall. This view shows very clearly
the atrioventricular groove, viewed in length-wise direction; therefore, it allows better dis-
tinction of the atrium from the ventricle. The RAO view should be used when evaluating
catheter ’ s anterior or posterior position, for both the right and the left heart cavities
(Figures 1.6 – 1.8 ).
In the LAO projection, the heart shadow appears as a globe in which we can distinguish
a right border, a left border, and an inferior border. The right border is shaped by the right
ventricular lateral wall and, above, by the right atrial appendage. The left border is defined
by the left ventricular lateral wall and, above, by the left atrium. By rotating up to +60 ° ,
the left atrium ’ s image progressively increases; at the same time, the ventricular section
becomes smaller until it fades away completely by rotating to +90 ° . Atrioventricular valve
rings are viewed enface. During the fluoroscopic procedure, the atrioventricular junction
can be identified by the difference in the pulsation of the atrial section compared with
Figure 1.1 Standard thoracic radiograph obtained in the posteroanterior ( PA ) projection. Thoracic fluoroscopy enables easy visualization of both the heart and the vascular structures, as they appear
white, thus distinguishing them from the lungs which are radiolucent and appear black. Electrophysi-
ological procedures require fluoroscopic images to be carried out with the patient lying on his/her
back. In this position the diaphragm tends to rise and overlap the base of the heart
Figure 1.2 Standard thoracic radiograph obtained during deep inspiration in posteroanterior ( PA )
view. The presence of a Carpentier-Edwards Physio Ring at mitral annulus allows to visualize directly
the left atrioventricular groove
that of the ventricular one. The LAO view should be used to evaluate the lateral or medial catheter position and allows better distinction of the right heart cavities from the left heart
cavities and, for each cavity, the free walls from the septal ones (Figures. 1.9 – 1.11 ).
It is useful to remember that, in oblique projections, shadow of the spine is always found
opposite to the type of used projection. In the right oblique view, the spine will be found on
the left, whereas in the left oblique view it will be seen on the right.
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