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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3752_Библиотеки_им_академика_М_И_Перельмана
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the use of CCTA versus CMR depend on multiple factors,
including the age of the patient, need for assessment of
coronary anatomy, and presence of pacemakers or ICDs.
CCTA is useful for determining anatomy and physiology
important to surgical planning, particularly in patients with
non-MR conditional pacemakers and implantable cardiac
defi brillators as CMR can be limited in use in these settings
[ 49 – 51 ]. The associated radiation with CCTA is a major
issue, although techniques to minimize dose are being
advanced [ 52 – 55 ].
Image defi nition of thoracic and abdominal situs, rotational abnormalities of thoracic vasculature, atrial and ventricular septal defects, shunts and fi stulas, and anomalous
large and small vessel anatomy can be achieved and defi ned
in one 3-D data set (Figs. 22.17 , 22.18 , 22.19 , 22.20 , 22.21 ,
and 22.22 , Videos 3, 4, 5 and 6). CCTA is useful for specifi c
questions that other imaging modalities are unable to answer
as well as for creation of comprehensive roadmaps, particularly when the previous history of anatomy and previous surgical interventions are not known or well-defi ned. Innovations
Fig. 22.8 Surgical clip artifacts
( white arrows ) with a clip
( double white arrow ) obscuring
the anastomosis of the left
internal mammary artery graft to
the left anterior descending
coronary artery
ab
Fig. 22.9 Panel ( a ) A 3-D view of
the aortic root demonstrating coaxial
2-D double oblique views of the
aortic annulus, sinuses of Valsalva,
sinotubular junction and ascending
aorta. Panel ( b ) A 2-D double
oblique maximal intensity projection
demonstrating the distance from the
left main coronary artery to the
aortic valve annulus
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in scanner hardware and software have lowered the radiation
doses allowing for imaging in infants and children with congenital heart disease [ 54 , 55 , 57 ].
Post-surgical Sequelae: Tetralogy of Fallot,
Single Ventricle Physiology and Transposition
of the Great Arteries
In complex congenital heart disease, such as tetralogy of
Fallot, single ventricle physiology and transposition of the
great arteries, CCTA can provide assessment of the unoperated state as well as for sequelae of operative palliation
or repair. In the pre-operative state, CCTA is useful for
characterizing anomalous coronary artery anatomy for surgical planning [ 58 ]. In the post-operative setting of recon-
structed right ventricular outfl ow tract with pulmonary
valve regurgitation, cardiovascular magnetic resonance
imaging (CMR) is a gold standard of measurement for
assessment of right ventricular size, right ventricular function, and pulmonary valve fractional regurgitation. Some
of these patients, though, have cardiac devices, potentially
limiting the use of CMR. In comparison to CMR, CCTA
assessment of right ventricular function and pulmonary
regurgitant fraction, calculated by the difference between
biventricular systolic volume difference, can be achieved
with the caveats that right ventricular volume can be overestimated and pulmonic regurgitant fraction underestimated using CMR as a gold standard [ 59 ]. CCTA can
characterize the anatomy of the reconstructed pulmonary
outfl ow tract and pulmonary vasculature for pulmonary
artery stenosis or enlargement/aneurysm (Videos 7 and 8).
a
cd
b
Fig. 22.10 Bicuspid aortic valve endocarditis with arterial emboli.
Due to high risk of invasive coronary artery angiography in this scenario, CCTA was performed prior to aortic valve replacement. The
study demonstrated no evidence of aortic root abscess, aortic pseudoaneurysm, or obstructive coronary artery disease. Panel ( a ) A 2-D double
oblique view demonstrating a large, friable, vegetation on bicuspid aortic valve leafl et. Panel ( b ) A 2-D double oblique image of the aortic root
viewed in long axis showing the vegetation to be in close proximity to
the sinuses of Valsalva. Panel ( c ) A curved multiplanar reformatted
view and corresponding 3-D reconstruction showing a patent left coronary artery circulation. Panel ( d ) A curved multiplanar reformatted
view and corresponding 3-D reconstruction showing a patent right
coronary artery. AoV aortic valve, Cx circumfl ex coronary artery, LAD
left anterior descending coronary artery, LM left main coronary artery,
VEG vegetation, RCA right coronary artery
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For patients with surgical repair for single ventricle physiology, opacifi cation of the complete Fontan circuit can
require specialized injection protocols, with venous injection
from two sites (upper and lower extremity) or delayed timing
of imaging relative to injection in order to fully opacify the
Fontan and pulmonary vasculature [ 60 ]. In surgically treated
transposition of the great arteries, CCTA can provide
assessment of stents and baffl es, re-implanted coronary
arteries, and assessment of ventricular function [ 61 – 64 ].
Atrial and ventricular sepal defects can occur as single
anomalies or in association with additional complex anatomy.
CCTA can characterize defects, providing such details as
double-oblique assessment of coaxial defect size and rim
characteristics as well as providing preoperative assessment
for other cardiovascular anomalies which may need to be
addressed at the time of surgical repair. In patients with
septal defects with identifi ed complex additional anomalies,
CCTA provides information important to surgical decisionmaking and planning [ 56 , 65 – 68 ].
Patent Ductus Arteriosus
In patients with patent ductus arteriosus, CCTA provides
important information for deciding between surgical
and percutaneous closure approach through precise characterization of morphology and size and assessment for other
associated cardiothoracic anomalies facilitating appropriate
sizing of ductus occlusion devices (Fig. 22.23 ). Options for
surgical versus percutaneous closure are dependent on patent
ductus arteriosus size, morphology, and location and orifi ce
size of the aortic and pulmonary artery insertions. A percutaneous approach may be preferable for a ductal size of less
than 3 mm in diameter (coil occlusion) and 3–14 mm (coil or
device occlusion) [ 69 ]. Ductal size of greater than 14 mm
and those with complex morphology are associated with
increased risk of complications with percutaneous closure
and surgical closure is usually performed, although in certain
situations in high risk surgical patients, percutaneous closure
has been employed [ 70 ].
Anomalous Coronary Arteries
Specifi c morphologies of anomalous coronary arteries can
lead to ischemia, infarction, and sudden cardiac death.
Decisions regarding potential surgical therapy for correction depend on identifi cation of high risk anatomy in the
appropriate clinical scenario. The CT imager should have
an understanding of how these anatomic details affect surgical decision-making, planning and performance of procedures. CCTA can characterize detailed anatomy for surgical
decisions relating to anomalous coronary arteries. Anatomic
details include individual coronary artery presence or
absence, origin, ostial characteristics, course, termination,
presence of coronary artery disease or aneurysm, and 3-D
Fig. 22.11 Multiplane views showing the relationship of an aortic pseudoaneurysm ( black arrows ) to the right coronary artery ( white arrows ) in
a patient with aortic valve endocarditis
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relationship to other cardiovascular structures (Figs. 22.24 ,
22.25 , 22.26 , 22.27 , 22.28 , 22.29 , 22.30 , 22.31 , 22.32 ,
22.33 , 22.34 , 22.35 , 22.36 , 22.37 , and 22.38 , Videos 9
and 10). In regard to the origin, the coronary artery can arise
from the aortic sinuses, other locations on the aorta or other
vascular structures. Viewing the aortic sinuses as a clock
face in the axial plane, the normal coronary artery origins
are at approximately 11 o’clock for right coronary artery
and 4 o’clock for left main. Ostial morphology can include
a separate ostium, a shared ostium with another coronary
artery, or an ostium off of another coronary artery. Ostial
morphologies include presence of a slit-like ostium, and for
retrospectively gated studies, dynamic ostial compression
due to adjacent vascular structures. For coronary arteries
arising from the contralateral sinus, there are four main
pathways for the anomalous artery to course back to its
usual myocardial distribution: pre- pulmonic, inter-arterial,
trans-septal, or retro-aortic. The termination of an anomalous coronary artery can be into a capillary distribution
usual for a given coronary artery, the capillary distribution
in another myocardial segment, a cardiac chamber, or
another arterial or venous vascular structure. The lumen can
have no evidence of coronary atherosclerosis, nonobstructive coronary atherosclerosis, obstructive coronary
artery disease, or aneurysmal dilatation.
High risk features for cardiovascular events include
absence of a coronary artery with inadequate compensatory
arterial supply to a myocardial distribution, coronary artery
take-off from the contralateral sinus with a slit-like ostium
and inter- arterial course, or an anomalous coronary artery
ab
cd
Fig. 22.12 Aortic valve endocarditis involving a mechanical valve
with paravalvular pseudoaneurysm/contained rupture. Panels ( a–c )
Multiple 2-D double oblique views demonstrate the aortic valve pseudoaneurysm/contained rupture ( white arrows ) extending along the
superior aspect of the right atrioventricular groove. Panel ( d ) A 2-D
double oblique view demonstrating the pseudoaneurysm/contained rupture ( black arrows ) causing narrowing of the proximal right coronary
artery, which subsequently courses into the pericardial sac with right
atrial hemopericardium/hematoma ( white arrows ) causing severe right
atrial compression. AoV aortic valve, LA left atrium, LAD left anterior
descending coronary artery, LM left main coronary artery, LV left ven-
tricle, PA pulmonary artery, RA right atrium, RCA right coronary artery,
RV right ventricle
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arising from another structure such as the pulmonary artery.
Pre-pulmonic, intra- septal and retro-aortic courses are usually
low risk morphologies [ 35 , 71 ]. For high risk anatomy in the
appropriate clinical situation, detailed characterization of the
anomalous coronary anatomy defi nes the available surgical
approaches including reimplantation of a coronary artery,
unroofi ng of a coronary artery, bypass of a coronary artery, or
translocation of other cardiovascular structures impeding fl ow
to a coronary artery [ 69 , 72 ]. Scenarios of bypass of a coro-
nary artery require signifi cant stenosis of the artery as otherwise competitive fl ow can lead to poor maturation or closure
of the bypass graft. The surgical approach to a coronary artery
off of the pulmonary artery is reimplantation of the coronary
artery. Surgical approaches to an interarterial course depend
on the location and characteristics of the anomalous coronary
artery ostium. For an intramural aortic course with a slit-like
ostium above the sinotubular junction, the coronary artery can
be unroofed, whereas, below the sinotubular junction the
artery can be fenestrated. For a separate ostium without an
intramural aortic course, the artery can be reimplanted. For a
shared ostium without an intramural course, unroofi ng or
reimplantation would not be feasible, and therefore the pulmonary artery can be translocated. In anomalous coronary
arteries with obstructive coronary artery disease, coronary
artery bypass grafting can be performed. This is not feasible
in the other scenarios as there would be competitive fl ow due
to the lack of coronary artery disease. In regard to abnormal
termination of a coronary artery into a venous structure, either
percutaneous or surgical occlusion can be performed depending on the caliber and tortuosity of the vessel.
CCTA Imaging Related to Surgery
for Advanced Heart Failure
In the setting of coronary artery disease associated with
severe ischemic cardiomyopathy, challenging decisions
relate to transplant versus high risk coronary artery bypass
surgery, often with additional decisions as to valvular repair
or replacement and ventricular aneurysmectomy. Assessment
of myocardial viability has become important to the preprocedure decision-making process. CMR has played an
important role due to the ability to assess for infarct related
fi brosis as well as regional contractility (Fig. 22.39 ) [ 73 – 76 ].
These images can also be used for decision-making regarding viability and ventricular dimensions for planning of
abc
de f
Fig. 22.13 Mechanical aortic valve endocarditis (same case as Fig. 22.12).
Serial virtual sternotomy 3-D reconstructions demonstrating the anatomy
from anterior to posterior ( a – f ). The pseudoaneurysm/contained rupture
( white arrows ) extends along the superior aspect of the right atrioventricu-
lar groove, causing narrowing of the proximal right coronary artery. The
pseudoaneurysm/contained rupture subsequently courses into the pericardial sac with right atrial hemopericardium/ hematoma ( black arrows ). RA
Right atrium, RCA right coronary artery, RV right ventricle
Fig. 22.14 Images demonstrating an immobile thrombus on the anterior leafl et of a mechanical prosthetic mitral valve which caused the
leafl et to be immobile
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revascularization. More recently, CCTA delayed enhancement imaging has been shown to reliably demonstrate fi brosis associated with myocardial infarction. In animal models,
delayed contrast imaging has been shown to correlate with
acute and chronic infarct shape and transmurality including
assessment for necrosis in the acute setting [ 77 ]. This tech-
nique requires re-imaging 10–15 min after administration of
iodinated contrast and therefore requires additional radiation. The technique has been demonstrated to correlate with
thallium SPECT assessment of viability [ 78 ]. In the setting
of acute myocardial infarction, CCTA delayed enhancement
correlates with CMR assessment of viability [ 79 ]. Delayed
Fig. 22.15 Repaired Tetralogy of Fallot with a retroaortic left main
and duplication of arterial supply to the left anterior descending coronary artery distribution from left and right coronary arteries in the setting of stenosis of the pulmonary valve conduit. 3-D reconstructions
( upper panels ) demonstrate a long left main arising from the left coro-
nary sinus which courses retroaortic between the aorta and the left
atrium and subsequently gives off a left anterior descending coronary
artery and circumfl ex coronary artery. The right coronary sinus gives
off a single short ostium which subsequently gives off a right coronary
artery that traverses anteriorly between the aorta and a heavily calcifi ed
pulmonary conduit, and a branch which courses within the vascular distribution of the left ventricular anterior wall and septum. There is therefore duplication of arterial supply to the left ventricular anterior wall
distribution. 2-D thick maximum intensity projection views ( lower pan-
els ) show the coronary sinuses are rotated clockwise. Consequently, the
left main coronary artery originates more posterior than usual, at
approximately the 7 o’clock location on the aortic clock face in the
axial view. The right coronary artery origin is likewise rotated clockwise, with the ostium at the 2 o’clock location. Percutaneous intervention for repair of the homograft stenosis was inadvisable due to the
close proximity of the right coronary artery to the pulmonary conduit.
Given the close proximity of cardiovascular structures to the sternum,
the patient was placed on cardiopulmonary bypass via right groin vessels prior to redo sternotomy in order to decompress the right ventricle.
Revision of the right ventricular outfl ow tract, and pulmonary valve
replacement were performed. During conduit/homograft resection, the
posterior layer of the conduit was left intact in order to avoid injury to
the anomalous right coronary artery. Ao aorta, CX circumfl ex coronary
artery, LAD left anterior descending coronary artery, LM left main coro-
nary artery, PA pulmonary artery, RCA right coronary artery, RV right
ventricle (Reprinted from Shinbane et al. [
35 ] with permission from
SAGE Publications)
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enhancement imaging can also be performed immediately
after cardiac catheterization without contrast reinjection
(Fig. 22.40 ). In preliminary studies in this setting, the degree
of CCTA delayed enhancement was associated with increased
subsequent heart failure admissions, correlated with low
dose dobutamine assessment of viability, was an independent predictor of future cardiovascular events, and correlated
with angiographic and clinical assessment of reperfusion
with percutaneous coronary intervention [ 80 – 84 ]. As tech-
niques evolve, CCTA delayed enhancement imaging may
ultimately serve in a similar capacity to CMR for preoperative decision- making and planning.
Ventricular assist devices have become an integral part of
advanced heart failure management as bridges to cardiac
a b c
Fig. 22.16 Distal right coronary artery fi stula to the left ventricle at
level of mitral annulus in patient with a previous history of mitral valve
surgery. Panel ( a ) 3-D view demonstrating the distal the aneurysmal
distal right coronary artery ( arrow ). Panel ( b ) Curved multiplanar refor-
matted view of the distal the aneurysmal distal right coronary artery
( arrow ). Panel ( c ) A 2-D double oblique view of the fi stulous connec-
tion of the aneurysmal distal right coronary artery to the left ventricle at
the level of the mitral annulus ( arrow ). LV left ventricle, RV right ven-
tricle, LA left atrium, LV left ventricle, RCA right coronary artery
ab
Fig. 22.17 Presurgical assessment for repair of atrial septal defect. ( a ) 2-D axial view showing a large secundum atrial septal defect. ( b ) Curved
multiplanar reformat demonstrating no evidence of obstructive coronary artery disease in the right coronary artery segment shown
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ab
Fig. 22.19 Restrictive mid anteroseptal ventricular septal defect due to
old anterior myocardial infarction with myocardial wall thinning and
contrast evidence of left to right fl ow. Panel ( a ) A 3-D reconstruction
demonstrating the ventricular septal defect ( arrow ). Panel ( b ) A 2-D
double oblique view of the ventricular septal defect ( arrow ). LV left
ventricle, RV right ventricle
Fig. 22.18 A restrictive apical muscular ventricular septal defect with
a circuitous course. The defect is oriented anteroposterior on the left
ventricular side septum but courses laterally on the right ventricular
side. The presence of prominent right ventricular apical muscle bands
also contributes to the circuitous course of the ventricular septal defect.
Panel ( a ) A 3-D coronal reconstruction demonstrating the level of the
level of the ventricular septal defect ( arrow ). Panel ( b ) A 3-D axial
reconstruction demonstrating the ventricular septal defect ( arrow ).
Panel ( c ) A 2-D double oblique view of the ventricular septal defect
( arrow )
ac
b
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ab
c
d
Fig. 22.20 CCTA demonstrating D Transposition of great arteries, status post previous interatrial baffl e, with additional fi nding of patent ductus arteriosus. Panel ( a ) A 3-D reconstruction. Panel ( b ) A 2-D axial
view demonstrating the aorta to be anterior and slightly rightward of the
enlarged main pulmonary artery. Panel ( c ) A 2-D axial view demon-
strating the anatomic positions and physiologic relationships of the
ventricles. The systemic ventricle (morphologic right ventricle) is in
close proximity to the sternum. Panel ( d ) Virtual endovascular view of
the patent baffl e as it enters the left atrium. Ao aorta, LV left ventricle,
PA pulmonary artery, PDA patent ductus arteriosus, RLPV right lower
pulmonary vein, RUPV right upper pulmonary vein, RV right ventricle
abc
Fig. 22.21 CCTA showing D transposition of the great arteries, status
post interatrial baffl e. Panel ( a ) A 3-D reconstruction coronal view with
skeletal structure. Panel ( b ) A 3-D reconstruction coronal view with
skeletal structure removed. Panel ( c ) A 3-D reconstruction coronal view
highlighting the coronary artery anatomy. There is mirror image loca-
tion of the right coronary artery which arises posteriorly on the aortic
sinus and supplies the pulmonary ventricle (morphologic left ventricle).
Ao aorta, LAD left anterior descending coronary artery, PA pulmonary
artery, RCA right coronary artery, RV right ventricle
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transplant as well as destination devices for those patients
who are not candidates for transplant. CCTA can be helpful
in assessment of feasibility of ventricular assist device
implantation in children and small adults, as well as to identify potential obstacles to sternotomy incision for placement
(Fig. 22.41 , Video 11). In patients with implanted ventricular
assist devices, CCTA can identify components of the system
to assess for etiologies of ventricular assist device malfunction
(Fig. 22.42 ). In patients with pulsatile devices, electrocardio-
graphic-gating can be utilized, while in those continuousfl ow devices peripheral pulse-gating can be used to assess for
etiologies of low output and low fl ow states [ 85 ]. CCTA can
assess for issues throughout the system, including: infl ow
obstruction by papillary muscle, infl ow cannula malposition,
thrombus, air in the cannula, outfl ow cannula kinking or malposition, and aortic root thrombus [ 85 – 89 ].
In heart transplant patients, CCTA has been preliminarily
studied to assess coronary arteries for chronic allograft vasculopathy. The high negative predictive value of CCTA may
potentially be useful in this setting [ 90 – 93 ]. Limitations in
assessment of coronary branch vessels less than 1.5 mm for
chronic allograft vasculopathy, nephrotoxic effects of iodinated contrast, and issues of timing and frequency of assessment leading to potential cumulative effects of radiation in
ab c
Fig. 22.22 Unoperated congenitally corrected transposition of the
great arteries, dextrocardia, nonrestrictive ventricular septal defect, pulmonary stenosis and anomalous coronary arteries. Panels ( a , b ) Axial
( a ) and coronal ( b ) CCTA demonstrates the aorta ( black arrow ) arising
anterior and leftward of the main pulmonary artery ( white arrow ).
Pulmonary stenosis is present. On this diastolic image, the open pulmonary valve represents insuffi ciency. The right pulmonary artery demon-
strates poststenotic dilatation ( double white arrows on a ). Panel ( c ) 3-D
volume rendered CCTA views demonstrate that the left ( black arrow )
and right ( white arrow ) coronary arteries arise from the most anterior
cusp of the aorta and follow their respective morphologic ventricles. Ao
aorta, PV pulmonary valve, RPA right pulmonary artery (Reprinted
from Shinbane et al. [ 56 ] with permission from SAGE Publications)
abc
Fig. 22.23 CCTA demonstration of a tubular patent ductus arteriosus
measuring 2.2 cm in length arising from a prominent aortic ductus
diverticulum and communicating with the superior portion of the main
pulmonary artery ( arrow ). Given the size and characteristics, a percuta-
neous ductal occluder device closure rather than surgical closure was
performed. Panel ( a ) A 3-D reconstruction in context of skeletal struc-
tures. Panel ( b ) A 3-D reconstruction with skeletal structures removed.
Panel ( c ) A 3-D reconstruction with editing plane demonstrating the
lumen of the patent ductus arteriosus
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