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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3597_Библиотеки_им_академика_М_И_Перельмана
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when this vessel has been used as an arterial bypass graft (typically
to the RCA). Use of the right radial approach permits easiest canalization of the RIMA, whereas the femoral approach can be challenging,
especially in an older patient with an elongated aorta (type-III aortic
arch). From the femoral approach, the innominate must be engaged
using an IM catheter in the LAO projection followed by advancing a
J-wire into the subclavian artery (Fig. 3-9, D). Care must be taken not
to wire the right common carotid, which is the other major branch of
the innominate. Engagement of the RIMA can be performed in AP
projection or LAO. Head positioning or caudal arm movement sometimes assists in selective RIMA intubation.
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Coronary Angiography and Ventriculography 113
Saphenous Graft Angiography
Locating saphenous vein graft (SVG) ostia can be challenging.
Sometimes, surgeons place graft markers (clips or rings) near the
SVG ostium, permitting easier future angiography. Unfortunately,
the markers may not be exactly at the graft opening. Most of the
time, surgeons forego markers. Classically, the orientation of SVGs
from lowest (caudal) to highest (cranial) has been RCA, LAD, diagonals (branch of LAD), and then obtuse marginal (a branch of
the CFX).
Coronary artery SVGs are visualized in at least two views (LAO
and RAO). It is important to show the aortic anastomosis, body of the
graft, distal anastomosis (Fig. 3-10), distal runoff, and collateral chan-
nels. The optimal view of graft-vessel anastomosis is usually seen in
the view that depicts the native vessel best. Stumps of occluded SVGs
should be recorded for future reference.
General Strategy for Coronary Artery
Bypass Graft Angiography
Following native LCA and RCA angiography and visualization of
missing or reciprocally filled vessel segments, the operator proceeds
to SVG angiography using key views for specific coronary artery segments and taking into account the subsequent need to determine
contingency views or addition of special views.
A. SVG to RCA (lowest): This graft is best engaged in an LAO projec-
tion and travels downward, paralleling the RCA. It can be easily
cannulated with a multipurpose (MP) catheter or Judkins right (JR)
catheter. Other catheters useful for this type of graft include a right
coronary bypass (RCB) graft catheter or an Amplatz right modified
(AR mod) catheter. The best views for these grafts are LAO cranial,
RAO, and AP cranial.
B. SVG to LAD (second lowest, above RCA): The LAD SVG graft typi-
cally originates from the anatomic leftward aspect of the anterior
aorta and is best engaged in RAO using a JR4 (Judkins right, 4 cm),
left coronary bypass (LCB), or Amplatz left (AL) catheter. The best
views for a LAD graft are lateral, RAO cranial, LAO cranial, and AP
(the lateral view is especially useful to visualize the anastomosis to
the LAD).
C. SVG to diagonal: Diagonal SVGs also are best visualized in the
RAO projection and using the same catheters as those used for SVG
to LAD. Often, a slight clockwise rotation from an inferior graft
permits the JR4 to engage this graft. The best views for SVGs to
diagonal are LAO cranial and RAO cranial.
D. SVG to obtuse marginal (highest SVG on the aorta): SVG marginal
grafts are best engaged in RAO projections using a JR4, LCB, or AL
catheter. The best views for an SVG to obtuse marginal are LAO
caudal and RAO caudal.
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Coronary Angiography and Ventriculography
A
Graft
Graft
LCA
RCA
B
Figure 3 -10 A, Usual insertion sites of vein grafts to coronary ar teries.
The proximal (aortic) anastomosis site of the graft to the right coronary
artery (RCA) is most anterior and usually the lowest. Graf ts to the branches
of the left coronary arter y (LCA) usually are inserted in a progressively higher
and more posterolateral position. Variations frequently occur. B, Use of the
Judkins right (JR) and left (JL) vein bypass catheters. For RCA grafts, the
catheter is rotated clockwise in the left anterior oblique (LAO) projection
until the tip is superior to the graf t orifice. It is then advanced down the
aortic wall to the orifice of the graft. C, For LCA grafts, clockwise rotation
is applied in the lef t or right anterior oblique (RAO) projection. (From Tilkian
AG, Daily EK: Cardiovascular procedures: Diagnostic techniques and therapeutic procedures, St Louis, 1986, Mosby.)
RCA
C
LCA
Right Gastroepiploic Artery
Because of the strong patency of arterial grafts, some surgeons graft
the RCA or PDA using the right gastroepiploic artery (GEA). The right
GEA, a branch of the gastroduodenal artery, originates from the
common hepatic artery, which is one of the main three branches from
the celiac trunk. If the operative report is not available, use of this graft
should be considered if median sternotomy extends inferiorly into the
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abdominal cavity or numerous surgical clips extend up from the
abdominal cavity to the inferior wall of the heart. Selective angiography of these grafts requires special technique. It is recommended that
only operators familiar with peripheral anatomy and angiography
perform GEA angiography because it requires knowledge of the vessel
anatomy and selective canalization of the GEA. First, the celiac trunk
(located anterior and inferiorly directed) must be engaged using
specialized peripheral catheters, such as the Cobra (Cook Medical,
Bloomington, IN) or Simmons Sidewinder. Anticoagulation with
heparin or bivalirudin is recommended, given the need for sub-branch
vessel wiring. Once the celiac trunk is engaged, an angioplasty style
wire (typically, 0.018 or 0.014 inches) should be passed through the
common hepatic to the gastroduodenal and then to the GEA using
“roadmap imaging” (see Peripheral vascular disease chapter 5). Over
this wire, a smaller 4-F or 5-F catheter (Terumo straight glide catheter)
or transit catheter (0.035-inch Quickcross [Spectranetics]) can be
advanced to perform selective GEA graft angiography. Care must be
exerted not to cause vessel dissection. The prophylactic administration of nitroglycerin should prevent vessel spasm.
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Coronary Angiography and Ventriculography 115
Contrast Media Injection
Techniques: Power Versus
Hand Injection
Contrast medium, a viscous, iodinated solution used to opacify the
coronary arteries, can be injected either by hand through a multivalve manifold or by a variable rate power injector. For hand injections, flow rates are usually 2 to 4 mL/sec with volumes of 2 to 6 mL
in the RCA and 7 to 10 mL in the LCA. Operators should keep the tip
of the syringe pointed down (handle raised up) so that any small
bubbles float up and are not injected into the circulatory system
(Fig. 3-11). The use of disposable manifolds, syringes, and tubing is
cost effective and safe.
Power injection of contrast media is as safe as hand injections,
with operator-controlled rate and volume injections producing excellent opacification. Coronary power injectors use sterile hand controls,
permitting precise operator touch-sensitive variable volume injectors
(ACIST Medical Systems; Bracco Research USA; Medrad, Inc.), and a
computer touch screen allows precise contrast delivery settings (Fig.
3-12). The system is especially helpful for small-diameter catheters
(<
5 F). In addition, it is also highly cost effective with the large contrast
reservoir. Typical settings for power injections are as follows:
•
RCA: 6 mL at 3 mL/sec; maximal 450 psi
• LCA: 10 mL at 4 mL/sec; maximal 450 psi
Cineangiographic Frame Rates
Images may be acquired at different frame rates but a frame rate of
30 frames/sec is most commonly used. In some pediatric cases or if
the heart rate is greater than 95 beats/min, the rate of 60 frames/sec
may be used. In many adult laboratories, 7.5 to 15 frames/sec is standard and reduces radiation dosage to patient and staff.
Panning Techniques
Most laboratories use x-ray image screen sizes (e.g., 8 inches in diameter or less) that may preclude having the entire coronar y artery
course visualized without panning over the heart to include the late
filling portions of the arterial segments and any collateral filling. In
addition, in most views, some degree of panning is necessary to identify regions that are not seen from the initial setup position. Some
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Coronary Angiography and Ventriculography
Figure 3 -11 Pioneer Dr. Goffredo Gensini performing coronar y angiogra-
phy. Note the raised angle (30 degrees) of the injection syringe to keep out
air bubbles. (From Gensini GG: Coronary angiography, Mount Kisco, NY,
1975, Futura.)
branches may unexpectedly appear later from collateral filling or
other unusual arterial input sources. Imaging runs should be long
enough to see contrast in the cardiac veins, which is generally
long enough to pan to see late-filling collateralized coronary vessels.
Angiographic View Setup Keys
“The best panning is no panning.” Panning motion that is too fast or
overshoots the image targets causes information to be lost. The key to
accurate, optimal coronary cineangiography (that is, obtaining the
most information for the least amount of movement) is the initial setup
of the catheter on the fluoroscope screen. Figure 3-13 shows the
catheter–LM artery setup keys for LAO views in the straight AP, cranial,
and caudally angled projections. When the patient is positioned correctly and the setup key followed, only minimal panning is necessary
to obtain the information. In the LAO view, the operator pans down
the LAD artery then rightward to identify collaterals going to the RCA.
If the CFX is occluded, then leftward panning will include collaterals
going to the distal CFX artery. For the RCA, in the LAO position, the
operator pans downward and to the left toward the LAD artery. This
visualizes late-filling collaterals from the right coronary system to the
LAD artery. These motions are diagrammed in Figure 3-13.
In RAO projections for the LCA and RCA, the operator pans downward to the apex to identify late-filling, left-to-left, or right-to-left
collaterals. The initial setup keys for catheter tip position on the fluoroscope, summarized in Table 3-1, help the operator include all crucial
information for coronary angiography.
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Coronary Angiography and Ventriculography 117
A
B
Figure 3-12
A, Operator touch screen selects injection of coronary arteries or ventriculography. B, Mounted on the injector, a large contrast bottle permits multiple
patient studies because only the hand control and patient injection tubing
are sterile and changed for each patient. The injection syringe with piston
has several valves and bubble detectors used to prevent contamination and
inadver tent air injection.
Power injector (Bracco Research USA, Princeton, NJ).
Collateral Circulation
The opacification of a totally or subtotally (99%) occluded vessel from
antegrade or retrograde filling is defined as collateral filling. The collateral circulation is graded angiographically as follows:
Grade Collateral Appearance
0 No collateral circulation
1 Very weak (ghostlike) reopacification
2 Reopacified segment, less dense than the feeding
3 Reopacified segment as dense as the feeding vessel
vessel, and filling slowly
and filling rapidly
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LAO
LAO
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Coronary Angiography and Ventriculography
LAO
cranial
RAO
Spine
Setup
key
A
LAO
cranial
caudal
Spine
Setup
key
B
Figure 3 -13 Setup keys for panning during coronar y angiography. A, Right
coronary artery (RCA). B, Left coronary artery (LCA). LAO, Left anterior
oblique; RAO, right anterior oblique.
It is useful but difficult to establish the exact size of the recipient
vessel. The operator determines whether the collateral circulation is
ipsilateral (e.g., same-side filling, proximal RCA to distal RCA collateral
supply) or contralateral (e.g., opposite-side filling, LAD artery to distal
RCA collateral supply) and identifies exactly which region is affected
by collateral supply and stenoses in the artery feeding the collateral artery. He or she notes whether the opacification is forward
(anterograde) or backward (retrograde). This evaluation is important
for making decisions regarding which vessels might be protected or
lost during coronar y angioplasty.
Usefulness of Biplane Coronary Angiography
Simultaneous biplane cineangiography, although uncommonly used,
provides accurate images from two different simultaneous points of
1 2 3
4 5 6
7 8 9
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Coronary Angiography and Ventriculography 119
LCA RCA
Lateral
Spine
Setup
key
C
Figure 3-13, cont’d
coronary arter y.
Table 3 -1
Setup Key Locations for Angiographic Views
Artery View
LAD LAO cranial 2 Setup on screen
RCA LAO cranial/caudal 1, 2 Lef t upper coronar y
LAD/RCA AP Cr anial 2
C, Lateral views. LCA, Lef t coronar y artery; RCA, right
Setup Region on
Angulation Grid
(below)* (No.) Comment
LAO caudal 5 Top, midline
RAO cranial 1 Top, lef t upper
coronary
RAO caudal 4 Middle, lef t side
RAO cranial/caudal 1, 4 Left upper coronary
For either LAD or RCA (L AD/RCA) in AP, cranial angulation, use position 2.
AP, Anterior-p osterior; LAD, left anterior descending; LAO, left anter ior oblique; RAO,
right anterior oblique; RCA, right coronary arter y.
*Fluroscreen grid.
The rectangle of the TV monitor showing t he position of the catheter tip c an be
divide d into a g rid of nine boxes. The position on the screen shown by the number
below can be use d to position the beginning point of th e imaging run.
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view and is advantageous in performing complete coronar y or ventriculography with reduced contrast volumes and radiation exposure.
Biplane angiography is most useful for the pediatric population and
those patients with need for reduced contrast load (e.g., patients with
renal failure).
difficulty of use. The traditional biplane coronary angiography setup
required the patient’s heart to be in the exact center of the two planes
(the isocenter) and then the AP and lateral planes were rotated from
vertical or horizontal to orthogonal projections (i.e., perpendicular
imaging planes, LAO cranial, and RAO caudal [Fig. 3-14]). This setup
often resulted in more difficulties than it solved, in that panning in one
plane moved the heart out of the field of the other plane. Alternatively,
setting up the biplane using concordant imaging views (i.e., with both
C-arms in the same direction), such as using cranially angled LAO and
RAO projections and then moving both C-arms to caudally angled LAO
and RAO projections (see Fig. 3-14), makes biplane angiography
simple, quick, and effective. In this way, angiographic information is
not lost when panning because the heart moves in a similar direction,
albeit from the opposite side (but not cranial vs. caudal). With the
concordant biplane setup, contrast use is halved, radiation dose
reduced, and procedure time shortened. Although biplane coronary
angiography is not generally considered critical for routine studies, if
the laboratory has biplane capability, this form of angiography can
improve procedure times, contrast use, and information quality.
Coronary Angiography and Ventriculography
The value of biplane information must be balanced against the
Rotational Coronary Angiography
To avoid radiation exposure and reduce consumption of contrast dye,
some institutions use rotation of the C-arm during coronary angiography. Rotational coronar y angiography has been established for noncoronary angiographic procedures, particularly in the diagnosis and
treatment of cerebrovascular disease. However, the use of rotational
coronary angiography is just emerging as a valued clinical practice.
Coronary Angiographic Catheters
The femoral arterial catheterization technique initially performed by
Dr. Melvin Judkins continues to bear his name and has been highly
successful because of its simplicity and ease of use with preshaped
catheters (Fig. 3-15). As discussed earlier, operators using the radial
artery for access can use a different array of specially designed catheters. Regardless of the vascular access, all catheters are inserted with
a J-tipped guidewire. This J-wire is advanced into the ascending thoracic aorta under fluoroscopic guidance. The catheter follows the
guidewire to the central position. When the catheter tip has reached
the desired location in the aorta, the guidewire is removed and the
catheter is aspirated (2 to 3 mL of blood), flushed, and connected to
the pressure manifold. The guidewire or catheter tip should always be
visible on the fluoroscopy screen when the catheter or guidewire is
manipulated.
Judkins-Type Coronary Catheters
Judkins catheters have preshaped curves and tapered end-hole tips.
The Judkins left (JL) coronary catheter has a double curve. The length
of the segment between the primar y and secondar y curve determines
the size of the catheter (i.e., 3.5, 4, 5, or 6 cm). The proper size of the
JL catheter is selected depending on the length and width of the
ascending aorta. In a small person with a small aorta, a 3.5-cm catheter is appropriate, whereas in a large person or in an individual with
an enlarged or dilated ascending aorta (e.g., as a result of aortic stenosis, regurgitation, or Marfan syndrome), a 5- or 6-cm catheter may
be required (Fig. 3-16).
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LAT
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Coronary Angiography and Ventriculography 121
A
AP 30 degrees caudal 45 degrees LAO
B
LAT 30 degrees cranial 45 degrees RAO
AP-LAT 90 degrees
C
Figure 3-14
A, Biplane C-arms in perpendicular anterior-posterior (AP) and lateral starting configuration. B, Biplane C-arms rotated in opposing cranial/caudal,
left anterior oblique/right anterior oblique (LAO/RAO) angulations. Panning
in one plane moves the heart out of the other plane. C, Biplane C -arms
rotated in a concordant cranial orientation. Panning keeps images visible
on both screens. LAT, Lateral.
AP 30 degrees cranial 45 degrees LAO
LAT 30 degrees cranial 45 degrees RAO
Diagrams of biplane angiographic C-arm orientations.
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Coronary Angiography and Ventriculography
Curve style A
2.5-inch tip
Curve style B
1-inch tip
Sones Judkins
Left
I
Right
II
Coronary vein
bypass
graft catheter
A
El Gamal
Internal mammary
catheter
145°
Pigtail
ventriculography
catheter
Type I
Type II
Type III
Castillo
Right I
Right II
Left I
Left II
Amplatz
Schoonmaker
B
Figure 3-15 A, Coronary angiographic catheter shapes. B, Preformed
catheters for radial approach: Radial TIG 4.0, Sarah Radial, Jacky Radial.
The ingenious design of the JL catheter permits cannulation of
the LCA without any major catheter manipulation. The catheter tip
follows the ascending aortic border and falls into the LM coronary
ostium, often with an abrupt jump. In the words of its inventor, from
the femoral approach “the [Judkins] catheter knows where to go if not
thwarted by the operator.” Because of the ease of seating in most
patients, the slow advance of the catheter under fluoroscopic control
will prevent rapid engagement into an unexpected LM narrowing.
A JL4 catheter fits most adults with the catheter tip aligned parallel with the long axis of the LM coronar y trunk. A smaller (3.5 cm)
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