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43
Cannulation strategies ofthe aorta
forcoronarysurgery
Sajjad Raza, Khaled Shorbaji, Salil V. Deo, and Joseph F. Sabik, III
Introduction
Coronary artery bypass graing (CABG) is one of the most commonly performed surgeries in the United States and worldwide. It
can be performed with or without the use of cardiopulmonary bypass (referred to as on- pump or o- pump CABG, respectively). For
most patients undergoing CABG, the on- pump approach remains
the default option. In this chapter, we will describe the technique of
aortic cannulation in patients undergoing on- pump CABG.
Aorticcannulation
e median sternotomy is the primary approach for most patients
undergoing coronary surgery. In patients with favourable body habitus, a full sternotomy can be performed through a skin incision
limited to 12– 18cm. Once pericardiotomy has been performed, inspection of the great vessels and heart is done. e ascending aorta
can be elevated from the surgical eld using strategically placed
pericardial retraction sutures. e length of the ascending aorta
should be examined prior to deciding the location of cannulation.
We believe that the distal ascending aorta is safest for cannulation.
Prior to cannulation, it is important to identify the tentative location
for the cardioplegia needle, aortic cross- clamping, and proximal
anastomoses of the bypass gras.
It is good practice to routinely palpate the aorta to identify obvious
calcied areas. While doing so, it is important to reduce the mean arterial pressure to 55– 60mmHg because a tense aorta can feel sti
throughout. Some centres routinely perform epiaortic ultrasound
scanning (EAS) to detect any so atheroma in the aortic lumen. We
highly recommend its use in patients undergoing CABG. It has a
classIIa recommendation (with level of evidence C) in the current
European Society of Cardiology/ European Association for Cardiooracic Surgery guidelines and a classIIa recommendation (with
level of evidence B) in the current American College of Cardiology
Foundation/ American Heart Association guidelines.
e aortic cannula is inserted between two generously placed
purse- string sutures which are passed within snares. While not
mandatory, in the elderly or in reoperative cases, so felt pledgets
can be used to supplement the sutures. While placing purse- strings
sutures on the ascending aorta it is important to ensure that the
adventitia is included in the sutures. Floating subepicardial bites
can oen lead to dicult- to- control bleeding on cannula removal.
Appropriate blood pressure control (systolic blood pressure of 80–
100mmHg) is very important during aortic cannulation to prevent
bleeding and to reduce the risk of aortic dissection. e epicardium
is then slit between purse- strings, a deliberate full- thickness incision is made within the purse- string sutures, and the cannula is inserted. In case of a right- angled aortic cannula, it is imperative that
surgeons direct the cannula towards the arch. Once the cannula is
inserted, it is important to bleed back the cannula and look for ow
and briskness. Aer connecting the tubing to the cannula in an airfree manner, the perfusionist should conrm that the column swing
is good, the arterial line pressure is within normal limits, and a test
transfusion into the cannula can be done without any increased
pressure (Fig. 43.1).
Aer the patient is successfully weaned from cardiopulmonary
bypass, the aortic cannula is removed, and purse- string sutures are
tied down. While not essential, a third full- thickness stitch can be
inserted to further reinforce the cannulation site. Repair stitches
should include epicardium. Pledgets of felt or prepared in situ from
the patient’s own pericardium can also be used to reinforce the
cannulation area. When the aorta is especially friable, it is good
practice to remove the aortic cannula under low pressure (systolic
blood pressure <80mmHg) once the test dose of protamine is administered. e arterial tubing can be connected to the venous
cannula and blood from the cardiopulmonary bypass circuit can
be returned to the venous side while the remaining protamine
is given.
e main advantages of central aortic cannulation are that
antegrade perfusion is achieved and only a short time is needed
to establish CPB. However, potential complications may include
inability to introduce the cannula, atheroemboli detachment, air
embolism by the cannula, injury to the posterior wall of the aorta,
bleeding around the cannula, abnormal cerebral perfusion, and
aortic dissection.
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Cardioplegia
cannulation
(antegrade)
Cardioplegia
cannulation
(retrograde)
Venous cannulation
(bicaval cannulation)
Arterial cannulation
Fig.43.1 Drawing showing several routes of cannulation:arterial cannulation of the distal portion of the ascending aorta, antegrade cardioplegia
cannulation, retrograde cardioplegia cannulation, and bicaval venous cannulation. IVC, cannula into inferior vena cava; SVC, cannula into superior
vena cava.
Management ofaorticdissection
Aortic dissection is a very infrequent but particularly devastating
complication of aortic cannulation. While the cardioplegia needle tack
vent or proximal anastomoses may be the location for development of
aortic dissection aer the patient is weaned from the heart– lung machine, dissection caused during cannulation can be especially treacherous. Signs of dissection include dicult to control peri- cannula
bleeding, purplish discoloration of the aorta around the cannula, and
low non- pulsatile return of blood from the cannula prior to connection to the tubing. Transoesophageal ultrasound can conrm the split
in the aortic wall. If dissection is suspected, it is critical not to initiate
to ensure safe cardiopulmonary bypass. If, for any reason, a smaller
than recommended cannula is required, the surgeon should refer
to the manufacturer’s manual regarding cannula size and predicted
ow rates prior to selecting the cannula as a right- angled cannula
may lead to increased shear stress.
e arterial cannula is normally the narrowest part of the circuit.
High pressure in a narrow cannula can lead to turbulence (increased
shear stress leads to increased damage to blood cells), localized high
force on the aortic wall with cavitation/ particle embolization (‘sandblasting’), and preferential streaming of ow with relative areas of
hypoperfusion. Pressure gradients at the arterial end should be less
than 100mmHg.,
cardiopulmonary bypass; rather, cannulate either the right axillary artery or the femoral artery and use these vessels for inow.,
If the aortic dissection is localized to the ascending aorta, then
General pearls andpitfalls
replacement of the dissected aorta with a straight Dacron® tube gra
can resolve the problem. However, iatrogenic aortic dissection is still
associated with poor postoperative outcomes and greatly increases
1. Before surgery, it is important to be familiar with the patient’s
aortic anatomy, particularly in high- risk patients. Apreoperative
the mortality and morbidity of an otherwise relatively routine surgical procedure.
Arterialcannulae
Arterial cannulae for central cannulation are primarily right- angled
or straight (Fig. 43.2 and Fig. 43.3). Some have a ange that prevents inadvertent deep insertion of the cannula within the aorta.
Most straight cannulae are scaled to allow the surgeon to know the
length of the cannula within the aorta. Cannula size is selected according to the patient’s body surface area and ow rates necessary
Fig.43.2 Conventional arterial cannulas. (a)Bevel- tipped tapered ‘blue
line’ Texas Heart Institute (THI)- type cannula with moulded flange near
tip. (b)Similar cannula without a flange (‘Bardic’ type) that also can be
used for femoral arterial cannulation.
43 Cannulation strategies ofthe aorta forcoronarysurgery 321
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)
Fig.43.3 Newer arterial cannulas. (a)Metal- tipped right- angled cannula with plastic moulded flange for securing cannula to aorta. (b)Similar design
but with a plastic right- angle tip and moulded flange. (c)(Left) Diffusion- tipped angled cannula designed to direct systemic flow in four directions to
avoid a ‘jetting effect’ that may occur with conventional single- lumen arterial cannulas. An inverted cone occludes the tip. (Right) Drawing with arrows
depicts flow patterns. (d)Integral cannula connector and Luer port (for deairing) incorporated into some arterial cannulas; newer arterial cannulas may
contain a self- venting cap (not shown) for removal of air during insertion.
computed tomography scan of the chest can be helpful in patients with aortic stenosis, le main disease, patients undergoing
redo surgery, and for patients in which calcication is suspected
on chest X- ray or le heart catheter.
2. It is important to cannulate the aorta in a non- atheromatous area as
cannulation in an atheromatous area may cause atheroembolism
and a signicantly increased risk of stroke. erefore, assessment of the aorta for atheroma can guide aortic manipulation
strategies (cannulation, clamping, side- biting). While this can
be done through manual palpation, transoesophageal echocardiography, and EAS, EAS has shown clear superiority over
both palpation and transoesophageal echocardiography for
intraoperative evaluation of the aorta. However, despite the evidence demonstrating reduced stroke rates with an EAS- guided
approach, EAS is not yet a ‘standard- of- care’ procedure in CABG
patients with a class IIa recommendation in current guidelines., Nevertheless, we highly recommend EAS as it can rule
out signicant plaque or atheroma, which might alter cannulation and aortic clamping techniques. In the absence of EAS, if an
atheromatous plaque is found on incision, closing the hole and
cannulating the aorta at a dierent site should be considered instead of inserting a cannula through an aortic plaque.
3. Some patients may have atheromatous disease in the transverse
aortic arch. In such patients, high- velocity jets from a short
cannula placed in the ascending aorta may cause tissue erosion
in the aortic arch and disrupt atheromatous plaques causing
embolization ‘sandblasting’. To limit this, a long cannula can be
used to limit this eect to the descending aorta beyond the origins of the cerebral vessels, and therefore minimizing the risk of
embolic stroke.
4. Good blood pressure control during insertion and removal of
the cannula is crucial as cannulation of a tense aorta can result
in arterial dissection or a tear that can rapidly extend beyond
the connes of the purse- string suture. Consequently, prior to
cannulation it is vital to ensure that the patient’s blood pressure
is under control (systolic blood pressure <90mmHg). In case
of a hypertensive aorta, the blood pressure must be lowered before cannulation. Blood pressure can be lowered by a reverse
Trendelenburg position, raising the patient’s head to reduce
venous return to the heart thereby lowering the blood pressure. Pharmacological agents can also be used to control blood
pressure.
5. It is important to ensure a full- thickness stab of the aorta, gentle
cannula insertion, and to conrm the pulsatile back- bleed prior
to connecting to the circuit. With a right- angled cannula, ensure
that position tip is downstream.
6. It is also important to check arterial line pressure and column
swing prior to initiation of cardiopulmonary bypass.
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7. Do not initiate arterial ow with a questionable cannula inser-
tion. Use transoesophageal echocardiography to rule out aortic
dissection. Relocate the cannula elsewhere in the ascending
aorta if no dissection is suspected. If dissection is suspected, use
the axillary or femoral artery for inow purposes.
8. Acentral aortic cannulation for minimally invasive CABG simu-
lates the strategy used in the standard sternotomy approach.
However, its use in minimally invasive CABG is limited by visibility and, consequently, access to the ascending aorta. erefore,
the ideal cannula for aortic cannulation in minimally invasive coronary surgery is one which is easily insertable from a distance, can
be reliably secured to prevent dislodgment, is safely removable,
and with an in- built mechanism to seal the site of cannulation.
9. Porcelain aorta is a major risk factor for perioperative
atheroembolism and stroke. In patients with porcelain aorta,
ideally an o- pump no- touch aortic technique should be employed to minimize the risk of stroke. However, if on- pump
surgery is preferred, then minimal manipulation of the aorta is
required and axillary artery cannulation can be considered.
REFERENCES
1. Bakaeen FG, Sabik JF. Tailoring operations to the patient is always
best. Circulation. 2016;134(17):1221– 3.
2. Ikram A, Mohiuddin H, Zia A, Siddiqui HU, Javadikasgari H,
Koprivanac M, etal. Does epiaortic ultrasound screening reduce
perioperative stroke in patients undergoing coronary surgery?
Atopical review. J Clin Neurosci. 2018;50:30– 4.
3. Neumann FJ, Sousa- Uva M, Ahlsson A, Alfonso F, Banning AP,
Benedetto U, etal. 2018 ESC/ EACTS Guidelines on myocardial
revascularization. Eur Heart J. 2019;40(2):87– 165.
4. Hillis LD, Smith PK, Anderson JL, Bittl JA, Bridges CR, Byrne
JG, etal. 2011 ACCF/ AHA guideline for coronary artery bypass
gra surgery:a report of the American College of Cardiology
Foundation/ American Heart Association Task Force on Practice
Guidelines. Circulation. 2011;124(23):e652– 735.
5. Abe T, Usui A. e cannulation strategy in surgery for acute type
Adissection. Gen orac Cardiovasc Surg. 2017;65(1):1– 9.
6. Magner JB. Complications of aortic cannulation for open- heart
surgery. orax. 1971;26(2):172– 3.
7. Hwang HY, Jeong DS, Kim KH, Kim KB, Ahn H. Iatrogenic type
Aaortic dissection during cardiac surgery. Interact Cardiovasc
orac Surg. 2010;10(6):896– 9.
8. Neri E, Massetti M, Capannini G, Carone E, Tucci E, Diciolla
F, etal. Axillary artery cannulation in type Aaortic dissection
operations. J orac Cardiovasc Surg. 1999;118(2):324– 9.
9. Singh A, Mehta Y. Intraoperative aortic dissection. Ann Card
Anaesth. 2015;18(4):537– 42.
10. Drews JA, Cleveland RJ, Nelson RJ. An approach to aortic
cannulation with a caution on hemolysis associated with angled
cannulas. Rev Surg. 1974;31(1):57– 9.
11. Brodman R, Siegel H, Lesser M, Frater R. A comparison of ow
gradients across disposable arterial perfusion cannulas. Ann
orac Surg. 1985;39(3):225– 33.
12. Galletti PM, Brecher GA. Heart– lung bypass. NewYork:Grune &
Stratton, 1962.
13. Grossi EA, Kanchuger MS, Schwartz DS, McLoughlin DE,
LeBoutillier M, 3rd, Ribakove GH, etal. Eect of cannula length
on aortic arch ow:protection of the atheromatous aortic arch.
Ann orac Surg. 1995;59(3):710– 2.
14. Bittner HB, Savitt MA, Ching PV, Ward HB. O- pump coronary
artery revascularization:ideal indication for patients with
porcelain aorta and calcication of great vessels. J Cardiovasc
Surg (Torino). 2003;44(2):217– 21.
15. Sabik, JF, Lytle BW, McCarthy PM, Cosgrove DM. Axillary
artery:an alternative site of arterial cannulation for patients
with extensive aortic and peripheral vascular disease. J orac
Cardiovasc Surg. 1995;109(5):885– 90.
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44
How toperform a distal coronary
anastomosis
David Glineur and Juan B. Grau
Introduction
e purpose of this chapter is to describe in detail the technical nuances and planning necessary to construct high- quality, long- lasting
anastomoses during coronary artery bypass graing. Issues to be
covered include suture selection, needle manipulation techniques,
correct exposure of the coronary target, and various types of anastomoses. ese recommendations are intended to support and guide,
rather than to dictate one or another approach, as every surgeon will
develop their own preferred techniques. Here we have attempted to
summarize the technical approaches of two cardiothoracic surgeons
from dierent academic backgrounds and training programmes
who have developed their practices on two dierent continents.
Modication of these recommendations is not only permitted but
encouraged, as long as the fundamental principles of spatial proportion, quality, and sound technique are preserved.
Suturematerial
e most common types of suture materials used for coronary
anastomoses are monolament and braided. e monolament
is most oen used as a running suture line, whereas the braided
material is preferred by some surgeons when an interrupted technique is performed. e size of the suture varies from 8- 0 to 7- 0
depending on surgeon preference. For multiple sequential anastomoses with arterial gras, we consistently use 8- 0 monolament
suture.
Preparation ofthe coronarytarget
e creation of a good anastomosis starts long before any suturing
is being considered, when the native coronary artery is exposed.
Mistakes at this juncture will have a signicant impact not only
throughout the construction of the anastomosis itself but also on
long- term gra patency.
e initial arteriotomy into the coronary artery is performed with
a no.15 blade or a ne beaver blade in order to incise all the tissue
layers over the anterior aspect of the artery allowing for optimal exposure of the coronary target. In many instances, the placement of
two 5- 0 exposure sutures on each side of the planned coronary target
is recommended to retract the fat and epicardial muscle surrounding
the coronary arteriotomy site. is is particularly important in the
case of an intramyocardial coronary artery, wherein the muscular
edges of the epicardium and myocardium surrounding the site of
the anastomosis must be resected or cauterized in order to avoid
constructing the anastomosis at a deeper plane than the epicardium.
e non- adherence to this recommendation may cause what has
been called ‘the seagull eect’ which is particularly common when
sequential graing is used.
Preparation ofthe graftconduit
A minimal- or no- touch technique is recommended for atraumatic
preparation of the conduit, to maintain the integrity of the endothelium, which is the only regulating barrier against thrombosis
formation. is is especially important for arterial gras, where the
endothelium regulates the production of factors such as endothelialderived relaxing factors including nitric oxide, among others. ese
factors have signicant vasomodulating properties that help control
the vasomotor tone of the arterial gra, and thereby regulate the
blood ow through the gra.
When planning the actual construction of the anastomosis, it is
paramount to strategize the placement of the sutures from the inside
of the coronary artery to the outside to prevent the dislodgement of
atheromatous plaques that could cause coronary artery embolism
or occlusion. is method of suture placement allows for the inclusion of the plaque into the running suture line and helps to prevent
any disturbance of atheromatous plaque that may be present at the
anastomotic site.
Here there are a few technical recommendations that, although
oen not routinely addressed, make for a reproducible and safe
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approach to the construction of all dierent types of coronary
anastomoses:
• e surgeon must always use both hands to avoid placing tension
dg
on the walls of the coronary arteriotomy or the free edges of the
gra conduits. It should be appreciated that in many instances the
non- dominant hand is underutilized and can be of great assist-
cg
ag
bg
ance for exposure during coronary surgery.
• e needle should always be prepared and loaded for the next su-
ture near the site of the anastomosis. Pulling the needle outside of
the mediastinum for hand loading onto the needle holder is not
recommended. is is particularly important when working in a
cc
bc
ac
dc
small space such as the lateral wall of the heart when an o- pump
procedure is performed. Keeping needle manipulation near the
anastomosis facilitates the work eciency and avoids problems.
Fig.44.1 T anastomosis.
• e needle should not only be used at 45° or 90° of angulation
with the needle holder, but rather utilizing all 360° of the axis of
the needle holder. is facilitates the optimal angulation for every
suture bite, and allows the needle to be positioned at a 90° angle
from the coronary artery at all times. An example of this is the
hook position when tackling the heel or toe of any anastomosis.
• When using a running suture line, the parachute technique al-
lows the surgeon to have an unobstructed view of all stitches while
avoiding unnecessary stress on the wall of the coronary artery and
providing more consistent suture spacing.
• When the anastomosis is completed, it is preferable to tie on the
lateral wall of the anastomosis. Tying at the heel or the toe should
be avoided at all times.
• Before tying the suture it is preferable to ll the gra with either
blood or Plasma- Lyte® to avoid any purse- string eect and narrowing of the anastomosis.
• Whenever possible, nish the suture line of a given anastomosis
on the side closest to the operating surgeon.
conduit. is creates gra distortion and turbulent ow, which are
both undesirable.
We will describe all four types of coronary anastomoses independently, aided by drawings. Additional explanations are provided
for the more technically challenging anastomoses.
Classical termino- lateralanastomosis
For a classical termino- lateral anastomosis where both gra and coronary arteriotomy are parallel to each other, the length of the free
end of the gra incision should be approximately 25% larger than
the coronary arteriotomy. Careful spacing and the avoidance of any
twisting are crucial (Fig.40.1).
Termino- lateral ‘T’anastomosis
For a 90° termino- lateral or ‘T’ anastomosis, the size of the coronary arteriotomy must be smaller than the free end of the gra
to avoid attening the anastomosis. In this type of anastomosis,
the coronary arteriotomy should be divided into anterior and posterior. e posterior section will correspond to the heel of the gra
The openings inthe coronary artery and
graftconduit
ere are a number of dierent types of coronary artery anastomoses, all of which must be completed with careful attention to angles, dimensions, and proportions of both the gra conduit and the
coronary arteriotomy. Fundamentally, anastomoses can be divided
into two categories (lateral- lateral anastomoses and terminal- lateral
anastomoses) and dierent congurations based upon the angle at
which the gra conduit and the coronary arteriotomy meet (90° vs
180°). e 180° anastomoses, by their very nature, are more straightforward from a technical perspective due to their complementary
shape. However, 90° anastomoses demand careful reconguration
of the opening in the gra conduit to precisely match the anterior
and posterior aspects of the coronary arteriotomy using a diamondshaped approach.
In all types of anastomoses, the opening of the gra must be at
least 25% larger than the opening on the coronary side. is surplus
of tissue facilitates a cobra- head shape at the hood of the gra conduit, which allows an optimal ow pattern. Failure to adhere to this
recommendation may result in a attened anastomosis, in which the
gra is placed under tension due to an insucient distal end of the
conduit, and the anterior will correspond to the toe. For the righthanded surgeon, the rst suture should be placed at the 3 o’clock
position on the gra side and then through the far right end of the
coronary arteriotomy. Suturing will then progress clockwise across
the heel of the gra to complete the posterior half of the anastomosis. Having completed the rst half of the anastomosis at the
far le of the coronary arteriotomy, the surgeon will then continue
across the anterior aspect of the anastomosis, terminating at the
point of origin. Again, careful attention to twisting and spacing is
required (Fig. 40.2).
Latero- lateral anastomosis:180°
For a latero- lateral anastomosis, the length of the gra incision
should be greater than the length of coronary incision to obtain
a nice bulging anastomosis. e depth of the sutures, in this particular instance, is important, to avoid kinking of the gra conduit
(Fig. 40.3).
Latero- lateral anastomosis:90° (diamond- shaped)
For a diamond- shape anastomosis (criss- cross anastomosis), the
size of the coronary arteriotomy should be smaller than the perimeter of the gra to avoid a at anastomosis. e size of the gra
incision should be larger than the size of the coronary incision. In
44 How toperform a distal coronary anastomosis 325
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b
a
dg
cg
bg
bc
cc ac
dc
ag
Fig.44.4 Diamond shape or criss cross anastomosis.
Fig.44.2 Termino-lateral anastomosis.
anastomosis, starting at the 3 o’clock position. When sequential graing is being considered, if proximal in- ow of the gra
is present, this will be the rst anastomosis to be constructed. If
proximal in- ow is not yet available, this will be the last distal
anastomosis constructed, before the proximal anastomosis is constructed (Fig. 40.4).
Conclusion
In order to adequately treat patients with coronary artery disease,
today’s cardiothoracic surgeon must have a strong technical foundation and clear understanding of the nuances of surgical coronary
Fig.44.3 Latero-lateral anastomosis.
revascularization. is includes dierent types of gras, dierent
gra congurations, and anastomotic techniques, including those
described in this chapter. Adherence to our recommendations will
this type of anastomosis, the coronary arteriotomy should be divided into two sections, posterior and anterior, as was done for the
facilitate the adoption of increasingly complex techniques for coronary revascularizations by most surgeons.
termino- lateral 90° ‘T’ anastomosis. In this situation, posterior
and anterior segments of both gra and coronary arteriotomy
need to be matched in length by careful placement of properly
Acknowledgements
spaced sutures. e surgeon must ensure that the circumference
of the gra is larger than the coronary arteriotomy. e suturing
technique is exactly as described for the termino- lateral 90° ‘T’
We would like to thank Mrs Jacqueline Fortier for help in writing the
manuscript and Mrs Paloma Grau for the illustrations.
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45
Compositegras
James Tatoulis and Brian F. Buxton
Introduction
Composite gras should be within the repertoire of every coronary
surgeon. Validated in the early 1990s, they are used to accomplish
multiple or total arterial revascularization, which achieves the best
coronary revascularization results, either with two internal thoracic arteries (ITAs) or by a combination of an ITA and a radial
artery (RA).
Routine use:left/ right internal thoracic
artery Y- or T- graft
Bilateral ITA graing is most frequently achieved by a composite
le/ right internal thoracic artery (LITA/ RITA) arrangement of the
two best coronary conduits, either on- or o- pump, through one incision without gras crossing the midline. Manipulation of the ascending aorta is avoided to reduce the risk of stroke. Pedicled or
skeletonized ITA gras can be used. Skeletonized ITAs allow maximum dilatation, length, and versatility, while minimizing chest wall
trauma and sternal infection.
e construction of the LITA/ RITA Y- or T- anastomosis is
critical, but no more complex than a LITA to le anterior descending artery (LAD) anastomosis that coronary surgeons perform daily.
Spasm prophylaxis is essential and achieved with topical vasodilators. e Y- (or T- ) anastomosis is formed aer heparinization,
but prior to cardiopulmonary bypass. Asupercial stable, immobile
platform is created by placing a pack between the sternal edges, well
anterior to the aorta. e anastomosis is constructed at the level of
the base of the le atrial appendage or pulmonary valve to ensure
the best and most direct lie. e length of the LITA above the anastomosis should be carefully judged with the heart full, and normal
lung ventilation, to ensure adequate, but not redundant length.
Redundancy may lead to kinking of the proximal LITA trunk. e
Y/ T- anastomosis can be constructed on the anterior, le lateral, or
posterior aspect of the LITA with equally good results; hence, it is a
matter of personal comfort. We perform the anastomosis on the anterior aspect of the LITA (between the second and third intercostal
branches) (Fig. 45.1a).
e LITA is proximally controlled with a so bulldog clamp. All
fascia is removed from the site of anastomosis as even small, imsy
fascial bands may distort the anastomosis. e LITA is stabilized
by attaching loose fascia/ fat on either side, to the pack with small
vascular clips.
A 6– 8 mm longitudinal incision is made with an ophthalmic
blade, and the proximal end of the RITA is shaped and splayed vertically, 10– 20% longer than the LITA arteriotomy. e anastomosis
is constructed with a continuous 7- 0 or 8- 0 polypropylene suture
with a 7mm, 3/ 8 circle needle. We commence at the superior end
of the LITA arteriotomy and run the suture line forehand down the
right- hand side inferiorly to the heel, and for one or two bites back
up the le- hand side. At the heel, either arteriotomy can be extended
to ensure an accurate match (Fig. 45.1b, c).
e anastomosis is completed by running the second limb of the
suture, forehand, along the le- hand side (Fig. 45.1d). e bulldog
clamp is released prior to tying the suture to allow maximum anastomotic dilatation and to avoid ‘purse- stringing’. Size 7- 0 polypropylene adventitial sutures are placed inferior to the anastomosis to
minimize any tension or distortion, and to orientate the RITA limb
correctly.
For a T- anastomosis, the LITA arteriotomy is shorter (5– 6mm).
e proximal RITA is transected directly across, and the underside
is incised only 3– 4mm to allow a good size match for the T position
at 90° to the LITA. In this setting, the suture line can be completed
as described previously or, alternatively, commence at the heel of the
RITA, running forehand to the inferior aspect of the anastomosis,
then forehand superiorly to the apex, and nally continuing forehand along the LITA until the other suture limb is met. e ow out
of each limb should be objectively measured.
is technique allows the surgeon to work towards oneself, ensures the assistant does not get in the way, and allows tailoring of the
LITA arteriotomy or the RITA hood to the correct length. However,
surgeons should use whatever anastomotic technique they prefer.
We temporarily secure the LITA limb to the epicardium over the
pulmonary trunk, to ensure the LITA limb stays in position during
the construction of the distal anastomoses— to avoid tension and
ensure correct conduit length between anastomoses.
e LITA limb is anastomosed to the LAD. Asequential anastomosis to the diagonal is reasonable if it warrants graing, providing
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