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[12]. To simplify aortic valve–sparing operations, several techniques have been described, such as Florida sleeve repair
[13], Corset technique [14], and (personalized external aortic root support) PEARS application [15].
INDICATIONS FOR AORTIC ROOT SURGERY
ARR indications differ (Table 26.1), but the selection of the optimal surgical approach is more complicated. The goal of
these procedures is patient survival and prevention of late complications. The aneurysmal dilatation of the aortic root in
congenital disorders (annuloaortic ectasia and bicuspid aortic valve) or in chronic aortic dissection is the most common
indication for the ARR [16,17]. Sinus of Valsalva aneurysm (SVA) can be complicated with an aortocardiac fistulae, and
ARR is the essential option to correct this pathology [18]. Complicated aortic valve endocarditis with periannular abscess
and/or fistulization into the adjacent cardiac chambers sometimes requires lifesaving ARR [19]. Root replacement remains
the only option for extremely calcified ascending aortas with existing aortic valve pathologies [20]. ARR would also be
the appropriate surgical solution for the patient with a narrow aortic root [21]. Finally, patients with congenital cardiac
anomalies may require ARR in their lifetime because of the progressive root and ascending aorta dilatation that often occurs
before (conotruncal abnormalities) or after (Ross, arterial switch) surgical correction [22].
INITIAL STAGES
Conventional open-heart surgery is the essential procedure for isolated ARR. Urgent surgery is usually preferred for lifethreatening pathologies of the aortic root, and standard approaches should initially be used for emergent situations or with
concomitant cardiac procedures. Some more recent approaches toward more noninvasive surgery can be considered in elective, noncomplicated isolated aortic root surgery. These minimal invasive approaches begin with anesthesia and end with
surgical techniques with the goal toward reducing the adverse effects of open-heart surgery.
Anesthesia
General Anesthesia
General anesthesia is the standard approach for aortic root surgery. The goal is to reduce stress immediately and to maintain
stable hemodynamics during surgery. The most important risk for patients with aortic root pathology is sympathetic activation, which causes hypertension, tachycardia, and respiratory distress resulting in unexpected lethal aortic complications.
Full hemodynamic monitoring should be implemented during all procedures, and transesophageal echocardiography is
indispensable, especially in cases of aortic valve–sparing procedures.
High Thoracic Epidural Anesthesia
To minimize the side effects of general anesthesia, awake open-heart surgery has been offered as a new and unique approach
in coronary artery bypass surgery [23]. Awake on-pump cardiac surgery offers several advantages over general anesthesia,
including absence of tracheal intubation, reduced stress response, lower postoperative arrhythmias, and improved pulmonary outcome [24,25]. This approach may be more beneficial and safer than conventional anesthesia in patients with
TABLE 26.1 Indication for Aortic Root Replacement
1. Aortic root enlargements (dilatation, aneurysm, and pseudoaneurysm)
2. Sinus of Valsalva aneurysms with/without cardiac fistulae
3. Aortic root dissection
4. Aortic root destructive endocarditis (abscess)
5. Heavy calcified aortic valve and aortic root
6. Small aortic root (ineffective aortic root enlargement)
7. Supra-aortic stenosis
8. Aortic root reoperations
9. Congenital diseases
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chronic obstructive pulmonary disease who are frequently rejected for cardiac surgery [26]. Using this approach with ministernotomy techniques may result in outcomes that are better than standard full-median sternotomy [27]. This approach
should be only used in elective cases with noncomplicated aortic root surgery, whereas general anesthesia remains the
preferred option in aortic valve–sparing procedures or in emergency situations, especially aortic dissection.
Sternotomy and Cannulation
Full-Median Sternotomy
After the usual preparations, the standard replacement of the nondissected aortic root begins with the full-median ster-
notomy under general anesthesia. Full-median sternotomy is the versatile and most reliable option to reach all sites of
the heart during open-heart surgery. Full-median sternotomy is typically the first choice of young surgeons and residents,
but minimal invasive incisions may be preferred by experienced surgeons to reduce invasivity and adverse effects of fullmedian sternotomy. Full-median sternotomy can be restricted only to perform aortic root surgery in the presence of other
concomitant cardiac pathologies; otherwise, limited median sternotomy is the best approach for isolated aortic root surgery.
After the usual preparations, standard central arterial cannulation is established through the distal ascending aorta or
the lateral wall of the midaortic arch. If any dissection is present at the ascending aorta, the arterial cannulation should
be performed through a patent peripheral artery such as the right subclavian artery or a noninjured femoral artery [28].
Nonetheless, ascending aortic cannulation has been described even in cases of dissected aortas and aneurysms when peripheral cannulation is impossible [29]. Venous cannulation is prepared using a single, two-staged venous cannula through the
right atrial appendage. Bicaval venous cannulation is needed only in the setting of concomitant valvular procedures, Ross
procedure, fistula from aorta into the right heart chambers or intracardiac defects. A vent cannula is passed through the right
upper pulmonary vein into the left atrium.
Cardiopulmonary bypass is established at 32°C, and the ascending aorta is occluded. Applying the aortic cross-clamp is
one of the major stages of this operation. Aortic cross-clamp distance between the aortic root and arch should be as far as possible for optimal exposure of the aortic root. The ascending aorta above the sinotubular junction (STJ) and pulmonary artery
trunk should be properly divided before cross-clamping so as to place the aortic clamp just proximal to the aortic arch. To
control distal aortic pressure control and to be aware of the possible signs of malperfusion are very important after clamping
the aorta. Hypothermia protocol for the aortic root surgery is the same as in the standard open-heart surgery (28–30°C), unless
there is a need for arch surgery for hypothermic circulatory arrest with antegrade selective cerebral perfusion (<25°C) [30].
After cardioplegic arrest is accomplished by antegrade perfusion through the aortic root in cases where there is no aortic
regurgitation, or by retrograde perfusion through the coronary sinus if clinically significant aortic regurgitation is present,
myocardial protection is achieved via an antegrade (direct coronary ostia) or a retrograde (through the coronary sinus)
route. Depending on the aortic root pathology, the suggested initial methodology starts with retrograde cardioplegia and
delivers antegrade cardioplegia via the directly exposed coronary ostia.
Ministernotomy Techniques
Minimal invasive root replacement surgery is becoming increasingly popular because of shorter hospitalization periods
and cosmetically improved results in the experienced hands [31]. Outcomes in selected centers offer a variety of improved
results such as shorter intensive care unit stay, improved lung functions, reduced trauma effects, and early mobilization.
This approach provides only limited exposure of the heart but results in fewer adhesions than full-median sternotomy,
which is useful in reoperations. This advantage in redo-operations, along with the limited exposure of the upper mediastinum through the mini-incision, may prevent right heart injury.
There are a few minimally invasive incision techniques for access into the mediastinum. J sternotomy is the most preferred
ministernotomy incision in isolated AVR operations, where the sternum is incised from the sternal notch caudally to the right
fourth intercostal space [32,33]. But only upper reverse-T ministernotomy is the appropriate approach to reach the aortic root
and to perform all varieties of aortic root surgeries [34,35]. This technique is very easy as is full-median sternotomy, where an
oscillating saw with a narrow blade is used to cut the sternum, which is started from the sternal notch and extended vertically to
the third intercostal space and then converted to an inverted- “T” shape without mobilization or ligation of the internal thoracic
arteries (Fig. 26.1). This incision allows for a visualization of the aortic root, the pulmonary artery, and the superior vena cava.
The right atrial appendage can be left under the sternum, but it is easy to pull it into the surgical field.
After the usual preparations, arterial cannulation can be established centrally (aortic arch) or peripherally (right subclavian artery). In both approaches, an ECMO arterial cannula, which is inserted directly through a purse-string stitch with
the sliding technique, should be used to prevent complications and to obtain more free area in the surgical field. Venous
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FIGURE 26.1 Upper reverse-T ministernotomy.
cannulation is performed with a small, single, two-staged venous cannula through the right atrial appendage. Venous return
is maintained via a negative vacuum venous drainage system. Another alternative for venous cannulation is to insert an
appropriate ECMO venous cannula through the femoral vein and to connect it to the negative vacuum system. A negative
vacuum system is very effective in emptying the heart and can achieve left heart decompression without the use of a vent
cannula. If it is not effectively decompressing the heart and providing a bloodless surgical area, a vent cannula may be
passed through the right upper pulmonary vein into the left atrium or it may be placed in the pulmonary artery.
Prosthetic Valve
The use of a composite graft along with a mechanical valve seems the most preferred option during elective or urgent
ARR because of its simple handling, easy sizing, lower profile, long-term durability, and resistance to mechanical stress.
Bioprosthetic valves can be chosen in elective procedures in older patients to avoid long-term anticoagulation. The optimal
prosthetic valve for en bloc ARR is controversial in younger patients. Since percutaneous valve implantation procedures
have been available from the last decade, failing bioprosthetic valves can be replaced by valve in valve techniques, which
have been reported with acceptable results in high-risk patients [36,37]. Allograft ARR may be the best option for aortic
root pathologies, especially for active aortic valve endocarditis with root abscess, but their use is very limited because of
inadequate donor availability and less durability. Pulmonary autograft is more useful in pediatric patients; however, early
neo-aortic valve regurgitation is an important risk when it is used in young adults. Finally, porcine aortic root xenograft of
different sizes can be an option to replace total aortic root, but late complete degeneration and en bloc calcification are the
most frequent complications.
OPERATIVE TECHNIQUES
Conventional open-heart surgery is the essential procedure for isolated ARR. If the ascending aorta and/or distal aorta
require any surgical replacement, different approaches can be used for cannulation and systemic circulation and also for
cerebral protection. The anatomopathologic findings of the aortic root pathology refer surgeons to prefer the optimal operation alternative (Table 26.2). The main goal of surgical treatment is patient survival, followed by prevention of early and
late adverse outcomes and finally the minimization of surgical interventions [38]. It is always a good idea to keep in mind
that the ARR surgery is a lifesaving procedure and there are not many drawbacks to the conventional procedures. Less invasive or aggressive interventions may be chosen in elective and selective cases, but these surgical techniques have their own
advantages and disadvantages, which should be considered preoperatively in the decision for the most appropriate approach
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TABLE 26.2 Aortic Root Replacement Techniques
A. Total Aortic Root Replacement
I. With aortic valve replacement
1. Modified Bentall procedure
2. Cabrol procedure
3. Flanged procedure
4. Biologic Bentall procedure
a. Allograft
b. Xenograft
5. Ross procedure
II. Without aortic valve replacement (Valve-Sparing Aortic Root Replacement)
1. Remodeling (Yacoub procedure)
2. Reimplantation (David V procedure)
B. Subtotal Aortic Root Replacement (Without Aortic Valve)
1. One-sinus replacement
2. Double-sinus replacement
3. Sinus of Valsalva aneurysm repair
C. Extensive Aortic Root Replacement (With Aortoventricular Base)
TABLE 26.3 Decision Steps for Aortic Root Surgery
1. “if ARR”, total or subtotal procedure
2. “if total ARR”, aortic valve–sparing or replacement technique
3. “if total ARR + AVR”, biologic or prosthetic composite conduit
4. “if prosthetic composite conduit”, mechanical or biological valve
ARR, aortic root replacement; AVR , aortic valve replacement.
for the patient (Table 26.3) [39]. The first goal during ARR is to spare the competent aortic valve if possible. If not possible,
then the appropriate prosthetic valve must be chosen [40].
Total Aortic Root Replacement Procedures
Total ARR is a technically exhaustive operation, and experienced surgeons should know the detailed anatomy and hemodynamic function of the aortic root. Total ARR may be unavoidable after removing all weak and diseased tissues on the aortic
root, and all sinuses should be resected and coronary ostia should be prepared as buttons. After aortic cross-clamping, a
2-cm transverse aortotomy is performed just above the STJ to visualize the aortic root and leaflets, then the ascending aorta
is divided completely. The second step is resection of aortic sinuses, which remains 3–5 mm over from the aortic annulus,
and preparing the coronary buttons with a 1.5-cm-diameter cuff of aortic wall and mobilizing over a short length to facilitate
reimplantation. The aortic valve can be spared if it has a normal functional structure, but any doubt regarding aortic valve
function after surgery necessitates replacement of the aortic valve. All other necessary concomitant procedures such as
distal anastomosis of coronary bypass grafts and/or valvular repair/replacement are performed before total ARR.
With Aortic Valve Replacement
Modified Bentall Technique
The modified Bentall operation is the gold standard for the ARR (Fig. 26.2). The “modified” procedure describes the discontinuation of the practice of wrapping the aortic wall over the graft and the button anastomosis of the coronary ostia rather than
as required in the originally described technique. After the removal of all aortic tissues, the first step is the implantation of a
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FIGURE 26.2 Modified Bentall (Button) technique.
composite graft onto the aortic annulus to build the neo-aortic root. Standard aortic valve stitches with pledgets are inserted
circumferentially in a stepwise direction starting from the commissure between the non- and the left-coronary sinuses from
outside to inside. Three mattress stitches of 2-0 polyester with pledgets for each sinus and one for each commissure are usually
enough to cover all aortic annulus in most cases. The surgeon may decide to use commercially available prepared composite
valve grafts or any valve with any graft to create a custom-made composite material. Commercially prepared valve composite
material can save time, whereas the custom-made materials can be more flexible. After stitches at the aortic root are crossed
without interruption from the composite material (both sewing ring of prosthetic valve and graft), the composite material is
positioned down to the aortic root and stitches are tightly tied. To prevent postoperative bleeding from the proximal anastomosis, a reinforcement suture joining the incised edge of the aortic wall and the prosthetic sewing ring can be used [41]. The
miniskirt technique has been developed to secure proximal bleeding, where first all interrupted mattress sutures enter the aortic
annulus, the sewing ring of the prosthesis, and the vascular graft leaving a short segment, and then proximal hemostasis is
secured with a running suture by buttressing the aortic remnants and graft edge [6]. Alternatively, a short skirt of Dacron tube
can be added to the proximal end of a standard composite graft and sewn to the remaining native aortic wall to wrap the proximal annular anastomosis after the completion of the implantation of this modified composite graft on the aortic annulus [42].
The second step is coronary ostial anastomoses to reestablish myocardial revascularization with a Carrel patch (button) technique or alternatives (Fig. 26.3A). Left main coronary ostium is anastomosed directly to the created orifice on the
posterior side of the ascending graft with continuous 5-0 polypropylene suture. Similarly, the right coronary anastomosis
is performed. When the use of this standard technique is not feasible, the Trapdoor technique can be used to reduce tension
on the anastomosis and to prevent rotation from the original location (Fig. 26.3B) [43]. Another alternative is a small graft
interposition between the coronary ostium and tubular graft (Fig. 26.3C). Newly developed grafts with prefabricated coronary branches are an alternative to reduce coronary anastomotic complications [44]. If there is any problem with coronary
ostial anastomoses, coronary artery bypass grafting and ligation at the level of the ostium should be performed [45].
The third and last step is the distal anastomosis to complete proximal aortic continuity. The distal end of the tubular graft
is cut to approximate the distal ascending aorta and anastomosed in the “end-to-end” fashion using continuous 4-0 polypropylene suture. Any support via Teflon felt or pledget is not necessary during coronary and distal anastomoses; however, all
stitches should be placed with deep bites into the aortic wall depending on its thickness and strength.
Cabrol Technique
Intraoperative anastomotic difficulties or late complications of coronary ostial anastomoses directly to the composite tubular
graft with the button technique have lead surgeons to investigate alternative techniques for coronary anastomoses. During
the historical progression of the ARR, the coronary ostia were anastomosed to the ascending tubular graft using various
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FIGURE 26.3 Coronary ostium anastomotic techniques: (A) Carrel; (B) Trapdoor; and (C) interposition graft.
FIGURE 26.4 Cabrol techniques: (A) Interposition graft; (B) separate small interposition grafts; and (C) interposition graft + Button anastomosis.
techniques, but only modified Cabrol procedures have been accepted worldwide. Except coronary ostium anastomoses, all
operative steps are similar to the modified Bentall procedure, as described in detail above. The classic Cabrol technique is carried out using a “moustache-shaped” interposition tubular graft (8 mm) between coronary ostia and aortic graft. This technique
can be very useful in reoperation procedures, where the mobilization of the coronary buttons is difficult, in extremely large
aortic diameter, and also in severely calcified coronary ostia. Because this technique has worse outcomes because of stenosis,
thrombosis, and occlusion of the longer interposition graft, several modifications of this classic technique have been developed to mitigate these problems [46,47]. There are three alternatives: an interposition graft can be anastomosed conjointly to
the coronary ostia in an “end-to-end” fashion and then “side-to-side” to the aortic graft (Fig. 26.4A); two small interposition
grafts can be anastomosed between each coronary ostium and aortic graft separately (Fig. 26.4B); one coronary ostium can be
anastomosed directly and the second ostium is anastomosed with a separate interposition graft to the aortic graft (Fig. 26.4C).
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Flanged Technique
Intraoperative anastomotic difficulties of the proximal end of the composite graft have forced surgeons to develop new
approaches to prevent bleeding or dehiscence at the annular anastomosis. Our clinic has introduced a new technique to
achieve the continuance of the flexibility and elasticity of the proximal end of the composite graft [48]. Except when
preparing a homemade prosthetic composite conduit and annular implantation, all initial and operative steps are similar
with the modified Bentall procedure. This method may be the best alternative for tailoring the aortic root in all aortic root
pathologies, especially in patients with a small aortic root requiring posterior annular enlargement, calcified aortic annulus,
aortic root abscess, or subannular defects (Table 26.4).
In this technique, we select a prosthetic valve with the appropriate size to prevent patient–prosthesis mismatch, and a
4- to 8-mm larger prosthetic tubular graft to create pseudosinuses that allow reimplantation of the coronary ostia without
greater mobilization, any tension, or kinking (Fig. 26.5). First, the proximal end (8–10 mm in length) of vascular graft is
everted outward to build the flange and the sewing ring of stented prosthetic valve is anastomosed with continuous 4-0
polypropylene suture onto the tubular graft, and then the flange of the conduit is returned to its original position, where the
length of the graft is left 5 or 6 mm for anastomosis of the conduit to the annulus. The length of the flange (1–3 cm long)
TABLE 26.4 Advantages of the Flanged Technique
1. Avoidance of patient–prosthesis mismatch
2. Maintenance of the flexibility and dynamic function of aortic annulus
3. Quicker and safer implantation of composite valve graft
4. Easier anastomosis of the flanged portion to the aortic annulus
5. Tailoring the flanged portion according to the pathology
6. Creating widest pseudosinuses to simplify the direct anastomosis of coronary ostia on the graft without
tension or kinking
7. Performing aortic annular enlargement
8. Repairing subannular defects
9. Preventing proximal bleeding
FIGURE 26.5 Flanged technique.
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is adjusted depending on the procedure (i.e., from noncomplicated to complicated aortic root pathologies). The flange of
the composite graft is implanted to the aortic annulus with a continuous 3-0 polypropylene suture. The aortic annulus with
∼3 mm aortic valve tissue, which remains from the resected aortic leaflets, and the 3- to 5-mm proximal part of the ascending aorta, which remains from the transected aortic wall, can be used as a double-sided strip (the free end of the tubular graft
is interposed between these tissues) over the proximal anastomosis to prevent surgical intraoperative or postoperative bleeding and consequently late pseudoaneurysm. If pledgeted mattress sutures are used, it can be feasible by suturing the free end
of the flange to the residual aortic wall to prevent postoperative bleeding and late pseudoaneurysms [49]. The level of the
prosthetic valve in the tubular graft is higher than that in the modified Bentall procedures, but it is never higher than 4–5 mm
from the aortic annulus, and this upper location of the prosthetic valve does not hinder coronary anastomoses. The newly
created pseudosinus tubular graft is the main preventive maneuver of this technique against stretching or kinking of the button anastomosis. Another option is using a flanged composite graft with two separately interpositioned grafts to anastomose
the coronary buttons [50]. Valsalva tubular grafts can also be used to prevent the anastomotic complications [51]. The distal
anastomosis of the composite tubular graft is performed in the same way as in the modified Bentall procedures.
Biologic Bentall Technique With Tissue Composite Graft
The use of biologic composite grafts in ARR has been very popular in the last 50 years to avoid bleeding and thromboembolic complications of mechanical valve. The advantages of the biologic Bentall technique are excellent hemodynamic
profile similar to the native aortic root, very low transvalvular gradient, no anticoagulation, and very low risk of infection;
however, the main disadvantage is structural degeneration. The main indications are active destructive aortic valve endocarditis with root abscess, small aortic root in older patients, and contraindications against anticoagulation.
1. Cryopreserved human allografts (aortic or pulmonic) offer reliable long-term durability and can be used in young adults
with active lifestyle, especially for infective endocarditis. Fresh homografts can be prepared from recipients during
heart transplantation and used immediately [52]. Reoperative root replacement in patients with expected survival of less
than 10 years and any need to avoid anticoagulation are the remaining indications for the use of allografts. But the use of
allografts is infrequent because of limited availability of donors and the larger size roots. There are three major surgical
techniques: subcoronary, root inclusion, and root replacement. The root replacement technique has several advantages
such as no distortion of the commissural positions, no asymmetry for the size mismatch, and the total exclusion of the
native root pathology. In case of a need of a patch or tissue below the aortic annulus, the mitral anterior leaflet of the
allograft is also trimmed. The most important detail is the orientation of the allograft to the aortic annulus (Fig. 26.6).
The coronary ostia of the aortic allograft and the native aortic root must meet each other perfectly. If not, at least both
FIGURE 26.6 Allograft replacement.
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left coronary ostia have to match each other to avoid any kinking or tension because the native left button remains pos-
terior and any problem here would be difficult to manage. Pulmonary allograft implantation is performed as in the Ross
procedure. The suture line can be interrupted or continuous, and 3-0 or 4-0 polypropylene sutures are used. Suture line
starts from the middle level of the left coronary sinus (LCS), advancing to the right coronary sinus (RCS) and then to
the noncoronary sinus (NCS) all through the 0.5 mm below the annular tissue avoiding any conduction abnormalities.
After proper alignment to the root, coronary anastomoses are performed with 5-0 polypropylene suture.
2. Xenograft is a useful option for biologic Bentall because of the large availability of different sizes, improved durability,
stentless structure, and reduced cost. Implantation of xenografts is very similar to aortic allograft. Xenograft to coronary
button orientation is important, especially for the porcine xenografts, which usually do not exhibit the proper angulation
like allografts [53]. For coronary alignment, in most cases the porcine root is rotated 120 degrees during implantation,
so that the NCS of the xenograft can be used for reimplantation of one coronary button [54].
Ross Technique
ARR with a patient’s own pulmonary autograft was first performed by Ross [55] and popularized over the last couple of
decades especially in children and adults with active lifestyles. The pulmonary root can be an optimum substitute to the
native aortic root, with similar physiology and hemodynamic profile. This technique must be used as an elective option
and requires expertise in aortic and also pulmonary roots, and attention to the origin of the left main coronary artery is
mandatory because of its proximity to the pulmonary root. Transferring the pulmonary root to the aortic position necessitates the replacement of the pulmonary root with a pulmonary allograft or stentless porcine root [56]. The size difference
between aortic and pulmonary annulus should not be more 2 mm; otherwise, the diameter of the dilated aortic annulus
should be reduced. The orientation of the pulmonary autograft to the aortic root is a critical point of this operation, and
the posterior sinus of the pulmonary autograft must be the left sinus. To prevent late dilatation of the neo-aortic root, an
externally supported Ross procedure (supported Ross) consisting of a prosthetic graft to support the neo-aortic root can be
used in adolescent and adult patients [57]. The main advantages of the Ross technique are resistance to infection, no need
for anticoagulation, and capability for somatic growth. However, the technical complexity of the operation and the risk of
reintervention of the biologic grafts have limited widespread usage of the Ross procedure [58,59]. The long-term results of
the Ross procedures are far better than non-Ross valve replacement in children in terms of early and late mortality, freedom
from reintervention, and postoperative transaortic gradients [60]. But this approach is not an alternative to conventional
AVR in adults [61].
With Aortic Valve Sparing
Aortic root pathology with normal anatomic structure of the aortic leaflets causing significant aortic regurgitation is the
primary indication for sparing aortic valve with/without aortic valve repair during total ARR [62]. Aortic valve–sparing
procedures allow avoidance of anticoagulation, prosthetic material, and postoperative transvalvular gradient. There are two
major techniques with their own advantages and disadvantages. Yacoub technique is preferred if any annular stabilization
is not necessary, while the David technique is essential if annular stabilization is inevitable. The proximal anastomosis is
completely different from valvular composite graft procedures, but coronary and distal anastomoses have similar surgical
technical details as the modified Bentall procedure.
Remodeling Technique (Yacoub Procedure)
After resecting three sinuses of Valsalva and leaving approximately 5 mm of aortic wall above the annulus for suturing of
the tubular graft, the three commissures are hung up until the aortic leaflets coapt, and then appropriate sizing is performed
to select the suitable graft. The stentless valve seizer is the easiest way to measure the annular diameter, and the number
of seizer is the true graft size when it fills the aortic annulus. Three commissures are marked on the tubular graft and it is
tailored to make three neo-aortic sinuses, and their heights should be equal to the diameter of the graft. The graft with three
tongues, which will act as pseudosinus, is sutured to the aortic wall at the annulus with three continuous 4-0 polypropylene
sutures, button anastomoses are performed as described, and then the aortic valve competence is assessed by filling the
tubular graft with saline (Fig. 26.7). The distal anastomosis is completed as usual.
Reimplantation Technique (David V Procedure)
All steps of the reimplantation technique are similar as in the remodeling technique until graft preparation and suturing.
There are several options to create Valsalva sinuses. Because the straight graft causes native aortic valve deterioration, after
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FIGURE 26.7 Yacoub remodeling technique.
TABLE 26.5 Stages for David V Reimplantation Technique
1. Selection graft type (tubular or Valsalva graft)
2. Choose measurement method (graft sizing)
3. Calculation of appropriate size
4. Accordance to body surface area
5. Stabilization of aortic annulus
6. Resuspension of commissures
7. Creating neo-STJ (proximal–distal graft diameter ≥ 4 mm)
8. Reshaping neo-sinuses
several modifications of reimplantation technique it is well understood that pseudosinuses are essential for avoidance of
late valve degeneration and the optimized reimplantation technique contains either a larger proximal graft (David V) or
fabricated Valsalva sinuses. If tubular grafts are used, the larger graft is preferred for neo-aortic root and the smaller graft is
used for neo-ascending aorta. If Valsalva graft is used, only one tubular graft is appropriate to perform the reimplantation
technique. We prefer two tubular grafts option.
There are several principles or key points during David V operation (Table 26.5).
After the ascending aorta is transected just 2 cm below the cross-clamp, the ascending aorta is cut until 1 cm above the
anterior (right coronary—noncoronary cusps) commissure. A 2-0 pledgeted polyester suture is then placed 5 mm above the
tab of this commissure, which is used later for commissural resuspension. The incision is continued along the RCS leaving
the 5-mm aortic wall and the right coronary ostium is prepared as a button. When the incision arrives at the tab of the left
(right—left coronary cusps) commissure, the second pledged suture is placed here. The next step is continued at the right
side and the incision is extended throughout the NCS annulus leaving an aortic rim, and the last pledgeted suture is placed
on the tab of the posterior (left—noncoronary cusps) commissure. The removal of the LCS is performed and the left coronary ostium is prepared. The whole proximal aorta with aortic sinuses is removed.
The most important step is to size the appropriate graft for the neo-aortic root. If the ascending aorta dilatation causes
aortic regurgitation with normal aortic annulus, graft size must be equal to the annular diameter. In all other situations with
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