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2. In the presence of commissural detachment and subsequent aortic insufficiency resulting from leaflet prolapse [90],
commissural resuspension is made before graft insertion. The commissures could be resuspended with 4-0 polypropyl-
ene-pledgeted sutures that also occlude the dissected space; in case of cusp prolapse, a resuspension of the free edge
near the commissure using pledgeted suture could be added, and, finally, when annular dilatation is present, it can be
used for the plication of the aortic wall at each commissure or an encircling suture of the whole aortic circumference
(circumcision), but the latter should be used with precaution because of the tendency to distort the sinuses [91].
3. In cases where the aortic valve is affected by congenital or acquired abnormalities and cannot be conserved in a durable
manner, the surgical option consists in aortic valve replacement with separate insertion of a supracommissural graft
[92,93], according to the tenets of the original Wheat–Shumway–Groves procedure, with minimal sinus tissue remain-
ing above the annulus except for tongues surrounding the left and right coronary ostia [94,95] (Figs. 28.4 and 28.5).
In any case of superimposed ATAAD on a previously ectatic vessel or if the dissection involves at least one sinus of Valsalva,
it is preferable to replace the aortic root, rather than to perform a supracoronary ascending aorta replacement only. The latter is
associated with late dilation of the aortic sinuses and recurrence of aortic regurgitation and requires a high-risk reoperation.
Preference in this group of patients is to perform root replacement with a composite valve graft (CVG) because the
dissected proximal layers are totally eliminated. There exist three principal variants of composite graft insertion, but the
best-known procedure for complete replacement of the aortic root and ascending aorta is the original technique described
and introduced by Bentall and De Bono in 1968 [96–100]. This procedure consists in removing the aortic cusp and tailoring an adequate portion of the aneurysmal aortic wall, just enough to place the Dacron tube graft inside, with no free space
left between the walls of the tube graft and aorta. After annulus sizing, the pledgeted mattress are placed horizontally on
FIGURE 28.3 Interposition of a tubular graft it is made which is anastomosed at the sinotubular ridge, proximally and distally to the uninvolved aorta,
just near the origin of the innominate artery.
FIGURE 28.4 Aortic valve replacement.
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FIGURE 28.5 The original Wheat–Shumway–Groves procedure—aortic valve replacement and supracommissural graft insertion.
the aortic side of the annulus and afterward passed sequentially through the sewing ring of the valve prosthesis [101]. Once
the prosthesis is seated, the sutures are tied and cut, and the coronary buttons in the tube graft are created [102]. Round
openings of two to three times larger than the diameter of coronary ostia are made in the graft and remnants of the arterial
walls around the coronary arteries are sutured to the graft in an end-to-side fashion with continuous 5-0 polypropylene
sutures [103]. But leaving the coronary ostia in continuity with the aorta could favor the formation of perigraft hematomas
or perfused perigraft space and late pseudoaneurysms or a pressurized aneurysm sac at the ostial anastomoses [104–110].
So, beyond a classic Bentall procedure, Kouchoukos and coworkers [111–113], Svensson and colleagues [114,115],
and Griepp’s group [79], made some modifications to it, which are thought to be necessary for a reliable procedure, using
full-thickness Carrel patches (or buttons) for coronary reimplantation to avoid the complications that plagued the classical
“wrap inclusion” Bentall procedure [116] (Figs. 28.6 and 28.7).
FIGURE 28.6 Modified Bentall procedure by Kouchoukos.
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(A)
(B)
(C)
FIGURE 28.7 Modified Bentall technique by Kouchoukos et al. using a composite valve graft (CVG). (A) Insertion of the CVG with individual pledgeted mattress sutures placed on the aortic annulus. (B) Reimplantation of the left coronary ostia as a Carrel patch or “button.” (C) After completing the
distal anastomosis of the tubular graft to the nondissected ascending aorta, just below the origin of the innominate artery, the right coronary is anastomosed
in the same manner as the left coronary.
Various alternative techniques exist for reimplantation of the coronary ostia or preservation of the ostia of the coronary
arteries [117,118], among this is Cabrol moustache technique, which is a dedicated technique for creating “tension-free”
anastomoses in cases of tight adhesions, such as aortic root reintervention or large dissections [119], and consists in an endto-end anastomosis between the left coronary orifice and a synthetic graft (Dacron or polytetrafluoroethylene), followed
by the anastomose of the opposite end of the conduit to the right coronary ostia in an end-to-end fashion as well, and to
complete the procedure, the single coronary conduit was made continuous with the valvular duct via a single side-to-side
anastomosis (Figs. 28.8 and 28.9). Cabrol and colleagues introduced another adjunct to the routine CVG in case of difficult
hemostasis, which consists in creating a drainage shunt from the periprosthetic space into the right atrium or SVC, thereby
decompressing it [120–123].
An alternative to synthetic graft is the use of short-interposition saphenous vein graft, a method proposed by Zubiate and
Kay, and in exceptional circumstances, suture ligation of the coronary and bypass grafting (Fig. 28.10) [124,125].
The second option regarding the conservative attitude toward the valve per se can be continued by using various types of
valve-sparing techniques, which have been popularized in recent years. Aortic valve sparing is not a new concept but rather
reflects the advanced surgical and biomechanical innovation of modern cardiac surgery [126,127].
Tirone David’s “reimplantation” valve-sparing aortic root replacement pioneered by David et al. [128–134] and the
Yacoub “remodeling” procedure introduced and used since 1979 by Sir Yacoub et al. [135–137] have been shown to have
satisfactory 15-year results in proper experienced hands, but these techniques are more likely to be used in chronic type A
aortic dissection [138,139].
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FIGURE 28.8 Cabrol procedure.
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FIGURE 28.9 Cabrol procedure: After insertion of the composite valve graft with individual pledgeted mattress sutures placed on the aortic annulus,
an end-to-end anastomosis between the left coronary orifice and a synthetic graft (Dacron or polytetrafluoroethylene) is made, followed by the distal
anastomosis of the tubular graft to the nondissected ascending aorta, just below the origin of the innominate artery. (A) The opposite end of the conduit is
anastomosed to the right coronary ostia in an end-to-end fashion as well. (B) The single coronary conduit was made continuous with the valvular duct via
a single side-to-side anastomosis. (C) Final aspect of the Cabrol technique.
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(A)
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FIGURE 28.10 Alternative to synthetic graft—the interposition of saphenous vein graft. Method proposed by Zubiate and Kay.
(B)
(D)
(C)
FIGURE 28.11 Yacoub procedure: (A) Excision of the aortic wall within 2–3 mm of the leaflet attachments. (B) The Dacron is fashioned into three
separate tongue-shaped processes that act as individual sinuses and the commissural stitches are placed and drawn into the graft. (C) The aspect of the
graft showing fixation of the valve remnants sewn in place. (D) Procedure completed along with hemiarch replacement.
(D)
Yacoub procedure involves excision of the aortic wall to within 2–3 mm of the leaflet attachments, detachment of the
coronary ostia, reshaping of the annulus with the aid of a Dacron graft that can be ensured by refashioning it to produce
three separate tongue-shaped processes that act as individual sinuses, and then reimplantation of the coronary arteries
(Fig. 28.11) [140].
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The David technique is performed as follows: after excision of the sinuses of Valsalva to the deepest points of them,
retaining only 3-mm strip of the aortic wall, the aortic valve is implanted inside a straight (not tailored) Dacron tube in a
manner similar to the implantation of an aortic valve homograft; this is followed by reimplantation of the coronary ostia as
buttons [141–144].
In selected patients with extensive destruction of the noncoronary sinus and in some cases the right sinus, a limited
aortic root remodeling operation (uni-Yacoub or bi-Yacoub) is appropriate. In the uni-Yacoub technique, the entire noncoronary sinus is excised and replaced by an “U-shaped” tongue fashioned from the aortic graft and sutured close to the
hinge of the aortic cusp. In case both sinuses are destroyed, noncoronary and right sinuses, the bi-Yacoub procedure could
be used with right coronary artery reimplantation as a Carrel patch into the Dacron tongue [16].
Distal aortic anastomosis: A current topic of debate is the extent of aortic repair: How much distal operation is enough? How
much is too much? Or like the mantra says: not to chase the dissection into the arch unless it is required as a last resort [145–150].
The optimal management of the aortic arch in an ATAAD is highly variable and should be tailored to the patient’s clinical presentation, the anatomy of the arch and distal aortic anatomy and the location and extent of the intimal tear, collapse of
the distal TL, and the presence of dynamic or static obstruction of the branch vessels of the aortic arch or distal aorta [151].
For patients with a tear localized to the ascending aorta (DeBakey type II) or in the inner curvature of the arch who have a
normal-caliber aortic arch without distal malperfusion and additional arch complications, the standard surgical repair involves
a hemiarch replacement, with the distal anastomosis sutured in a transverse manner to resect the inner curvature of the arch
and sparing the supraaortic branches [152], so the graft is anastomosed to the uninvolved distal aorta using a continuous overand-over suture, which generally does not have to be supported with Teflon-felt. When using the remodeling procedures, to
facilitate the coronary ostia implantation and resuspension of the valve, the graft must be kept short; therefore, often another
graft is required for bridging the distance to the distal aortic anastomosis (Fig. 28.11D) [79]. So it is first anastomosed downstream and then is connected to the root graft in a continuous over-and-over suture. A new approach of the hemiarch technique
is by using a “neo-media” technique, where a piece of felt is trimmed and placed between the adventitia and intima of the arch.
Subsequently, using a running 4-0 polypropylene, the wall of neo-hemiarch is constructed. Afterward, the graft is beveled to
reconstruct the curve of the arch and is then sewn to the hemiarch anastomosis with a running 4-0 polypropylene stitch, an
on-lay intussuscepting anastomosis with the graft placed inside the aorta for optimal hemostasis [153].
Traditional surgical techniques focus on open distal anastomosis [154–156] and, as a second technical truth, it permits a
more satisfactory technical result as it allows a more accurate approximation of the dissected layers and a direct visualization
of any arch tears [157–159], resulting in a more secure hemostatic anastomosis, whereas a closed anastomosis always results
in a cramped, distorted region at the posterior tip of the clamp, which is a frequent source of bleeding. Also, the mere application of a clamp forces the anastomosis considerably more proximally on the aorta, resulting in a less complete resection of
the ascending aorta and can induce FL pressurization, leading to propagation of the dissection and malperfusion. There is also
increased risk of inducing additional aortic injury via the clamp itself (Figs. 28.12 and 28.13) [39,160,161].
FIGURE 28.12 Distal open anastomosis—in deep hypothermic circulatory arrest—to the uninvolved distal aorta using a continuous over-and-over
suture, supported with Teflon-felt.
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Aortic arch replacement: In case of extensive tears in the aortic arch, which is present in 15%–20% of all ATAAD
patients [162], and in the presence of arch aneurysm, complex arch dissection, connective tissue disease [163–167], or atheromatous disease, total arch replacement should be considered [168–172]. The reimplantation of supraaortic vessels can
be done “en bloc” as an island or vessels anastomosed individually via branched graft (Fig. 28.14).
FIGURE 28.13 Distal open anastomosis—in moderate hypothermic circulatory arrest with selective ACP—to the uninvolved distal aorta using a continuous over-and-over suture. Reprinted from de la Cruz KL, Caselli JS, LeMaire SA. Open Aortic Arch Replacement: A Technical Odyssey. J Extracorpor
Technol, March 2012;44(1):P42–7. Reprinted with permission.
FIGURE 28.14 A completed total aortic arch replacement by the traditional elephant trunk approach. At the distal anastomosis, the tubular aortic graft has been
sewn directly to the aneurysmal descending thoracic aorta. The brachiocephalic branches have been reattached by using the island technique. The “trunk” of graft
is left suspended in the descending thoracic aorta to be used during the subsequent second-stage repair of the remaining distal aneurysm. Reprinted from de la Cruz
KL, Caselli JS, LeMaire SA. Open Aortic Arch Replacement: A Technical Odyssey. J Extracorpor Technol, March 2012;44(1):P42–7. Reprinted with permission.
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FIGURE 28.15 Aortic arch debranching and endograft repair.
A new transverse aortic arch replacement technique uses a prefabricated two-branched graft in which the distal end of
the graft is anastomosed between the left common carotid artery and the left subclavian artery to make distal anastomosis
easier and to avoid recurrent nerve injury, with or without a Teflon-felt strip on the outside of the aortic wall to reinforce
the anastomosis site [173], with the left subclavian artery receiving blood supply through the space between the graft and
aortic wall or could be anastomosed to the side branch.
A second option is to use a prefabricated triple-branched graft with side perfusion branch [174], in which case the distal
graft anastomosis is performed at the proximal descending aorta just distal to the origin of the left subclavian artery.
In an attempt to minimize the risks and morbidity associated with aortic arch replacement, a new approach has emerged—
the branch-first continuous perfusion technique, in which there are no periods of global cerebral circulatory arrest or deep
hypothermia, with encouraging early results [175–178]. Arch replacement using the “branch-first” technique allows for complete root, ascending, and arch replacement and a long landing zone for proximal endografting with a covered stent (Fig. 28.15)
[179,180]. This allows removing the time pressures associated with circulatory arrest and thus reducing some of the pressure
placed on the surgeon, allowing for an unhurried and more technically precise anastomosis even in the most technically
demanding reconstructions. In essence, the procedure consists of five major steps: establishment of CPB using femoral inflow
and moderate hypothermia; followed by serial disconnection and reconstruction of each arch branch (proceeding from innominate to left subclavian) using a trifurcation arch graft with a perfusion side arm port (TAPP graft; Vascutek Ltd., Renfrewshire,
Scotland, UK) [177]. After completion of the innominate anastomosis, the perfusion side arm port is used for selective ACP
for the remainder of the procedure; clamping of the proximal descending aorta and construction of the distal arch anastomosis;
completion of aortic root reconstruction; and finally connection of the common stem of the trifurcation graft to the ascending
aortic graft. The technique of total aortic repair described above allows the successful management of ATTAD with reliable FL
obliteration of all dissected thoracoabdominal aorta. In doing so, branch vessel ischemia is treated, TL perfusion is ensured,
and aortic healing is encouraged and the aorta is provided structural support from the stent graft [181,182].
THE ELEPHANT TRUNK PROCEDURE
The distal anastomosis may be constructed with an elephant trunk, a free-floating extension of the arch prosthesis, depending on the size of the overall aorta and the size of the TL beyond the arch and has been widely used for its purpose in preparing and facilitating surgery on the downstream aorta after total arch replacement, introduced by Hans Borst from Hannover
in 1983 (see Fig. 28.14) [183–185]. For the classic elephant trunk, there are two modes of inserting: first by invaginating the
arch portion into the elephant trunk, described by Crawford [186,187], and the second option, in which the elephant trunk
is telescoped retrogradely into the arch graft (Fig. 28.16) [188,189].
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FIGURE 28.16 Elephant trunk procedure and total aortic replacement.
But the conventional elephant trunk (cET) technique has his complications as Crawford and associates [190] reported:
kinking and occlusion of the graft, paraplegia as a result of clotting around the graft, and peripheral thromboembolism
caused by flapping action. To avoid these potential complications of a long elephant trunk graft, Kato et al. [191–193], in
1996, used to deliver and secure a stent graft far more distally than is possible with a conventional Borst elephant trunk
graft. Thus, any kinking and flapping action of the graft could be prevented. In addition, the dead space around the graft
could be completely obliterated [194].
HYBRID PROCEDURES
Direct surgical approach, through a median sternotomy, for dissection of the aortic arch has been an established, timetested procedure with satisfactory results and durability, but there are cases when performing anastomosis and hemostasis
at the deep portion beyond the left subclavian artery is often associated with difficulties, needing more often extension of
the exposure, just like clamshell incision or left thoracotomy and even two-stage repair with elephant trunk [195,196], as
described before. And of all the patients with visceral or renal malperfusion who often have their primary entry tear in the
descending aorta, these are the patients who might profit from extended therapies, such as “frozen elephant trunk” (FET)
repair [78].
Therefore, the time is now right to transition into the next phase of sophistication in the management of ATAAD with
the aim of achieving not only a safe acute operation but also to either entirely prevent chronic complications or to greatly
simplify their management by the creation of an anatomical situation that facilitates future endovascular intervention in
place of complex redo surgery [197]. In the past years, different hybrid approaches have been adopted, techniques consisting of open multiple-branched stent graft placement, aortic arch debranching and stent deployment, stented elephant trunk,
and FET. As a step between the cET technique and the so-called FET technique [198], the combination of varying extents
of aortic arch replacement and antegrade thoracic endovascular aortic repair (TEVAR) was practiced until a combined
prosthesis became available that combines conventional aortic surgery and endovascular repair [199,200].
The open stent graft technique is a hybrid procedure that brings both techniques (open surgery and endovascular techniques) (Figs. 28.17 and 28.18) [201] closer together to create a common platform for a combined treatment. FET entails
conventional surgical repair of the most proximal thoracic aorta using circulatory arrest through a sternotomy combined
with direct antegrade delivery (open stent graft) advocated by Pochettino and colleagues [202] and suturing of a stent graft
device to extend the repair through the aortic arch and into the upper portion of the descending aorta [203,204] or with the
aid of intraoperative fluoroscopy after termination of CPB [205].
There are no randomized studies comparing “extended-arch” strategies with conventional “open distal anastomosis”
technique for acute type A dissection surgery. However, potential advantages of a hybrid repair technique include sealing
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(A)
(C)
(B)
(D)
FIGURE 28.17 Intraoperative photographs (A and B) show placement of the stent graft into the descending aorta. The Dacron graft is pulled out to
perform a hemiarch and ascending aortic repair (C and D).
FIGURE 28.18 (A) “Light” arch replacement performing an anastomosis with the proximal descending aorta with the Dacron graft using a running
mattress suture and placement of the stent graft to the descending aorta. The brachiocephalic trunk was perfused via the right subclavian artery, and a
selective perfusion catheter was installed into the left carotid artery for cerebral protection. The left subclavian artery was blocked by a catheter with an
inflatable balloon. (B) Thereafter, a separate prosthesis was anastomosed to the concavity of the remaining arch.
off the intimal tear and leading to quick clot formation and shrinkage of the FL and aortic remodeling [206,207] and
absence of deep hypothermia and associated coagulopathy/hemorrhage. Arch reconstruction is made into an easier, more
“proximal” operation, thus potentially decreasing hemorrhagic complications; complete resection/exclusion of primary
intimal tear; improved recognition and treatment of acute malperfusion [208–211]; decreased cerebral ischemia by avoiding prolonged circulatory arrest; and providing a suitable proximal landing zone if future distal endovascular treatment
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