Art of Operative Techniques

Open reconstruction of thoracoabdominal aortic aneurysms
Yutaka Okita, Atsushi Omura, Katsuaki Yamanaka, Takeshi Inoue, Hiroya Kano, Rei Tanioka, Hitoshi
Minami, Toshihito Sakamoto, Shunsuke Miyahara, Tomonori Shirasaka, Taimi Ohara, Hidekazu Nakai,
Kenji Okada
Division of Cardiovascular Surgery, Department of Surgery, Kobe Graduate School of Medicine, Kobe, Japan
Corresponding to: Yutaka Okita, Professor and Chairman, Division of Cardiovascular Surgery. Department of Surgery, Kobe University Graduate
School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Japan 650-0017. Email: yokita@med.kobe-u.ac.jp.

Technical details of our strategy for reconstructing the thoracoabdominal aorta are presented. Between October1999 and June 2012, 152 patients underwent surgery for thoracoabdominal aortic aneurysms (Crawfordclassification type I =21, type II =43, type III =73, type IV =15). Mean age was 64.6±13.9 years. Sixty-three(41.4%) patients had aortic dissection, including acute type B dissection in 2 (1.2%) and ruptured aneurysms
in 17 (11.2%). Eight (5.3%) patients had mycotic aneurysms, and 3 (2.0%) had aortitis. Emergent or urgent
surgery was performed in 25 (16.4%) patients. Preoperative computed tomography (CT) scan or magnetic
resonance (MR) angiography detected the Adamkiewicz artery in 103 (67.8%) patients. Cerebrospinal fluid
drainage (CSFD) was performed in 115 (75.7%) patients and intraoperative motor evoked potentials wererecorded in 97 (63.8%). One hundred and seven (70.4%) patients had reconstruction of the intercostal
arteries from T7 to L2, 35 of which were reconstructed with the aortic patch technique and 72 with branched
grafts. The mean number of reconstructed intercostal arteries was 3.1±2.5 pairs. Mild hypothermic partial
cardiopulmonary bypass at 32-34 ℃ was used in 105 (69.1%) patients, left heart bypass was used in 4 (2.6%),
and deep hypothermic cardiopulmonary bypass below 20 ℃ was used in 42 (27.6%). Thirty-day mortality
was 9 (5.9%), and hospital mortality was 20 (13.2%). Independent risk factors for hospital mortality were
emergency surgery (OR 13.4, P=0.003) and aortic cross clamping over 2 hours (OR 5.7, P=0.04). Postoperative
spinal cord ischemia occurred in 16 (10.5%, 8 patients with paraplegia and 8 with paraparesis). Risk factors fordeveloping spinal cord ischemic complications were prior surgery involving either the descending thoracic orthe abdominal aorta (OR 3.75, P=0.05), diabetes mellitus (OR 5.49, P=0.03), and post-bypass hypotension <80
mmHg (OR 1.06, P=0.03). Postoperative survival at 5 years was 83.6±4.5%; 5-year survival was 47.5±8.6% in
patients with spinal cord ischemia and 88.9±10.4% in those without spinal cord ischemia.
Key Words: Thoracoabdominal aorta; spinal cord ischemia; intercostal artery reconstruction; postoperative paraplegia
Submitted Aug 04, 2012. Accepted for publication Sep 12, 2012.
DOI: 10.3978/j.issn.2225-319X.2012.09.05
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Introduction
The technical details of our strategy for operating on
thoracoabdominal aortic aneurysms are presented below
with our emphasis on the importance of reconstructing
intercostal and visceral arteries to prevent postoperative
paraplegia, intestinal ischemia, and renal failure.
Patients and methods
Between October 1999 and June 2012, 152 patients© AME Publishing Company. All rights reserved.

underwent surgery for thoracoabdominal aortic aneurysms
at the Kobe University Hospital [Crawford classification
type I=21 (13.8%), type II=43 (28.3%), type III=73(48.0%), type IV=15 (9.9%)]. Mean age was 64.6±13.9
years and 115 (75.7%) patients were male. Sixty-three(41.4%) had aortic dissection, including 2 (1.3%) patientswith acute type B dissection, and 17 (11.2%) had ruptured
aneurysms. Eight (5.3%) patients had mycotic aneurysm,
and 3 (2.0%) had aortitis. Emergent or urgent surgery
was performed in 25 (16.4%) patients. Preoperative

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Okita et al. Reconstruction of thoracoabdominal aorta

A

B

Figure 1 A. The patient is turned into the left semi-posterolateral position with the shoulders rotated rightward 50 degrees and hips rotated
20 degrees. The skin incision follows a rather straight line. The whole thoracoabdominal aorta is exposed through the left 5th or 6th intercostal
space, and a retroperitoneal approach is undertaken; B. The diaphragm is excised circumferentially, leaving a 2 cm peripheral margin

Surgical procedure

Figure 2 Partial cardiopulmonary bypass is initiated through a left
femoral arterial cannula and a right femoral venous cannula, whichis passed to the inferior cavo-atrial junction.

computed tomography (CT) scan or magnetic resonance(MR) angiography detected the Adamkiewicz artery in 103(67.8%) patients. Cerebrospinal fluid drainage (CSFD)
was performed in 115 (75.7%) patients and intraoperative
motor evoked potentials (MEPs) were recorded in 97(63.8%) patients. One hundred and seven (70.4%) patients
had reconstruction of the intercostal arteries from T7
to L2, using the aortic patch technique in 35 patientsand branched grafts in 72 patients. The mean numberof reconstructed intercostal arteries was 3.1±2.5 pairs.
Mild hypothermic partial cardiopulmonary bypass withtympanic temperatures between 32-34 ℃ was used in 105(69.1%) patients, left heart bypass was used in 4 (2.6%),
and deep hypothermic cardiopulmonary bypass withtympanic temperature <20 ℃ was used in 42 (27.6%).
© AME Publishing Company. All rights reserved.

The day prior to the operation, a CSFD catheter is inserted
in the lumbar region. On the day of surgery, both groins areincised and right common femoral vein and left common
femoral artery are exposed in the supine position. Thenthe patient is turned into the left semi-posterolateralposition with the shoulders rotated rightward 50 degrees
and hips rotated 20 degrees (Figure 1A). A catheter forparavertebral nerve block is inserted before skin incision.
The skin incision follows a rather straight line. The wholethoracoabdominal aorta is exposed through the left 5 thor 6th intercostal space, and a retroperitoneal approach isundertaken. The diaphragm is excised circumferentially,leaving a 2 cm peripheral margin (Figure 1B). Transcranial
stimulated MEPs are recorded throughout the operation.
Partial cardiopulmonary bypass is initiated through aleft femoral arterial cannula and a right femoral venous
cannula, which is passed to the inferior caval-atrial
junction (Figure 2). Segmental-staged aortic clamping isliberally used under partial cardiopulmonary bypass. Aortic
segments containing fewer than three pairs of intercostal
arteries are sequentially clamped and opened. The aorta is
initially clamped proximal to the left subclavian artery andacross the mid-descending thoracic aorta (Figure 3).
Next, the aorta is incised between the clamps andbleeding orifices from the bronchial arteries or highintercostal arteries are oversewn (Figure 4A). The proximal
aorta is completely transected and dissected away from thesurrounding esophagus, left vagus nerve, and away thoracic
duct (Figure 4B). A 20 or 22 mm Dacron graft with 8-mm

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Annals of cardiothoracic surgery, Sep 12, 2012

375

Figure 3 The aorta is initially clamped proximal to the leftsubclavian artery and across the mid-descending thoracic aorta andthen the aorta is incised between the clamps

Aside-branches is used. This graft has 4 spatially orientatedbranches for the abdominal visceral arteries. The proximal
anastomosis is performed using a 4-0 monofilament suture(22-mm needle) with Teflon strip reinforcement (Figure 5A).
The edge of the Teflon strip is tightened with a compacting
stitch to prevent suture hole bleeding (Figure 5B). The
descending aorta is then clamped at the T10 level. Before
opening the aorta, the left T8 and T9 intercostal arteries
are exposed and clamped from outside the aorta (Figure 6).
Five minutes after aortic clamping and observing the
MEPs for decreased signaling, the aorta is opened. Backbleeding from the right intercostal arteries is controlled byinserting 2-Fr balloon-tipped catheters into the respective
ostia (Figure 7), in order to prevent spinal cord ischemia
from a steal phenomenon. Patent orifices of intercostal
arteries (no more than two pairs) are then anastomosed toa side hole of the graft as an aortic patch using an inclusion
technique with a 4-0 monofilament suture (17-mm needle)(Figure 8A). Another technique to reattach the intercostal
arteries is through a graft interposition, where several small grafts
connect to the orifices of the intercostal arteries (Figure 8B). Thisis followed by transposing the graft clamp distally to allow
perfusion of the newly anastamosed intercostal arteries(Figure 9). Additional neighboring intercostal arteries arereconstructed and reperfused in the same fashion according
to the findings of the preoperative CT angiogram.
After reconstruction of the intercostal arteries, 30 mg of
Edaravone is routinely administrated to prevent neurologic

B

Figure 4 A. Bleeding orifices from the bronchial arteries or high intercostal arteries are oversewn with monofilatment sutures; B. The
proximal aorta is completely transected and dissected away from the surrounding esophagus, left vagus nerve, and thoracic duct

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Okita et al. Reconstruction of thoracoabdominal aorta

376

A

B

Figure 5 A. A 20- or 22-mm Dacron graft with 8-mm side-branches is used. This graft has 4 spatially orientated branches for the abdominal
visceral arteries. The proximal anastomosis is performed using a 4-0 monofilament suture (22-mm needle) with Teflon strip reinforcement; B.
The edge of the Teflon strip is tightened with a compacting stitch to prevent bleeding from suture holes

Figure 6 The descending aorta is then clamped at the T10 level.

Figure 7 Five minutes after aortic clamping and observing the

Before opening the aorta, the left T8 and T9 intercostal arteries are

MEPs for decreased signaling, the aorta is opened. Back-bleeding

exposed and clamped from outside the aorta

from the right intercostal arteries is controlled by inserting 2-Fr
balloon-tipped catheters into the respective ostia, in order to prevent
spinal cord ischemia resulting from a steal phenomenon© AME Publishing Company. All rights reserved.

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Ann Cardiothorac Surg 2012;1(3):373-380

Annals of cardiothoracic surgery, Sep 12, 2012

A

377

B

Figure 8 A. Patent orifices of intercostal arteries (no more than two pairs) are then anastomosed to a side hole of the graft as an aortic patch
using an inclusion technique with a 4-0 monofilament suture (17-mm needle); B. Another technique to reattach the intercostal arteries isthrough a graft interposition, where several small grafts connect to the orifices of the intercostal arteries

Figure 9 Following the intercostal artery anastamosis, the graft

Figure 10 The infra-renal portion of the abdominal aorta is thenclamp is moved distally to allow perfusion of the newly anastamosed

clamped and opened. The back-bleeding from lumbar arteries isintercostal arteries

controlled similarly to intercostal back-bleeding. The 4 visceralarteries are perfused using 8-Fr size balloon tipped catheters (Fujiphycon®, Tokyo) via a single roller pump at arterial flows of 150-

injury. The infra-renal portion of the abdominal aorta isthen clamped and opened. The back-bleeding from lumbar
arteries is controlled similarly to intercostal back-bleeding.
The 4 visceral arteries are perfused using 8-Fr size balloontipped catheters (Fuji phycon®, Tokyo) via a single roller
pump at arterial flows of 150-200 mL/min (Figure 10).
Upon completion of visceral artery cannulation, rewarming
is initiated. Each visceral artery is individually dissected
to make a button (Figure 11). First, the right renal arteryis anastomosed to one side branch of the graft using a 4-0
monofilament suture. Then, the distal anastomosis between© AME Publishing Company. All rights reserved.

200 mL/min

the graft and the aorta is performed using a 4-0 suture(22-mm needle) and reinforced with Teflon felt. After thisis completed, the buttons of the celiac, superior mesentericartery and left renal artery are anastomosed to side
branches with 4-0 sutures on a 17-mm needle. The inferior
mesenteric artery is often reattached directly to an opening
in the graft using a 5-0 monofilament suture with a 17-mm
needle. After completion of all anastamoses, the patient iswww.annalscts.com

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Okita et al. Reconstruction of thoracoabdominal aorta

Figure 11 Upon completion of visceral artery cannulation,

Figure 12 After completion of all anastamoses, the patient is weaned

rewarming is initiated. Each visceral artery is individually dissectedfrom cardiopulmonary bypass and hemostasis is achieved after

to make a button

protamine is administeredweaned from cardiopulmonary bypass and hemostasis isachieved after protamine is administered (Figure 12).

Comments

Results
Nine (5.9%) patients died within 30 days [Crawfordclassification I =1 (4.8%), II =1 (2.3%), III =6 (8.2%), IV =1(6.7%)], while hospital mortality occurred in 20 (13.2%)
patients [Crawford extent I =3 (14.3%), II =2 (4.7%), III =13(17.8%), IV =2 (13.3 %)]. In emergent and urgent cases,
30-day and hospital mortality rates were 20% and 32%,
respectively. Independent risk factors for hospital mortality
were emergency surgery (OR 13.4, P=0.003) and aortic
cross clamping >2 hours (OR 5.7, P=0.04). Postoperative
spinal cord ischemic complications in 16 (10.5%) patients;
8 patients developed paraplegia and 8 had paraparesis [2(9.5%) in Crawford extent I, 3 (7.0%) in II, 11 (15.1%) in
III, and zero in IV]. In emergent and urgent cases, spinal
cord ischemic complications developed in 12.0%. Risk
factors for spinal cord ischemia were prior surgery involving
the descending thoracic or abdominal aorta (OR 3.75,
P=0.05), diabetes mellitus (OR 5.49, P=0.03) and post-bypass
hypotension <80 mmHg (OR 1.06, P=0.03). Postoperative
survival at 5 years for all patients was 83.6±4.5%. 5-year
survival was 47.5±8.6% in patients with spinal cord ischemic
complications and was 88.9±10.4% in patients without thesecomplications. Freedom from aortic events, such as redo
operation, rupture of residual aneurysm, and false aneurysm
formation, was 91.8±4.3% at 5 years.

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Although the usefulness of extracorporeal circulation
during reconstruction of the thoracoabdominal aorta is
well documented, left heart bypass with a reduced dose ofheparinization (1,2) and repair without cardiopulmonary
bypass altogether (3,4) have been shown to produce
acceptable surgical outcomes. At our institution, we haveprimarily instituted cardiopulmonary bypass insteadof either of these two alternatives as it provides stable
hemodynamic support if pulmonary function deteriorates.
An additional advantage of this technique is that a
cardiotomy suction can be used in case of unexpectedmassive bleeding. Lastly, the benefits of hypothermia on
end-organ protection can be taken advantage of as thepatient’s body temperature is easily controlled throughcore-cooling during the bypass period (5,6).
Revascularization of the intercostal arteries represents animportant technical step during repair of thoracoabdominal
aneurysms. Several surgical techniques have been described,
the most simple of which is an aortic patch anastomosis
to the prosthetic graft. The main advantage of the patch
technique is the reduced number of anastomoses (1).
However, isolated reimplantation of each intercostal arterymight be necessary for larger aneurysms, particularly if
the ostia of the intercostal arteries are widely displaced
from each other. Moreover, it has been reported that whena segment of aortic wall is left in situ to facilitate branch
reconstruction, it may become aneurysmal, particularly

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Annals of cardiothoracic surgery, Sep 12, 2012in patients with Marfan syndrome (7). Dardik et al. (8)reported a prevalence of patch aneurysm of 7.5% in 107
patients who underwent thoracoabdominal aneurysm repair.
Lombardi et al. (9) reported 3 patients with patch aneurysm
among 20 patients who required reoperation after previous
thoracoabdominal aneurysm repair. Kouchoukos et al. (10)reported 2 cases of patch aneurysm in Marfan patients.
The major drawback of the graft interposition technique
is suboptimal patency of the reconstructed grafts whencompared with the patch technique, where almost all
attached intercostal arteries should remain patent. In
our series, early patency of the interpositioned grafts was
only 70% by angiography or CT scan. Moreover, morethan half of the grafts were occluded in patients who had
postoperative paraplegia (11).
Other adjuncts for spinal cord protection played
important roles in the surgical outcomes of thiscohort. The advent of the MR and CT imaging has
facilitated identification of the great radicular artery,
the artery of Adamkiewicz. Yamada et al. (12) firstly
demonstrated the Adamkiewicz artery in the majority ofthe patients with descending or thoracoabdominal aortic
aneurysms. Yoshioka et al. (13) demonstrated several
intercommunicating collateral pathways between the criticalintercostal arteries. These non-invasive imaging techniques
have simplified the surgical procedure to reconstruct
the critical intercostal arteries and neighboring ones.
Additionally, concomitant use of intraoperative transcranialstimulated MEPs of the spinal cord enables detection ofcord ischemia and identifies critical intercostal arteries inreal time (14). Furthermore, CSFD alleviates secondary
compression of the spinal cord due to ischemic edema (15).
Regarding techniques for reconstructing visceralarteries, Carrel et al. (16) reported their technique ofseparate revascularization of the visceral arteries inthoracoabdominal aneurysm repair. Similarly, Safi et al. (17)reported their use of a presewn 4-branched graft for visceralartery reconstruction during thoracoabdominal aortic repair
using a deep hypothermic technique. Visceral protection
has been achieved by separate visceral perfusion with graftflows between 100-200 mL/min. Some reports (18,19) statethat systemic deep hypothermia provides excellent organ
protection; however, deep hypothermia also has potential
disadvantages including a longer cardiopulmonary bypass
time, increased coagulopathy (20), and increased lungdysfunction (21). On the other hand, Coselli et al. (22)emphasized the superiority of infusing cold crystalloid
solution into the renal arteries. We favor, however, perfusing© AME Publishing Company. All rights reserved.

379

viscera rather than infusing cold saline or no perfusion
when the aortic cross clamp time is prolonged. We believethat each button anastomosis facilitates mobilization of the
branches that may improve the postoperative patency rateof visceral arterial anastomoses when compared with thepatency rate following the inclusion technique. Care must
be taken to avoid rotation of the viscera to the right duringreconstruction becasue the visceral arteries, especially theleft renal artery, may kink after subsequent repositioning of
the viscera.
The importance of postoperative pain control cannot
be overemphasized when patients start respiratory
and ambulatory rehabilitation. In such circumstances,paravertebral nerve blockade enables physiotherapy even in
the elderly (23).
Conclusions
Early results of patients who underwent surgery forthoracoabdominal aortic aneurysms, with reconstruction of
the intercostal arteries and using a branched replacement
graft, was satisfactory.
Acknowledgements
We thank Ms. Beth Croce, Illustration Editor, and Dr.
Ashutosh Hardikar, Art of Operative Techniques Section
Editor, for making these highly detailed illustrations.
Disclosure: The authors declare no conflict of interest.
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Cite this article as: Okata Y, Omura A, Yamanaka K, Inoue
T, Kano H, Tanioka R, Minami H, Sakamoto T, Miyahara S,
Shirasaka T, Ohara T, Nagai H, Okada K. Open reconstructionof thoracoabdominal aortic aneurysms. Ann Cardiothorac Surg
2012;1(3):373-380. DOI: 10.3978/j.issn.2225-319X.2012.09.05© AME Publishing Company. All rights reserved.

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