| The technique of resection with extended
end-to-end anastomosis was originally described in 1977 by Dr. Joseph
Amato, who operated on four patients with hypoplasia of the distal transverse
arch. It was his concept to create the anastomosis underneath the left
carotid artery. There are several concepts that make this an ideal operation
for coarctation of the aorta: (1) all coarctation tissue with uncertain
potential for future growth is completely resected. (2) The left subclavian
artery is preserved, avoiding potential arm ischemia or growth disorders.
(3) This procedure simultaneously addresses and corrects hypoplasia of
the transverse arch, the distal aortic arch, and the aortic isthmus. (4)
The technique avoids use of prosthetic material, limits the potential
for aneurysm formation, and preserves normal vascular anatomy. (5) Paraplegia
has not been reported as a complication of resection with extended end-to-end
anastomosis despite the ligation of multiple collaterals in several major
series, including one of over 300 patients. (6) This technique has been
modified to the radically extended end-to-end anastomosis that involves
occluding even a portion of the innominate artery during the procedure.
Drs. Mello and Kopf have put together for us a concise and very complete
review of the technique of resection with extended end-to-end anastomosis.
This operation, I believe, is the current procedure of choice at many
institutions for infantile aortic coarctation, particularly for children
with transverse arch hypoplasia. We began using this technique at Childrens
Memorial Hospital in 1991 and have now performed this operation in over
100 patients.
This Experts Techniques Section illustrates the
procedure being performed through a left thoracotomy approach. Of course,
this same operation may be performed through an anterior approach using
a median sternotomy and cardiopulmonary bypass for patients with associated
intracardiac lesions, such as ventricular septal defect, which are to
be repaired at the same time.
My technique for this operation is almost identical
to that presented in these illustrations.
Several minor variations in technique that I would like to note:
Anesthesia/Monitoring/Positioning
- I have frequently used the fourth intercostal
space and find that the mobilization of the head vessels allows the
arch to come down for the anastomosis.
- I do not have experience with the use of a right
axillary artery catheter.
- I agree completely with aggressive mobilization
of the entire arch, its branches, and the descending aorta. This allows
a tension-free anastomosis.
- I agree completely with the controlling of any lymphatic
vessels. One technical pitfall is to be careful of the thoracic duct.
This tends to run in the posterior pleura along the spinal column. I
have frequently noted the thoracic duct crossing the subclavian artery
superiorly and sometimes can see this as a clear vessel between 2-4
mm in diameter. Any lymphatic leak should be controlled either with
clips or figure-of-eight polypropylene sutures in order to prevent a
postoperative chylothorax.
Ductal Ligation
- I have not administered heparin to my patients for
this operation. I have not seen in any patient stroke or evidence of
thrombus distally such as bowel infarction or renal insufficiency. Not
using heparin, the anastomosis rarely bleeds at all.
Positioning of Clamps
- I have found that use of the small Castaneda
clamp effectively controls the left subclavian and left carotid arteries
along with the transverse arch using a single clamp. I have not found
it necessary to use the neurovascular clamps illustrated in these techniques.
I would emphasize the importance of the clamp position though to allow
adequate flow through the innominate artery and the importance of monitoring
at all times the right radial arterial waveform with great care taken
to the clamp position. Excessive tension on the clamp can cause occlusion
of the innominate artery, which could lead to fairly quick cardiac dysfunction.
- I prefer to ligate the intercostal collateral vessels
with 4-0 silk sutures rather than use hemoclips. Occasionally, with
hemoclips, I have had experience with them coming off when they are
retracted against or brushed against during the procedure.
Anastomosis
- I have used an identical suture technique
to that described in this manuscript.
- Another technical pitfall is to make sure the alignment
of the descending thoracic aorta and the undersurface of the transverse
arch are without rotation. Any rotation of this anastomosis can cause
a kinking of the relatively small remaining transverse aortic arch and
lead to a noticeable stenosis immediately after the clamps are released.
Variation with Exclusion of aortic Isthmus
- The technique illustrated for the hypoplastic transverse
isthmus is also an excellent technique and there is no reason to preserve
that tiny isthmus if it is not going to contribute to the anastomosis.
Closure
- In many neonates I have been unable to close the
parietal pleura because of the tenuous nature of the pleura and the
swelling in the area following the procedure. I have not found this
to be a problem with bleeding postoperatively. I have in fact had some
patients in whom I attempted to close the pleura and noticed a diminution
in the umbilical artery pulse and have then left the pleura open.
I have put together a small sample of the results with
resection with end-to-end anastomosis from several centers around the
world. Conte et al (1995) reported 307 patients with a 7% operative mortality
and 9% recoarctation incidence. Van Heurn (1994) reported 77 patients
with a 6% operative mortality and 11% recoarctation rate. In my review
of the world literature a cumulative group of patients undergoing resection
with extended end-to-end anastomosis totaled 608 patients with a 10% overall
operative mortality and a recoarctation rate of 8%.
References
- Conte S, Lacour-Gayet F, Serraf A, et al: Surgical
management of neonatal coarctation. J Thorac Cardiovasc Surg 1995;109:663-674.
- van Heurn LWE, Wong CM, Spiegelhalter OJ, et al:
Surgical treatment of aortic coarctation in infants younger than 3 months:
1985 to 1990. Success of extended end-to-end arch aortoplasty. J Thorac
Cardiovasc Surg 1994;107:74-85.
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