Abstract
Coarctation of the aorta accounts for about 8% of all congenital heart
diseases. Since the first successful case of surgical treatment in 1944
by Crafoord and Nylin1 in Sweden, several surgical techniques
have been employed in the treatment of this anomaly. Here, we review by
illustration the various surgical options in coarctation of the aorta with
emphasis on our preferred technique – the extended resection and end-to-end
anastomosis. Why the extended resection technique? Our experience - and
that of other institutions - has shown that this is a better option in
childhood as it is associated with a lesser degree of recoarctation and
subsequent need for re-intervention.2
MeSH
| Heart defects, congenital |
Child |
Thoracic Surgery |
| Coarctation, aorta |
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Article
Introduction
Over the years, various surgical techniques have been used in patients
with coarctation of the aorta. The choice of procedure has been influenced,
on one hand, by the trend at the time of presentation and on the other
hand, by the presence of associated cardiac anomalies. In this article,
we review the common techniques before dwelling on the one mostly used
in recent years.
Patient position and surgical approach
In most cases, the surgical approach is through a left thoracotomy
performed usually in the fourth intercostal space. The patient is placed
in a lateral position with the left side up (Fig.1). A curved incision
is made, starting at the anterior axillary line and extending posteriorly
just below the tip of the scapula where it curves upward to end midway
between the vertebral column and scapula over the anteroinferior margin
of the trapezius muscle (Fig. 2). This region of the trapezius is divided
as well as the latissimus dorsi muscle. The serratus anterior is mostly
preserved while the fourth intercostal space is identified and opened.
The rib spreader is inserted and opened in stages to avoid rib fractures(Fig.
3) The lung is retracted anteriorly and the mediastinal pleura opened over
the aorta downward for about 3 cm below the coarctation site and then upward
across the entire left subclavian artery. Stay sutures are placed along
each side of the pleural incision. The left superior intercostal vein is
ligated and divided. The proximal left subclavian artery, the distal transverse
arch and the aortic isthmus are dissected and tapes may be placed around
them. To minimize the possibility of damage to the thoracic duct, all dissection
is done close to the aorta. When present, "Abbott’s artery" which arises
from the medial aspect of the isthmus, should be ligated and divided. The
ligamentum arteriosum or ductus is also ligated and divided. Care must
be exercised to avoid injury to enlarged intercostal arteries.
Figure 1: Patient position (left lateral approach)
Figure 2: A curved incision is made on the left thorax
Figure 3: Left lateral thoracotomy
Figure 4: Mobilization of the aorta and other structures
Figure 5: A. A view of the site of coarctation after mobilization
of key structures. Notice the 6-0 prolene suture around the ductus for
ligation. B: In the extended resection technique, the transverse arch is
also dissected to enable wider mobility and resection
Surgical techniques
With the patient’s nasopharyngeal temperature at about 33°C, aortic
clamps are placed above and below the site of coarctation. The position
of the vascular clamp, proximal to the site of coarctation, will depend
on the site of coarctation and the type of procedure chosen (Fig. 6). It
may be necessary to clamp some intercostal arteries using "bull-dog" clips,
or tourniquettes.
Resection and end-to-end anastomosis – first developed by Gross
et al,3 this technique is still widely used especially in older
children and adults. After sufficient mobilisation of the aortic arch and
placement of the vascular clamps, the aorta is transected proximal to the
coarctation at a level that ensures removal of any narrowed portion of
the isthmus as well as the coarctation. A similar transection is made below
the site of coarctation. With the aortic clamps held by the second assistant,
the end-to-end anastomosis is begun at the deep angle.
Figure 6: Position of the aortic clamps and resection of the
coarctation site
Figure 7: Resection and end-to-end anastomosis. Dotted lines
indicate the points of resection. IA – inominate artery, LCC – left common
carotis LS – left subclavian artery DA – ductus arteriosus
Subclavian flap angioplasty – also known as the Waldhausen4
procedure after its author, it involves transection of the subclavian
artery and its subsequent use as a flap to enlarge the site of coarctation.
Figure 8: The subclavian flap technique. The left subclavian
artery is transected (B) and used as a flap to enlarge the site of coarctation
(C)
Prosthetic patch aortoplasty- this technique was first used
by Vosschulte5 in 1957 and entails the use of a prosthetic patch
to enlarge the site of coarctation.
Figure 9: The prosthetic patch aortoplasty. A dacron patch is
used to enlarge the site of coarctation. The ducuts is ligated and transected
Extended resection and end-to-end anastomosis. Amato et al6
first published the description of this technique in 1977. Unlike in the
first procedure described above, the proximal incision in this case is
extended to the under-surface of the aortic arch (Fig. 10) enabling a much
larger anastomosis between the proximal and distal parts.
Figure 10: A. Resection of the coarctation lesion B. Further
resection of the distal end may be necessary. C. The proximal incision
is extended to the under-surface of the transverse arch (extended resection)
Figure 11: State after resection
Figure 12: The aortic clamps are approximated and sutures
placed beginning from the deep angle.
Figure 13: The anastomosis is completed by suturing the superior
ends.
Figure 14: Complete anastomosis. The clamps are released - first,
the distal and then the proximal clamp; haemostasis is secured
Figure 15: A line drawing of the extended resection and end-to-end
anastomosis technique
Comparison of surgical techniques –our experience
The choice of a particular surgical technique for the treatment of
aortic coarctation is determined not only by the type of coarctation lesion
but also by factors such as the presence of associated anomalies, the age
at presentation and not the least, the surgeon’s preference. It is therefore
very difficult to identify an "ideal" surgical technique. However, objective
comparisons can be made based on such determinants as the rate of recoarctation
and freedom from re-intervention. We conducted a study of 201 patients
undergoing surgery for coarctation of the aorta over a period of ten years.
139 of these patients had simple or isolated coarctation, 35 had coarctation
with ventricular septal defects (VSD), while 27 patients had coarctation
with complex intra-cardiac anomalies including hypoplastic left heart syndrome,
transposition of the great arteries (TGA) and Shone syndrome. On the whole,
19 cases of recoarctation were recorded, representing 10% of all operated
patients. Our results showed that patients who underwent resection and
end-to-end anastomosis were at a greater risk of recoarctation than were
those who underwent other surgical procedures (P = 0.01). Of the 19 cases
of recoarctation, 15 (79%) were patients who underwent resection and end-to-end
anastomosis, 2 had extended resection and end-to-end anastomosis while
the remaining 2 patients underwent subclavian flap angioplasty and total
arch reconstruction respectively. None of the patients who underwent patch
aortoplasty had recoarctation. A further look at the cases of recoarctation
showed that 12 of the 19 patients were neonates. 10 of these neonates were
treated using resection and end-to-end anastomosis, 1 by extended end-to-end
anastomosis, while 1 underwent total arch reconstruction. Hence, the use
of resection and end-to-end anastomosis in neonates is associated with
a higher risk of recoarctation (P<0,0001) than the use of extended resection
and end-to-end anastomosis. Details of our findings have been previously
published.8,9
Postoperative complications
In our series, only few complications attributable to surgery were
recorded. These include: postoperative bleeding in 4 (2%) patients, phrenic
nerve injury in 3 (1.5%), Horner’s syndrome in 1(0,5%) and chylothorax
in 4 (2%). We did not record any case of paraplegia or CNS damage due to
aortic cross-clamping. Protective measures such as cooling the body temperature
to about 33° C and maintaining a distal
blood pressure of over 45mmHg during cross-clamping were employed in all
patients. The duration of aortic cross clamp in most of our cases was less
than 20 minutes.
References:
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Crafoord C, Nylin G. Congenital coarctation of the aorta and its surgical
treatment J Thorac Surg 1945;14:347
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Backer CL, Mavroudis C, Zias EA, Amin Z, Weigel TJ. Repair of Coarctation
with Resection and extended End-to-End Anastomosis. Ann Thorac Surg 1998;66:1365-1371
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Gross RE. Surgical correction of coarctation of the aorta. Surgery 1945;18:673
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Waldhausen JA, Nahrwold DL. Repair of coarctation of the aorta with a subclavian
flap. J Thorac Cardiovasc Surg 1966;51:532
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Vosschulte K. Surgical correction of the aorta by an "isthmus plastic"
operation. Thorax 1961;16:338
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Amato JJ, Galdieri RJ, Cotroneo JV. Role of extended aortoplasty related
to the definition of coarctation of the aorta. Ann Thorac Surg 1991;52:615-20
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Kirklin JW, Barrat-Boyes BG. Coarctation of the aorta and aortic arch interruption.
In: Cardiac Surgery, 2nd ed. Kirklin JW, Barrat-Boyes BG (editors)
New York: Churchill Livingstone 1993:1263-1325
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Omeje IC, Valentikova M, Kostolny M, Sagat M, Nosal M, Siman J, Hraska
V. Improved patient survival following surgery for coarctation of the aorta.
Bratisl Lek Listy. 2003;104:73-77
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Omeje IC, Kaldararova M, Sagat M, Sojak V, Nosal M, Siman J, Hraska V.
Recoarctation and patients’ freedom from re-intervention – a study of patients
undergoing surgery for coarctation of the aorta at the Department of Cardiac
Surgery of the Children’s University Hospital, Bratislava. Bratisl Lek
Listy 2003; 104:115-119
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Contact information
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Dr. IC Omeje
Department of Cardiac Surgery
The Slovak Children’s Heart Center
Limbova 1
833 51 Bratislava
Slovakia.
Tel: +421 (2) 59371327
Fax: +421 (2) 54775766
Omeje@yahoo.co.uk
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