Ann Thorac Surg 2001;72:611-613
© 2001 The Society of Thoracic Surgeons
Case report
Repair of coarctation in a right-sided circumflex retroesophageal aortic arch
Timothy W. Pettitt, MDa,
Joseph Caspi, MDa,
Satinder K. Sandhu, MDb,
Kenneth J. Ward, MDc,
R. Lester Hixon, MDc
a Division of Cardiothoracic Surgery, Louisiana State University, New Orleans, Louisiana, USA
b Division of Pediatric Cardiology, Louisiana State University, New Orleans, Louisiana, USA
c Department of Radiology, Children’s Hospital, New Orleans, Louisiana, USA
Accepted for publication August 17, 2000.
Address reprint requests to Dr Pettitt, Division of Cardiothoracic Surgery, Children’s Hospital, 200 Henry Clay Ave, New Orleans, LA 70118
e-mail: twpettitt{at}aol.com
 |
Abstract
|
|---|
We describe an unusual case of a 3-month-old infant with normal cardiac situs and coarctation of the aorta occurring proximal to the right subclavian artery in the presence of a right-sided retroesophageal circumflex aortic arch and aberrant left subclavian artery. Preoperative evaluation with magnetic resonance imaging and conventional aortography led us to surgically approach this lesion through a right thoracotomy with a successful outcome.
|
Introduction
|
|---|
The majority of right aortic arches will descend on the right side of the spine with either mirror-image branching of the brachiocephalic vessels or an aberrant left subclavian artery arising from the proximal descending aorta behind the esophagus. However, some right aortic arches will cross the midline behind the esophagus to descend on the left side of the spine, a variant known as the right circumflex retroesophageal aortic arch [1]. It is common in cases of circumflex arch for the arch to be elongated and extend to a higher than usual level in the thorax [2]. An extreme example of this would be a right cervical aortic arch producing a pulsatile mass in the right neck. The terminal portion of cervical arches usually crosses the midline behind the esophagus to descend on the contralateral side of the spine similar to that seen with circumflex arches. The branching patterns of the brachiocephalic vessels can be quite variable in cervical or circumflex arches. The location of the ductus or ligamentum arteriosus further complicates the anatomy and may complete a vascular ring around the trachea and esophagus, which can lead to compressive symptoms such as stridor, wheeze, or feeding difficulties.
A right aortic arch is uncommon in the setting of an otherwise normal heart. Coarctation of a right aortic arch is even more rare. A recent review of the literature identified 26 patients with coarctation of a right aortic arch in the presence of normal cardiac situs; 6 of these were right cervical arches [3]. We herein report a case of an infant with coarctation of a right circumflex retroesophageal aortic arch and aberrant left subclavian artery.
The patient was a 3-month-old infant whose prenatal history was remarkable for intrauterine growth retardation and fetal distress at 37 weeks requiring emergent delivery by cesarian section. At birth, the patient weighed 1.7 kg and required several days of mechanical ventilation for respiratory distress and was treated for possible sepsis. An echocardiogram (ECHO) revealed a bicuspid aortic valve and depressed ventricular function with cardiomegaly seen on chest x-ray film. Follow-up ECHO, 2 months later, revealed the presence of an aortic coarctation with a 70 mm Hg peak pressure gradient, and she was referred for surgical correction.
On presentation to our facility, the infant weighed 3.6 kg and had a diminished right brachial pulse as well as absent left brachial and femoral pulses. There was no history of feeding difficulties or stridor, and the infant had been gaining weight appropriately. Repeat ECHO suggested a right aortic arch without the typical appearance of coarctation distal to the left subclavian artery. To help further delineate the anatomy, a magnetic resonance imaging (MRI) (Fig 1) was performed that confirmed the presence of a right aortic arch that crossed the midline posterior to the esophagus and descended on the left side of the spine. The arch gave off four branches. The first, most proximal, branch was the left common carotid artery, followed by the right common carotid artery, right subclavian artery, and finally, the left subclavian artery which came off near the junction of the terminal retroesophageal circumflex arch with the proximal descending thoracic aorta. There appeared to be a tight coarctation of the aortic arch just proximal to the takeoff of the right subclavian artery directly lateral and to the right of the esophagus. Luminal continuity was confirmed by conventional aortography with a 40 mm Hg peak gradient across the coarctation. The aortogram also nicely demonstrated elongation and cephalad extension of the arch to nearly the thoracic inlet as well as its circumflex component crossing behind the esophagus (Fig 2). The location of the ductus arteriosus or its remnant could not be ascertained by either study, however, we suspected the presence of a left ligamentum arteriosus to the left subclavian artery completing a vascular ring.
View larger version (138K):
[in this window]
[in a new window]
|
Fig 1. Magnetic resonance imaging demonstrating right-sided ascending aorta (a) and circumflex aortic arch (b) passing behind the esophagus to descend on the left side. Notice the kink (arrow) in the aorta corresponding to the region of the coarctation and its relationship to the trachea (e). (c) Right subclavian artery; (d) left subclavian artery.
|
|
View larger version (61K):
[in this window]
[in a new window]
|
Fig 2. (A) Frontal aortogram demonstrating the elongated circumflex aortic arch and four-vessel branching pattern. (B) Lateral aortogram demonstrating area of coarctation (arrow).
|
|
Through a right thoracotomy, the coarctation was identified at the apex of the arch just proximal to the right subclavian artery as it turned abruptly to descend obliquely behind the esophagus. Of interest, the recurrent laryngeal nerve encircled the aorta at the obstruction. The aorta was mobilized, coarctectomy performed and an end-to-end anastomosis performed using the base of the right subclavian artery. Ascending aorta pressure by direct needle puncture was equal to the femoral arterial catheter pressure after repair. Even if there was a complete vascular ring, the trachea and esophagus did not appear significantly compressed after the repair. Aside from some moderate hypertension, the patient went on to have an uneventful recovery. Follow-up ECHO, 1 month postoperatively, revealed no significant gradient across the repair, and the child is doing well and gaining weight.
|
Comment
|
|---|
Coarctation of the aorta in the presence of a right circumflex arch is extremely rare and poses some challenging diagnostic and therapeutic dilemmas. ECHO alone is often all that is needed to diagnose a typical coarctation and proceed with surgery. However, in this atypical case, MRI was extremely helpful in defining the relationship of the aortic arch and coarctation to the neighboring mediastinal structures, specifically the trachea, esophagus, and spine. We could have proceeded with surgery based on the results of the MRI alone, however, we felt more comfortable with the additional information gained from aortography. MRI is becoming increasingly more popular in the diagnosis and evaluation of children with coarctation, vascular rings, and other aortic arch anomalies [4, 5].
Perhaps, the most important question raised by this case is how best to surgically approach this lesion. Most would agree that a right thoracotomy would give the surgeon the best, unobstructed view given the location of the coarctation in relation to the spine and esophagus. Some authors advocate using a left thoracotomy to approach coarctations even in the presence of a right aortic arch because it allows division of the ligamentum [6]. In this case, it would have been impossible to perform the coarctectomy and reanastomosis through a left thoracotomy. Although mobilization of the aorta about the coarctation was limited because of the retroesophageal circumflex aorta and aberrant left subclavian, we achieved a satisfactory result. If the patient had symptoms of a vascular ring preoperatively, then bilateral thoracotomies would have been warranted, one to repair the coarctation and the other to divide the ligamentum. Arguably, another option favored by some [7] would be to approach the defect through a median sternotomy, perform the coarctectomy and reanastomosis, and divide either the ligamentum or left subclavian artery to relieve the vascular ring. However, in the asymptomatic patient, without evidence of tracheoesophageal compression, is it absolutely necessary to divide a suspected vascular ring? We strongly considered these options and decided that this patient’s main problem was coarctation and that the safest approach with the best chance of achieving a technically perfect anastomosis was through a right thoracotomy. Because she was asymptomatic preoperatively, and the trachea and esophagus did not appear to be compressed at the time of surgery, the decision was made not to pursue division of the probable vascular ring. She weaned from the ventilator without difficulty and an elective barium swallow performed before the infant went home showed a prominent posterior esophageal indentation from the circumflex aorta as expected, however, there was no obstruction. She will certainly require close surveillance, as symptoms of a vascular ring may become manifest later in life.
In summary, the management of patients with unusual arch anatomy and coarctation needs to be individualized based on their symptoms and radiographic picture. As our experience and level of comfort with MRI improve, we anticipate performing fewer catheterizations for patients with arch anomalies and coarctation. The laterality of the descending aorta and brachiocephalic branching pattern as well as the presence of a vascular ring need to be taken into account when deciding on the surgical approach to these patients.
|
References
|
|---|
-
D’Cruz I.A., Cantez T., Namin E.P., Licata R., Hastreiter A.R. Right-sided aorta. Part II. Right aortic arch, right descending aorta, and associated anomalies. Br Heart J 1966;28:725-739.
-
Sissman N.J. Anomalies of the aortic arch complex. In: Adams F.H., Emmanouilides G.C., eds. Moss’ heart disease in infants, children and adolescents. Baltimore: Williams and Wilkins, 1983:199-215.
-
McElhinney D.B., Tworetzky W., Hanley F.L., Rudolph A.M. Congenital obstructive lesions of the right aortic arch. Ann Thorac Surg 1999;67:1194-1202.[Abstract/Free Full Text]
-
Burrows P.E. Magnetic resonance imaging of the aorta in children. Semin Ultrasound CT MR 1990;11:221-233.[Medline]
-
Azaro K.S., Pearl R.H., Hoffman M.A., Zurcher R., Edwards F.H., Cohen A.J. Vascular ring: does magnetic resonance imaging replace angiography?. Ann Thorac Surg 1992;53:882-885.[Abstract]
-
Ad N., Vidne B.A. Coarctation of the aorta with right aortic arch: surgical technique and new classification. Ann Thorac Surg 1999;67:1125-1129.[Abstract/Free Full Text]
-
McElhinney D.B., Thompson L.D., Weinberg P.M., Jue K.L., Hanley F.L. Surgical approach to complicated cervical aortic arch: anatomic, developmental, and surgical considerations. Cardiol Young 2000;10:212-219.[Medline]
This article has been cited by other articles:
|
|
|
|
 
P. M. Patel, H. L. Bartlett, T. Scholz, J. Burzynski, D. M. Behrendt, and H. M. Burkhart
Norwood modification in a patient with hypoplastic left heart and a right aortic arch.
J. Thorac. Cardiovasc. Surg.,
October 1, 2007;
134(4):
1065 - 1066.
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
