Aortic obstructions in infants and children

Aortic Obstructions in Infants and Children Surgery for Complex Aortic Coarctation

STEVEN J. HOFF, M.D. JAMES R. STEWART, M.D. HARVEY W. BENDER, JR., M.D. Department of Cardiac and Thoracic Surgery

Vanderbilt University School of Medicine Nashville, Tennessee

ABSTRACT Coarctation of the aorta is a constellation of aortic obstructive lesions that may occur from the ascending to descending abdominal aorta. It is frequently associated with a variety of other obstructive and nonobstructive intracardiac defects. A strategy for the management of these lesions is presented encompassing the indications for operation, preoperative management, and operative techniques, options, and results. Keywords: coarctation of the aorta, complex; surgery The anatomic manifestations of coarctation of the aorta cover a broad spectrum, from minimal obstruction to luminal atresia. Coarctation may occur anywhere from the ascending aorta to the abdominal aorta, but it occurs typically as a discrete narrowing at the level of the ductus arteriosus. Coarctation can be associated with a variety of complex obstructive lesions, including tubular hypoplasia of the aortic arch, left ventricular outflow tract obstruction, and left ventricular hypoplasia (hypoplastic left heart syndrome) as well as other more common nonobstructive congenital intracardiac defects. Patients with associated lesions often present early in life with congestive heart failure Address correspondence to James R. Stewart, M.D., The Vanderbilt Clinic, Room 2986,130121st Avenue South, Nashville, TN 37232-5734.

and require urgent operation. Continuity of the lumen of the aorta above and below the coarctation distinguishes it from interrupted aortic arch, where the proximal aorta and site of interruption are usually separated. We present our rationale for the operative management of complex aortic coarctation and associated lesions with results obtained over >20 years of experience.

HISTORY Morgagni first described a case of aortic coarctation at autopsy in 176O.l Later Paris2 described more completely the pathologic features of the defect. In a 1903 review by Bonnett,3 aortic coarctation was classified into “adult” and “infantile types.” Later this was revised by Keith et a1.4 into the more commonly used classifications of preductal (proximal to the ductus arteriosus) and postductal (distal to the ductus or ligamenturn arteriosum) coarctation. Although early autopsy studies defined. the spectrum of aortic coarctation in adults and children,5,6 it was only in the 1950s that coarctation was recognized as a cause of death in infants.7p8 Research into surgical correction of aortic coarctation began in animal models in the 1930s. In 1944, Blalock and Park9 published their experiences with the left subclavian artery turned onto the aorta. In 1945, Gross and HufnageliO provided a detailed Prog Pediatr Cardiol 1994; 3(2):62-72 Copyright 0 1994 by Butterworth-Heinemann

Surgery for Complex Aorfic Coarctafion

description of the use of end-to-end anastomosis for correction-of aortic coarctation. They noted the surgical complication of paraplegia in some experimental animals and its prevention with spinal cooling. The first repair of coarctation of the aorta was performed by Crafoord and Nylini’ in Sweden in 1944. In the United States, the first repair was performed by GrosP in 1945. Repair in an infant was attempted unsuccessfully in 1950~ and accomplished successfully in 1951 by use of an end-to-end anastomosis.13 In 1966, Waldhausen and Nahrwo1d14 introduced subclavian flap aortoplasty, a technique now widely accepted for neonates. In 1975, it was demonstrated that prostaglandin E, (PGEi) infusion maintains the clinical improvement produced by dilatation of the ductus arteriosus and maintenance of ductal flow, thus stabilizing severely ill neonates. Surgical correction is performed in a hemodynamically stable patient, without acidosis, and has led to substantial improvements in outcome.15-‘7 In a series of infants undergoing repair of aortic coarctation, Hallman et al.lB in 1967 described the use of pulmonary artery banding in those patients with an associated ventricular septal defect. In a review published in 1969, Tawes et a1.i9 described the increased mortality rate and recurrence of obstruction seen in patients with preductal coarctation and hypoplastic aortic arch. This problem was further characterized by Hermann et al.*O in 1978. In 1977, Amato et al.21 presented a method for enlarging the distal transverse arch in infants with hypoplasia of the aortic arch.

COMPLEX AORTIC COARCTATION The prevalence of isolated coarctation of the aorta with or without a patent ductus arteriosus is - 401 100,000 live births.22 As an isolated lesion, coarctation occurs in 82% of patients when all age-groups are considered; it is associated with a hemodynamitally significant ventricular septal defect in 11% and more severe intracardiac anomalies in 7%. As the age of presentation falls, the prevalence of isolated aortic coarctation diminishes. In patients
63

our experience shows that isolated coarctation is present in only 22% of patients (J. R. Stewart, S. J. Hoff, W. H. Merrill, H. W. Bender, Jr., unpublished data). This is similar to previously published reports of neonates with prevalence rates of 21% and 35 % .22-23 Uniform, symmetric narrowing of the transverse aortic arch with or without the classic shelflike membranous obstruction at the level of the isthmus has been termed tubular hypoplasia.24 Some authors believe that this lesion is associated with other congenital intracardiac anomalies affecting fetal and postnatal left ventricular blood flow (mitral valve disease; left ventricular hypoplasia; subvalvular, valvular, or supravalvular aortic stenosis) and regard the variants as a form of hypoplastic left-heart syndrome or Shone’s complex.22 In our experience with 124 neonates who required coarctation repair in the first month of life, transverse aortic arch hypoplasia was seen in 38% and left ventricular hypoplasia was present in 8% (J. R. Stewart, S. J. Hoff, W. H. Merrill, H. W. Bender, Jr., unpublished data). Bicuspid aortic valve with or without obstruction is present in 19% to 21% of children with coarctation of the aorta24 (J. R. Stewart, S. J. Hoff, W. H. Merrill, H. W. Bender, Jr., unpublished data). The prevalence of these lesions with complicated aortic coarctation is not well studied, but it is certainly much lower as the age of patient presentation and operation increases. The prevalence of associated intracardiac anomalies that adversely affect the clinical course of the patient is higher in children who require operative repair earlier in life (Table 1). In those patients operated on during the first year of life, the prevalence of a ventricular septal defect is between 30% and 37% .22,23If operation is required in the first month of life, the prevalence increases to 38 % to 40 % 22 (J. R. Stewart, S. J. Hoff, W. H. Merrill, H. W. Bender, Jr., unpublished data). Similarly, more complex intracardiac defects are present in as few as 5% of children requiring repair in the first year of life.= A recent report indicates that, with aging, the prevalence of complex associated intracardiac abnormalities in infants undergoing repair of aortic coarctation in the first year of life rose from 10% in the 1960s to 38% in the 1980~.~ The prevalence rates of specific intracardiac lesions associated with aortic coarctation are presented in Table 1. In general, the prevalence rates of most lesions are in-

Progress in Pediattic Cardiology

64

TABLE

1. Associated Intracardiac Anomalies KirklirP

n

Age at operation Lesion PDA VSD only Complex anomaly Transposition + VSD Double outlet LV Aortic stenosis/insufficiency Mitral stenosis/insufficiency Hypoplastic left heart Single ventricle Subaortic stenosis Tricuspid atresia AV canal Truncus arteriosus Anomalous pulmonary venous

Vanderbilt *

94

124



% 36 34 30 9 5 8 6

% 22 38 40 17 10

1

8 5 8 5 3 2 4

1

2

3

1

connection

l J. R. Stewart, S. J. Hoff, W. H. Merrill, H. W. Bender, Jr., unpublished data.

versely related to the age of the patient at presentation and surgical repair.

Indications

SURGERY for Operation

Isolated asymptomatic aortic coarctation should be repaired on an elective basis to prolong adult survival and avoid upper extremity hypertension.22 Asymptomatic or minimally symptomatic children with isolated coarctation should be operated on before 5 years of age because of a lower incidence of postoperative hypertension and late cardiovascular complications.26,27 In symptomatic patients, the timing of operation depends largely on the severity of symptoms and the ease with which they can be palliated medically. The complexity of the obstruction and the presence of associated intracardiac anomalies also influences the timing of operative intervention. Coarctation with a ventricular septal defect usually presents in infancy with severe congestive heart failure and requires stabilizing treatment and urgent operation. If the ventricular septal defect is small with a low-volume left-to-right shunt, spontaneous closure of the septal defect is common after repair of the coarctation.28 If significant shunting results in persistent postoperative congestive heart failure, then closure of the ventricular septal defect

can be performed. 29Infants with very large ventricular septal defects, multiple ventricular defects, or large apical muscular defects usually have severe congestive heart failure, and spontaneous closure is uncommon. Open repair of these lesions is difficult and may require right or left ventriculotomy. In these patients, strong consideration should be given to pulmonary artery banding at the time of coarctation repair.29*30 In these sick neonates, clinical improvement is usually dramatic, thus allowing for a delayed repair of the ventricular septal defect at 3 to 6 months of age with excellent results.3’ One-stage repair of aortic coarctation and ventricular septal defect has been reported with good results,32-” although adequate exposure of the coarctation site can be difficult. Indications for operative repair of coarctation associated with more complex intracardiac lesions are similar to those for associated ventricular septal defect. The patients generally present as neonates with profound congestive heart failure or cyanosis. Our approach has been that of a staged repair, with pulmonary artery banding at the time of coarctation repair and later elective repair of complex intracardiac malformations. Median stemotomy with one-stage repair of more complex intracardiac lesions has been described.33s” Indications for concomitant repair of tubular hypoplasia of the transverse aortic arch remains controversial. Several authors have reported excellent results,23,35,36and others have shown that this area may grow after simple repair of the more discrete coarctation.22,37 Myers et a1.38 recently reported growth of the transverse aortic arch after subclavian flap aortoplasty, particularly in neonates undergoing repair in the first month of life. Our approach has been to repair the discrete coarctation and limit repair of the hypoplasitc arch to those who have persistent postoperative obstruction. Peroperative

Management

Infants with symptomatic aortic coarctation usually present in the first month of life with severe congestive heart failure. Most respond favorably to PGEr infusion to maintain ductal patency and improve distal aortic blood flo~.~~ Digoxin and diuretic therapy are also useful in preoperative management for clinical stabilization of the sick neonate. Cardiac catheterization can then be performed to determine the precise location and sever-

Surgery for Complex Aortic Coarctation

65

ity of left ventricular outflow tract obstruction, the presence of associated intracardiac anomalies, and the degree of intracardiac shunting. Metabolic acidosis should be aggressively corrected. Urgent repair is accomplished after stabilization and evaluation have been completed. Occasionally, anticongestive and prostaglandin therapies are not effective in improving systemic perfusion, and catheterization and operation are necessary in a matter of hours. Repair

of Complex

Aortic

Coarctation

The most common form of complex coarctation involves tubular hypoplasia of the aortic arch and/ or isthmus just proximal to the coarctation. This stenotic segment of aorta varies in length and can be quite long and virtually atretic. The operative approach, similar to that for repair of uncomplicated coarctation, uses a left posterolateral thoracotomy through the fourth intercostal space. The pleura is incised over the proximal descending thoracic aorta, and the arch and its branches are mobilized. Complete mobilization of intercostal arteries is particularly important for repair of complex aortic coarctation, because extra length is often needed to create a tension-free anastomosis. The ductus is divided. Several techniques have been described for repair of hypoplastic arch or isthmus associated with coarctation, including extended end-to-end anastomosis, subclavian flap aortoplasty (classic and reversed), patch aortoplasty, and bypass grafting. The indications for each of these techniques depends on the age of the patient, the circumstances surrounding operation or reoperation, and the anatomy of the lesion. Extended

End-to-End

Anastomosis

After the hypoplastic segment of arch or isthmus is identified and completely mobilized (Figure 1),23 vascular occlusion clamps are placed proximally across the transverse arch and left subclavian artery. An incision is made proximally across the aorta just distal to the origin of the left subclavian artery. This incision is made in the frequently dilated aortic segment distal to the coarctation. It may need to be made at an angle to provide sufficient diameter to match the incision in the inferior transverse arch. The anastomosis is then performed by use of continuous 7-O polypropylene suture. If

FIGURE

1. Extended end-to-end anastomosis.

the hypoplastic segment includes the origin of the left common carotid or subclavian artery, the left subclavian artery may be divided and the proximal incision carried along the inferior aspect of the arch as far as necessary. The distal aortic segment should be trimmed appropriately to match this extended proximal incision to allow for as wide an anastomosis as possible.40 Subclavian

Flap Aortoplasty

Subclavian flap aortoplasty has become our method of choice for the repair of simple coarctation of the aorta, especially in neonates. It can be adapted to complex aortic coarctation as well, particularly when the arch is not hypoplastic proximal to the left subclavian artery. Additional mobilization of the arch vessels for more proximal vascular control is necessary. The left common carotid artery is included in the proximal cross-clamp. The

66

Progress in Pediatric Cardiology

FIGURE 2. Subclavian flap aortoplasty.

left subclavian artery is divided distally as far as necessary. An incision is made along the stenotic aorta and left subclavian artery (Figure 2A).41 The coarctation shelf is excised (Figure 2B), and the subclavian flap is trimmed appropriately (Figure 2C). The anastomosis is then performed by use of continuous 7-O polypropylene suture (Figure 2D). If the hypoplastic segment extends proximal to

the left subclavian artery, a “reversed“ subclavian artery flap aortoplasty may be necessary. Mobilization and vascular control occur even more proximally. The line of incision on the arch and left subclavian is more superior (Figure 3) .42The subclavian artery is divided, swung proximally, and trimmed to fit. The anastomosis is completed by use of a continuous 7-O polypropylene suture.

Surgery for Complex

FIGURE

Am-tic Coaftation

67

3. “Reversed” subclavian flap aortoplmty.

Patch Aortoplasty

Patch aortoplasty is used in cases in which the subclavian artery is too small for use as a flap or if the aortic defect is of sufficient length that end-to-end anastomosis is not feasible. Additionally, if significant arch obstruction is present early after coarctation repair, reoperation with patching of the affected transverse arch is favored. The aorta is

opened and the coarctation shelf excised in a manner similar to flap aortoplasty (Figure 4).43 A segment of reinforced polytetrafluoroethylene, glutaraldehyde-treated pericardium, aortic homograft, or Dacron graft is selected and cut to the length of the incision. It is trimmed at the corners and the anastomosis is created by use of a continuous 5-O or 6-O polypropylene suture.

68

Progress in Pediatric Cardiology

FIGURE

4. Patch aortoplusty.

Bypass Grafts In adolescents and adults with tubular hypoplasia or complex coarctation involving the distal ascending aorta, or transverse arch, and in others with complicated recurrence after initial repair, we have used a woven Dacron bypass graft, 18 to 20 mm in diameter, from the ascending aorta to the supraceliac abdominal aorta. The usual indications for this method are in patients with recurrent obstruction, inadequate collaterals, or those with a long hypoplastic coarctation segment with or without tubular hypoplasia. Two routes for constructing the bypass have been described: from the left subclavian artery to the descending thoracic aorta, and from the ascending aorta to the descending thoracic aorta or supraceliac abdominal aorta.44,45 We favor the second option. The proximal anastomosis is constructed between the ascending aorta and the Dacron bypass, with a partial occlusion clamp placed on the ascending aorta. The graft is then brought along the right-heart border, passed through the diaphragm, and sewn end-to-side to the supraceliac abdominal aorta. We have per-

formed this operation excellent results. Management Intracardiac

in four patients

of Coarctation Defects

and obtained

and Associated

The infant with coarctation of the aorta and an intracardiac anomaly presents challenging management problems. The most common lesion of significance is ventricular septal defect. If the defect and shunt are small by angiographic study, and the septal defect is in the perimembranous location, there is a good chance that the defect will close spontaneously after repair of the coarctation and relief of the left ventricular obstruction. Spontaneous closure is unlikely if the defect is large, multiple, or located in the apical muscular portion of the septum. For these defects, we prefer pulmonary artery banding through a left thoracotomy at the time of coarctation repair, with elective repair of the ventricular septal defect at 6 to 12 months of age.31,46 Singlestage repair through a median sternotomy is reported more commonly with repair of uncomplicated septal defects or valve anomalies, with excellent results.29*32-M,47The procedures are usually

Surgery for Complex Aortic Coarctation

performed under deep hypothermia and circulatory arrest. Standard techniques for coarctation and intracardiac repair are used. Coarctation

of the Abdominal

Aorta

Coarctation of the descending thoracic or abdominal aorta is uncommon in children. It can be approached through a left thoracotomy incision. Depending on the length of the hypoplastic segment, resection and end-to-end anastomosis or patch aortoplasty can be used. In rare cases with exceptionally long atretic segments, resection and replacement with a straight tube graft may be necessary. Postoperative

Management

Standard postoperative management principles for the care of children after cardiac surgery apply after repair of coarctation. 48Ventilatory support is continued until signs of congestive failure have resolved. Abdominal pain and hypertension are relatively common after coarctation repair, and they require close monitoring. Attention should be paid to the character of the chest tube drainage because postoperative chylothorax can be seen as a late complication. It is usually managed with tube thoracotomy drainage and low-fat alimentation with medium-chain triglycerides. In cases of significant or persistent chylous drainage, total parenteral nutrition may help decrease lymph flow and allow spontaneous closure of the leak. Occasionally, reoperation is necessary to ligate the thoracic duct.

69

TABLE 2. Operative Mortality Kirkli#

Age at operation


Primary coarctation Coarctation + VSD Coarctation + complex anomaly

year %

Kirkli#
6 6 40

Vanderbilt *

month <1 month % % 6 20 58

0 0 16

* See Table 1 for citation. five infants (23%) had an isolated coarctation with or without patent ductus arteriosus, patent foramen ovale, or bicuspid aortic valve, 41 (37%) had an associated ventricular septal defect, and 44 (40 % ) had other complex associated intracardiac anomalies. A distribution of associated lesions is shown in Table 1, Subclavian flap aortoplasty was performed in 77 infants (70%), end-to-end anastomosis was performed in 27 (25%), and a patch technique was used in 6 (5 % ). Concomitant pulmonary banding was performed in 51 infants (46%). In this group of patients, the operative mortality rate was 5.6% (Table 2). There were no operative deaths in patients with isolated coarctation or in those with only an associated ventricular septal defect. The operative mortality of those infants with complex associated cardiac defects was 16% (P < .OOl). Long-term survival is significantly lower in patients with complex associated cardiac defects (Figure 5). The extent of arch hypoplasia, the presence of associated cardiac anomalies, or the type of repair did not affect operative mortality or recurrence rates (Figure 6; P = NS).

RESULTS

Operative mortality rates for coarctation repair vary widely in reported series, from 0 to 45 % (*8-20.36.49-52) (Table 2). Several factors have been associated with higher mortality rates, including younger age at operation, tubular hypoplasia of the transverse arch, and severe associated intracardiac anomalies. We have performed coarctation repair in 110 newborns
CONCLUSION

Coarctation of the aorta often occurs with complex obstruction of the left ventricular outlfow tract or aortic arch, and with intracardiac lesions. These associated lesions often result in the development of severe congestive heart failure early in the newborn period. Prostaglandin & is very effective in increasing blood flow through the ductus arteriosus and improving distal perfusion in these sick infants, thus allowing time for appropriate preoperative evaluation. Principles of surgical management include relief of the aortic obstruction with pulmonary artery banding (if needed) or primary repair

Progress in Pediatric Cardiology

70

100 90

80 70 g

80

Y

50

30 20 10 0

I I

0

20

I

40

I

60

80

100

I 120

MONTHS FIGURE 5. Kaplan-Meier survival after correction of aortic coarctation with and without associated cardiac defects.

100 90 80 70 g Y

80 -50 --

Ii n

40 --

L

30 10 -20 --

p=rls

1_1

0

I 0

20

40

60

80

100

MONTHS FIGURE

6. Freedom from recurrence

after repair of aortic coarctation.

120

Surgery for Complex Aortic Coarctation

of an intracardiac defect. Without complex intracardiac pathology, the operative mortality rate is low, and long-term survival is excellent. Recurrence is common, but it can ofteri be managed by balloon angioplasty, although reoperation may eventually be needed.

17.

18.

REFERENCES 1. Christensen NA. Coarctation of the aorta: historical review. Mayo Clin Proc. 1948;23:322-324. 2. Paris. Retrecissement considerable de l’aorta pectorale observe a I’Hotel dieu de Paris. 1. Chir (Desault). 1791;2:107. 3. Bonnett LM. Sur la lesion dite stenose congenitale de l’aorte dans la region de l’isthme. Rev Med. 1903; 23:108, 255, 335, 418, 481. 4. Keith JD, Rowe RD, Vlad P, eds. Coarctation of the aorta. In: Heart Disease in Infancy and Childhood, 1967; New York: Macmillan; 1958:213-246. 5. Abbott ME. Coarctation of the aorta of the adult type, II. A statistical study and historical retrospect of 200 recorded cases with autopsy of stenosis or obliteration of the descending aorta in subjects over the age of two years. Am Heart J. 1928;3:574-618. 6. Reifenstein GH, Levine SA, Gross RE. Coarctation of the aorta. A review of 104 autopsied cases of the “adult” type 2 years of age or older. Am Heart 1. 1947;33:146-168. 7. Colodney NM, Carson MJ. Coarctation of the aorta in early infancy. 1 Pediatr. 1950;37:46-50. 8. Bahn RC, Edwards LE, DuShane JW. Coarctation of the aorta as a cause of death in early infancy. Pediatrics. 1952;8:192-203. 9. Blalock A, Park EA. Surgical treatment of experimental coarctation (atresia) of aorta. Ann Surg. 1944;119:445-456. 10. Gross RE, Hufnagel CA. Coarctation of the aorta. Experimental studies regarding its surgical correction. New Engl J Med. 1945;233:287-293. 11. Crafoord C, Nylin G. Congenital coarctation of the aorta and its surgical treatment. 1 Tkorac Surg. 1945; 14:347-361. 12. Gross RE. Surgical correction for coarctation of the aorta. Surgery. 1945;18:673-678. 13. Lynxwiler CP, Smith S, Babich J. Coarctation of the aorta: report of a case. Arch Pediatr. 1951:68:203205. 14. Waldhausen JA, Nahrwold DL. Repair of coarctation of the aorta with a subclavian flap. 1 Thorac Cardiovasc Surg. 1966;51:532-533. 15. Elliott RB, Starling MB, Neutze JM. Medical management of the ductus. Lancet. 1975;1:140-142. 16. Olley PM, Coceani F, Bodach E. E-type prostaglan-

19.

20.

21.

22.

23.

24.

25.

26.

27.

28.

29.

30.

71

dins: a new emergency therapy for certain cyanotic congenital heart malformations. Circulation. 1976; .53:728-731. Neutze JM, Starling MB, Elliott RB, Barrat-Boyes BG. Palliation of cyanotic congenital heart disease in infancy with E-type prostaglandins. Circulation. 1977;55:238-241. Hallman GL, Yashar JJ, Bloodwell RD, Cooley DA. Surgical correction of coarctation of the aorta in the first year of life. Ann Tkorac Surg. 1967;4:106-116. Tawes RL Jr., Aberdeen E, Waterston DJ, BonhamCarter RE. Coarctation of the aorta in infants and children: review of 333 operative cases, including 179 infants. Circulation. 1969;39(suppl I):173-184. Herrmann VM, Laks H, Fagan L, Terschluse D, William VL. Repair of aortic coarctation in the first year of life. Ann Tkorac Surg. 1978;25:57-63. Amato JJ, Rheinlander HF, Cleveland RJ. Method of enlarging the distal transverse arch in infants with hypoplasia and coarctation of the aorta. Ann Thorac Surg. 1977;23:261-263. Kirklin JW, Barrat-Boyes BG, eds. Coarctation of the aorta and interrupted arch. In: Cardiac Surgery. New York; Churchill Livingstone; 1933:1263-1325. Vouhe PR, Trinquet F, Lecompte Y, et al. Aortic coarctation with hypoplastic aortic arch. Results of extended end-to-end aortic arch anastomosis. 1 Thorac Cardiovasc Surg. 1988;96:557-563. Edwards JE. Congenital malformations of the heart and great vessels. Malformations of the thoracic aorta. In: Gould SE, ed. Pathology of the Heart and Blood Vessels, 4th ed. Springfield, IL: Charles C. Thomas; 1968:391-454. Zehr KJ, Gillinov AM, Redmond JM, et al. Repair of coarctation of the aorta in neonates and infants: a do-year experience. Ann Tkorac Surg. 1994. In press. Maron BJ, Humphries JO, Rowe RD, Mellit ED. Prognosis of surgically corrected coarctation of the aorta: a 20-year postoperative appraisal. Circulation. 1973;47:119-126. Liberthson RR, Pennington DG, Jacobs MC, Daggett WM. Coarctation of the aorta: review of 234 patients and clarification of management problems. Am 1 Cardiol. 1979;43:835-840. Park JK, Dell RB, Ellis K, Gersony WB. Surgical management of the infant with coarctation of the aorta and ventricular septal defect. 1 Am Co11 Cardiol. 1992;20:176-180. Merrill WH, Bender HW Jr. The surgical approach to congenital heart disease. Curr Probl Surg. 1985; 22:20-25. Graham TP Jr. When to operate on the child with congenital heart disease. Pediatr Clin North Am. 1984;31:1275-1291.

72

Progress in Pediatric Cardiology

31. Hammon JW Jr, Graham TP Jr, Boucek RJ Jr, et al. Operative repair of coarctation of the aorta in infancy: results with and without ventricular septal defect. Am J Cardioi. 1985;55:1555-1559. 32. Tiraboschi R, Alfieri 0, Carpentier A, Parenzan L. One stage correction of coarctation of the aorta associated with intracardiac defects in infancy. J Cardiouasc Surg. 1978;19:11-16. 33. Karl TR, Sano S, Brawn W, Mee RBB. Repair of hypoplastic or interrupted aortic arch via sternotomy. J Thorac Cardiovasc Surg. 1992;104:688-695. 34. Ungerleider RM, Ebert PA. Indications and techniques for midline approach to aortic coarctation in infants and children. Ann Thorac Surg. 1987;44: 517-522. 35. Lofland GK, Moskowitz WB, Goble M, Pieroni D, Gingell R, Wechsler AS. Hypoplastic aortic arch with severe coarctation in the neonate: repair using resection, extended aortotomy, and primary anastomosis. J Thorac Cardiouasc Surg. 1994. In press. 36. Lacour-Gayet F, Bruniaux J, Seraf A, et al. Hypoplastic transverse arch and coarctation in neonates. Surgical reconstruction of the aortic arch. A study of 66 patients. J Thorac Cardiomsc Surg. 199O;lOO: 808-816. 37. Brouwer MHJ, Cromme-Dijkhuis AH, Ebels T, Eijgelaar A. Growth of the hypoplastic aortic arch after simple coarctation resection and end-to-end anastomosis. J Thorac Cardiovasc Surg. 1992;104:426-433. 38. Myers JL, McConnell BS, Waldenhausen JA. Coarctation of the aorta in infants: does the aortic arch grow after repair? Ann Thorac Surg. 1992;54:869875. 39. Graham TP Jr, Bender HW Jr. Preoperative diagnosis and management of infants with critical congenital heart disease. Ann Thorac Surg. 1980;29:272-288. 40. Elliott MJ. Coarctation of the aorta with arch hypoplasia: improvements on a new technique. Ann Thorac Surg. 1987;44:321-323. 41. Campbell DB, Waldenhausen JA, Pierce WS, Fripp R, Whitman V. Should elective repair of coarctation of the aorta be done in infancy? J Thorac Cardiouasc

Surg. 1984;88:929-938. 42. Hart JC, Waldenhausen JA. Reversed subclavian flap angioplasty for arch coarctation of the aorta. Ann Thorac Surg. 1983;36:715-717. 43. Sade RM, Taylor AB, Chariker EL’. Aortoplasty compared with resection for coarctation of the aorta in young children. Ann Thorac Surg. 1979;28:346353. 44. Edie RN, Janani J, Attai LA, Malm JR, Robinson G. Bypass grafts for recurrent or complex coarctations of the aorta. Ann Thorac Surg. 1975;20:558-566. 45. Wada J, Kazui T. Long term results of thoracoabdominal bypass graft for atypical coarctation of the aorta. World J Surg. 1978;2:891-896. 46. Horowitz MD, Culpepper WS, Williams LC, Sundgaard-Riise K, Ochsner JL. Pulmonary artery banding: analysis of a 25-year experience. Ann Thorac Surg. 1989;48:444-450. 47. Bove EL, Minich LL, Pridjian AK, et al. The management of severe subaortic stenosis, ventricular septal defect, and aortic arch obstruction in the neonate. 1 Thorac Cardiovasc Surg. 1993;105:289-296. 48. Stewart JR, Bender HW. Management of complications of surgery for septal defects. In: Waldhausen J, Orringer M., eds. Complications in Cardiothoracic Surgery. St. Louis, MO: Mosby Year Book; 1990: 168-179. 49. Behl R, Sante P, Blesovsky A. Surgical treatment of isolated coarctation of the aorta: I8 years’ experience. Thorax. 1987;42:309-314. 50. Rostad H, Abdelnoor M, Sorland S, Tjonneland S. Coarctation of the aorta: early and late results of various surgical techniques. J Cardiovasc Surg. 1989:30:885-890. 51. Bobby JJ, Emami JM, Farmer RDT, Newman CGH. Operative survival and 40 year followup of surgical repair of aortic coarctation. BrHeartJ. 1991:65;271276. 52. Behl R, Sante P, Blesovsky A. Isolated coarctation of the aorta: surgical treatment and late results. ] Cardiovasc Surg. 1988;29:509-517.