The Japanese Journal of Surgery (1992) 22:166-170
~
SURGERYTODAY © Springer-Verlag 1992
Modified Van Praagh's Operation for Interrupted Aortic Arch with Severe Subaortic Stenosis in a Neonate KANZI MATSUI, HIROYUKIKOHNO, MANABUHISAHARA,KOJI FUKAE, MASAYOSHIUMESUE,I RYUTAROTAKAHASHIand YOHEI NISHIBAYASHI2 ~The Departments of Cardiovascular Surgeryand 2Pediatrics, Matsuyama Red Cross Hospital, Matsuyama,Japan
Abstract: A 26 day old neonate with Type B interrupted aortic arch, a ventricular septal defect and severe subaortic stenosis underwent a successful modified Van Praagh's operation, consisting of insertion of a graft between the main pulmonary artery and descending aorta, ligation of the patent ductus arteriosus and main pulmonary artery banding distal to the graft. This palliative procedure was effective and easily performed without the aid of cardiopulmonary bypass even in this severely ill neonate with such a complex defect.
septal defect leads to a substantial gradient across the outflow tract of the left ventricle. The optimal surgical management of severe LVOTO in neonates with interrupted aortic arch has not been generally agreed upon. 13-15The purpose of this paper is to describe a palliative procedure not necessitating cardiopulmonary bypass for neonates with this complex anomaly.
Key Words: interrupted aortic arch, severe subaortic stenosis, modified Van Praagh's operation
Case Report
Introduction
Interrupted aortic arch is a rare but lethal congenital malformation usually associated with complex intracardiac anomalies. 1'2 Survival depends on patency of the ductus arteriosus, 3'4 With an 80 per cent mortality during the first month of life if the defect is not corrected or palliated. 1's'6 The use of prostaglandin E1 to maintain ductal patency during the evaluation and initial treatment of these neonates has improved their condition and allowed an increasing number to undergo reparative operations, 7'8 however, the surgical results are still far from satisfactory.3'4'9-12 Moreover, when the anomaly is associated with severe obstruction of the left ventricular outflow tract (LVOTO), the surgical management becomes more difficult, firstly, because the usual palliation with arch reconstruction and pulmonary artery banding results in biventricular obstruction and, secondly, because the primary repair with arch reconstruction and closure of the ventricular Reprint requests to: Kanzi Matsui, MD, The Department of Cardiovascular Surgery, Matsuyama Red Cross Hospital, Bunkyo-cho 1, Matsuyama 790, Japan (Received for publication on Sep. 4, 1990)
A 20 day old male infant weighing 3,970 g was referred to our emergency department on ,July 5, 1989, for severe dyspnea. Physical examination revealed a pale and cyanotic infant whose brachial and femoral pulses were absent. The liver was palpable 6 cm below the right costal margin and a chest X-ray film showed marked pulmonary vascular congestion and cardiomegaly with a cardiothoracic ratio of 62 per cent. Two-dimensional echocardiograms revealed Type B interruption of the aortic arch distal to the left common carotid artery, a large ventricular septal defect and an enlarged left ventricle with severely reduced wall motion. Severe subaortic stenosis and hypoplastic aortic anulus were also disclosed (Fig. 1). Mechanical ventilation and emergency medical therapy including the continuous infusion of prostaglandin E1 and dopamine were instituted, after which the peripheral pulses became palpable and the baby's condition improved. Cardiac catheterization and angiocardiographic examinations were performed three days after admission, the results of which confirmed Type B interrupted aortic arch and an aberrant origin of the right subclavian artery from the descending aorta. A left ventriculogram revealed severe subvalvular and valvular aortic stenosis (Fig. 2). The ratios of the diameters at the sites of the subvalvular and valvular aortic stenosis to the descending aortic diameter at the level of the diaphragm of the lateral angiographic pro-
K. Matsui et al.: Van Praagh's Operation for IAA with Severe AS
167
Fig. 1. Echocardiograms. Left: interruption of the aortic arch proximal to the left subclavian artery (LSA) shown from the suprasternal view. Right: severe subaortic stenosis shown from the long axis view. AAO, ascending aorta; DAO, descending aorta; RV, right ventricle; LV, left ventricle; LA, left atrium; AO, aorta
Fig. 2. Left ventriculogram of lateral projection. Subaortic stenosis, shown by the arrow, and hypoplasia of the aortic anulus can be seen. MPA, main pulmonary artery; LPA, left pulmonary artery; VSD, ventricular septal defect; other abbreviations, see Fig. 1
jection were 0.5 and 0.6, respectively. The pressure gradient across the left ventricular outflow tract was not measured because the ascending aorta could not be entered. The baby underwent surgery at 26 days of age. Considering the severe L V O T O , a palliative operation constructing a new route of systemic circulation from the main pulmonary artery to the descending aorta was performed. Through a left lateral thoracotomy in the fourth intercostal space, the Pericardium was opened posterior to the phrenic nerve and the main pulmonary artery encircled. A 7 m m knitted Dacron (Golaski) tube graft was placed between the main pulmonary artery and descending aorta. The graft was first anastomosed end-to-side to the descending aorta with a running 6 - 0 monofilament suture, after which it was looped over the hilum of the left lung. With the proximal portion of the main pulmonary artery controlled by a partial occlusion clamp, the other end of the graft was slightly beveled and anastomosed to the side of the main pulmonary artery. With the graft open, the patent ductus arteriosus was doubly ligated. The main pulmonary artery was then banded distal to the graft using a 3 m m polytetrafluoroethylene (PTFE)
graft as a band, which was tightened until the systolic pressure distal to it became 35mmHg. The final anatomic arrangement is illustrated in Fig. 3. The baby's postoperative course was uneventful and the endotracheal tube removed on the eighth postoperative day. Repeat catheterization five weeks following the opperation demonstrated effective pulmonary artery banding and a mild pressure gradient between the main pulmonary artery and descending
Table 1. Pre- and postoperative cardiac catheterization data. Pressure (mmHg) Site Preop. Postop. RA RV MPA LPA LA LV DAO
a = 12, v = 9 ( 9 ) 71/0, EDP = 11 67/38 (48) 50/26 (30) a=21, v=23(16) 81/2, EDP = 14 54/36 (46)
a=5, v=2(1) 98/-10, EDP = 5 92/28 (48) 37/22 (28) a=8, v=7(2) 74/28 (45)
Abbreviations: RA, right atrium; EDP, end diastolic pressure; others, see Fig. 1 and Fig. 2. Mean values are indicated by parentheses.
168
K. Matsui et al.: Van Praagh's Operation for IAA with Severe AS 14 months following the operation, he is active and growing well with a weight of 8.0 kg.
Discussion
Fig. 3. Schema at the end of the surgical procedure. RSA, aberrant right subclavian artery; RPA, right pulmonary artery; other abbreviations, see Figs 1 and 2
aorta (Table 1). The blood oxygen saturation of the descending aorta on room air respiration was 71 per cent. Angiograms showed smooth blood flow from the main pulmonary artery to the descending aorta, but that the right pulmonary artery was completely occluded at its takeoff due to impingement by the band (Fig. 4). However, because the infant's condition remained stable despite this, repositioning of the pulmonary artery band was not attempted and he was discharged seven weeks after the operation. Now,
Subaortic stenosis of varying degree is common in patients with interrupted aortic arch and a ventricular septal defect. It is primarily caused by posterior displacement of the conal septum into the left ventricle. 6'~6 The other anatomic causes of LVOTO include hypertrophy of the anterolateral muscle bundle of the left ventricle, 17 a narrow aortic valve anulus and ascending aorta, and a bicuspid, dysplastic aortic valve. 12 The severity of LVOTO is difficult to assess preoperatively because the large ventricular septal defect decompresses the left ventricle and minimizes the pressure gradient across the obstructed outflow tract. However, the preoperative assessment of LVOTO is crucial because the obstruction becomes critical following either a palliative or corrective procedure when the ascending aorta is expected to carry the total systemic cardiac output. Recently, Ilbawi and associates 15 reported that the ratio of the left ventricular outflow tract diameter to the descending aortic diameter, as assessed by angiograms, is helpful in the preoperative assessment of hemodynamically significant LVOTO in patients with interrupted aortic arch. They suggested ratios of 0.6 or less to indicate that the left ventricular out-flow tract is too small to handle the total systemic circulation. In fact, according to their report, of ten patients with ratios of 0.6 or less, all four patients who underwent reconstruction of the aortic arch and pulmonary artery banding died as a result of low cardiac output soon after the operation. In contrast, the other six patients, who underwent pulmonary artery banding and insertion of a graft between the main pulmonary artery and descending aorta, made an uneventful recovery. Our patient, who had a significantly reduced ratio of 0.5 at the subvalvular region,
Fig. 4. Postoperative main pulmonary artery angiogram (left; postero-anterior projection) and graft angiogram (right; left anterior oblique projection). Smooth blood flow through the graft, shown by the arrow, and complete occlusion of the right pulmonary artery can be seen
169
K. Matsui et al.: Van Praagh's Operation for [AA with Severe AS also had an uneventful recovery following the same palliative procedure. Although some recent reports 4'm-t2'~8 state a preference for primary total repair to a staged operation for interrupted aortic arch with a simple ventricular septal defect, the optimal surgical m a n a g e m e n t of interrupted aortic arch complex is still controversial. 9'~9 Moreover, the presence of L V O T O in particular necessitates modification of the present surgical approach to this complex lesion. Ideally, complete correction of the lesion with reconstruction of the aortic arch, closure of the ventricular septal defect and resection of the obstructing muscle would be the procedure of choice, however, this cannot be p e r f o r m e d in neonates with severe L V O T O where the ascending aorta and aortic anulus are small. Other alternatives such as insertion of a left ventricle-descending aorta apical conduit ~3 to bypass the L V O T O or patch enlargement of the left ventricular outflow tract with Konno's procedure 2° to relieve the obstruction have serious disadvantages, mainly due to the necessity of using a small conduit or the lack of a small prosthetic valve for neonates and small infants. Recently, Yasui and associates 14 reported an ingenious new approach for primary repair in which a tunnel patch closure of the ventricular septal defect and anastomosis of the proximal main pulmonary artery to the ascending aorta are performed to redirect the left ventricular blood flow to the ascending aorta through the ventricular septal defect and right ventricular outflow tract. This is an excellent method for dealing with the subvalvular and valvular aortic stenosis but it fails to bypass the small ascending aorta. The other drawback of this approach is its use of a small valved conduit to reconstruct the right ventricular outflow tract in neonates. The palliative procedure reported herein is the same operation as that originally reported by Van Praagh and associates 6 for interrupted aortic arch in 1971 and modified by Litwin and associates 2~ in 1972. When this procedure is applied to patients with interrupted aortic arch and severe L V O T O , it has several advantages. Firstly, it provides an alternative route for the systemic circulation through the ventricular septal defect and pulmonary artery. Secondly, it can be performed easily even in sick small neonates without the aid of cardiopulmonary bypass. Thirdly, it allows for survival until the patient grows to an age when total repair using a tunnel patch closure of the ventricular septal defect is or an apical conduit 13 can be safely performed. Although this palliative procedure is relatively simple, it does necessitate precise technique and care must be taken to place the graft and band properly to avoid any drawbacks. One potential drawback of this procedure is impingement of the pulmonary artery
band on the takeoff of the right pulmonary artery.IS In our patient, the right pulmonary artery was completely occluded by the band and we regret that we did not use a much narrower tape than the bulky 3 m m P T F E graft as the band. A n o t h e r drawback is the difficulty in assessing the appropriate extent of banding because of the biphasic, that is, systolic and diastolic, pulmonary blood flow which may lead to postoperative pulmonary congestion and persistent heart failure. To avoid this complication, tighter banding than usual should be performed. On the other hand, the band may create or aggravate subpulmonary or subaortic stenosis mainly due to progressive hypertrophy of the conal septum. 6'16'22 Therefore, close follow-up after the operation is mandatory for appropriate timing of the subsequent intracardiac repair. This palliative procedure is theoretically effective for such other lesions as hypoplastic left heart syndrome or single ventricle with severe unresectable subaortic or aortic stenosis. Moreover, its successful application for hypoplastic left heart syndrome was also recently reported. 23
References 1. Moller JH, Edwards JE (1965) Interruption of aortic arch: anatomic patterns and associated cardiac malformations. AJR 95:557-572 2. Roberts WC, Morrow AG, Braunwald E (1962) Complete interruption of the aortic arch. Circulation 26:39-59 3. Moulton AL, Bowman FO (1981) Primary definitive repair of type B interrupted aortic arch, ventricular septal defect, and patent ductus arteriosus. Early and late results. J Thorac Cardiovasc Surg 82:501-510 4. Norwood WI, Lang P, Castaneda AR, Hougen TJ (1983) Reparative operations for interrupted aortic arch with ventricular septal defect. J Thorac Cardiovasc Surg 86:832-837 5. Rochette M, Stanley P, Ethier MF, Davignon A (1968) Complete interruption of the aortic arch in infancy. Can Med Ass J 98:131-139 6. Van Praagh R, Bernhard WF, Rosenthal A, Parisi LF, Fyler DC (1971) Interrupted aortic arch: surgical treatment. Am J Cardiol 27:200-211 7. Lang P, Freed MD, Rosenthal A, Castaneda AR, Nadas AS (1977) The use of prostaglandin E1 in an infant with interruption of the aortic arch. J Pediatr 91:805-807 8. Heymann MA, Berman W Jr, Rudolph AM, Whitman V (i-979) Dilatation of the ductus arteriosus by prostaglandin E 1 in aortic arch abnormalities. Circulation 59:169-173. 9. Braunlin EA, Lock JE, Foker JE (1983) Repair of type B interruption of the aortic arch. Results and follow-up. J Thorac Cardiovasc Surg 86:920-925 10. Hammon JW Jr, Merrill WH, Prager RL, Graham TP Jr, Bender HW Jr (1986) Repair of interrupted aortic arch and associated malformations in infancy: indications for complete or partial repair. Ann Thorac Surg 42:17-21 11. Scott WA, Rocchini AP, Bove EL, Behrendt DM, Beekman RH, Dick M, Serwer G, Snider R, Rosenthal A (1988) Repair of interrupted aortic arch in infancy. J Thorac Cardiovasc Surg 96:564-568
170 12. Sell JE, Jonas RA, Mayer JE, Blackstone EH, Kirklin JW, Castaneda AR (1988) The results of a surgical program for interrupted aortic arch. J Thorac Cardiovasc Surg 96:864877 13. Norwood WI, Lang P, Castaneda AR, Murphy JD (1983) Management of infants with left ventricular outflow obstruction by conduit interposition between the ventricular apex and thoracic aorta. J Thorac Cardiovasc Surg 86:771-776 14. Yasui H, Kado H, Nakano E, Yonenaga K, Mitani A, Tomita Y, Iwao H, Yoshii K, Mizoguchi Y, Sunagawa H (1987) Primary repair of interrupted aortic arch and severe aortic stenosis in neonates. J Thorac Cardiovasc Surg 93:539-545 15. Ilbawi MN, Idriss FS, DeLeon SY, Muster AJ, Benson DW Jr, Paul MH (1988) Surgical management of patients with interrupted aortic arch and severe subaortic stenosis. Ann Thorac Surg 45:174-180 16. Becu LM, Tauxe WN, DuShane JW, Edwards JE (1955) A complex of congenital cardiac anomalies: ventricular septal defect, biventricular origin of the pulmonary trunk, and subaortic stenosis. Am Heart J 50:901-911 17. Moulaert AJ, Oppenheimer-Dekker A (1976) Anterolateral
K. Matsui et al.: Van Praagh's Operation for I A A with Severe AS
18.
19.
20.
21.
22.
23.
muscle bundle of the left ventricle, bulvoventricular flange and subaortic stenosis. Am J Cardiol 37:78-81 Monro JL, Bunton RW, Sutherland GR, Keeton BR (1989) Correction of interrupted aortic arch. J Thorac Cardiovasc Surg 98:421-427 Kron IL, Rheuban KS, Carpenter MS, Nolan SP (1983) Interrupted aortic arch. A conservative approach for the sick neonate. J Thorac Cardivasc Surg 86:37-40 Konno S, Imai Y, Iida Y, Nakajima M, Tatsuno K (1975) A new method for prosthetic valve replacement in congenital aortic stenosis associated with hypoplasia of the aortic valve ring. J Thorac Cardiovasc Surg 70:909-917 Litwin SB, Van Praagh R, Bernhard WF (1972) A palliative operation for certain infants with aortic arch interruption. Ann Thorac Surg 14:369-375 Freedom RM, Bain HH, Esplugas E, Dische R, Rowe RD (1977) Ventricular septal defect in interruption of aortic arch. Am J Cardiol 39:572-582 Tucker WY, McKone RC, Weesner KM, Kon ND (1990) Hypoplastic left heart syndrome: palliation without cardiopulmonary bypass. J Thorac Cardiovasc Surg 99:885-888
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SURGERYTODAY © Springer-Verlag 1992
Modified Van Praagh's Operation for Interrupted Aortic Arch with Severe Subaortic Stenosis in a Neonate KANZI MATSUI, HIROYUKIKOHNO, MANABUHISAHARA,KOJI FUKAE, MASAYOSHIUMESUE,I RYUTAROTAKAHASHIand YOHEI NISHIBAYASHI2 ~The Departments of Cardiovascular Surgeryand 2Pediatrics, Matsuyama Red Cross Hospital, Matsuyama,Japan
Abstract: A 26 day old neonate with Type B interrupted aortic arch, a ventricular septal defect and severe subaortic stenosis underwent a successful modified Van Praagh's operation, consisting of insertion of a graft between the main pulmonary artery and descending aorta, ligation of the patent ductus arteriosus and main pulmonary artery banding distal to the graft. This palliative procedure was effective and easily performed without the aid of cardiopulmonary bypass even in this severely ill neonate with such a complex defect.
septal defect leads to a substantial gradient across the outflow tract of the left ventricle. The optimal surgical management of severe LVOTO in neonates with interrupted aortic arch has not been generally agreed upon. 13-15The purpose of this paper is to describe a palliative procedure not necessitating cardiopulmonary bypass for neonates with this complex anomaly.
Key Words: interrupted aortic arch, severe subaortic stenosis, modified Van Praagh's operation
Case Report
Introduction
Interrupted aortic arch is a rare but lethal congenital malformation usually associated with complex intracardiac anomalies. 1'2 Survival depends on patency of the ductus arteriosus, 3'4 With an 80 per cent mortality during the first month of life if the defect is not corrected or palliated. 1's'6 The use of prostaglandin E1 to maintain ductal patency during the evaluation and initial treatment of these neonates has improved their condition and allowed an increasing number to undergo reparative operations, 7'8 however, the surgical results are still far from satisfactory.3'4'9-12 Moreover, when the anomaly is associated with severe obstruction of the left ventricular outflow tract (LVOTO), the surgical management becomes more difficult, firstly, because the usual palliation with arch reconstruction and pulmonary artery banding results in biventricular obstruction and, secondly, because the primary repair with arch reconstruction and closure of the ventricular Reprint requests to: Kanzi Matsui, MD, The Department of Cardiovascular Surgery, Matsuyama Red Cross Hospital, Bunkyo-cho 1, Matsuyama 790, Japan (Received for publication on Sep. 4, 1990)
A 20 day old male infant weighing 3,970 g was referred to our emergency department on ,July 5, 1989, for severe dyspnea. Physical examination revealed a pale and cyanotic infant whose brachial and femoral pulses were absent. The liver was palpable 6 cm below the right costal margin and a chest X-ray film showed marked pulmonary vascular congestion and cardiomegaly with a cardiothoracic ratio of 62 per cent. Two-dimensional echocardiograms revealed Type B interruption of the aortic arch distal to the left common carotid artery, a large ventricular septal defect and an enlarged left ventricle with severely reduced wall motion. Severe subaortic stenosis and hypoplastic aortic anulus were also disclosed (Fig. 1). Mechanical ventilation and emergency medical therapy including the continuous infusion of prostaglandin E1 and dopamine were instituted, after which the peripheral pulses became palpable and the baby's condition improved. Cardiac catheterization and angiocardiographic examinations were performed three days after admission, the results of which confirmed Type B interrupted aortic arch and an aberrant origin of the right subclavian artery from the descending aorta. A left ventriculogram revealed severe subvalvular and valvular aortic stenosis (Fig. 2). The ratios of the diameters at the sites of the subvalvular and valvular aortic stenosis to the descending aortic diameter at the level of the diaphragm of the lateral angiographic pro-
K. Matsui et al.: Van Praagh's Operation for IAA with Severe AS
167
Fig. 1. Echocardiograms. Left: interruption of the aortic arch proximal to the left subclavian artery (LSA) shown from the suprasternal view. Right: severe subaortic stenosis shown from the long axis view. AAO, ascending aorta; DAO, descending aorta; RV, right ventricle; LV, left ventricle; LA, left atrium; AO, aorta
Fig. 2. Left ventriculogram of lateral projection. Subaortic stenosis, shown by the arrow, and hypoplasia of the aortic anulus can be seen. MPA, main pulmonary artery; LPA, left pulmonary artery; VSD, ventricular septal defect; other abbreviations, see Fig. 1
jection were 0.5 and 0.6, respectively. The pressure gradient across the left ventricular outflow tract was not measured because the ascending aorta could not be entered. The baby underwent surgery at 26 days of age. Considering the severe L V O T O , a palliative operation constructing a new route of systemic circulation from the main pulmonary artery to the descending aorta was performed. Through a left lateral thoracotomy in the fourth intercostal space, the Pericardium was opened posterior to the phrenic nerve and the main pulmonary artery encircled. A 7 m m knitted Dacron (Golaski) tube graft was placed between the main pulmonary artery and descending aorta. The graft was first anastomosed end-to-side to the descending aorta with a running 6 - 0 monofilament suture, after which it was looped over the hilum of the left lung. With the proximal portion of the main pulmonary artery controlled by a partial occlusion clamp, the other end of the graft was slightly beveled and anastomosed to the side of the main pulmonary artery. With the graft open, the patent ductus arteriosus was doubly ligated. The main pulmonary artery was then banded distal to the graft using a 3 m m polytetrafluoroethylene (PTFE)
graft as a band, which was tightened until the systolic pressure distal to it became 35mmHg. The final anatomic arrangement is illustrated in Fig. 3. The baby's postoperative course was uneventful and the endotracheal tube removed on the eighth postoperative day. Repeat catheterization five weeks following the opperation demonstrated effective pulmonary artery banding and a mild pressure gradient between the main pulmonary artery and descending
Table 1. Pre- and postoperative cardiac catheterization data. Pressure (mmHg) Site Preop. Postop. RA RV MPA LPA LA LV DAO
a = 12, v = 9 ( 9 ) 71/0, EDP = 11 67/38 (48) 50/26 (30) a=21, v=23(16) 81/2, EDP = 14 54/36 (46)
a=5, v=2(1) 98/-10, EDP = 5 92/28 (48) 37/22 (28) a=8, v=7(2) 74/28 (45)
Abbreviations: RA, right atrium; EDP, end diastolic pressure; others, see Fig. 1 and Fig. 2. Mean values are indicated by parentheses.
168
K. Matsui et al.: Van Praagh's Operation for IAA with Severe AS 14 months following the operation, he is active and growing well with a weight of 8.0 kg.
Discussion
Fig. 3. Schema at the end of the surgical procedure. RSA, aberrant right subclavian artery; RPA, right pulmonary artery; other abbreviations, see Figs 1 and 2
aorta (Table 1). The blood oxygen saturation of the descending aorta on room air respiration was 71 per cent. Angiograms showed smooth blood flow from the main pulmonary artery to the descending aorta, but that the right pulmonary artery was completely occluded at its takeoff due to impingement by the band (Fig. 4). However, because the infant's condition remained stable despite this, repositioning of the pulmonary artery band was not attempted and he was discharged seven weeks after the operation. Now,
Subaortic stenosis of varying degree is common in patients with interrupted aortic arch and a ventricular septal defect. It is primarily caused by posterior displacement of the conal septum into the left ventricle. 6'~6 The other anatomic causes of LVOTO include hypertrophy of the anterolateral muscle bundle of the left ventricle, 17 a narrow aortic valve anulus and ascending aorta, and a bicuspid, dysplastic aortic valve. 12 The severity of LVOTO is difficult to assess preoperatively because the large ventricular septal defect decompresses the left ventricle and minimizes the pressure gradient across the obstructed outflow tract. However, the preoperative assessment of LVOTO is crucial because the obstruction becomes critical following either a palliative or corrective procedure when the ascending aorta is expected to carry the total systemic cardiac output. Recently, Ilbawi and associates 15 reported that the ratio of the left ventricular outflow tract diameter to the descending aortic diameter, as assessed by angiograms, is helpful in the preoperative assessment of hemodynamically significant LVOTO in patients with interrupted aortic arch. They suggested ratios of 0.6 or less to indicate that the left ventricular out-flow tract is too small to handle the total systemic circulation. In fact, according to their report, of ten patients with ratios of 0.6 or less, all four patients who underwent reconstruction of the aortic arch and pulmonary artery banding died as a result of low cardiac output soon after the operation. In contrast, the other six patients, who underwent pulmonary artery banding and insertion of a graft between the main pulmonary artery and descending aorta, made an uneventful recovery. Our patient, who had a significantly reduced ratio of 0.5 at the subvalvular region,
Fig. 4. Postoperative main pulmonary artery angiogram (left; postero-anterior projection) and graft angiogram (right; left anterior oblique projection). Smooth blood flow through the graft, shown by the arrow, and complete occlusion of the right pulmonary artery can be seen
169
K. Matsui et al.: Van Praagh's Operation for [AA with Severe AS also had an uneventful recovery following the same palliative procedure. Although some recent reports 4'm-t2'~8 state a preference for primary total repair to a staged operation for interrupted aortic arch with a simple ventricular septal defect, the optimal surgical m a n a g e m e n t of interrupted aortic arch complex is still controversial. 9'~9 Moreover, the presence of L V O T O in particular necessitates modification of the present surgical approach to this complex lesion. Ideally, complete correction of the lesion with reconstruction of the aortic arch, closure of the ventricular septal defect and resection of the obstructing muscle would be the procedure of choice, however, this cannot be p e r f o r m e d in neonates with severe L V O T O where the ascending aorta and aortic anulus are small. Other alternatives such as insertion of a left ventricle-descending aorta apical conduit ~3 to bypass the L V O T O or patch enlargement of the left ventricular outflow tract with Konno's procedure 2° to relieve the obstruction have serious disadvantages, mainly due to the necessity of using a small conduit or the lack of a small prosthetic valve for neonates and small infants. Recently, Yasui and associates 14 reported an ingenious new approach for primary repair in which a tunnel patch closure of the ventricular septal defect and anastomosis of the proximal main pulmonary artery to the ascending aorta are performed to redirect the left ventricular blood flow to the ascending aorta through the ventricular septal defect and right ventricular outflow tract. This is an excellent method for dealing with the subvalvular and valvular aortic stenosis but it fails to bypass the small ascending aorta. The other drawback of this approach is its use of a small valved conduit to reconstruct the right ventricular outflow tract in neonates. The palliative procedure reported herein is the same operation as that originally reported by Van Praagh and associates 6 for interrupted aortic arch in 1971 and modified by Litwin and associates 2~ in 1972. When this procedure is applied to patients with interrupted aortic arch and severe L V O T O , it has several advantages. Firstly, it provides an alternative route for the systemic circulation through the ventricular septal defect and pulmonary artery. Secondly, it can be performed easily even in sick small neonates without the aid of cardiopulmonary bypass. Thirdly, it allows for survival until the patient grows to an age when total repair using a tunnel patch closure of the ventricular septal defect is or an apical conduit 13 can be safely performed. Although this palliative procedure is relatively simple, it does necessitate precise technique and care must be taken to place the graft and band properly to avoid any drawbacks. One potential drawback of this procedure is impingement of the pulmonary artery
band on the takeoff of the right pulmonary artery.IS In our patient, the right pulmonary artery was completely occluded by the band and we regret that we did not use a much narrower tape than the bulky 3 m m P T F E graft as the band. A n o t h e r drawback is the difficulty in assessing the appropriate extent of banding because of the biphasic, that is, systolic and diastolic, pulmonary blood flow which may lead to postoperative pulmonary congestion and persistent heart failure. To avoid this complication, tighter banding than usual should be performed. On the other hand, the band may create or aggravate subpulmonary or subaortic stenosis mainly due to progressive hypertrophy of the conal septum. 6'16'22 Therefore, close follow-up after the operation is mandatory for appropriate timing of the subsequent intracardiac repair. This palliative procedure is theoretically effective for such other lesions as hypoplastic left heart syndrome or single ventricle with severe unresectable subaortic or aortic stenosis. Moreover, its successful application for hypoplastic left heart syndrome was also recently reported. 23
References 1. Moller JH, Edwards JE (1965) Interruption of aortic arch: anatomic patterns and associated cardiac malformations. AJR 95:557-572 2. Roberts WC, Morrow AG, Braunwald E (1962) Complete interruption of the aortic arch. Circulation 26:39-59 3. Moulton AL, Bowman FO (1981) Primary definitive repair of type B interrupted aortic arch, ventricular septal defect, and patent ductus arteriosus. Early and late results. J Thorac Cardiovasc Surg 82:501-510 4. Norwood WI, Lang P, Castaneda AR, Hougen TJ (1983) Reparative operations for interrupted aortic arch with ventricular septal defect. J Thorac Cardiovasc Surg 86:832-837 5. Rochette M, Stanley P, Ethier MF, Davignon A (1968) Complete interruption of the aortic arch in infancy. Can Med Ass J 98:131-139 6. Van Praagh R, Bernhard WF, Rosenthal A, Parisi LF, Fyler DC (1971) Interrupted aortic arch: surgical treatment. Am J Cardiol 27:200-211 7. Lang P, Freed MD, Rosenthal A, Castaneda AR, Nadas AS (1977) The use of prostaglandin E1 in an infant with interruption of the aortic arch. J Pediatr 91:805-807 8. Heymann MA, Berman W Jr, Rudolph AM, Whitman V (i-979) Dilatation of the ductus arteriosus by prostaglandin E 1 in aortic arch abnormalities. Circulation 59:169-173. 9. Braunlin EA, Lock JE, Foker JE (1983) Repair of type B interruption of the aortic arch. Results and follow-up. J Thorac Cardiovasc Surg 86:920-925 10. Hammon JW Jr, Merrill WH, Prager RL, Graham TP Jr, Bender HW Jr (1986) Repair of interrupted aortic arch and associated malformations in infancy: indications for complete or partial repair. Ann Thorac Surg 42:17-21 11. Scott WA, Rocchini AP, Bove EL, Behrendt DM, Beekman RH, Dick M, Serwer G, Snider R, Rosenthal A (1988) Repair of interrupted aortic arch in infancy. J Thorac Cardiovasc Surg 96:564-568
170 12. Sell JE, Jonas RA, Mayer JE, Blackstone EH, Kirklin JW, Castaneda AR (1988) The results of a surgical program for interrupted aortic arch. J Thorac Cardiovasc Surg 96:864877 13. Norwood WI, Lang P, Castaneda AR, Murphy JD (1983) Management of infants with left ventricular outflow obstruction by conduit interposition between the ventricular apex and thoracic aorta. J Thorac Cardiovasc Surg 86:771-776 14. Yasui H, Kado H, Nakano E, Yonenaga K, Mitani A, Tomita Y, Iwao H, Yoshii K, Mizoguchi Y, Sunagawa H (1987) Primary repair of interrupted aortic arch and severe aortic stenosis in neonates. J Thorac Cardiovasc Surg 93:539-545 15. Ilbawi MN, Idriss FS, DeLeon SY, Muster AJ, Benson DW Jr, Paul MH (1988) Surgical management of patients with interrupted aortic arch and severe subaortic stenosis. Ann Thorac Surg 45:174-180 16. Becu LM, Tauxe WN, DuShane JW, Edwards JE (1955) A complex of congenital cardiac anomalies: ventricular septal defect, biventricular origin of the pulmonary trunk, and subaortic stenosis. Am Heart J 50:901-911 17. Moulaert AJ, Oppenheimer-Dekker A (1976) Anterolateral
K. Matsui et al.: Van Praagh's Operation for I A A with Severe AS
18.
19.
20.
21.
22.
23.
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