Pediatr Cardiol 11:117-119, 1990
Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1990
Truncus Arteriosus with Type B Interrupted Aortic Arch: Correction in the N e o n a t e P.J. Raudkivi, G.R. Sutherland, J.C. Edwards, J.M. Manners, B.R. Keeton, and J.L. Monro Wessex Cardiothoracic Centre, The General Hospital, Southampton, UK
SUMMARY. Two neonates with truncus arteriosus (TA) and type B interrupted aortic arch are reported. In both, a homograft was used to connect the right ventricle to the pulmonary artery, while the arch continuity was established by direct anastomosis of the aortic arch to the descending aorta. KEY WORDS: Truncus arteriosus - - Interrupted aortic arch - - Homograft r e p a i r pothermic extracorporeal circulation - - Neonate
Interruption of the aortic arch occurs in about 14% of patients with truncus arteriosus (TA) [1]. The first successful repair of this lesion was reported in 1971 by Gomes and McGoon [3]: they used the ductus arteriosus to maintain continuity between the truncus and the descending aorta. Their experience with a total of seven cases with three deaths has since been updated [2]. One of these patients was less than 6 months of age. We report herein the successful outcome of surgery in two neonates with TA and type B interrupted aortic arch. A homograft was used for the right ventricle to pulmonary artery connection, and aortic continuity was provided by direct anastomosis of the arch to the descending aorta.
Hy-
stopped, the aorta cross-clamped, and St. Thomas's cardioplegic solution (20 ml/kg) injected into the aortic root. The right atrial cannula was removed and the foramen ovale closed. The descending aorta and head vessels were occluded, the pulmonary arteries detached from the truncus and the resulting truncal defect closed with a patch of dura mater. The duct was divided and all duct tissue removed from the descending aorta which was then anastomosed to the aortic arch at the base of the left carotid artery. After great care had been taken to remove air from the aortic arch, the venous cannula was reinserted and bypass recommended. After a further period of bypass, the circulation was again arrested (Table 1). The ventricular septal defect was closed with a dacron patch through a high right ventriculotomy, and continuity established between the right ventricle and pulmonary arteries with an antibiotically sterilized aortic homograft. The proximal anastomosis was finally completed during bypass as the patient was being rewarmed. Bypass was then discontinued, the cannulae removed, and the chest closed.
Methods Anesthesia was established in routine fashion [4] and the patients' nasopharyngeal temperature reduced to 28~ by surface cooling. The chest was opened by median sternotomy. Extensive dissection of the aorta, head vessels, and pulmonary arteries was performed and a single aortic and single right atrial cannula inserted. A Dideco membrane oxygenator was primed with 2 U blood, with appropriate doses of sodium bicarbonate and glucose. Maximum flow rates were 100 ml/kg/min. A short period of bypass was used to lower the temperature to 15~ during which the duct and pulmonary arteries were occluded. Bypass was
Address offprint requests to: Mr. J.L. Monro, Consultant Cardiac Surgeon, Wessex Cardiothoracic Centre, The General Hospital, Southampton, S09 4XY, UK.
Case 1 A female baby was born at 38 weeks' gestation, weighing 2.7 kg. She was noted to be tachypnoeic soon after birth and a diagnosis of TA was made. Mild truncal valve regurgitation was noted. Despite treatment with digoxin and diuretics, she remained in moderate congestive cardiac failure. However, by day 25 of life her condition deteriorated with increasing congestive cardiac failure. Two days later she required ventilation, and repeat echocardiography demonstrated a type B interrupted arch in addition to the type I TA. On the following day (March 25, 1987), she was taken to the operating room without prior cardiac catheterization, weighing 2.4 kg. Correction was carried out as described above. The smallest available antibiotically sterilized homograft was 23-mm internal diameter, and this was narrowed to a 14-mm
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Pediatric Cardiology Vol. 11, No. 2, 1990
Table 1. Clinical and bypass data of two neonatal cases of truncus arteriosus (TA) with type B interrupted aortic arch
Age Weight Diagnosis
Temperature of arrest Duration of first arrest Duration of second arrest Total bypass time
Case 1
Case 2
28 days 2.4 kg Type I TA, mild truncal valve regurgitation Type B interrupted aortic arch, anomalous right subclavian artery from descending aorta 16~ 31 21 123 min
14 days 2.2 kg Type II TA Type B interrupted aortic arch
internal diameter bicuspid valve by removing the right coronary cusp and appropriate aortic wall. Four hours postoperatively, she suddenly became severely hypotensive and required a short period of external cardiac massage, responding to inotropic support. She was electively ventilated for 3 days and returned to the ward 9 days postoperatively, being discharged on postoperative day 16. She remains well and was restudied 8 months postoperatively. There was a 20 mmHg gradient across the aortic arch with a satisfactory repair (Fig. 1) but narrowing of the proximal right pulmonary artery (Fig. 2). The ventricular septal defect was securely closed.
Case 2 A female baby, born at 38 weeks gestation and weighing 2.4 kg, was noted to have a harsh systolic murmur. A diagnosis of TA was made by echocardiography, and she was started on digoxin and diuretics. She was transferred to this hospital on day 5 of life but remained in cardiac failure. Repeat echocardiography confirmed a type II TA and suggested the possibility of a type B interrupted aortic arch. By day 14 of life the patient was in severe cardiac failure and her weight had dropped to 2.2 kg. Cardiac catheterization was performed because we could not be absolutely certain about the interrupted arch by echocardiography alone. This confirmed a type II TA with virtually no truncal regurgitation and a type B interrupted aortic arch. Correction was carried out on the same day (December 9, 1987) in the manner described above, using a 13-mm internal diameter antibiotically sterilized aortic homograft. Postoperatively, her course was stormy with two periods of cardiac arrest which responded to resuscitation. It is possible that a rise in pulmonary vascular resistance contributed to the arrests, despite the accepted steps taken to diminish this complication. (These steps included high oxygenation, low normal carbon dioxide tension, prompt correction of metabolic acidosis, and adequate analgesia by infusion. The vasodilator and inotrope of choice were trinitroglycerine and dobutamine.) She required ventilation for 11 days postoperatively but steadily made progress and was returned to the ward on postoperative day 13. Postoperative echocardiography with color Doppler showed an
16~ 54 42 98 min
intact ventricular septal defect patch, and no significant gradient from left ventricle to descending aorta. There was a gradient of 40 mmHg across the origin of the right pulmonary artery. She was discharged from this hospital on postoperative day 26.
Discussion Since 1974 we have corrected 16 infants with TA with three deaths. Seven of them were neonates (two deaths). We have also operated on 10 infants with type B interrupted aortic arch, with one death: seven were neonates, one of w h o m died. The successful o u t c o m e in these two small, desperately ill neonates with both TA and interrupted aortic arch reflects this combined experience which includes the use of homograft conduits. We were fortunate to have a small homograft for case 2, but the technique of narrowing a homograft, as used in case 1, is most helpful and has been used in two of the other neonates undergoing repair of TA. The fact that both patients have some residual narrowing of the right pulmonary artery illustrates the considerable difficulty encountered in these very small infants in establishing a communication with the pulmonary arteries. This is particularly so in type II TA, and there was probably some tension on the right pulmonary artery in our case 2. The temptation to preserve the ductus arteriosus as the communication between the ascending and descending aorta is great. Although this is satisfactory in older children [4], it is probably best avoided in neonates because the duct tissue may cause subsequent stenosis [5]. Furthermore, it would have been impossible in our cases to connect a homograft conduit from the right ventricle to the pulmonary arteries without obstruction by the large duct.
Raudkivi et al.: Truncus with Interrupted Aortic Arch
Fig. 1. Left ventricular angiogram showing the postoperative appearance in case I. The ventricular septum is intact, the proximal trunk is large, and the aortic arch has been satisfactorily repaired. Fig. 2. Right ventriculogram demonstrating that adequate continuity between the right ventricle and pulmonary artery has been provided by the homograft; there is a moderate proximal stenosis of the right pulmonary artery (case 1).
During the last few years, with the notable developments in the field of echocardiography and particularly the advent of color Doppler, we have operated on increasing numbers of infants without prior cardiac catheterization [6]. In case 1, the diagnosis was clear on echocardiography alone, but there was some doubt in case 2, requiring that cardiac catheterization be performed.
Acknowledgment. We would like to thank Mrs. Jane Ball for typing the manuscript.
119
References 1. Calder L, Van Praagh R, Van Praagh S, Sears WP, Corwin R, Levy A, Keith JD, Paul MH (1976) Truncus arteriosus communis. Clinical, angiographic and pathologic findings in 100 patients. A m Heart J 92:23 2. Di Donato RM, Fyfe DA, Puga F J, Danielson GK, Ritter DG, Edwards WD, McGoon DC (1985) Fifteen-year experience with surgical repair of truncus arteriosus. J Thorac Cardiovasc Surg 89:414-422 3. Gomes MM, McGoon DC (1971) Truncus arteriosus with interrupted aortic arch: Report of a case successfully repaired. Mayo Clin Proc 46:40-41 4. Manners JM, Monro JL, Edwards JC (1980) Corrective cardiac surgery in infants. A review of 136 patients including the contribution of postoperative ventilation. Anaesthesia 35:1149-1156 5. Monro JL (1981) Interrupted aortic arch. Techniques and results. In: Parenzan L, Crupi G, Graham G (eds) Congenital heart disease in the first three months o f life. Patron Editor, Bologna, pp 375-382 6. Sutherland GR, Colli A, Keeton BR, Monro JL, Shore DF (1987) The changing role of duplex scanning in the preoperative evaluation of congenital heart disease [Abstract]. Br Heart J 57:568
Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1990
Truncus Arteriosus with Type B Interrupted Aortic Arch: Correction in the N e o n a t e P.J. Raudkivi, G.R. Sutherland, J.C. Edwards, J.M. Manners, B.R. Keeton, and J.L. Monro Wessex Cardiothoracic Centre, The General Hospital, Southampton, UK
SUMMARY. Two neonates with truncus arteriosus (TA) and type B interrupted aortic arch are reported. In both, a homograft was used to connect the right ventricle to the pulmonary artery, while the arch continuity was established by direct anastomosis of the aortic arch to the descending aorta. KEY WORDS: Truncus arteriosus - - Interrupted aortic arch - - Homograft r e p a i r pothermic extracorporeal circulation - - Neonate
Interruption of the aortic arch occurs in about 14% of patients with truncus arteriosus (TA) [1]. The first successful repair of this lesion was reported in 1971 by Gomes and McGoon [3]: they used the ductus arteriosus to maintain continuity between the truncus and the descending aorta. Their experience with a total of seven cases with three deaths has since been updated [2]. One of these patients was less than 6 months of age. We report herein the successful outcome of surgery in two neonates with TA and type B interrupted aortic arch. A homograft was used for the right ventricle to pulmonary artery connection, and aortic continuity was provided by direct anastomosis of the arch to the descending aorta.
Hy-
stopped, the aorta cross-clamped, and St. Thomas's cardioplegic solution (20 ml/kg) injected into the aortic root. The right atrial cannula was removed and the foramen ovale closed. The descending aorta and head vessels were occluded, the pulmonary arteries detached from the truncus and the resulting truncal defect closed with a patch of dura mater. The duct was divided and all duct tissue removed from the descending aorta which was then anastomosed to the aortic arch at the base of the left carotid artery. After great care had been taken to remove air from the aortic arch, the venous cannula was reinserted and bypass recommended. After a further period of bypass, the circulation was again arrested (Table 1). The ventricular septal defect was closed with a dacron patch through a high right ventriculotomy, and continuity established between the right ventricle and pulmonary arteries with an antibiotically sterilized aortic homograft. The proximal anastomosis was finally completed during bypass as the patient was being rewarmed. Bypass was then discontinued, the cannulae removed, and the chest closed.
Methods Anesthesia was established in routine fashion [4] and the patients' nasopharyngeal temperature reduced to 28~ by surface cooling. The chest was opened by median sternotomy. Extensive dissection of the aorta, head vessels, and pulmonary arteries was performed and a single aortic and single right atrial cannula inserted. A Dideco membrane oxygenator was primed with 2 U blood, with appropriate doses of sodium bicarbonate and glucose. Maximum flow rates were 100 ml/kg/min. A short period of bypass was used to lower the temperature to 15~ during which the duct and pulmonary arteries were occluded. Bypass was
Address offprint requests to: Mr. J.L. Monro, Consultant Cardiac Surgeon, Wessex Cardiothoracic Centre, The General Hospital, Southampton, S09 4XY, UK.
Case 1 A female baby was born at 38 weeks' gestation, weighing 2.7 kg. She was noted to be tachypnoeic soon after birth and a diagnosis of TA was made. Mild truncal valve regurgitation was noted. Despite treatment with digoxin and diuretics, she remained in moderate congestive cardiac failure. However, by day 25 of life her condition deteriorated with increasing congestive cardiac failure. Two days later she required ventilation, and repeat echocardiography demonstrated a type B interrupted arch in addition to the type I TA. On the following day (March 25, 1987), she was taken to the operating room without prior cardiac catheterization, weighing 2.4 kg. Correction was carried out as described above. The smallest available antibiotically sterilized homograft was 23-mm internal diameter, and this was narrowed to a 14-mm
118
Pediatric Cardiology Vol. 11, No. 2, 1990
Table 1. Clinical and bypass data of two neonatal cases of truncus arteriosus (TA) with type B interrupted aortic arch
Age Weight Diagnosis
Temperature of arrest Duration of first arrest Duration of second arrest Total bypass time
Case 1
Case 2
28 days 2.4 kg Type I TA, mild truncal valve regurgitation Type B interrupted aortic arch, anomalous right subclavian artery from descending aorta 16~ 31 21 123 min
14 days 2.2 kg Type II TA Type B interrupted aortic arch
internal diameter bicuspid valve by removing the right coronary cusp and appropriate aortic wall. Four hours postoperatively, she suddenly became severely hypotensive and required a short period of external cardiac massage, responding to inotropic support. She was electively ventilated for 3 days and returned to the ward 9 days postoperatively, being discharged on postoperative day 16. She remains well and was restudied 8 months postoperatively. There was a 20 mmHg gradient across the aortic arch with a satisfactory repair (Fig. 1) but narrowing of the proximal right pulmonary artery (Fig. 2). The ventricular septal defect was securely closed.
Case 2 A female baby, born at 38 weeks gestation and weighing 2.4 kg, was noted to have a harsh systolic murmur. A diagnosis of TA was made by echocardiography, and she was started on digoxin and diuretics. She was transferred to this hospital on day 5 of life but remained in cardiac failure. Repeat echocardiography confirmed a type II TA and suggested the possibility of a type B interrupted aortic arch. By day 14 of life the patient was in severe cardiac failure and her weight had dropped to 2.2 kg. Cardiac catheterization was performed because we could not be absolutely certain about the interrupted arch by echocardiography alone. This confirmed a type II TA with virtually no truncal regurgitation and a type B interrupted aortic arch. Correction was carried out on the same day (December 9, 1987) in the manner described above, using a 13-mm internal diameter antibiotically sterilized aortic homograft. Postoperatively, her course was stormy with two periods of cardiac arrest which responded to resuscitation. It is possible that a rise in pulmonary vascular resistance contributed to the arrests, despite the accepted steps taken to diminish this complication. (These steps included high oxygenation, low normal carbon dioxide tension, prompt correction of metabolic acidosis, and adequate analgesia by infusion. The vasodilator and inotrope of choice were trinitroglycerine and dobutamine.) She required ventilation for 11 days postoperatively but steadily made progress and was returned to the ward on postoperative day 13. Postoperative echocardiography with color Doppler showed an
16~ 54 42 98 min
intact ventricular septal defect patch, and no significant gradient from left ventricle to descending aorta. There was a gradient of 40 mmHg across the origin of the right pulmonary artery. She was discharged from this hospital on postoperative day 26.
Discussion Since 1974 we have corrected 16 infants with TA with three deaths. Seven of them were neonates (two deaths). We have also operated on 10 infants with type B interrupted aortic arch, with one death: seven were neonates, one of w h o m died. The successful o u t c o m e in these two small, desperately ill neonates with both TA and interrupted aortic arch reflects this combined experience which includes the use of homograft conduits. We were fortunate to have a small homograft for case 2, but the technique of narrowing a homograft, as used in case 1, is most helpful and has been used in two of the other neonates undergoing repair of TA. The fact that both patients have some residual narrowing of the right pulmonary artery illustrates the considerable difficulty encountered in these very small infants in establishing a communication with the pulmonary arteries. This is particularly so in type II TA, and there was probably some tension on the right pulmonary artery in our case 2. The temptation to preserve the ductus arteriosus as the communication between the ascending and descending aorta is great. Although this is satisfactory in older children [4], it is probably best avoided in neonates because the duct tissue may cause subsequent stenosis [5]. Furthermore, it would have been impossible in our cases to connect a homograft conduit from the right ventricle to the pulmonary arteries without obstruction by the large duct.
Raudkivi et al.: Truncus with Interrupted Aortic Arch
Fig. 1. Left ventricular angiogram showing the postoperative appearance in case I. The ventricular septum is intact, the proximal trunk is large, and the aortic arch has been satisfactorily repaired. Fig. 2. Right ventriculogram demonstrating that adequate continuity between the right ventricle and pulmonary artery has been provided by the homograft; there is a moderate proximal stenosis of the right pulmonary artery (case 1).
During the last few years, with the notable developments in the field of echocardiography and particularly the advent of color Doppler, we have operated on increasing numbers of infants without prior cardiac catheterization [6]. In case 1, the diagnosis was clear on echocardiography alone, but there was some doubt in case 2, requiring that cardiac catheterization be performed.
Acknowledgment. We would like to thank Mrs. Jane Ball for typing the manuscript.
119
References 1. Calder L, Van Praagh R, Van Praagh S, Sears WP, Corwin R, Levy A, Keith JD, Paul MH (1976) Truncus arteriosus communis. Clinical, angiographic and pathologic findings in 100 patients. A m Heart J 92:23 2. Di Donato RM, Fyfe DA, Puga F J, Danielson GK, Ritter DG, Edwards WD, McGoon DC (1985) Fifteen-year experience with surgical repair of truncus arteriosus. J Thorac Cardiovasc Surg 89:414-422 3. Gomes MM, McGoon DC (1971) Truncus arteriosus with interrupted aortic arch: Report of a case successfully repaired. Mayo Clin Proc 46:40-41 4. Manners JM, Monro JL, Edwards JC (1980) Corrective cardiac surgery in infants. A review of 136 patients including the contribution of postoperative ventilation. Anaesthesia 35:1149-1156 5. Monro JL (1981) Interrupted aortic arch. Techniques and results. In: Parenzan L, Crupi G, Graham G (eds) Congenital heart disease in the first three months o f life. Patron Editor, Bologna, pp 375-382 6. Sutherland GR, Colli A, Keeton BR, Monro JL, Shore DF (1987) The changing role of duplex scanning in the preoperative evaluation of congenital heart disease [Abstract]. Br Heart J 57:568
