Two-dimensional echocardiographic and angiocardiographic diagnosis of subpulmonary stenosis due to tricuspid valve pouch in complete transposition of the great arteries.

Two-dimensional echocardiograms and angiocardiograms were obtained in six infants and children, each with complete transposition of the great arteries, a ventricular septal defect and subvalvular pulmonary stenosis. In each case, the subpulmonary stenosis resulted from redundant tricuspid valve tissue which protruded through the ventricular septal defect and into the left ventricular outflow tract. Angio-echocardiographic correlations demonstrated features that allowed preoperative recognition of this unusual type of subpulmonary stenosis. The left ventricular angiogram in an anteroposterior orientation revealed a characteristic filling defect in the outflow tract during systole in each patient. Echocardiographic images of the left ventricular outflow tract and of the tricuspid valve demonstrated subpulmonary stenosis caused by protruding redundant tricuspid valve tissue (resembling a "pouch") in all six patients. These findings were contrasted with those from three patients with normally related great arteries and a similar, but nonobstructive, tricuspid valve pouch. Echocardiographic and angiocardiographic examination and correlation allowed preoperative diagnosis of this unusual form of subpulmonary stenosis in complete transposition of the great arteries. This is especially important because limited left ventricular intraoperative exploration may fail to reveal subpulmonary obstruction as the pouch may be flaccid in a relaxed arrested heart.

Functional aortic valve atresia in transposition of the great arteries.

The criterion for the diagnosis of functional atresia of a patient semilunar valve is met when the pressure in a ventricle remains lower than that in the related great artery throughout systole so that no forward flow can occur. Functional pulmonary valve atresia has been well recognized in infants with normally related great arteries and massive tricuspid valve incompetence. The cardiac physiology and anatomy of an infant with transposed great arteries and functional aortic valve atresia is reported for the first time. The peak systolic pressure in the right ventricle was 30 mm Hg and in the aorta 64 mm Hg. The causes for right ventricular incompetence were abnormalities of the tricuspid valve and hypoplasia of the ventricular free wall. Three other cases with similar ventricular anatomy and physiology but with anatomic atresia of the aortic valve are reviewed. The possibility that under these physiologic circumstances during fetal life functional atresia develops first, and that anatomic fusion of idle semilunar cusps develops as a secondary phenomenon, is discussed.

Successful surgical repair of aortic atresia associated with normal left ventricle.

Surgical repair of aortic atresia with a large ventricular septal defect and a normally developed left ventricle was accomplished in a 14 month old infant. Palliative surgery at age 23 days consisted of bilateral banding of pulmonary artery branches and replacement of the ductus arteriosus with a Goretex conduit. Corrective surgery was accomplished by closure of the ventricular septal defect, insertion of a valved conduit between the apex of the left ventricle and the subdiaphragmatic aorta, removal of the pulmonary artery bands and division of the pulmonary-aortic conduit. The patient has a mild coarctation of the aorta and remains asymptomatic at 2 years of age.

Transposition of the great arteries with intact ventricular septum and patent ductus arteriosus.

At the time of initial balloon atrial septostomy a patent ductus arteriosus was found with angiography in 39 of 81 infants with transposition of the great arteries with intact ventricular septum. By angiographic criteria the ductus shunt was considered small in 21 infants and large and significant in 18. In contrast to the usual clinical presentation of neonates with transposition and intact ventricular septum, 12 of these 18 infants with a significant patent ductus arteriosus had only slight cyanosis and 8 presented with tachypnea out of proportion to the degree of cyanosis. Ten of the 18 infants had no continuous murmur, bounding pulses, mid-diastolic rumble or differential cyanosis. Clinically occult narrowing or closure occurred, presumably gradually and relatively late, in six infants. Acute early narrowing or closure, spontaneous (six infants) or surgically produced (three infants), occurred usually within the 1st month of life and was associated with a marked decrease in arterial oxygen saturation in eight infants, often with a rapid clinical deterioration. Persistence of a large patent ductus arteriosus for several months appears to be associated with an increased incidence of early pulmonary vascular disease. Therapeutic considerations for the infant with a large patent ductus arteriosus after initial balloon atrial septostomy include: (1) careful initial follow-up of the infant in clinically stable condition in case the ductus arteriosus should acutely narrow or close and the patient require urgent palliative or corrective surgery; (2) urgent early closure of the ductus in the infant with overt left heart failure with concurrent atrial septectomy or preferably primary corrective surgery; and (3) elective closure of a persistent significant patent ductus arteriosus before age 4 months with concurrent corrective surgery in the infant in clinically stable condition.

Discrete subvalvular aortic stenosis in childhood. Study of 51 patients.

Fifty-one children with discrete subvalvular aortic stenosis were studied between 1951 and 1974. The three anatomic types of obstruction found were the thin membranous type (43 cases), the fibromuscular collar type (5 cases) and the tunnel type (3 cases). The obstruction was usually severe, and the median left ventricular to aortic systolic pressure gradient was 90 mm Hg. Progressive obstruction with an increasing gradient was documented in 10 patients by serial cardiac catherizations. Significant associated cardiac defects, present in 57 percent of patients, often masked the typical clinical and cardiac catheterization features of subaortic stenosis. The stenosis was often not discovered until after surgery for the associated defect. Forty patients underwent surgical resection of the discrete subaortic obstruction. After surgery significant left ventricular to aortic pressure gradients can be found at postoperative cardiac catheterization. These gradients may reflect inadequate resection of the more complex discrete obstructions or represent proliferation and regrowth of the previously resected subvalvular fibrous tissue. The criteria for operability of discrete subaortic stenosis should be the angiographic demonstration of a discrete subvalvular diaphragm and the presence of a resting left ventricular to aortic systolic pressure gradient of 40 mm Hg or more.

Clinical manifestations of dynamic left ventricular outflow tract stenosis in infants with d-transposition of the great arteries with intact ventricular septum.

Four infants with d-transposition of the great arteries and intact ventricular septum who manifested early clinical symptoms and deterioration due to dynamic left ventricular outflow stenosis are presented. All four had an anatomically adequate atrial septal defect, made at the initial balloon atrial septostomy, that was later confirmed intraoperatively. Two infants continued to have a low arterial oxygen saturation level because of inadequate interatrial mixing, and one of these had severe persistent cyanosis and was treated with the Mustard operation at age 4 days. The other two infants subsequently presented with hypercyanotic spells at age 3 months. All four infants had features of dynamic left ventricular outflow stenosis on hemodynamic, angiocardiographic and echocardiographic studies. The left ventricular outflow pressure gradient was shown to increase after administration of isoproterenol in one infant, and relief of a cyanotic spell with reduction of left ventricular systolic pressure was achieved in another after intravenous administration of propranolol. The Mustard operation relieved symptoms in all infants. The effect of left ventricular outflow tract stenosis on the mechanisms responsible for interatrial mixing in d-transposition of the great arteries with intact ventricular septum is discussed.

Two dimensional echocardiographic evaluation of Mustard operation for d- transposition of the great arteries.

Two dimensional sector scan echocardiography was used to evaluate the morphologic characteristics of the surgically revised atria in 17 patients with d-transposition of the great arteries who had undergone the Mustard operation. Echocardiographic imaging of the atria was obtained from various planar projections. Dimensional measurements of various segments of the systemic and pulmonary venous atria were obtained in each patient. Correlative hemodynamic, angiographic, postmortem and echocardiographic data showed that seven patients (Group I) had no structural abnormalities of the atria. These 7 patients served as controls for 10 other patients with structural abnormalities of the surgically created atria. One patient (Group II) showed stenosis of the junction of the superior vena cava and systemic venous atrium compared with findings in the control group. Three patients (Group III) had significantly reduced echocardiographic dimensions of the junction of the anterior and posterior segments of the pulmonary venous atrium. Six patients (Group IV) had increased echocardiographic dimensions of all components of the pulmonary venous atrium due to tricuspid regurgitation. These data show that qualitative and quantitative two dimensional sector echocardiography can reliably detect structural abnormalities of the surgically revised atria after the Mustard operation.

Masked subaortic stenosis in ostium primum atrial septal defect: recognition and treatment.

Five patients with ostium primum atrial septal defect (ASD) and a cleft mitral valve had no hemodynamic evidence of left ventricular (LV) outflow tract obstruction on preoperative cardiac catheterization. After surgical closure of the ASD and repair of the mitral cleft, all 5 patients manifested subaortic stenosis with pressure gradients ranging from 10 to 120 mm Hg. Postoperative LV angiograms revealed systolic narrowing of the outflow tract, and the same outflow tract dynamics were recognized on reviewing the preoperative angiograms and echocardiograms. Persistence or exaggeration of the characteristic diastolic "goose-neck" deformity during LV systole in atrioventricular canal defects is diagnostic of a potential or actual subaortic obstruction. This diagnostic sign is also readily recognizable by 2-dimensional echocardiography, and when present, the surgeon should be alerted to explore the LV outflow tract because the outflow tract anatomy is not readily apparent at operation aimed solely at closing the ASD and repairing the cleft mitral valve.

Distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, intact ventricular septum, patent ductus arteriosus and hypoplasia of the aortic isthmus: a newly recognized syndrome.

The association of distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, intact ventricular septum and interruption or coarctation of the aortic isthmus has not previously been reported as a syndrome. This combination of anomalies was encountered in five new patients and was previously reported in three. Two patients have undergone surgery with successful results. In contrast to the sagittally oriented conventional proximal aortopulmonary septal defect, the patients in this series had a more distal type of defect, possibly representing a partial persistence of the common arterial trunk. The pulmonary arterial bifurcation may malattach to this undivided truncal segment and, as a result, the right pulmonary artery may be partially or completely shifted into the aorta. This abnormal right pulmonary arterial origin may lead to "steal" from the aortic flow during embryogenesis and to hypoplasia of the aortic arch. This concept is supported by the angiographic observation that the greater the rightward displacement of the right pulmonary artery, the greater the hypoplasia of the arch. The diagnostic angiographic sign is a strikingly high origin of the right pulmonary artery together with aortic arch hypoplasia or atresia. Closure of the aortopulmonary septal defect with implantation of the right pulmonary artery in the pulmonary trunk and repair of the aortic arch anomaly is the recommended surgical treatment.

Surgical management of anomalous left pulmonary artery causing tracheobronchial obstruction. Pulmonary artery sling.

An anomalous left pulmonary artery causing tracheobronchial obstruction is a rare malformation seen in infancy. Sixty-four cases have been described in the literature, with 17 survivors with or without surgical therapy. We reviewed the literature and the 5 cases seen at The Children's Memorial Hospital during the past 20 years. Three of these patients survived, 2 of whom have not been previously reported. The main clinical features are progressive respiratory distress, cyanosis, and apneic episodes resulting from obstruction of the lower trachea and bronchi by an anomalous left pulmonary artery. Obstructive emphysema with or without atelectasis is very common in this condition and should suggest to the clinician the possiblity of this anomaly. The important diagnostic clues are an anterior indentation of the esophagus on esophagography, narrowing of the lower end of the trachea and right bronchus on bronchography, and anomalous origin of the left pulmonary artery from the right on angiography. We prefer to approach this anomaly by a left anterolateral thoracotomy with transection and end-to-end anastomosis of the anomalous left pulmonary artery in front of the trachea. Respiratory complications due to residual tracheomalacia are common after the operation.

Pulmonary artery sling. Results of surgical repair in infancy.

Pulmonary artery sling is a rare congenital vascular anomaly in which the left pulmonary artery originates from the right pulmonary artery and encircles the right main-stem bronchus and distal trachea before entering the hilum of the left lung. This causes compression of the trachea and right main-stem bronchus, and most infants with this anomaly have severe respiratory distress within the first year of life. Between 1953 and 1990 12 infants (nine male, three female) underwent surgical repair of pulmonary artery sling. Ages ranged from 8 days to 9 months (mean age 5 months). Bronchoscopic examination was performed in all patients. Complete tracheal rings were the most common associated lesion (five patients). Nine patients had pulmonary angiography. Most recently, computed tomography and magnetic resonance imaging have been used to diagnose pulmonary artery sling and associated complete tracheal rings when present. Surgical repair consisted of transection of the left pulmonary artery at its origin and implantation into the main pulmonary artery anterior to the trachea via right thoracotomy (one), left thoracotomy (six), or median sternotomy (five). Three patients had simultaneous pericardial patch tracheoplasty for complete tracheal rings. There were no operative deaths. Two late deaths occurred, at 7 months and 2.5 years postoperatively. Of 10 long-term survivors nine have had postoperative studies to determine the patency of the left pulmonary artery. Seven anastomoses were patent (78%). Pulmonary artery sling can be repaired in infancy with low operative mortality and excellent long-term patency of the left pulmonary artery by dividing the left pulmonary artery and implanting it into the main pulmonary artery anterior to the trachea. Simultaneous pericardial patch tracheoplasty should be performed if complete tracheal rings are associated. We recommend repair at the time of diagnosis with median sternotomy and extracorporeal circulation.

Ventricular septal defect with tricuspid pouch with and without transposition. Anatomic and surgical considerations.

In a 10-year review, patients operated on for ventricular septal defect and tricuspid valve pouch were divided into two groups, because the effect of the tricuspid valve pouch is influenced by which ventricle has the higher pressure. Group I comprised patients with ventricular septal defect without transposition of the great arteries and group II, ventricular septal defect with transposition. In 72 of 392 group I patients, the septal tricuspid valve leaflet was incised to expose the edges of the hidden ventricular septal defect to accomplish proper anatomic repair. Forty-eight patients had a tricuspid valve pouch, the diagnosis being established by angiography, echocardiography, or at operation. Ages at operation ranged from 5 months to 22 years and the pulmonary-systemic flow ratio ranged from 1 to 3.4, with 16 being less than 1.5. In one patient the pouch produced a 40 mm Hg pressure gradient in the right ventricular outflow tract. At operation, through a transatrial approach, the tricuspid valve pouch was opened radially, the actual ventricular septal defect patched, and the tricuspid valve leaflet repaired. There were no deaths, no significant intraoperative or postoperative morbidity, and no tricuspid valve dysfunction. The average postoperative hospital stay was 4.8 days. In group II, six of 83 patients operated on for transposition with ventricular septal defect had significant left ventricular outflow tract obstruction from the tricuspid valve pouch. Five of six had a Mustard procedure, two requiring a left ventricular-pulmonary artery conduit, and in two of the six the ventricular septal defect was closed through the pulmonary artery. One patient had heart transplantation after a Mustard repair and tricuspid valve replacement. The sixth patient in group II had a successful arterial switch at 9 years of age, after the presence of left ventricular outflow tract obstruction was proved to be due to the pouch. The presence of a tricuspid valve pouch in group I may lead the surgeon to close false small openings produced by the pouch rather than the actual ventricular septal defect. Incising the pouch is safe and essential for proper exposure and secure closure of the true defect. In group II, the systemic right ventricular pressure can push the pouch into the left ventricular outflow tract, causing significant obstruction, and may contribute to tricuspid valve insufficiency after atrial baffle repair. Arterial switch is preferred because it returns the obstructive tricuspid valve pouch and abnormal tricuspid leaflet to the lower pressure pulmonic right ventricle.

Development of neo-coarctation in patients with transposed great arteries and hypoplastic aortic arch after Lecompte modification of anatomical correction.

We report on three patients with kinking in the proximal aortic arch that developed after Lecompte modification of the arterial switch operation. Two patients had a previous subclavian patch repair of coarctation of the aorta and had an associated hypoplasia of the transverse aortic arch, and one patient had hemodynamically mild coarctation at the anatomical repair. A severe pressure gradient across the kinked area ("neo-coarctation") necessitating reoperation developed in one patient. The acute arch angulation appears to be due to an excessive posterior displacement of the ascending aorta by the anterior relocation of either the right or left main pulmonary artery branch from underneath the aortic arch. A foreshortened and frequently hypoplastic transverse aortic arch, a common association with coarctation of the aorta, appears to be especially vulnerable to the development of "neo-coarctation" after the Lecompte modification of the anatomical repair of transposed great arteries.

Ascending aorta-right pulmonary artery shunt.

Seventy-seven patients with ascending aorta-right pulmonary artery shunt were reviewed; 48 had tetralogy of Fallot, 9 had pulmonary atresia, 11 had transposition of the great vessels with pulmonary stenosis, 4 had tricuspid atresia, and 5 had miscellaneous complex lesions. Their ages ranged from one day to 13 years. The over-all mortality rate was 17.8 per cent. Ten patients underwent total repair and takedown of the shunt with no deaths. The problems of increased pulmonary flow, pulmonary hypertension, preferential flow to one lung, kinking and distortion of the pulmonary artery, and the technical difficulties at the time of takedown were reviewed and discussed.

Transmediastinal repair of complex coarctation and interrupted aortic arch.

In the past 2 years, eight patients have had repair of coarctation of the aorta or interrupted aortic arch along with an intracardiac procedure performed through a simple midsternotomy. Five underwent total repair and three had palliation for the intracardiac lesion. Four patients did well (including one who required a resection for recoarctation), two died intraoperatively, and two died postoperatively (11 and 21 days), one of them from clostridial sepsis and the other from cerebral anoxia that followed a cardiac arrest precipitated by a massive hemoptysis. We found that with this approach the aortic obstruction could be readily relieved and the intracardiac procedure carried out. Since the majority of these patients have compromised hemodynamic status, the ease of instituting immediate bypass, avoidance of a separate incision, and feasibility of total repair are major advantages.

Vascular anomalies causing tracheoesophageal compression. Review of experience in children.

Two hundred four infants and children (mean age 13 months) have undergone operation for the relief of tracheoesophageal obstruction resulting from vascular anomalies. One hundred thirteen patients had complete vascular rings (group I), 61 with double aortic arch and 52 with right aortic arch with a left ligamentum. Nine patients had a pulmonary artery sling (group II), 71 had innominate artery compression (group III), and 11 had miscellaneous anomalies (group IV). Patients were admitted with respiratory distress, stridor, apnea, dysphagia, or recurrent respiratory infections. Diagnosis was established by barium esophagogram in group I; barium esophagogram, bronchoscopy, and computed tomography or angiography in group II; bronchoscopy in group III; and barium esophagogram or angiography in group IV. The operative approach was through a left thoracotomy in group I, II and IV (93% of these patients) and through a right thoracotomy for group III (96% of these patients). The operative mortality rate was 4.9% and there were seven late deaths (3.4%). There have been no operative deaths in patients with isolated vascular anomalies in the past 28 years. Follow-up data from 1 month to 20 years (mean 8.5 months) were available on 159 patients; 141 (92%) were essentially free of symptoms, and 12 (8%) had residual respiratory problems. Five of six patients in group II having a lung scan postoperatively had a patent left pulmonary artery. A strong index of suspicion is necessary to avoid the complications of vascular rings in children. Barium swallow is the best single diagnostic technique for patients with complete vascular rings. A bronchoscopic study is required to diagnose innominate artery compression. Angiograms or computed tomographic scans are used to confirm the diagnosis of pulmonary artery sling. Left thoracotomy provides excellent exposure for all vascular rings except the displaced innominate artery, for which a right thoracotomy is the best approach.

The surgical anatomy of pulmonary atresia with ventricular septal defect: pseudotruncus.

This is a study of 172 heart specimens with pulmonary atresia and ventricular septal defect (VSD)--pseudotruncus. These are divided into simple and complicated types. In the simple type the following may be of importance from the surgical standpoint: (1) the size of the pulmonary arteries, (2) the origin of the aorta, (3) the amount of pulmonary flow, (4) the size of the left side of the heart, (5) the presence of bronchial and/or abnormal systemic supply to the lungs, (6) the coronary circulation, and (7) the presence of intra- and extracardiac associated abnormalities. The following factors may be important in the complicated types: (1) Complete transposition may accompany the complex; (2) instead of the VSD there may be a common atrioventricular (AV) orifice; (3) the pulmonary atresia with VSD may be associated with tricuspid or mitral atresia or with common or single ventricle; (4) the entity may be associated with abnormal position of the entire heart or some of its component chambers.

Preparation of the left ventricle for anatomical correction in patients with simple transposition of the great arteries. Surgical guidelines.

Pulmonary artery banding in combination with an aortopulmonary shunt was performed on 16 patients with simple transposition of the great arteries to prepare the left ventricle for anatomical correction. Three groups were identified after operation: Group I (four patients) had increased pulmonary blood flow and tight pulmonary artery banding; Group II (four patients) had increased pulmonary blood flow and moderate pulmonary artery banding; Group III (eight patients) had normal pulmonary blood flow and moderate pulmonary artery banding. Postoperative low cardiac output was present in all patients in Group I, whereas mild heart failure was present in two patients in Group II and in two in Group III. There was one hospital death (6%). The follow-up period was 125 patient-months. Left ventricular systolic pressure rose from 63 +/- 11 torr before the operation to 101 +/- 35 torr after the procedure in Group I (p less than 0.05), from 59 +/- 10 to 93 +/- 33 torr in Group II (p less than 0.05), and from 55 +/- 10 to 84 +/- 16 torr in Group III (p less than 0.005). The increase in left ventricular muscle mass was from 44 +/- 2 gm/m2 preoperatively to 108 +/- 12 gm/m2 after operation in Group I (p less than 0.01), from 43 +/- 3 to 93 +/- 8 gm/m2 in Group II (p less than 0.02), and from 46 +/- 3 to 55 +/- 14 gm/m2 in Group III (p = no statistically significant difference). The postoperative change in left ventricular end-diastolic volume was from 100% +/- 17% to 133% +/- 23% of normal in Groups I and II (p less than 0.05) and from 123% +/- 29% to 107% +/- 36% of normal in Group III (p = no statistically significant difference). In preparing the left ventricle for anatomical correction, avoidance of severe pulmonary artery banding decreases the incidence of postoperative myocardial dysfunction, a moderate degree of volume overload and pulmonary artery banding provides the most effective stimulus for ventricular growth, and a small to moderate atrial septal defect is advantageous because it ensures the volume preload necessary for the development of the left ventricle.

Transposition of the great arteries with intact ventricular septum. Arterial switch in the first month of life.

Twenty-three infants with simple transposition of the great arteries and intact ventricular septum were operated on from October 1983 to October 1986. The age at operation in 22 infants ranged from 2 to 21 days and in one was 35 days (mean 9.82 +/- 6.86 days). The infants were evaluated with cardiac catheterization at 1 to 27 days of age. Twenty-two infants had balloon atrial septostomy, and 22 received prostaglandin E1 infusion. The left ventricular diastolic wall thickness, assessed by M-mode echocardiograms, varied between 2.8 and 4 mm. There were two hospital deaths in this group of 23 infants (mortality 8.6%), and there were no late deaths. All surviving patients are doing well clinically. One patient had asymptomatic nonsustained ventricular tachycardia necessitating phenytoin. Postoperative echocardiographic assessment performed on 15 patients at 0.93 +/- 0.61 years of age and cardiac catheterization and angiographic studies on seven patients at 1.07 +/- 0.13 years after operation revealed excellent ventricular performance, good semilunar valve function, and mild gradient at the right ventricular outflow with a mean right ventricular pressure of 37.4 +/- 4.1 torr.

Arterial switch in simple and complex transposition of the great arteries.

Arterial switch for repair of transposition of the great arteries was performed on 53 patients since October 1983. These patients were divided into three groups: group I, 25 infants with an intact ventricular septum who had primary repair in the first month of life (2 to 34 days of age, mean 9.7 +/- 6.6); group II, 13 patients with an intact ventricular septum who had anatomic repair after a preliminary procedure (pulmonary artery banding in 13, shunt in 10, atrial septectomy in 1); and group III, 15 infants with transposition of the great arteries and ventricular septal defect. In group III, six patients had Taussig-Bing abnormality, nine had previous pulmonary artery banding, three had coarctation of the aorta repaired earlier in life, and four were less than 2 weeks old. Overall early mortality was 9.4% (5/53: group I 8%, group II 7.6%, group III 13.3%). Two late deaths occurred in group II 10 and 12 weeks postoperatively after infection and high fever. A third late death 18 weeks postoperatively was due to aspiration in an infant with Goldenhar's syndrome. Mortality and morbidity decreased significantly after an initial learning period (no deaths from July 1985 to March 1987 overall, and none in the last 15 infants operated on in group I). The surviving 45 patients are doing well. All have normal sinus rhythm. Two had transient asymptomatic arrhythmias. Left and right ventricular function assessed by echocardiogram and postoperative cardiac catheterization were within normal ranges in all but two patients, one with pulmonary artery stenosis and one (Taussig-Bing abnormality with two large ventricular septal defects) with severe pulmonary vascular disease (9.6 units) observed before anatomic repair. The right ventricular pressure at catheterization ranged from 27 to 42 mm Hg in 12 patients and was 55 mm Hg in two. There was no aortic stenosis. Aortic insufficiency was trivial in three patients and mild in one. We conclude that excellent results can be obtained with arterial switch for transposition of the great arteries with or without ventricular septal defect, especially in neonates.