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1.
The optimal Fontan-type operation greatly depends on appropriate initial palliation. Several surgical techniques have been used in infancy to palliate patients with univentricular hearts, ventriculoarterial discordance, and subaortic stenosis. The two most common are pulmonary artery banding and Damus-Norwood procedures. Palliative arterial switch operation is another surgical option that was used in this early series of seven infants. The principle of this operation is to "switch" the subaortic obstruction into a subpulmonary obstruction; the coronary artery relocation on the large pulmonary trunk creates a harmonious aortic root and the connection of the rudimentary ventricular chamber to the pulmonary artery trunk creates a natural protection of the pulmonary vascular bed through the restrictive bulboventricular foramen. Seven infants with univentricular hearts, ventriculoarterial discordance, and subaortic stenosis underwent a palliative arterial switch operation. All infants had an associated aortic arch obstruction of various degrees, including one with interrupted aortic arch, five with coarctation with severe arch hypoplasia, and one with isolated arch hypoplasia. There were three with double-inlet left ventricle, three with tricuspid atresia, and one with transposition of the great arteries with ventricular septal defect and severe right ventricular hypoplasia. The subaortic obstruction was patent at birth in five patients who underwent a palliative switch operation in the first 2 months of life, and rapidly occurred following a previous neonatal pulmonary artery banding associated with arch repair in two patients who underwent a switch operation at 5 and 8 months of age, respectively. The operation includes aortic arch repair without prosthetic material, an atrial septectomy, and the arterial switch. An associated pulmonary shunt was required in five patients and a pulmonary artery banding in one. There was one early death in a patient with [S,L,L] anatomy and congenital atrioventricular block, leading to an early mortality of 14% (95% confidence limits: 1% to 28%). There was one late death. Four survivors are waiting for a Fontan-type procedure, and one survivor had satisfactory right ventricular growth. Early palliative arterial switch operation offers several advantages: reconstruction of a harmonious aortic root, natural protection of the pulmonary bed through the restrictive bulboventricular foramen, prevention of deleterious myocardial hypertrophy, and arch reconstruction without the introduction of a foreign material. This aggressive technique may provide a satisfactory palliation in infants with univentricular hearts and ventriculoarterial discordance, when the bulboventricular foramen/aortic anulus ratio is less than 0.8 or when the subaortic stenosis is severe enough to be associated with an arch obstruction.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

2.
Intracardiac obstruction to the systemic circulation can develop in patients with many forms of congenital heart disease. When transposition of the great arteries accompanies tricuspid atresia, narrowing of the ventricular septal defect (VSD) leads to subaortic stenosis. In a similar fashion, a restrictive bulboventricular foramen compromises systemic arterial outflow in patients who have single left ventricle with subaortic outflow chamber. The same effect can be seen in VSD closure in mitral atresia with normally related great vessels. Although some forms of single ventricle can be treated by ventricular septation, the modified Fontan procedure can be more generally applied to this entity. Pulmonary vascular resistance must be low, however, which excludes the application of the Fontan principle in infants. While pulmonary artery banding may protect the lungs from the development of excessive pulmonary vascular resistance, it may also accelerate the development of subaortic obstruction. We have successfully applied the Norwood operation, as described for hypoplastic left heart syndrome, to palliate subaortic stenosis due to restrictive VSD in 3 infants with single ventricle or atrioventricular valve atresia. Consideration should be given to a primary Norwood procedure in infants with single ventricle in whom subaortic stenosis is likely to develop. Patients who do receive pulmonary artery bands should be followed closely for the development of subaortic stenosis and should undergo an early, physiologically corrective operation if it occurs.  相似文献   

3.
The Damus-Stansel-Kaye procedure has been applied for the relief of outflow tract obstruction caused by a restrictive bulboventricular foramen or subaortic stenosis in patients with complex univentricular heart disease. The procedure may also be part of a biventricular repair of a Taussig-Bing transposition of the great arteries. This report details technical modifications of the procedure to ensure unobstructed blood flow from the pulmonary artery to the aorta and to maintain the integrity of the pulmonary and aortic valves.  相似文献   

4.
The clinical, hemodynamic, angiocardiographic, and postmortem findings of a previously unreported type of subaortic stenosis are presented in two patients who also had straddling tricuspid valve and transposition of the great arteries. The subaortic stenosis became apparent after banding of the main pulmonary artery and was due to hypertrophy of a probably abnormally positioned moderator band resulting in a double-chambered right ventricle. Fibrous tissue accumulation at the stenotic os infundibuli also contributed to the subaortic obstruction. Both patients had situs solitus of the atria. Patient 1 had ventricular inversion (L-loop ventricles) and atresia of the right-sided mitral valve. Patient 2 had normally positioned ventricles (D-loop) and two atrioventricular valves. The presence of a large left ventricle and a small right ventricle in the angiocardiogram led to the erroneous diagnosis of a single left ventricle with an infundibular outlet chamber in both patients. Consequently, the subaortic obstruction was thought preoperatively to be at the site of a restrictive bulboventricular foramen. Patient 1 died 36 hours after placement of a valved conduit from the left ventricle to the descending aorta. Patient 2 was operated on successfully and the surgical procedures performed are described.  相似文献   

5.
BACKGROUND: Achieving unobstructed blood flow from the systemic ventricle to the aorta is important during the Fontan procedure for complex cyanotic congenital heart disease when there is systemic ventricular outflow obstruction (SVOO). Because SVOO can progress after the Fontan procedure if there is morphologic obstruction, we have adopted a policy of relieving obstructions to systemic blood flow. METHODS: Twenty-five patients were treated by the Fontan procedure with SVOO. Twenty-one patients had undergone prior pulmonary artery banding and 10 patients had undergone prior arch repair. Systemic ventricular outflow obstruction progressed in 5 patients after the Fontan procedure. Main diagnosis was single ventricle in 12, tricuspid atresia in 5, transposition of the great arteries in 4, double-outlet right ventricle in 3, and common atrioventricular canal in 1. Mean age at operation was 6.5 years (range 1 to 15 years) and the average preoperative pressure gradient across the ascending aorta and systemic ventricle was 29 mm Hg (range 0 to 100 mm Hg). The Damus-Kaye-Stansel procedure was performed in 18 patients (double-barrel anastomosis in 13, end to side anastomosis in 5), and subaortic resection or ventricular septal defect or bulboventricular foramen enlargement was performed in 7. Double-barrel anastomosis has been our first choice since 1994, if the pulmonary valve is intact. Follow-up has ranged from 4 months to 14 years (average 5.0 years). Twenty-three of the 25 patients have undergone recatheterization (average 21.4 months later). RESULTS: No early deaths were found; one late death was reported of a patient with single right ventricle (4.0%). The postoperative average pressure gradient was 1.1 mm Hg (0 to 10 mm Hg), and the average right atrial pressure was 14 mm Hg (9 to 20 mm Hg). In all patients who underwent ventricular septal defect or bulboventricular foramen enlargement, regular sinus rhythm was maintained postoperatively. Regarding the Damus-Kaye-Stansel procedure, there was minimal progression of semilunar valve insufficiency except in 1 patient who underwent end-to-side anastomosis with moderate pulmonary regurgitation postoperatively. CONCLUSIONS: The midterm results of the Fontan procedure with SVOO have been satisfactory. Because SVOO might progress after the Fontan procedure if there is morphologic obstruction, an appropriate strategy to relieve obstruction to systemic blood flow should therefore be performed concomitantly with the Fontan procedure.  相似文献   

6.
A staged surgical approach was developed for the management of hearts with univentricular atrioventricular connection (double-inlet left ventricle or tricuspid atresia) and discordant ventriculoarterial connection with anatomical substrate for the development of subaortic stenosis. This consisted of initial palliation with pulmonary artery banding, followed by early elective relief of subaortic obstruction using a proximal pulmonary artery to ascending aorta anastomosis in infancy. Pulmonary blood flow was maintained at this time by creating a bidirectional superior cavopulmonary anastomosis. Over an 18-month period, 5 children, including 4 seen in the first week of life with aortic arch obstruction, were palliated with this approach. All patients survived operation and are asymptomatic with transcutaneous oxygen saturations of 80% to 85%. Completion of cavopulmonary repair is planned at 2 years of age. Although some authors have considered pulmonary artery banding contraindicated in these infants, the current staged approach offers an attractive alternative to the construction of a pulmonary artery to aorta anastomosis in the neonatal period.  相似文献   

7.
Background: The surgical approach of neonates with a functionally univentricular heart, transposition of the great arteries and excessive pulmonary bloodflow remains a challenge. Pulmonary artery banding remains a valuable option, but may induce ventricular hypertrophy, restriction of the bulboventricular foramen and dysplastic changes of the pulmonary valve. These secondary changes might compromise a later Damus–Kaye–Stansel connection because of pulmonary regurgitation but also a subsequent Fontan repair because of ventricular hypertrophy. The aim of this study is to investigate whether a previous pulmonary artery banding might compromise the function of a Damus–Kaye–Stansel connection. Methods: Thirteen neonates underwent pulmonary artery banding for functionally univentricular heart, transposition of the great arteries and pulmonary hypertension. Coarctation repair was associated in seven patients. All but one survived the operation. The twelve survivors underwent at a second stage a Damus–Kaye–Stansel connection after a mean interval of 1.1 years. The length of this interval was dictated by the degree of ventricular hypertrophy, the restriction of the bulboventricular foramen and by the degree of cyanosis. The Damus–Kaye–Stansel connection was constructed without any foreign material and with resorbable sutures. Associated procedures were: Glenn/hemi-Fontan (8 pts), Blalock-shunt (2 pts), biventricular correction with a homograft (1 pt), Fontan repair (1 pt). Four patients underwent successfully a Fontan repair at a third stage; seven patients are waiting for such repair. Results: All patients survived the second and third stage of this surgical approach. The mean follow-up after the Damus–Kaye–Stansel connection was 2.5 years. Echocardiography at the last follow-up revealed: PR grade 0 (1 pt), grade 1 (8 pts), and grade 2 (3 pts). All patients – except one patient with a systolic gradient of 24 mmHg – had laminar flow without any gradient in the ascending aorta. All patients, including those who underwent a definitive repair, are doing extremely well. Conclusion: This experience demonstrates that a neonatal pulmonary artery banding does not compromise the function neither of a Damus–Kaye–Stansel connection nor a Fontan repair.  相似文献   

8.
An 8-year-old girl with single ventricle and 1-transposition developed severe stenosis of the bulboventricular foramen. This became critical subsequent to pulmonary banding and a modified Fontan operation. Successful relief of the obstruction was achieved by placing a valved conduit between the ventricle and ascending aorta, thus bypassing the obstruction.  相似文献   

9.
In the setting of a single ventricle, subaortic stenosis may be enhanced by pulmonary artery banding and may later contraindicate a Fontan operation. The Norwood operation may prove a preferable alternative in some infants as a preparatory procedure. We have successfully used this procedure as the initial operation to palliate a newborn with tricuspid atresia, transposition of the great arteries, coarctation, and severe arch hypoplasia secondary to a restrictive bulboventricular foramen.  相似文献   

10.
A surgically corrected case of tetralogy of Fallot with anomalous origin of left pulmonary artery from the ascending aorta is presented. The patient was under-developed 3-year-old girl. She weighed only 1,000 grams at birth and had a systolic heart murmur and slight cyanosis. Echocardiography demonstrated the features of tetralogy of Fallot shortly after birth. Chest roentgenogram showed right ventricular enlargement, but vascular marking of lung was almost normal. Catheterization and cineangiography demonstrated the findings of tetralogy of Fallot. Final diagnosis of anomalous origin of left pulmonary artery from ascending aorta was confirmed by aortography. Surgical correction was accomplished using cardiopulmonary bypass with surface cooling. The left pulmonary artery was detached from the aorta and anastomosed to the main pulmonary artery. Pulmonary valve stenosis and severe infundibular hypertrophy were corrected, and ventricular septal defect was closed with a patch. Postoperative recovery was uneventful. On follow up after surgery, she appears to be in very good condition.  相似文献   

11.
Twelve children were identified with subaortic stenosis after Fontan's operation. All had absent resting and isoproterenol-provoked pressure gradient before the Fontan procedure. Six had a univentricular heart of left ventricular morphology, three had a single ventricle of right ventricular morphology, one had tricuspid atresia with transposition of the great arteries, one had pulmonary atresia, intact ventricular septum, and hypoplastic right ventricle, and one had corrected transposition with hypoplastic systemic ventricle. The median interval between the Fontan operation and the recognition of subaortic stenosis was 2.5 years. Ten patients underwent surgical treatment after a prior Fontan operation: Five had myectomy and enlargement of ventricular septal defect with two operative deaths; two had placement of a valved conduit from the ventricular apex to the descending aorta, and both died postoperatively; two with single ventricle had subaortic myectomy, and one had enlargement of ventricular septal defect and pulmonary aortic connection. Complete heart block developed in only one patient. Postoperative testing with Doppler echocardiography with color flow imaging demonstrated good relief of subaortic stenosis. All six children who survived the operation are well 4 months to 4 years later. Subaortic stenosis is a progressive lesion that may develop after a Fontan operation. Its surgical treatment continues to carry a significant mortality. Myectomy and enlargement of ventricular septal defect achieve direct relief of the obstruction with minimal risk of heart block.  相似文献   

12.
BACKGROUND: In patients with univentricular atrioventricular connection and the aorta originating from an incomplete ventricle, subaortic stenosis is generally due to a restrictive ventricular septal defect (RVSD), that may be present at birth or develop after palliative procedures. In particular, a primary role in the genesis of the RVSD has been ascribed to pulmonary artery banding (PAB). The aim of this paper is to analyse the possible risk factors for the development of an RVSD, including PAB, and the results of one of the proposed procedures for treatment of this condition (RVSD enlargement). METHODS: We retrospectively reviewed clinical records and outpatient records of 24 consecutive patients with univentricular atrioventricular connection and the aorta originating from the incomplete ventricle that received their first treatment at our institution from January 1991 to April 2000. The variables age, sex, weight, diagnosis, surgical procedures, associated anomalies, associated surgical procedures, were considered. RESULTS: Four patients (16.7%) had absent left atrioventricular connection, seven (29.7%) had absent right atrioventricular connection and discordant ventriculo-arterial connection, and 13 (54.7%) had double inlet left ventricle and discordant ventriculo-arterial connection. Five patients (20.8%) had associated coarctation or hypoplasia of the aorta, and eight (33.3%) had pulmonary stenosis or atresia. Median age at the first operation was 7.5 days (range: 1-376). Median weight was 3.5 kg (range: 1.9-6.3). Seventeen patients underwent pulmonary artery banding, one underwent a Damus-Kaye-Stansel connection, one received a Glenn shunt and five a modified Blalock-Taussig shunt. Early mortality was 12.5%. The only variable associated with operative mortality was the presence of coarctation or hypoplasia of the aorta (P=0.004). Ten patients (41.6%) developed subaortic stenosis. None of the tested variables, including pulmonary artery banding, was associated with the development of subaortic stenosis. Subaortic stenosis was due to a restrictive VSD in eight patients, six of whom underwent direct VSD enlargement by muscular resection and are well at last follow-up (four complete repairs). None of the procedures was complicated by complete heart block. In two cases subaortic stenosis was treated by a Damus-Kaye-Stansel connection. A single patient died during follow-up, and 11 patients have achieved a complete one-ventricle repair. CONCLUSION: In our experience, pulmonary artery banding was not associated with an increased risk of developing an RVSD. VSD enlargement proved to be safe and effective for treatment of subaortic stenosis due to an RVSD.  相似文献   

13.
BACKGROUND: In patients with a univentricular arteriovenous connection, transection of the main pulmonary artery may be performed as part of a bidirectional cavopulmonary shunt or Fontan procedure. The proximal stump of the pulmonary artery may remain in the systemic circulation. In cases with a discordant ventriculoarterial connection, subsequent restriction of the bulboventricular foramen may lead to subaortic stenosis. The subaortic stenosis can be corrected in some patients by directing the systemic flow through a combined nonobstructed aortopulmonary outlet, as in the Damus-Kaye-Stansel connection. Previous closure of the pulmonary artery has been considered by some investigators to be a relative contraindication to the Damus-Kaye-Stansel procedure, unless an allograft root can be added to the circuit after excision of the closed pulmonary stump. METHODS: Three patients with previously transected pulmonary arteries underwent a modified Damus-Kaye-Stansel connection using the native pulmonary valve and the proximal pulmonary artery stump. RESULTS: The native pulmonary valves have functioned well despite thrombus formation in the proximal stump in 2 patients before Damus conversion. All 3 patients are alive and well after 108, 19, and 3 months, with competent nonobstructed ventriculoarterial connections. CONCLUSIONS: If transection and closure of the pulmonary artery as part of a previous palliation has spared the pulmonary valve, then the native pulmonary outlet might be used for a safe Damus-Kaye-Stansel connection.  相似文献   

14.
BACKGROUND: We set out to examine the long-term results of relief of subaortic stenosis by enlargement of ventricular septal defect in patients with univentricular atrioventricular connection to a dominant left ventricle and discordant ventriculoarterial connections. METHODS: Twenty-four patients underwent enlargement of ventricular septal defect between 1985 and 1998 at a median age of 3.2 years (range, 3 weeks to 14 years). Ten patients were younger than 1 year of age. Eighteen had undergone previous banding of the pulmonary trunk, 9 of whom also required repair of coarctation of the aorta. The median subaortic gradient before enlargement was 46 mm Hg. Twenty-three patients had a patch to enlarge the rudimentary right ventricle. RESULTS: Five patients (21%) died in the early postoperative period. The overall survival at 1 and 3 years was 73%, and at 5 and 10 years was 68% and 60%, respectively. Complete heart block requiring insertion of a pacemaker occurred in 2 patients (8%). A Fontan operation was performed in 10 patients, 5 underwent a bidirectional Glenn procedure, and 2 required cardiac transplantation. Follow-up was complete in all survivors at a median time of 6.7 years (range, 8 months to 13 years). From the earlier part of the series, 3 patients experienced aortic insufficiency and 2 had recurrent obstruction. Factors adversely affecting survival were age younger than 1 year at operation and presence of obstruction within the aortic arch. CONCLUSIONS: Our experience shows that, in patients with univentricular atrioventricular connection to a dominant left ventricle and subaortic stenosis, enlargement of the ventricular septal defect provides satisfactory relief of obstruction except in those younger than 1 year of age, and those who have associated obstruction in the aortic arch.  相似文献   

15.
Four specimens of univentricular hearts of the right ventricular type, three with two atrioventricular valves and one with a common valve, have been examined histologically to identify the atrioventricular conduction system. Three of the specimens were initially thought to have only one chamber within the ventricular mass, a chamber which had a right ventricular trabecular pattern. On detailed examination and with removal of blocks of tissue for histologic study, a second, rudimentary chamber was found in the posterior ventricular wall. This chamber had a trabecular zone of the left ventricular type and was connected with the main chamber only via a small defect in the septum which separated the two chambers. In all four cases the connecting atrioventricular node was dound in normal relationship to atrial markers and the penetrating bundle descended onto the posterior wall of the main chamber. In three cases it ran along the crest of the septum between the main chamber and rudimentary chamber, in relation to the septal defect. In two cases left bundle branch tissue was identified running into the rudimentary chamber. This pattern of conducting system is different from that previously identified in other varieties of univentricular heart and again underlines the importance of intraoperative mapping of the conduction system during surgery of the univentricular heart.  相似文献   

16.
Ten patients underwent palliative surgery for interrupted aortic arch and severe subaortic obstruction due to posterior displacement of the conal septum. Their ages ranged between 4 and 28 days (mean, 11.0 +/- 7.7 days) and their weights, between 2.1 and 4.2 kg (mean, 2.85 +/- 0.6 kg). Preoperative echocardiography and cardiac catheterization were performed on all patients. The ratios of the left ventricular outflow tract diameters and the ascending aortic diameters to the descending aortic diameters were 0.56 +/- 0.03 and 0.56 +/- 0.06, respectively, compared with 0.81 +/- 0.12 and 0.95 +/- 0.17, respectively, in 20 patients with interrupted aortic arch but without obstruction (p less than 0.001). Four of the 10 patients underwent pulmonary artery banding and insertion of a bypass graft between the ascending and the descending aorta. All 4 died of low cardiac output soon after operation (100% operative mortality). The remaining 6 patients underwent banding and insertion of a graft between the main pulmonary artery proximal to the band, and the descending aorta. All of these patients survived, and all except 1 are doing well 3 months to 4 years postoperatively. The use of a pulmonary artery-descending aorta conduit and of distal pulmonary artery banding provides good palliation for patients with interrupted aortic arch and major subaortic stenosis.  相似文献   

17.
A two-stage surgical procedure was performed in a young adult with pulmonary atresia and a ventricular septal defect with upper lobe pulmonary artery flow from confluent central pulmonary arteries and lower lobe pulmonary blood flow originating from two large systemic-pulmonary collaterals. Initially a Dacron Y graft was anastomosed between the ascending aorta and the collaterals and a graft to the left pulmonary artery. At the second operation, continuity was established between the right ventricle and the Y graft by using a valved Dacron conduit and the ventricular septal defect was closed.  相似文献   

18.
OBJECTIVE: Although the influence of small left heart structures on outcome of a biventricular repair in neonatal critical aortic stenosis is well documented, little is known about its effect in neonates with aortic arch obstruction and coarctation. The purpose of this study was to evaluate the influence of small left heart structures on early and late results of repair and the ability to achieve a biventricular repair in neonates with coarctation and aortic arch obstruction. PATIENTS: Neonates included in this study had a left ventricular adequacy score (as proposed by Rhodes and associates for critical aortic stenosis) that would have predicted a need for a univentricular (Norwood) repair. All were ductus dependent but had antegrade ascending aortic flow and a small but nonstenotic aortic valve (<30 mm Hg gradient). Twenty neonates aged 10 +/- 9 days were identified for the study with weights averaging 3. 1 +/- 0.6 kg. Selected left heart measurements obtained by preoperative echocardiography included the following: aortic anulus 5.3 +/- 0.3 mm, mitral anulus 8.4 +/- 1.0 mm, transverse aortic arch 3.4 +/- 0.6 mm, and left ventricular volume 25 +/- 4 mL/m2. All patients underwent coarctation repair by resection and extended end-to-end anastomosis to enlarge the transverse arch as needed. Three patients underwent simultaneous pulmonary artery banding because of a hemodynamically significant ventricular septal defect. These 3 patients have subsequently had their defects successfully closed without mortality. RESULTS: There were no early or late deaths at a follow-up of 38 +/- 16 months after the operation. Three patients (3/20, 15%) have had to undergo reintervention with balloon aortoplasty because of recurrent coarctation (gradient > 20 mm Hg) in 2 and resection of subaortic stenosis in 1. Late follow-up in the remaining patients reveals 1 with moderate subaortic stenosis (gradient = 43 mm Hg), 2 with mild aortic stenosis (gradient < 30 mm Hg), and 2 with mild to moderate mitral stenosis. At late follow-up, 16 patients (16/20, 80%) are completely free of symptoms and 4 (4/20, 20%) have mild residual symptoms. CONCLUSIONS: Biventricular physiology can be successfully achieved in neonates with small left heart structures and aortic arch obstruction with minimal mortality and excellent late functional results. Standard echocardiographic measurements used to predict the need for a univentricular repair in critical aortic stenosis are not valid for the neonate with aortic arch obstruction.  相似文献   

19.
A 73-year-old man with a severely stenosed bicuspid valve and an aneurysm of the ascending aorta underwent valve and aortic surgery. Preoperative imaging revealed a single coronary artery arising from the right side of the sinus of Valsalva and a branch that perfused into the left side of the heart to pass through the front of the pulmonary artery. We replaced the aortic valve and ascending aorta, painstakingly avoiding damage to the coronary artery and obstruction of the sole coronary ostium.  相似文献   

20.
Five patients with tricuspid atresia, normally related great arteries, and decreased pulmonary flow underwent reconstruction of the right ventricular outflow tract or enlargement of the ventricular septal defect (VSD) (outlet foramen) or both in order to increase pulmonary blood flow. The age of the patients ranged from 9 months to 4 years.All patients previously had had a systemic-pulmonary artery anastomosis. Preoperative mean arterial oxygen saturation was 67.2%. A restrictive outlet foramen was enlarged in 3 patients. Infundibulectomy and enlargement of the outlet chamber with a Dacron patch were performed in 4 patients. A pulmonary valve commissurotomy alone was done in 1 patient. There were no hospital or late deaths (mean follow-up, 16 months). Four patients out of 5 have obtained symptomatic and documented (increase in partial pressure of oxygen) benefit. In 1 patient, arterial oxygen saturation failed to rise to a satisfactory level.The surgical approach and the importance of recognition and treatment of any site of obstruction to pulmonary flow, including a restrictive VSD, are stressed.  相似文献   

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