Pulmonary Collaterals Research Articles

Recanalisation of bilateral superior vena cava after total cavopulmonary connection

Formation of systemic to pulmonary venous or systemic venous left atrial collaterals frequently occurs in patients after Glenn or Fontan-type operations. Embolization with detachable metal coils is the therapy of choice for the closure of small vessels. These devices however are not appropriate for the occlusion of large collaterals, e. g. recanalized bilateral caval veins. We report two patients who presented late after Fontan-type operations with a gradual decrease in oxygen saturation due to recanalisation of bilateral caval veins. Interventional closure of these large veins was carried out successfully with the use of 8 mm Amplatzer muscular VSD Occluders, resulting in an increase of arterial oxygen saturations. The closure of recanalized bilateral superior caval veins after Fontan procedures is possible without technical problems by means of the Amplatzer muscular VSD Occluder. In order to avoid future formation of venous collaterals via the azygos or hemiazgos system, the occluder should be placed in the vena cava below the orifice of the azygos/ hemiazygos vein.

Pulmonary atresia, ventricular septal defect, and multiple aorta pulmonary collateral arteries

Pulmonary atresia with ventricular septal defect and major aorta pulmonary collaterals arteries is a rare and complex congenital cardiac defect. There is considerable variability in the anatomy, morphology, and geometry of the native pulmonary arteries and the collateral vessels. While the ultimate goal of therapy is a biventricular correction with complete unifocalization, establishment of right ventricular to pulmonary arterial continuity, and closure of all intracardiac defects, achieving this endpoint can be frustrating and difficult. A carefully considered approach for each individual patient is required. Patients with appropriate anatomy may undergo a definitive single-stage unifocalization and biventricular correction in early infancy. Patients with less favorable anatomy will require a more eclectic approach. While our knowledge of the genetics of this defect is rudimentary, further advances in genetic understanding and technology hold tremendous promise for the development of future therapies.

Characterization and treatment of systemic venous to pulmonary venous collaterals seen after the Fontan operation

To determine the anatomical characteristics of systemic venous collaterals formed after the Fontan operation, and the efficacy of a transcatheter strategy for management. We reviewed retrospectively the data from cardiac catherization of 50 persistently cyanotic patients after the Fontan operation. A total of 54 transcatheter interventions were performed, at a mean age of 6.3 +/- 3.5 years, a mean interval of 2.7 +/- 2.9 years from completion of the Fontan circulation. Of 38 patients who had fenestration of the baffle at the time of surgery, 25 had patency of the fenestration, and 24 had the fenestration occluded with a device at the time of interventional treatment for associated venous collaterals. We identified a total of 68 systemic venous collateral channels, of which 36 (53%) were supracardiac, 12 (18%) cardiac, and 20 (29%) infracardiac in origin. The most common site of origin was the brachiocephalic vein (44%), followed by the left phrenic vein (25%). A longer time from surgery, at 3.3 +/- 3.4 years, was associated with the identification of collaterals having a diameter larger than 4 mm (p < 0.01). The mean pulmonary arterial pressure was higher in those with larger compared to those with smaller collaterals (13.3 +/- 2.8 versus 11.1 +/- 2.0 mmHg, p < 0.01). Coils were used for occlusion of 61 vessels, and a Rashkind occluder for the remaining 7. After exclusion of the patients undergoing simultaneous closure of their fenestration, systemic saturation of oxygen increased from 89 +/- 6% to 95 +/- 3% (p < 0.01). Venous collateral channels are common in patients suffering progressive cyanosis in the setting of the Fontan circulation. The collaterals increase in size with time, and are associated with higher pulmonary arterial pressures. Transcatheter treatment is feasible, and results in resolution of cyanosis. Only continuing follow-up will show whether further collateralization occurs in time.

Pulmonary atresia with ventricular septal defect, extremely hypoplastic pulmonary arteries, major aorto-pulmonary collaterals.

Among 63 patients with pulmonary atresia and ventricular septal defect (VSD), 10 patients with extreme hypoplasia of the pulmonary arteries (PA) (mean Nakata index 20.6 mm(2)/m(2)), but with confluent arteries and a diminutive main PA, and major aorto-pulmonary collaterals (MAPCAS), have been submitted to a 'rehabilitation' of the PA with several stages: (i) connection between RV and PAs, (ii) interventional catheterizations, (iii) complete correction with or without unifocalisation. We report here the results of this approach. The RV-PA connection was direct (nine cases) or with an homograft conduit (one case), done under normothermic cardiopulmonary by-pass in patients aged 4.9 months (range 0.1-18 months). Subsequently, six underwent interventional catheterizations (dilations and stents in the PA, MAPCAS occlusion by coils). Complete correction was done in seven patients (mean age 30 months, range 8-49). One patient is awaiting correction. One patient died after the first stage. All patients having had the third stage had a satisfactory development of the PA, had a complete closure of the VSD and a satisfactory reconstruction of the PA bifurcation. There was one death of severe pulmonary infection 6 months after repair. All other patients have been followed by catheterization and/or echocardiograms. With a follow-up of 83+/-65 months, all patients are improved, 50% have no cardiac medications, none has residual shunt, RV/LV pressure ratio is 0.6 (range 0.3-1). The strategy of 'rehabilitation' of PA allowing: (i) antegrade flow in the PA, (ii) interventional catheterizations, (iii) growth of the PA with possible angiogenesis, (iv) complete correction, is a logical approach to be undertaken in the young patient and is a valid alternative to strategies relying more on MAPCAS for pulmonary vascular supply. The therapeutic sequences depend upon the individual anatomy.

The management of pulmonary atresia, ventricular septal defect, and multiple aorta pulmonary collateral arteries by definitive single stage repair in early infancy.

The management of infants and children with pulmonary atresia, ventricular septal defect, and multiple aorta pulmonary collateral arteries (PA/VSD/MAPCA) has proven to be challenging. Therapeutic approaches have included staged unifocalization, shunting, coiling of collateral vessels, and heart/lung transplantation. Results have been variable and frustrating. Hoping to take advantage of growth potential in pulmonary segments supplied by MAPCA, a more radical approach was adopted in March of 1997. This consists of single stage complete unifocalization with closure of the ventricular septal defect and establishment of right ventricular to pulmonary arterial continuity with a cryopreserved pulmonary allograft (Rastelli type correction) through a midline sternal incision. During an 18-month period, eleven consecutive infants with PA/VSD/MAPCA underwent complete surgical correction. The ages ranged from 5 days to 5 months. Weights ranged from 2.2 to 5.6 kg. Through a standard median sternotomy incision, the pericardium and both pleural spaces were opened. Normothermic cardiopulmonary bypass was instituted. Section of all collaterals was accomplished without hypoxemia, and all collaterals were ligated at their origin from the aorta. They were then brought through posterior mediastinum to construct a pulmonary artery confluence. The ventricular septal defect was closed, and continuity was established between the right ventricle and the newly created pulmonary artery confluence with cryopreserved allografts. Ten of 11 patients survived operation, with postoperative courses that were uncomplicated. Length of stay ranged from 7-16 days, with a median length of stay of 11 days. One perioperative death occurred in a patient with preoperative co-morbidities of necrotizing enterocolitis, with no functioning gastrointestinal tract, intraventricular hemorrhage, and ventilator dependency since birth. At angiography, this patient has no demonstrable central pulmonary arteries and multiple diminutive aorta pulmonary collaterals. Autopsy revealed no demonstrable pulmonary arteries within the pulmonary parenchyma. All patients have been followed closely, and have grown normally. Two patients undergone repeat cardiac catheterization because of the echocardiographic demonstration of right ventricle pressures that had exceeded 50% of systemic. Both patients were treated with balloon angioplasty and one of these patients has had stenting of stenotic pulmonary arterial segments. No other patients have required additional hospitalization. Right ventricular pressures have remained less than fifty percent of systemic by echocardiographic assessment in all other patients. We feel that a single stage correction of pulmonary atresia, ventricular septal defect, and multiple aorta pulmonary collateral arteries can be accomplished in early infancy with acceptable morbidity and mortality. The initiation of normothermic cardio-pulmonary bypass greatly facilitates dissection of collaterals and prevents hypoxemia. Interventional cardiology with balloon angioplasty and stenting of abnormal pulmonary arterial segments is both an important essential adjunct in the management of these patients. We remain optimistic that a single stage approach to this complex lesion coupled with cardiac catheterization, balloon angioplasty, and stenting, will provide long-term results superior to staged approaches.

Coronary to pulmonary artery collaterals in patients with pulmonary atresia and ventricular septal defect

Background. The frequency, distribution, and surgical importance of coronary artery to pulmonary artery (CAPA) collaterals have not been established. The aim of this study was to establish prevalence, anatomical pattern, and significance of CAPA in patients with pulmonary atresia and ventricular septal defect (PA/VSD). Methods. We reviewed cardiac catheterization and operative data of 87 consecutive, unselected patients who underwent one-stage complete unifocalization for PA/VSD and assessed major systemic to pulmonary collaterals from July 1992 to June 1998. Results. CAPA collaterals were diagnosed in 9 of 87 patients (10%). The collaterals originated from the left coronary artery system in 7 patients and the right in 2. Collaterals from the left coronary system arose from the left main coronary artery in 3 patients and the circumflex in 4. All collaterals joined the central pulmonary artery, which bifurcated and supplied both lungs. One collateral from the right coronary system joined the stump of the main pulmonary artery and the other gave origin to a true left pulmonary artery, which was the sole supply to 75% of the left lung. Coronary artery enlargement was seen in 2 patients only. No patient had evidence of myocardial ischemia. Coronary collaterals comprised a dual source of pulmonary blood flow in all but 1 patient. During unifocalization, the CAPA collaterals were ligated at its origin in all cases, and the collateral from the right coronary to the left pulmonary artery was unifocalized. Conclusions. The prevalence of CAPA collaterals in patients with PA/VSD is approximately 10%. The diagnosis may be missed without appropriate angiograms. We recommend selective ascending aortogram or selective coronary angiogram in all patients.

Incidence and implications of systemic to pulmonary collaterals after bidirectional cavopulmonary anastomosis

Background. Systemic to pulmonary arterial collaterals often develop after bidirectional cavopulmonary anastomosis (BCPA). It has been proposed that such collaterals may be related to perioperative outcome and duration of effusions after the modified Fontan procedure. However, the incidence and significance of collaterals after BCPA remain uncertain.Methods. To evaluate risk factors for, and significance of, such collaterals, we reviewed angiographic and clinical data for all 76 patients who underwent BCPA between January 1990 and June 1996 and had follow-up catheterization during or before 1997.Results. The median age at BCPA was 10 months, and the median duration from BCPA to follow-up catheterization was 18 months. Arterial collaterals were detected on follow-up catheterization in 45 patients (59%). Factors associated with collateral development included a prior right-sided systemic-to-pulmonary arterial shunt, lower pre-BCPA end-diastolic ventricular pressure and pulmonary vascular resistance, and use and duration of cardiopulmonary bypass during the BCPA operation. Fourteen of the 45 patients (30%) underwent coil embolization of the collaterals. Forty-three patients have undergone extracardiac conduit Fontan, with 1 early and 1 late death. Collaterals were present in 22 of these patients, 7 of whom underwent pre-Fontan embolization. The duration from BCPA to Fontan was longer in patients with collaterals, but these patients were not more likely to have prolonged effusions than those without, and the duration of tube thoracostomy was significantly shorter in patients with collaterals. Embolization of collaterals did not affect the duration of effusions.Conclusions. Systemic-to-pulmonary arterial collaterals are common after BCPA. In contrast to prior reports, collaterals were not associated with a higher incidence of prolonged effusions after the Fontan procedure in our experience, and did not correlate with poor outcome.

Systemic to pulmonary collaterals in very low birth weight infants: color doppler detection of systemic to pulmonary connections during neonatal and early infancy period.

Angiographic visualization of systemic to pulmonary collaterals (SPC) has been documented in premature infants needing prolonged ventilatory support. Noninvasive identification of such communications in premature infants was reported recently. The purpose of this study was to describe: 1) incidence, 2) clinical findings and implications, and 3) short-term follow-up of SPC diagnosed by echocardiography in very low birth weight (VLBW) infants admitted to the neonatal intensive care unit. From December 1, 1994 to August 31, 1996, 196 infants with birth weight <1500 g were admitted to the neonatal intensive care unit; 133 of them received serial echocardiographic evaluations at 1 to 2 days, at 2 weeks, and at 1, 2, and 3 months of life. Follow-up echocardiograms were scheduled at 6 months and 1 year of age for patients with SPC persisting at 3 months of age. SPC were demonstrated in 88 patients (66%) at 1 to 90 days of life (mean 28 days). In most cases, the SPC originated at the distal aortic arch or the proximal descending aorta. Ten patients (11%) were treated for congestive heart failure. The symptoms improved and anticongestive therapy was discontinued in 9. One patient with persistent congestive heart failure underwent therapeutic cardiac catheterization and 1 prominent SPC was embolized. The incidence of SPC in VLBW infants is much higher than previously reported. We postulate that SPC are bronchopulmonary communications that enlarge and/or proliferate in response to a given stimulus. These communications are associated with increased time on positive pressure ventilation and length of stay in the hospital. SPC may lead to pulmonary edema and should be searched for in VLBW infants with a more complicated course. Echocardiographic examination with color Doppler performed in premature infants to evaluate left to right shunts should include careful search for systemic to pulmonary collaterals.echocardiography, systemic to pulmonary collaterals, aortopulmonary collaterals, prematurity, pulmonary edema.

Accuracy of MRI evaluation of pulmonary blood supply in patients with complex pulmonary stenosis or atresia.

Detailed imaging of pulmonary artery (PA) anatomy and significant aorto-pulmonary collaterals (APCs) is crucial for surgical planning and follow-up in patients with complex congenital heart disease (CHD) and pulmonary stenosis or atresia. Because examination by echocardiography is often technically limited and catheterization is invasive, this study evaluated the diagnostic accuracy of magnetic resonance imaging (MRI) as an alternate non-invasive tool. Thirteen patients (median age 28 years, range: 1-44 years) underwent both cardiac catheterization and MRI within a median of two months (range 0.1-8 months). Diagnoses included tetralogy of Fallot (TOF) with pulmonary atresia (n = 8), TOF with pulmonary stenosis (n = 2), single left ventricle with pulmonary stenosis (n = 2), and complex heterotaxy with pulmonary stenosis (n = 1). The MRI sequences used in this study were ECG-gated spin echo and gradient echo sequences acquired in multiple planes. Compared to catheterization, MRI had 100% sensitivity and specificity for the diagnosis of main PA (n = 6) and branch PA (n = 13) hypoplasia or stenosis, as well as discontinuous (n = 4) or absent (n = 10) branch PAs. There was complete agreement between catheterization and MRI identification of significant APCs (n = 18). Main PA atresia was noted by MRI in four patients but was not definitively seen by catheterization in any. MRI but not catheterization precisely defined the distance between discontinuous PAs and their relationship to other mediastinal structures. In conclusion, cardiac MRI is a reliable non-invasive imaging modality to define PA and APC anatomy in patients with complex pulmonary stenosis or atresia.

Systemic to Pulmonary Collaterals in Premature Infants

Systemic to Pulmonary Collaterals in Premature Infants

Is There a Link between the Development of Systemic to Pulmonary Collaterals and Stage III or Greater Retinopathy of Prematurity in Very Low Birth Weight Infants? A Prospective Evaluation

Is There a Link between the Development of Systemic to Pulmonary Collaterals and Stage III or Greater Retinopathy of Prematurity in Very Low Birth Weight Infants? A Prospective Evaluation

HEPARIN AS A RISK FACTOR FOR PERIGRAFT SEROMA COMPLICATING THE MODIFIED BLALOCK-TAUSSIG SHUNT

Objective: The purpose of this study was to determine the risk factors associated with the occurrence of perigraft seromas complicating systemic-to-pulmonary polytetrafluoroethylene grafts. Methods: Clinical and perioperative variables were reexamined, blinded for the outcome variable perigraft seroma, in 60 patients undergoing 67 consecutive graft procedures in a 3.5-year period. Results: Eight cases of perigraft seroma were diagnosed in six patients. Univariate analysis revealed age ( p = 0.02), a diagnosis of pulmonary atresia with ventricular septal defect and systemic–pulmonary collaterals ( p = 0.001), reimplantation of collaterals during the procedure ( p < 0.001), and intravenous heparin administered after operation ( p < 0.0001) as risk factors for symptomatic perigraft seroma. Multivariable analysis defined heparin as the only significant factor associated with symptomatic perigraft seroma. Consolidation of the upper lobe on chest radiograph, ipsilateral to the shunt, directly after operation ( p = 0.01), but especially 8 to 10 days after operation ( p < 0.0001), or the need for prolonged drainage of pleural fluid ( p < 0.0001) were correlated with the occurrence of perigraft seroma. Perigraft seroma led to four early rethoracotomies in three patients and to accelerated corrective surgery in three cases. Consolidation and absent perfusion of lung segments persisted in two patients. Conclusions: Our data suggest that the use of heparin leads to an increased risk of perigraft seroma, complicating systemic–pulmonary polytetrafluoroethylene grafts. Prolonged pleural drainage and/or postoperative consolidation of the upper lobe indicate the development of symptomatic perigraft seroma. Treatment is controversial and results are unpredictable. Expectative management seems to be justified so long as permitted by the clinical condition. (J Thorac Cardiovasc Surg 1998;116:286-93)

Esophageal varices in association with unilateral pulmonary vein atresia

A 27-yr-old woman with recurrent episodes of hemoptysis (and hematemesis due to esophageal varices) was found to have unilateral pulmonary vein atresia. Reversed flow In the left pulmonary artery, a finding highly suggestive of this rare congenital anomaly, was demonstrated during cardiac catheterization. The definitive diagnosis was afforded by pulmonary wedge angiography, which not only demonstrated the atretic leftsided pulmonary veins, but also revealed a serpiginous system of systemic collateral veins to be the cause of her esophageal varices. Pneumonectomy of the nonfunctioning hypoplastic lung, the most successful approach to this disorder, may be complicated by severe bleeding of the numerous systemic arterial collateral vessels transacted during surgical mobilization of the affected lung. Percutaneously delivered vascular occlusion coils were used in this case to occlude the large systemic to pulmonary artery collateral arteries immediately prior to pneumonectomy. Intra- and perioperative bleeding was minimal, and the patient has done well without further episodes of hemoptysis or hematemesis. Percutaneous occlusion of systemic to pulmonary collaterals may prove useful as a preoperative step for other congenital heart disease patients requiring lung or heart/lung transplantation. © 1996 Wiley-Liss, Inc.

794-1 Outcome of Pregnancy in Women with Complex Pulmonary Atresia

To define the outcome of pregnancy in patients (pts)with complex pulmonary atresia (PA); i.e. PA with VSD and congenital systemic to pulmonary collaterals, we reviewed data on 76 such pts ≥16 yrs old, seen at the Mayo Clinic between 1980–92. There were 62 pts who were advised against or had not attempted pregnancy, no pts reported infertility. Fourteen pts had 24 pregnancies resulting in 10 live births, (including one twin pregnancy). There was one neonatal death due to abruptio placenta at 27 wks. Seven deliveries (including the twins; i.e. 8 births), were vaginal and 2 were by cesarean section. Six pregnancies were terminated due to unoperated maternal PA. Miscarriage occurred in 9/18 (50%) of uninterrupted pregnancies in 7 pts (3 in pts without prior cardiac surgery, 4 in pts after palliation, and 2 after complete repair). Six pts had successful pregnancies; 2 unoperated pts had 3 deliveries (including twins; i.e. 4 births), 2 palliated pts had 3 deliveries, and 2 pts had 2 successful and 2 unsuccessful pregnancies after complete repair. Two pts had preterm labor, 1 due to toxemia (twin pregnancy). One pregnancy was complicated by high RV pressure (from conduit obstruction), and 1 by CHF requiring hospitalization for the last month of pregnancy (no prior surgery). The mean maternal Hb in pts with successful pregnancy was 14.9 ± 1.3 gms vs 18.3 ± 2.1 gms in pts who terminated pregnancy (p = 0.01) and 16.4 ± 2.2 gms in pts with unsuccessful pregnancies (p = NS). No pregnancy related maternal deaths occurred. The overall mean birth weight was 2.2 kg; 2.0 ± 0.7 kg for 7 offspring of cyanotic pts vs 3.1 ± 0.3 kg for 2 offspring of pts post complete repair (p = 0.08). None of the offspring had congenital heart disease. Pregnancy in pts with complex PA can be successfully carried out but there is an increased risk of fetal loss even without maternal hypoxia (miscarriage rate 50%). Pre-pregnancy assessment of functional class, pulmonary pressures, ventricular and conduit function and degree of cyanosis should be established.

Pulmonary venous collaterals secondary to superior vena cava stenosis: A rare cause of right-to-left shunting following repair of a sinus venosus atrial septal defect

We describe a case of unusual pulmonary vein-to-vein collateral formation leading to systemic desaturation years following surgical repair of a sinus venosus atrial septal defect and partial anomalous pulmonary venous return from the right lung. At surgery, a single right upper lobe pulmonary vein branch was left draining high into the superior vena cava (SVC), resulting in a small left-to-right shunt. SVC obstruction developed at the site of the ASD repair and elevated venous pressure above the obstruction caused retrograde flow into the unincorporated pulmonary vein. Pulmonary vein-to-vein collaterals formed between this unincorporated vein and an adjacent pulmonary vein that had been surgically diverted to drain into the left atrium, resulting in a right-to-left shunt within the right lung. Normal pulmonary veins drain multiple bronchopulmonary segments, thus providing potential collateral pathways. Balloon angioplasty of the SVC stenosis successfully relieved the obstruction and abolished the right-to-left intrapulmonary shunt.

Surgical repair of hemitruncus: principles and techniques.

Ten patients have presented at the World Children's Hospital of Melbourne with hemitruncus, a form of truncus arteriosus. Nine of these patients underwent successful one- or two-stage hemodynamic repair. Early repair is carried out to avoid pulmonary vascular disease of the lung directly supplied from the trunk and to recruit as much of the contralateral pulmonary artery vasculature bed as possible is a secondary goal. The repair should be contemplated within the first six months of life to prevent severe pulmonary vasculature obstructive disease. Anatomy that is repairable in one stage is when the left pulmonary artery originates from the trunk and the complete right pulmonary artery supplied by pulmonary collaterals from the arch to the descending aorta. Anatomy requiring two-stage repair occurs when the RPA rises from the trunk and the left PDA rises from the descending aorta or distal aortic notch and either the right or the left lung blood supply is from multiple origins and requires unifocalization. With these anatomical principles and the general meticulous perioperative and postoperative care of the infants, a high degree of success should be obtainable with repair of this hemitruncus.

Novas técnicas cirúrgicas para o tratamento da atresia pulmonar com comunicação interventricular e anomalias de artérias pulmonares incluindo o assim chamado truncus tipo IV

Entre janeiro de 1975 e outubro de 1986, 42 pacientes com atresia pulmonar e comunicacao interventricular, com idade entre 2 e 18 anos, foram submetidos a correcao parcial, ou total. Foram divididos em: tipo A) com todos os segmentos broncopulmonares conectados as arterias pulmonares (AP's), 34 pacientes; tipo B) com alguns dos segmentos broncopulmonares conectados as AP's, 6 pacientes; tipo C) com todos os segmentos broncopulmonares conectados as colaterais sistemico-pulmonares, 2 pacientes. A correcao foi planejada em uma a tres etapas. No tipo A, 17 foram corrigidos em uma etapa, com tres obitos; em 9, na primeira etapa, as AP's foram reconstruidas e o Blalock (BT), realizado, tendo ocorrido um obito. Em 2, a segunda etapa de correcao total foi realizada, sem obitos. No tipo B, a primeira etapa de unificacao das colaterais intra ou extra-hilares foi realizada em 6 casos, sem obitos; em 2, a segunda etapa da correcao total foi realizada, com um obito. No tipo C, 2 pacientes foram operados; 1 em tres etapas; a primeira constou de construcao de segmento arterial intermediario entre as arterias lobares e o BT; a segunda compreendeu unificacao das colaterais contralaterais e a terceira, restabelecimento da continuidade ventriculo direito - circulacao pulmonar; o paciente teve boa evolucao. No segundo caso, a correcao foi realizada apos somente uma intervencao previa. A evolucao foi satisfatoria. Estudos hemodinâmicos seriados foram realizados em 32 pacientes. As tecnicas propostas permitem obter condicoes para correcao total com adequada relacao pos-operatoria das pressoes ventriculo direito - ventriculo esquerdo.

Therapeutic Catheter Procedures in Pediatrics

There is a large spectrum of interventional catheter procedures being performed presently in children. The procedures that offer a greater advantage than surgical techniques and that will continue to be established procedures include percutaneous angioplasty of the pulmonary valve, peripheral pulmonary artery and caval stenosis, embolizations of pulmonary collaterals and pulmonary arteriovenous malformations, angioplasty of vascular access shunt, embolization of bronchial arteries for hemoptysis, and percutaneous nephrostomy and abscess drainage procedures. Others that have been successful but not yet routinely established in children include thrombolysis, renal artery angioplasty, embolization of peripheral arteriovenous malformations, dilatation of the urinary and gastrointestinal tract stenosis, and percutaneous biopsy.

Systemic to pulmonary collaterals mimicking patent ductus arteriosus in neonates with prolonged ventilatory courses

THE PRESENCE o f shunts f rom the sys temic to the p u l m o n a r y ar ter ia l c i rcu la t ion has been well d o c u m e n t e d in p r e m a t u r e infants wi th resp i ra to ry dis t ress syndrome. The mos t c o m m o n site o f shun t ing is a pa t en t duc tus ar ter iosus . These duc ta l shunts are a ignif icant componen t o f resp i ra to ry dis t ress syndrome , and are of ten s i lent . TM A P D A is no t the only cause o f ex t r aca rd iac le f t tor ight shunts in p r e m a t u r e infants , as d e m o n t r a t e d by the fol lowing two cases.

Surgical Correction of Pulmonary Atresia and Ventricular Septal Defect with Large Systemic-Pulmonary Collaterals

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 γ 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 γ graft by using a valved Dacron conduit and the ventricular septal defect was closed.