AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Pulmonary atresia with ventricular septal defect (PA-VSD) is a cyanotic congenital heart disease characterized by underdevelopment of the right ventricular (RV) outflow tract (ie, subpulmonary infundibulum) with atresia of the pulmonary valve, a large ventricular septal defect (VSD), and overriding of the aorta. In the past, this anomaly was termed pseudotruncus or truncus arterious type 4.

PA-VSD demonstrates a wide spectrum of severity, depending on the degree of pulmonary artery development. Pathologically, PA-VSD is frequently considered the most severe end of the spectrum of tetralogy of Fallot (TOF), but controversy exists as to whether PA-VSD and TOF should be treated as 2 distinct entities. In patients with the standard type of TOF with pulmonary atresia, pulmonary arteries are usually normal in size with normal peripheral pulmonary arborization, which is unlike PA-VSD. In addition, systemic-to-pulmonary collateral vessels are not as well developed in patients with TOF with pulmonary atresia as they are in patients with PA-VSD.

Frequency

The best estimates of the relative frequency of PA-VSD are 2.5-3.4% of all congenital cardiac malformations. PA-VSD is slightly more prevalent in males than in females.

Etiology

The actual genetic cause of PA-VSD is unknown. An association with velocardiofacial syndrome and DiGeorge syndrome has been found. Children of patients with PA-VSD have a higher risk of having congenital heart lesions than children of parents without PA-VSD.

Pathophysiology

In PA-VSD, the extent of pulmonary artery development determines the clinical presentation and the surgical options available. Pulmonary artery atresia may be local only, with involvement of the pulmonary valve and the proximal portion of the pulmonary trunk, or it may involve a longer segment. The right and left pulmonary arteries may communicate freely (ie, confluence) or may not communicate (ie, nonconfluence). Pulmonary circulation may be supplied by a patent ductus arteriosus (PDA), systemic-to-pulmonary collaterals, or plexuses of bronchial and pleural arteries.

The pathology of intrapulmonary arteries depends on the pulmonary blood flow and the patency of the ductus. If the ductus is large and supplies confluent pulmonary arteries, the blood flow and the intrapulmonary arteries of both lungs are normal. If collaterals are multiple and the ductus is congenitally absent, abnormal intrapulmonary arborization (ie, stenosis of unbranched and intrapulmonary arteries) and pulmonary hypertension are present.

Collateral arteries most commonly arise from the thoracic aorta and less commonly arise from subclavian arteries, internal mammary arteries, intercostal arteries, or the abdominal aorta. Rarely, the collateral arteries arise from coronary arteries. In 60% of patients, the collateral arteries are stenosed at the aortic end or at intrapulmonary sites, and stenosis tends to progress over time.

The VSD may be membranous or infundibular, is usually very large, and rarely is obstructed by membranous tissue. In 50% of patients, a secundum-type atrial septal defect (ASD) or a patent foramen ovale (PFO) also is present. In 26-50% of patients, the aorta arises predominantly from the RV and a dilated right-sided aortic arch may be present.

The RV and, to a lesser extent, the right atrium usually are moderately to markedly hypertrophied and dilated. The left atrium and left ventricle (LV) usually are normal. The coronary arteries usually are normal, although anomalies have been observed, such as a high origin of the coronary ostia, coronary artery–to–pulmonary artery fistulae, and transposition anatomy with the right coronary artery originating from the left anterior aortic sinus and transversing the right ventricular infundibulum. Other associations include tricuspid atresia or stenosis, complete atrioventricular (AV) canal, complete or corrected transposition of the great arteries, left superior vena cava, anomalies of the coronary sinus, dextrocardia, and asplenia or polysplenia syndrome.

Classification

• Type A: Pulmonary blood flow is provided by native pulmonary arteries.
• Type B: Pulmonary blood flow is supplied by native pulmonary arteries and by major aortopulmonary collateral arteries.
• Type C: Pulmonary blood flow is provided by major aortopulmonary collateral arteries.

Clinical

The age at presentation may vary depending on the amount of pulmonary blood flow. However, the great majority of patients present in the newborn period after the closure of the ductus arteriosus. If collateral vessels are well developed, presentation may be delayed, although rarely.

The vast majority of patients present with cyanosis and hypoxia. Hypoxia usually is severe and is present when the entire pulmonary flow is reduced and a closing ductus arteriosus is the only source of pulmonary blood flow. If systemic collateral arteries are well developed or if the PDA is wide open, hypoxia is not severe in neonates. Patients may present with progressive hypoxia later because growth outstrips the pulmonary blood flow.

On rare occasions, an infant with a large PDA or well-developed systemic collateral arteries may present at age 4-6 weeks with heart failure with increased pulmonary blood flow and minimal cyanosis. This heart failure may be very difficult to control medically. Paroxysms of dyspnea and squatting occasionally occur in older children.

Hemoptysis may occur as a result of rupture of extensive systemic-to-pulmonary collateral arteries. Important and recurrent infections can occur because of immunodeficiency, especially if associated with DiGeorge syndrome. Survival to adulthood has been described in a few patients with well-developed collateral arteries.

Growth and development are usually delayed secondary to cyanosis or congestive heart failure (CHF).

Central (ie, perioral) cyanosis is usually mild at birth, but it becomes very severe with the closure of the PDA. Cyanosis may fluctuate for the first few days because the ductus arteriosus may constrict and relax intermittently. The patient may have anomalies of the face, palate, and ears as described in velocardiofacial syndrome. Peripheral pulses are usually normal in neonates and remain normal in cyanotic infants. In infants with wide-open PDAs, well-developed systemic collateral arteries, or surgically created shunts, pulses may become pronounced after 4-6 weeks because of a wide pulse pressure.

Signs of heart failure are rare. Heart pulsation is most prominent at the left lower sternal border. Heart size is usually normal. A prominent a wave in the jugular pulse may be found. The following may be observed on auscultation:

• S₁ is normal; S₂ (ie, aortic valve closure) is always single and often accentuated. A grade 3/6 systolic murmur usually is audible along the lower left sternal border.
• A continuous murmur is best heard over the upper chest in the presence of a PDA.
• If systemic-to-pulmonary collateral arteries are present, continuous murmurs may be diffusely audible over the entire chest and back.
• In some patients with severe cyanosis, no murmur can be heard.
• An early diastolic murmur of aortic regurgitation may be noted.

Distinguishing characteristics for the diagnosis of PA-VSD can be divided into 2 major groups, as follows:

• Decreased pulmonary blood flow in a neonate with cyanosis
  • Severe tetralogy of Fallot
  • Transposition of the great arteries with pulmonary stenosis
  • Tricuspid atresia
  • A double-outlet RV with severe pulmonary stenosis
  • A single ventricle with severe pulmonary stenosis
  • Total anomalous pulmonary venous connection with pulmonary venous obstruction
• Normal or increased pulmonary blood flow in a neonate with minimal cyanosis with or without heart failure
  • VSD
  • PDA
  • AV canal defect
  • A double-outlet RV without significant pulmonary stenosis
  • A single ventricle without significant pulmonary stenosis
  • Persistent truncus arteriosus
  • Total anomalous pulmonary venous connection without pulmonary venous obstruction

Consult a pediatric cardiologist, a pediatric cardiothoracic surgeon, and a geneticist.

INDICATIONS

Section 3 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Criteria for complete surgical repair are as follows:

• If central pulmonary arteries are present, their central area must be more than 50% of normal for the patient's age and body surface area.
• The pulmonary arteries must supply at least 10 segments, the equivalent of one lung.
• If a single pulmonary artery is present, it must be normal in size and reach all segments of that lung.

CONTRAINDICATIONS

Section 4 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Contraindications for complete surgical repair include (1) hypoplastic or absent central pulmonary arteries and (2) inadequate peripheral arborization of pulmonary arteries.

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Lab Studies

• No laboratory or blood tests are available to confirm pulmonary atresia with ventricular septal defect (PA-VSD).
• Pulse oxymetry can assist the diagnosis of cyanosis, especially in patients with dark skin and anemia (>5 mg/dL of reduced hemoglobin is required).
• An arterial blood gas assessment can reveal hypoxemia and hypocarbia without any significant improvement with hyperoxia, favoring a diagnosis of cyanotic congenital heart disease.
• Reactive polycythemia and coagulation defects may be evident from the results of hematologic studies.
• Because PA-VSD is associated, in some cases, with DiGeorge syndrome and velocardiofacial syndrome, genetic evaluation including a fluorescent in situ hybridization (FISH) test may be required.

Imaging Studies

• Chest radiography
• • A boot-shaped heart (coeur en sabot) is observed. It occurs secondary to an upturned cardiac apex caused by RV hypertrophy and concavity in the region of the main pulmonary artery, which is produced by underdevelopment of the subpulmonary infundibulum.
  • The heart size is usually normal or slightly enlarged, most often with an RV configuration.
  • The main pulmonary arterial shadow normally depicted on chest radiographs is absent.
  • The pulmonary vascular markings have a heterogeneous reticular pattern in the presence of collateral arteries from the systemic arteries.
  • Approximately 50% of patients have a right aortic arch with a large aorta.
  • The lung field is oligemic in patients with very small collateral arteries.
  • Lung fields may be flooded if the patient has a large PDA with normally developed central pulmonary arteries or well-developed systemic collateral arteries.
• Echocardiography
• • Parasternal long-axis scans reveal a large aortic valve overriding a malaligned VSD.
  • Position of malalignment of the VSD (membranous or infundibular) and a blind hypoplastic RV infundibulum is easily observed using parasternal cross-sectional echocardiography.
  • ASDs and other muscular VSDs can be detected.
  • Scans from the suprasternal notch and high parasternal windows usually can provide important information regarding the size of the proximal pulmonary arteries and the presence of confluence. These views also can help define the side of the aortic arch and assess the patency of the ductus arteriosus.
  • A right-sided aortic arch is frequently defined using the suprasternal notch view.
  • Defining all the collateral arteries with echocardiography is difficult.
  • Short-axis parasternal and subcostal views are used to detect coronary artery abnormalities.
• Magnetic resonance imaging: MRI is a less invasive technique used to help define the surgically relevant pulmonary artery anatomy, but MRI images are inadequate for defining peripheral pulmonary arterial distribution.

Other Tests

• Electrocardiography
• • RV hypertrophy and right-axis deviation are the rule.
  • Right atrial hypertrophy also is present.
  • In a small subgroup of patients with increased pulmonary blood flow, combined ventricular hypertrophy with left atrial enlargement may be present.

Diagnostic Procedures

• Cardiac catheterization and angiography help delineate the size and distribution of the true pulmonary arteries and the collateral arteries.
• • Right atrial pressure is normal unless tricuspid incompetence is present.
  • Pressures in the RVs are at a systemic level because of the nonrestricted VSD.
  • The pulmonary artery cannot be manipulated through the right side.
  • Aortic pulse pressure is normal or wide, depending on the presence of a large PDA or collateral arteries.
  • True pulmonary arterial resistance is normal.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Medical therapy

In patients with a ductal-dependent circulation, prostaglandin E₂ is often required to keep the ductus arteriosus open in the early neonatal period until surgery can be performed.

A neonate who is ill may require fluid and acidosis management, but mechanical ventilation is rarely needed.

Medical treatment with digitalis, diuretics, and other agents may be indicated in patients with CHF resulting from increased pulmonary blood flow. Phlebotomy to relieve the adverse effects of extreme polycythemia in very hypoxic patients is rarely performed.

In patients with CHF and increased work of breathing, a high-energy diet is required. Rarely, a patient may require placement of a nasogastric tube to achieve the goals of energy intake.

Surgical therapy

Various options are available, depending on the anatomy of the individual patient.

Palliative surgery

If the atresia is limited to the pulmonary valve (eg, imperforate pulmonary valve, membranous pulmonary atresia), the valve can be perforated percutaneously using special devices designed for this specific purpose, such as a needle or, more recently, a radiofrequency ablation catheter. Then, after the perforation is done, the valve is dilated with a balloon catheter. Stents can be placed in stenosed aortopulmonary collateral arteries in patients with hypoplastic pulmonary arteries.

Palliative extracardiac systemic-to-pulmonary shunts can be placed to promote growth of pulmonary arteries. Direct aortopulmonary shunts (eg, Waterston shunt, Pott shunt) were used in the past but, subsequently, were found to create severe distortion, scarring, interruption of the pulmonary arteries, and, on occasion, pulmonary hypertension. Thus, the use of these shunts has fallen into disfavor. Currently, the modified Blalock-Taussig shunt is used most commonly and is connected from the subclavian or innominate artery to the pulmonary artery (when anatomy permits). In recent years, a direct right ventricle to pulmonary arteries shunt has been placed with good results.

Valveless conduits or homografts may be used to connect the RV to the pulmonary artery. This may promote the growth of pulmonary arteries.

In infants with CHF caused by excessive aortopulmonary collateral arteries, flow can be reduced by performing surgical interruption or by judicious banding or percutaneous coil occlusion of selected systemic arterial collaterals.

Complete surgical repair

The objective of complete repair is to create an unrestricted continuity between the RV outflow tract and the pulmonary arterial tree using nonvalved or valved conduits. Subsequently, all extracardiac sources of pulmonary blood flow need to be ligated. The ASDs and VSDs need to be closed. An important goal is to achieve a satisfactory ratio between the peak systolic pressures in the RV and the LV (RV/LV ratio).

Various approaches have been devised to achieve a complete surgical repair, including the following:

• If a patient meets all the criteria for complete repair, single-stage unifocalization of pulmonary blood supply and complete intracardiac repair is the procedure of choice.
• Single-stage unifocalization and postponement of VSD closure to a second operation is an option.
• Sequential unilateral unifocalization followed by intracardiac repair is preferred in some patients.

Heart-lung transplantation

In patients with completely atretic main, left, and right pulmonary arteries, heart-lung transplantation is a viable option.

Complications of surgery include the following:

• In the unifocalization procedure, severe airflow limitation occurs after the unifocalization surgery because of tracheobronchial epithelial ischemia resulting from interruption of the tracheobronchial blood supply. This complication significantly contributes to early postoperative morbidity and mortality rates.
• Aortic regurgitation or aortic root dilation may occur.
• Restenoses of the shunts and neopulmonary arteries may occur, and subsequent interventions may be required.

Follow-up

Careful monitoring for drug dosing and adverse effects is necessary. Monitor patients for adequacy of repair and postoperative complications. Obtain echocardiograms on a regular basis, paying special attention to surgically created shunts, residual shunts, and the flow through RV outflow tract conduits.

For excellent patient education resources, visit eMedicine's Heart Center. Also, see eMedicine's patient education articles Tetralogy of Fallot and Ventricular Septal Defect.

COMPLICATIONS

Section 7 of 10  

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• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Possible complications include the following:

• Congestive heart failure
• Erythrocytosis
• Infective endocarditis
• Brain abscess
• Delayed growth and puberty
• Arrhythmias and sudden death

OUTCOME AND PROGNOSIS

Section 8 of 10  

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• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Patients may require repeated surgeries for a complete repair. Educate family members regarding congenital heart disease and how to perform cardiopulmonary resuscitation (CPR). Genetic counseling for future pregnancies is necessary.

MULTIMEDIA

Section 9 of 10  

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

Media file 1:  Left ventricular angiography (right anterior oblique caudal view) in a patient with pulmonary atresia with ventricular septal defect (PA-VSD). The catheter has been advanced from the inferior vena cava to the right atrium, across the atrial septal defect to the left atrium, and then to the left ventricle. The left ventricle fills with contrast and has good systolic function. Left-to-right shunting of contrast is present across a ventricular septal defect; however, no blood is flowing out the right ventricle. A blind pouch is observed in the area of the right ventricular outflow tract. All of the contrast medium (flow) exits the heart via the aorta. The pulmonary circulation is supplied by collateral vessels arising from the descending aorta. See Images 2-3 for still frames.
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Media type:  Video

Media file 2:  Angiography. Left anterior oblique ventriculogram in a patient with pulmonary atresia with ventricular septal defect (PA-VSD) (same patient as Images 1-3). The angiogram shows the left and right ventricles with a large malalignment ventricular septal defect between them. The only outflow from the heart is the aorta. No evidence of pulmonary blood flow is observed arising from the ventricles directly to the lungs. LV=left ventricle; RV=right ventricle; Asc Ao=ascending aorta; Desc Ao=descending aorta.
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Media type:  Image

Media file 3:  Angiography. Anteroposterior view of an aortogram in a patient with pulmonary atresia with ventricular septal defect (PA-VSD) (same patient as Images 1-2). The pulmonary circulation is supplied by collateral vessels (Collaterals) that arise from the descending aorta. Desc Ao=descending aorta.
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Media type:  Image

Media file 4:  Echocardiography. Short-axis parasternal view in a patient with pulmonary atresia with ventricular septal defect (PA-VSD). Note the trileaflet aortic valve in the center of the picture. The tricuspid valve is on the left (9- to 10-o'clock position). The normal pulmonary valve position is on the right (2- to 3-o'clock position). This echocardiogram demonstrates that the pulmonary valve is atretic. See Image 5 for a still frame.
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Media type:  Video

Media file 5:  Echocardiograms and diagrams. Short-axis parasternal view (1) and diagram (3) in a patient with pulmonary atresia and ventricular septal defect (PA-VSD). Short-axis parasternal view (2) and diagram (4) in a patient with normal anatomy. RA=right atrium; LA=left atrium; RV=right ventricle; PA=pulmonary artery; TR=tricuspid valve; PV=pulmonary valve.
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Media type:  Image

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Indications
• Contraindications
• Workup
• Treatment
• Complications
• Outcome and Prognosis
• Multimedia
• References

• Beauchesne LM, Warnes CA, Connolly HM, et al. Prevalence and clinical manifestations of 22q11.2 microdeletion in adults with selected conotruncal anomalies. J Am Coll Cardiol. Feb 15 2005;45(4):595-8. [Medline].
• Bharati S, Paul MH, Idriss FS, et al. The surgical anatomy of pulmonary atresia with ventricular septal defect: pseudotruncus. J Thorac Cardiovasc Surg. May 1975;69(5):713-21. [Medline].
• Black MD, Shukla V, Freedom RM. Direct neonatal ventriculo-arterial connections (REV): early results and future implications. Ann Thorac Surg. Apr 1999;67(4):1137-41. [Medline].
• Dodds GA 3rd, Warnes CA, Danielson GK. Aortic valve replacement after repair of pulmonary atresia and ventricular septal defect or tetralogy of Fallot. J Thorac Cardiovasc Surg. Apr 1997;113(4):736-41. [Medline].
• El-Said HG, Clapp S, Fagan TE, et al. Stenting of stenosed aortopulmonary collaterals and shunts for palliation of pulmonary atresia/ventricular septal defect. Catheter Cardiovasc Interv. Apr 2000;49(4):430-6. [Medline].
• Fiane AE, Lindberg HL, Seem E, Geiran OR. Homografts for right ventricular outflow tract reconstruction in congenital heart disease. Scand Cardiovasc J. 1997;31(6):351-6. [Medline].
• Gill CC, Moodie DS, McGoon DC. Staged surgical management of pulmonary atresia with diminutive pulmonary arteries. J Thorac Cardiovasc Surg. Mar 1977;73(3):436-42. [Medline].
• Hausdorf G, Schneider M, Schulze-Neick I, Lange PE. [Pulmonary valve atresia with ventricular septum defect: interventional recanalization of the right ventricular outflow tract]. Z Kardiol. Sep 1992;81(9):496-9. [Medline].
• Horer J, Friebe J, Schreiber C, et al. Correction of tetralogy of Fallot and of pulmonary atresia with ventricular septal defect in adults. Ann Thorac Surg. Dec 2005;80(6):2285-91. [Medline].
• Huhta JC, Piehler JM, Tajik AJ, et al. Two dimensional echocardiographic detection and measurement of the right pulmonary artery in pulmonary atresia-ventricular septal defect: angiographic and surgical correlation. Am J Cardiol. Apr 1 1982;49(5):1235-40. [Medline].
• Jedele KB, Michels VV, Puga FJ, Feldt RH. Velo-cardio-facial syndrome associated with ventricular septal defect, pulmonary atresia, and hypoplastic pulmonary arteries. Pediatrics. May 1992;89(5 Pt 1):915-9. [Medline].
• Julsrud PR. Magnetic resonance imaging of the pulmonary arteries and veins. Semin Ultrasound CT MR. Jun 1990;11(3):184-205. [Medline].
• Mair DD, Julsrud PR. Diagnostic evaluation of pulmonary atresia and ventricular septal defect: Cardiac catheterization and angiography. Prog Pediatr Cardiol. 1992;1(1):23-36.
• Mohammadi S, Belli E, Martinovic I, et al. Surgery for right ventricle to pulmonary artery conduit obstruction: risk factors for further reoperation. Eur J Cardiothorac Surg. Aug 2005;28(2):217-22. [Medline].
• Puga FJ. Surgical treatment of pulmonary atresia and ventricular septal defect. Prog Pediatr Cardiol. 1992;1(1):37-49.
• Rabinovitch M, Herrera-deLeon V, Castaneda AR, Reid L. Growth and development of the pulmonary vascular bed in patients with tetralogy of Fallot with or without pulmonary atresia. Circulation. Dec 1981;64(6):1234-49. [Medline].
• Reddy VM, McElhinney DB, Amin Z, et al. Early and intermediate outcomes after repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries: experience with 85 patients. Circulation. Apr 18 2000;101(15):1826-32. [Medline].
• Reichenspurner H, Netz H, Uberfuhr P, et al. Heart-lung transplantation in a patient with pulmonary atresia and ventricular septal defect. Ann Thorac Surg. Jan 1994;57(1):210-2. [Medline].
• Schulze-Neick I, Ho SY, Bush A, et al. Severe airflow limitation after the unifocalization procedure: clinical and morphological correlates. Circulation. Nov 7 2000;102(19 Suppl 3):III142-7. [Medline].
• Tchervenkov CI, Roy N. Congenital Heart Surgery Nomenclature and Database Project: pulmonary atresia--ventricular septal defect. Ann Thorac Surg. Apr 2000;69(4 Suppl):S97-105. [Medline].
• Tchervenkov CI, Salasidis G, Cecere R, et al. One-stage midline unifocalization and complete repair in infancy versus multiple-stage unifocalization followed by repair for complex heart disease with major aortopulmonary collaterals. J Thorac Cardiovasc Surg. Nov 1997;114(5):727-35; discussion 735-7. [Medline].
• d'Udekem Y, Alphonso N, Norgaard MA, et al. Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries: unifocalization brings no long-term benefits. J Thorac Cardiovasc Surg. Dec 2005;130(6):1496-502. [Medline].

Article Last Updated: May 17, 2006