eMedicine Specialties > Pediatrics: Cardiac Disease and Critical Care Medicine > Cardiology

Atrioventricular Septal Defect, Complete

Author: Michael McConnell, MD, Department of Pediatrics, Division of Cardiology, Clinical Associate Professor of Pediatrics, Clinical Assistant Professor, Children's Healthcare of Atlanta and Emory University
Coauthor(s): John Scheitler, MD, Consulting Staff, Piedmont Adult and Pediatric Medicine Associates, PA
Contributor Information and Disclosures

Updated: Oct 3, 2007

Introduction

Background

The terms endocardial cushion defect (ECD), atrioventricular (AV) septal defect (AVSD), and common AV canal (CAVC) defect are interchangeable in describing defects in the formation of the AV valves, the anterior portion of the atrial septum, and the posterior portion of the ventricular septum. Endocardial cushions are masses of mesenchymal tissue that form components of the AV valves, atrial septum, and ventricular septum.

Defects range from incomplete, which is also called partial (eg, ostium primum atrial septal defect with cleft mitral valve), to transitional (eg, large ostium primum defect and small inlet or posterior ventricular septal defect [VSD]) to complete (eg, large ostium primum atrial septal defect, large-inlet VSD, common AV valve). Depending on the size of the ventricular septal communication and the competence of the AV valve or AV valves, patients with AV canal (AVC) defects may become symptomatic early in life or may remain relatively asymptomatic until young adulthood. This article focuses on the most severe end of the spectrum, or the CAVC defect.

Abnormal proliferation or migration of the 4 endocardial cushions (ie, superior, inferior, right lateral, left lateral) is thought to cause the defect during embryologic development. Lateral cushions may normally contribute to the posterior mitral-valve leaflet and the posterior (diaphragmatic) tricuspid valve leaflet. The complete form of CAVC is characterized by a lack of fusion between the superior and inferior cushions, leading to a cleft appearance in the anterior mitral leaflet and in the anterior and septal tricuspid leaflets and also preventing complete septation of the atria and ventricles.

The most common arrangement of valve leaflets (Rastelli type A) includes abnormal superior (anterior) and inferior (posterior) bridging leaflets that cross the atrial and VSDs. The superior bridging leaflet is attached at its leftmost extent to the anteromedial papillary muscle of the left ventricle (LV) and at its rightmost extent to the papillary muscle of the conus in the right ventricle (RV). A left lateral leaflet is found in the LV, and 2 more leaflets, a right superior and right lateral, are found in the RV (see Media file 1).

In the alignment of the common AV valve vis-à-vis the septum primum is such that each atrium is situated over approximately 50% of the common AV orifice. The alignment of the common AV valve vis-à-vis the trabecular ventricular septum results in approximately 50% of the common AV orifice being situated over each ventricle (ie, balanced form).

Pathophysiology

The pathophysiology of the complete form of CAVC depends on the magnitude of blood flow through the VSD and the amount of AV-valve regurgitation. Patients with little AV-valve regurgitation and high pulmonary vascular resistance (PVR) are asymptomatic early in life, and their condition may be difficult to diagnose. These patients occasionally remain relatively asymptomatic until their second or third decade, when they develop increasing cyanosis from advanced pulmonary vascular disease. If the PVR decreases normally in the first 6 weeks of life, patients develop a large left-to-right shunt through both the atrial and ventricular defects, resulting in congestive heart failure (CHF). Patients with clinically significant AV-valve regurgitation may also have signs of CHF, such as tachypnea, excessive sweating, and failure to appropriately gain weight.

Frequency

United States

AVC defects are relatively common. Fetal echocardiographers report that 17% of children with cardiac defects identified in utero have some form of AVC defect. The occurrence of any form of AVC defect is estimated to be 0.19 case per 1000 live births. The complete form of CAVC is more common than the incomplete (partial) or transitional forms.

Freeman et al (1998) reported a prevalence of 9.6 cases of Down syndrome per 10,000 live births.1 Congenital heart disease is present in 44% of affected infants, and AVC defects are present in 45% of infants with Down syndrome and congenital heart disease.

Familial clustering may occur with AVC defects. About 14% of women with CAVC pass on congenital heart disease to their children. This rate is higher than that reported for other defects and typically manifests as complete CAVC or tetralogy of Fallot (TOF). In a pedigree analysis, 11.7% of probands had a family history of congenital heart disease. When related to a syndrome such as Down syndrome, AVC defects are usually of the complete type.

As with many forms of congenital heart disease, the complete form of AVC appears to have a multifactorial inheritance pattern. Mutation of the CRELD1 gene increases the risk that the offspring will have an AVSD. However, by itself, this mutation is not sufficient to cause the defect; this observation indicates that AVSD is multigenic.

Mortality/Morbidity

Patients with the complete form of CAVC typically develop tachypnea and failure to thrive in the first few months of life. Tachypnea hampers normal feeding. In addition, respiratory tract infections, such as those due to respiratory syncytial virus (RSV), are poorly tolerated.

Patients may survive past the first few years of life without surgical intervention if the PVR remains elevated, though they may develop irreversible pulmonary vascular obstructive disease (PVOD) at a rapid rate. Surgical morbidity and mortality rates associated with this defect have dramatically improved over the years. Some centers report a surgical survival rate of 94% and an overall survival rate of 91% in patients with the balanced form of complete CAVC repaired by 4-6 months of age. About 3% of patients with a surgical heart block require a pacemaker, and about 7% may require repeat operation for residual defects or surgically induced mitral insufficiency. Actuarial survival at 13 years is 81%.

  • In patients with a nonrestrictive VSD component, pulmonary vascular disease (Eisenmenger syndrome) eventually occurs unless the VSD component is surgically closed. Rare cases have occurred even when surgical repair is successfully accomplished in infants younger than 6 months. Cyanosis occurs when patients develop some degree of right-to-left shunt at either atrial or ventricular levels. Although patients' quality of life may be impaired at this point, their life expectancy may be 20-50 years.
  • In most patients with CAVC, the common AV valve is equally shared between the ventricles. However, in some cases, the common AV valve is not equally shared; in a subset of these unbalanced cases, the LV may be too small to support the systemic arterial circulation. In this situation, the surgical risk is increased, and septation of the heart into 2 independent ventricles may not be possible. Converting the patient's anatomy to single-ventricle circulation, in which all of the systemic venous blood is directed to the lungs with a Fontan operation, may be necessary. Long-term morbidity and mortality rates for patients receiving a palliative Fontan operation are worse than those of patients with 2-ventricle circulation.
  • Treatment for the complete form of AVC is primarily surgical. Operative morbidity and mortality for this procedure has dramatically improved over the past 20 years. Tweddell et al (1996) identified risk factors for surgical and late mortality and morbidity; these are the era of operation, patient's age at operation, severity of left AV-valve regurgitation, magnitude of preoperative heart failure, presence of accessory AV-valve orifices, other congenital heart disease, and Down syndrome.2
  • In infants, the published mortality rate for CAVC repair is 3.6% with minimal long-term morbidity; the 10-year survival rate is 81%. Bando et al (1995) found similar results while identifying risk factors for early death and the need for repeat operation.3 Risk factors included postoperative pulmonary hypertensive crisis, immediate postoperative severe left AV-valve regurgitation, and a double-orifice left AV valve. McElhinney et al (1998) describe an occasional anomalous attachment or tissue of the AV valve, which may complicate operative repair.4

Race

The occurrence does not appear to vary on the basis of race. Advanced maternal age is a risk factor for Down syndrome, and because at least two thirds of patients with the uncomplicated complete form of AVC have trisomy 21, ethnic groups in which advanced maternal age is common may have an increased incidence of the complete form of AVC.

Sex

The male-to-female ratio for the complete form of AVC is 1:1.

Age

Patients with the complete form of CAVC often present with symptoms early in life. CHF usually develops by 6 weeks as PVR decreases and pulmonary blood flow increases. A rare case of survival to the eighth decade with untreated complete CAVC was reported. In some patients, PVR never decreases, and symptoms of CHF do not develop. In these rare cases, patients may remain asymptomatic as their pulmonary vascular obstructive changes worsen until cyanosis develops because of a right-to-left shunt.

Clinical

History

Tachypnea, repeated respiratory infections, poor feeding, and failure to thrive are frequent symptoms in patients with the complete form of AVC and large left-to-right shunts. These symptoms are usually present by 6-8 weeks and due to blood flow through the large interventricular communication with or without incompetence of the common AV valve. Pulmonary vascular disease results from damage caused by excessive pulmonary flow and elevated pulmonary artery pressure due to the large VSD. Irreversible pulmonary vascular disease may be present by age 2 years or, in rare cases, earlier.

Physical

  • General physical examination may show signs of Down syndrome (Brushfield spots, simian crease, epicanthal folds, clinodactyly). Inspection may show pallor or Harrison grooves (horizontal depression along lower border of chest at diaphragm insertion site due to chronic tachypnea). Failure to thrive because of excessive metabolic cardiovascular requirements and poor caloric intake due to tachypnea is common.
  • Cardiovascular examination may reveal a prominent and active precordium because of volume and pressure overload. Small arterial pulsations are often present. A holosystolic AV-valve regurgitation murmur may obscure the closure sound of the common AV valve (first heart sound [S1]). Because of the large VSD, pulmonary arterial pressure is elevated, resulting in a single loud second heart sound (S2). A systolic flow–type crescendo-decrescendo murmur caused by excessive blood flow across the pulmonary outflow tract may also be audible. If the patient has a large left-to-right shunt, a low-frequency diastolic sound caused by a large amount of blood crossing the AV valve in diastole is heard at the lower left sternal border.
    • When PVR is elevated, the systolic murmur may not be prominent, and the diastolic rumble may disappear, reflecting less left-to-right shunt. This finding can occur in the infant in whom PVR has never fallen or in the older child with developing PVOD, for whom the improvement in CHF symptoms is an ominous finding.
    • With advanced PVOD, the left parasternal impulse is prominent, S2 may be palpable, and the systolic murmur may be soft and short. A high-pitched decrescendo diastolic murmur of pulmonary insufficiency (Graham Steell murmur) may be detected at the left upper sternal border, reflecting severely elevated PVR.
  • Factors that can influence hemodynamics in Down syndrome include chronic nasopharyngeal obstruction, relative hypoventilation, carbon dioxide retention, and sleep apnea. Nonspecific CHF signs that may be seen include hepatosplenomegaly, pulmonary rales, and tachypnea. Skull erosion and striations have been noted from venous distension and increased blood volume.

Causes

  • Retinoic acid pathways have been implicated as a possible cause of AVC defects. When one form of retinoic acid is applied to the avian embryo during the primitive streak stage, formation of AV cushions is disturbed. Absence of the RXR-alpha gene can predispose to ECDs. Decreased growth of RV myocardium and increased growth of AV cushions change the hemodynamics and resultant cardiac development. The homozygous null FOG2 mouse has the complete form of AVC severely malaligned toward the LV. Low birth weight for gestational age may be causally related to ECDs, even after the data are adjusted for other maternal, gestational, and infant factors.
  • Trisomy 21 (Down syndrome) is the most frequently associated genetic abnormality with common AV canal (CAVC), although it may also occur in association with trisomy 13 and trisomy 18. In patients without trisomy 21 who have CAVC defects, a genetic locus on chromosome 1 can account for the disorder in some families.
  • Interstitial deletion on chromosome 16 can be associated with ECDs. Endocardial cushion tissue seems to function as an adhesive for myocardial structures. Fibroblasts of endocardial cushions in trisomy 21 tend to be more adhesive, possibly leading to cardiac malformations. ECDs may be seen with other less common syndromes, such as Dandy-Walker malformation, Joubert syndrome, and Ritscher-Schintal (craniocerebellocardiac) syndrome. An orocardiodigital syndrome consisting of tongue hamartomas, polysyndactyly, and CAVC has been described.
  • CAVC defect is one of several cardiac abnormalities commonly seen with heterotaxy syndromes (asplenia and occasionally with polysplenia). Other rare combinations include CAVC with total anomalous pulmonary venous return and CAVC with Ebstein anomaly. Uncommon associations with CAVC are DiGeorge syndrome and coloboma of the eye, heart defects, atresia of the choanae, renal anomalies and retardation of growth and/or development, genital anomalies in males such as micropenis or cryptorchidism, and ear abnormalities or deafness (CHARGE) syndrome.
  • Recently, the presence of vascular endothelial growth factor (VEGF) gene mutations has been associated with endocardial cushion defects.5  The prevalence of the VEGF +405C allele was higher in patients with CHD than in control subjects (0.42 vs 0.21, P <.05). The presence of VEGF +405C presented increased risk for CHD (odds ratio [OR], 1.72, 95% CI 1.32–2.26).
  • Familial clustering may occur with AVC defects. As with many forms of congenital heart disease, the complete form of AVC appears to have a multifactorial inheritance pattern.
  • Advanced maternal age is a risk factor for Down syndrome, and at least two thirds of patients with the uncomplicated complete form of AVC have trisomy 21.

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References

  1. Freeman SB, Taft LF, Dooley KJ, et al. Population-based study of congenital heart defects in Down syndrome. Am J Med Genet. Nov 16 1998;80(3):213-7. [Medline].

  2. Tweddell JS, Litwin SB, Berger S, et al. Twenty-year experience with repair of complete atrioventricular septal defects. Ann Thorac Surg. Aug 1996;62(2):419-24. [Medline].

  3. Bando K, Turrentine MW, Sun K, et al. Surgical management of complete atrioventricular septal defects. A twenty-year experience. J Thorac Cardiovasc Surg. Nov 1995;110(5):1543-52; discussion 1552-4. [Medline].

  4. McElhinney DB, Reddy VM, Silverman NH, Hanley FL. Accessory and anomalous atrioventricular valvar tissue causing outflow tract obstruction: surgical implications of a heterogeneous and complex problem. J Am Coll Cardiol. Nov 15 1998;32(6):1741-8. [Medline].

  5. Vannay A, Vasarhelyi B, Kornyei M, et al. Single-nucleotide polymorphisms of VEGF gene are associated with risk of congenital valvuloseptal heart defects. Am Heart J. Apr 2006;151(4):878-81. [Medline]. [Full Text].

  6. Najm HK, Coles JG, Endo M, et al. Complete atrioventricular septal defects: results of repair, risk factors, and freedom from reoperation. Circulation. Nov 4 1997;96(9 Suppl):II-311-5. [Medline].

  7. Ten Harkel AD, Cromme-Dijkhuis AH, Heinerman BC, et al. Development of left atrioventricular valve regurgitation after correction of atrioventricular septal defect. Ann Thorac Surg. Feb 2005;79(2):607-12. [Medline].

  8. De Oliveira NC, Sittiwangkul R, McCrindle BW, et al. Biventricular repair in children with atrioventricular septal defects and a small right ventricle: anatomic and surgical considerations. J Thorac Cardiovasc Surg. Aug 2005;130(2):250-7. [Medline].

  9. Buchhorn R, Hulpke-Wette M, Ruschewski W, et al. Effects of therapeutic beta blockade on myocardial function and cardiac remodelling in congenital cardiac disease. Cardiol Young. Feb 2003;13(1):36-43. [Medline].

  10. Wilson W, Taubert KA, Gewitz M, et al. Prevention of Infective Endocarditis. Guidelines From the American Heart Association. A Guideline From the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and the Council on Clinical Cardiology, Council on Cardiovascular Surgery and Anesthesia, and the Quality of Care and Outcomes Research Interdisciplinary Working Group. Circulation. Apr 19 2007;[Medline].

  11. Abbattista AD, Marino B, Iorio FS, Marcelletti C. Complete atrioventricular canal and total anomalous pulmonary venous drainage: a rare association. J Thorac Cardiovasc Surg. Jun 1994;107(6):1536-8. [Medline].

  12. Alexi-Meskishvili V, Ishino K, Dahnert I, et al. Correction of complete atrioventricular septal defects with the double-patch technique and cleft closure. Ann Thorac Surg. Aug 1996;62(2):519-24; discussion 524-5. [Medline].

  13. Allen HD, Emmanouilides GC, Riemenschneider TA, Gutgesell HP. Clinical Synopsis of Moss and Adams' Heart Disease in Infants, Children, and Adolescents. 5th ed. Baltimore, MD: Lippincott, Williams & Wilkins; 1998:253-64.

  14. Backer CL, Mavroudis C, Alboliras ET, Zales VR. Repair of complete atrioventricular canal defects: results with the two- patch technique. Ann Thorac Surg. Sep 1995;60(3):530-7. [Medline].

  15. Bouman HG, Broekhuizen LA, Baasten AM, et al. Stereological study of stage 34 chicken hearts with looping disturbances after retinoic acid treatment: disturbed growth of myocardium and atrioventricular cushion tissue. Anat Rec. Jun 1997;248(2):242-50. [Medline].

  16. Bourdeau A, Dumont DJ, Letarte M. A murine model of hereditary hemorrhagic telangiectasia. J Clin Invest. Nov 1999;104(10):1343-51. [Medline]. [Full Text].

  17. Bove EL, Kavey RE, Sondheimer HM, Parker FB Jr. Subacute bacterial endocarditis and complete endocardial cushion defect. Ann Thorac Surg. Oct 1982;34(4):466-70. [Medline].

  18. Browdie DA, Norberg W, Devig P, et al. Surgical management in interrupted aortic arch and atrioventricular canal. J Thorac Cardiovasc Surg. Nov 1984;88(5 Pt 1):764-9. [Medline].

  19. Cabrera A, Pastor E, Galdeano JM, et al. Cross-sectional echocardiography in the diagnosis of atrioventricular septal defect. Int J Cardiol. Jul 1990;28(1):19-23. [Medline].

  20. Capouya ER, Laks H, Drinkwater DC Jr, et al. Management of the left atrioventricular valve in the repair of complete atrioventricular septal defects. J Thorac Cardiovasc Surg. Jul 1992;104(1):196-201; discussion 201-3. [Medline].

  21. Cherian KM, Pannu HS, Sankar NM, et al. Thoracotomy approach for congenital and acquired heart defects: its possible applications in the current era. J Card Surg. Jan-Feb 1996;11(1):37-45. [Medline].

  22. Chin AJ, Bierman FZ, Sanders SP, et al. Subxyphoid 2-dimensional echocardiographic identification of left ventricular papillary muscle anomalies in complete common atrioventricular canal. Am J Cardiol. Jun 1983;51(10):1695-9. [Medline].

  23. Christoffels VM, Keijser AG, Houweling AC, et al. Patterning the embryonic heart: identification of five mouse Iroquois homeobox genes in the developing heart. Dev Biol. Aug 15 2000;224(2):263-74. [Medline].

  24. Cousineua AJ, Lauer RM, Pierpont ME, et al. Linkage analysis of autosomal dominant atrioventricular canal defects: exclusion of chromosome 21. Human Genetics. 1994;93(2):103-8. [Medline].

  25. DeLeon SY, Ilbawi MN, Wilson WR Jr, et al. Surgical options in subaortic stenosis associated with endocardial cushion defects. Ann Thorac Surg. Nov 1991;52(5):1076-82; discussion 1082-3. [Medline].

  26. Digilio MC, Marino B, Cicini MP, et al. Risk of congenital heart defects in relatives of patients with atrioventricular canal. Am J Dis Child. Dec 1993;147(12):1295-7. [Medline].

  27. Digilio MC, Marino B, Giannotti A, Dallapiccola B. Orocardiodigital syndrome: an oral-facial-digital type II variant associatedwith atrioventricular canal. J Med Genet. May 1996;33(5):416-8. [Medline].

  28. Eisenberg LM, Markwald RR. Molecular regulation of atrioventricular valvuloseptal morphogenesis. Circ Res. Jul 1995;77(1):1-6. [Medline].

  29. Formigari R, Di Donato RM, Gargiulo G, et al. Better surgical prognosis for patients with complete atrioventricular septal defect and Down's syndrome. Ann Thorac Surg. Aug 2004;78(2):666-72; discussion 672. [Medline].

  30. Gembruch U, Knopfle G, Chatterjee et al. Prenatal diagnosis of atrioventricular canal malformations with up-to-date echocardiographic technology: report of 14 cases. Am Heart J. May 1991;121(5):1489-97. [Medline].

  31. Gessner IH, Victorica BE. Pediatric Cardiology: A Problem Oriented Approach. Philadelphia, PA: WB Saunders; 1993:260-1.

  32. Green CE. Plain chest radiography of congenital heart disease in adults. Cardiol Clin. Nov 1983;1(4):685-709. [Medline].

  33. Gruber PJ, Kubalak SW, Pexieder T, et al. RXR alpha deficiency confers genetic susceptibility for aortic sac, conotruncal, atrioventricular cushion, and ventricular muscle defects in mice. J Clin Invest. Sep 15 1996;98(6):1332-43. [Medline].

  34. Hanley FL, Fenton KN, Jonas RA, et al. Surgical repair of complete atrioventricular canal defects in infancy. Twenty-year trends. J Thorac Cardiovasc Surg. Sep 1993;106(3):387-94; discussion 394-7. [Medline].

  35. Hegde HR, Tyrrell MJ, Wilson DR, Leung AK. Skull erosion and bony changes in a child with endocardial cushion defect. Clin Pediatr (Phila). Jan 1988;27(1):46-50. [Medline].

  36. Hoffmeister HE, Apitz J, Fischbach H, Hoffmeister HM. [Hemodynamics and histology of lung blood vessels in 191 patients with atrioventricular canal]. Klin Padiatr. Mar-Apr 1988;200(2):96-101. [Medline].

  37. Jacobstein MD, Fletcher BD, Goldstein S, Riemenschneider TA. Evaluation of atrioventricular septal defect by magnetic resonance imaging. Am J Cardiol. Apr 15 1985;55(9):1158-61. [Medline].

  38. Kosaki K, Curry CJ, Roeder E, Jones KL. Ritscher-Schinzel (3C) syndrome: documentation of the phenotype. Am J Med Genet. Feb 11 1997;68(4):421-7. [Medline].

  39. Kumar N, Prabhakar G, Wilson N, et al. Total correction of transposition of great arteries with atrioventricular septal defect. Ann Thorac Surg. Nov 1992;54(5):989-90. [Medline].

  40. Kurnit DM, Aldridge JF, Matsuoka R, Matthysse S. Increased adhesiveness of trisomy 21 cells and atrioventricular canal malformations in Down syndrome: a stochastic model. Am J Med Genet. Feb 1985;20(2):385-99. [Medline].

  41. Lange A, Mankad P, Walayat M, et al. Transthoracic three-dimensional echocardiography in the preoperative assessment of atrioventricular septal defect morphology. Am J Cardiol. Mar 1 2000;85(5):630-5. [Medline].

  42. LeBlanc JG, Williams WG, Freedom RM, Trusler GA. Results of total correction in complete atrioventricular septal defects with congenital or surgically induced right ventricular outflow tract obstruction. Ann Thorac Surg. Apr 1986;41(4):387-91. [Medline].

  43. Leversha AM, Wilson NJ, Clarkson PM, et al. Efficacy and dosage of enalapril in congenital and acquired heart disease. Arch Dis Child. Jan 1994;70(1):35-9. [Medline].

  44. Lin CC, Lowry RB, Snyder FF. Interstitial deletion for a region in the long arm of chromosome 16. Hum Genet. 1983;65(2):134-8. [Medline].

  45. Marino B, Marcelletti C, Giannotti A, Dallapiccola B. Di George anomaly with atrioventricular canal. Chest. Jan 1991;99(1):242-3. [Medline].

  46. Maslen CL. Molecular genetics of atrioventricular septal defects. Curr Opin Cardiol. May 2004;19(3):205-10. [Medline].

  47. Miyamura H, Eguchi S, Watanabe H, et al. Total circular annuloplasty with absorbable suture for the repair of left atrioventricular valve regurgitation in atrioventricular septal defect. J Thorac Cardiovasc Surg. Jun 1994;107(6):1428-31. [Medline].

  48. Monro JL, Alexiou C, Salmon AP, Keeton BR. Reoperations and survival after primary repair of congenital heart defectsin children. J Thorac Cardiovasc Surg. Aug 2003;126(2):511-20. [Medline].

  49. Perloff JK. The Clinical Recognition of Congenital Heart Disease. Philadelphia, PA: WB Saunders; 1987:322-38.

  50. Reeder GS, Danielson GK, Seward JB, et al. Fixed subaortic stenosis in atrioventricular canal defect: a Doppler echocardiographic study. J Am Coll Cardiol. Aug 1992;20(2):386-94. [Medline].

  51. Rizzoli G, Mazzucco A, Maizza F, et al. Does Down syndrome affect prognosis of surgically managed atrioventricular canal defects?. J Thorac Cardiovasc Surg. Oct 1992;104(4):945-53. [Medline].

  52. Roach RM, Tandon R, Moller JH, Edwards JE. Ebstein's anomaly of the tricuspid valve in persistent common atrioventricular canal. Am J Cardiol. Feb 1 1984;53(4):640-2. [Medline].

  53. Rosenthal GL, Wilson PD, Permutt T, et al. Birth weight and cardiovascular malformations: a population-based study. The Baltimore-Washington Infant Study. Am J Epidemiol. Jun 15 1991;133(12):1273-81. [Medline].

  54. Ross DA, Nanton M, Gillis DA, Murphy DA. Atrioventricular canal defects: results of repair in the current era. J Card Surg. Sep 1991;6(3):367-72. [Medline].

  55. Sakamoto K, Galletti L, Touchot A, et al. Two-stage correction of transposition of great arteries with complete atrioventricular canal. Ann Thorac Surg. Jan 1998;65(1):250-2. [Medline].

  56. Sheffield VC, Pierpont ME, Nishimura D, et al. Identification of a complex congenital heart defect susceptibility locus by using DNA pooling and shared segment analysis. Hum Mol Genet. Jan 1997;6(1):117-21. [Medline].

  57. Sigfusson G, Ettedgui JA, Silverman NH, Anderson RH. Is a cleft in the anterior leaflet of an otherwise normal mitral valve an atrioventricular canal malformation?. J Am Coll Cardiol. Aug 1995;26(2):508-15. [Medline].

  58. Silverman NH, Zuberbuhler JR, Anderson RH. Atrioventricular septal defects: cross-sectional echocardiographic and morphologic comparisons. Int J Cardiol. Dec 1986;13(3):309-31. [Medline].

  59. Sim EK, Black MD, Smallhorn J, et al. Surgical repair of complete atrioventricular septal canal defects with absent posterior leaflet. Ann Thorac Surg. Nov 1995;60(5):1399-400. [Medline].

  60. Snir E, Raanani E, Birk E, et al. Total cavopulmonary connection (TCPC) for complicated congenital heart malformations. J Cardiovasc Surg (Torino). Dec 1994;35(6 Suppl 1):141-4. [Medline].

  61. Tanaka M, Wechsler SB, Lee IW, et al. Complex modular cis-acting elements regulate expression of the cardiac specifying homeobox gene Csx/Nkx2.5. Development. Apr 1999;126(7):1439-50. [Medline].

  62. Tedziagolska M. Two-patch repair of atrioventricular canal. Ann Thorac Surg. May 1996;61(5):1589-90. [Medline].

  63. Tennant SN, Hammon JW Jr, Bender HW Jr, et al. Familial clustering of atrioventricular canal defects. Am Heart J. Jul 1984;108(1):175-7. [Medline].

  64. Tevosian SG, Deconinck AE, Tanaka M, et al. FOG-2, a cofactor for GATA transcription factors, is essential for heart morphogenesis and development of coronary vessels from epicardium. Cell. Jun 23 2000;101(7):729-39. [Medline].

  65. Torfs CP, Christianson RE. Anomalies in Down syndrome individuals in a large population-based registry. Am J Med Genet. Jun 5 1998;77(5):431-8. [Medline].

  66. van Son JA, Kinzel P, Mohr FW. Repair of Ebstein's anomaly associated with partial atrioventricular canal. J Card Surg. Nov-Dec 1997;12(6):434-6. [Medline].

  67. van Son JA, Phoon CK, Silverman NH, Haas GS. Predicting feasibility of biventricular repair of right-dominant unbalanced atrioventricular canal. Ann Thorac Surg. Jun 1997;63(6):1657-63. [Medline].

  68. van Son JA, Van Praagh R, Falk V, Mohr FW. Pericardial patch augmentation of the tissue-deficient mitral valve in common atrioventricular canal. J Thorac Cardiovasc Surg. Oct 1996;112(4):1117-9. [Medline].

  69. Wenink AC, Zevallos JC. Developmental aspects of atrioventricular septal defects. Int J Cardiol. Jan 1988;18(1):65-78. [Medline].

  70. Westaby S. Monocusp homograft VSD patch in atrioventricular canal with tetralogy of Fallot. Ann Thorac Surg. Jul 1993;56(1):161-3. [Medline].

  71. Westerman GR, Norton JB, Van Devanter SH. Double-outlet right atrium associated with tetralogy of Fallot and common atrioventricular valve. J Thorac Cardiovasc Surg. Feb 1986;91(2):205-7. [Medline].

  72. Yamaki S, Yasui H, Kado H, et al. Pulmonary vascular disease and operative indications in complete atrioventricular canal defect in early infancy. J Thorac Cardiovasc Surg. Sep 1993;106(3):398-405. [Medline].

  73. Yasui H, Morishima M, Nakazawa M, Aikawa E. Anomalous looping, atrioventricular cushion dysplasia, and unilateral ventricular hypoplasia in the mouse embryos with right isomerism induced by retinoic acid. Anat Rec. Feb 1998;250(2):210-9. [Medline].

  74. Zellers TM, Zehr R, Weinstein E, et al. Two-dimensional and Doppler echocardiography alone can adequately define preoperative anatomy and hemodynamic status before repair of complete atrioventricular septal defect in infants <1 year old. J Am Coll Cardiol. Nov 15 1994;24(6):1565-70. [Medline].

  75. Zion MM, Rosenman D, Balkin J, Glaser J. Complete atrioventricular canal with survival to the eighth decade. Chest. Mar 1984;85(3):437-8. [Medline].

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Further Reading

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Keywords

complete atrioventricular septal defect, AVSD, endocardial cushion defect, ECD, common AV canal defect, AVC defect, CAVC, ostium primum atrial septal defect, posterior ventricular septal defect, VSD, congestive heart failure, CHF, Eisenmenger syndrome, tachypnea, Down syndrome, Dandy-Walker malformation, Joubert syndrome, Ritscher-Schintal syndrome

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Contributor Information and Disclosures

Author

Michael McConnell, MD, Department of Pediatrics, Division of Cardiology, Clinical Associate Professor of Pediatrics, Clinical Assistant Professor, Children's Healthcare of Atlanta and Emory University
Michael McConnell, MD is a member of the following medical societies: American Academy of Pediatrics and American College of Cardiology
Disclosure: Nothing to disclose.

Coauthor(s)

John Scheitler, MD, Consulting Staff, Piedmont Adult and Pediatric Medicine Associates, PA
John Scheitler, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Physicians, and Sigma Xi
Disclosure: Nothing to disclose.

Medical Editor

Paul M Seib, MD, Associate Professor of Pediatrics, University of Arkansas for Medical Sciences; Medical Director, Cardiac Catheterization Laboratory, Co-Medical Director, Cardiovascular Intensive Care Unit, Arkansas Children's Hospital
Paul M Seib, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Cardiology, American Heart Association, Arkansas Medical Society, International Society for Heart and Lung Transplantation, and Society for Cardiac Angiography and Interventions
Disclosure: Nothing to disclose.

Pharmacy Editor

Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine.com, Inc
Disclosure: Nothing to disclose.

Managing Editor

Alvin J Chin, MD, Professor of Pediatrics, Division of Cardiology, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine
Alvin J Chin, MD is a member of the following medical societies: American Association for the Advancement of Science and American Heart Association
Disclosure: Nothing to disclose.

CME Editor

Gilbert Herzberg, MD, Assistant Professor, Department of Pediatrics, Section of Pediatric Cardiology, New York Medical College
Gilbert Herzberg, MD is a member of the following medical societies: American Academy of Pediatrics
Disclosure: Nothing to disclose.

Chief Editor

Steven Neish, MD, Director of Pediatric Cardiology Fellowship Program, Department of Pediatrics, Baylor College of Medicine; Clinical Director of Pediatric Cardiology, Texas Children's Heart Center; Director, Brown Foundation Heart Clinic, Texas Children's Hospital
Steven Neish, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Cardiology, and American Heart Association
Disclosure: Nothing to disclose.

 
 
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