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

Single Ventricle

Author: Alvin J Chin, MD, Professor of Pediatrics, Division of Cardiology, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine
Contributor Information and Disclosures

Updated: Jul 15, 2009

Introduction

Background

Using gross anatomic criteria, single ventricle is arbitrarily defined here as a heart that is missing the smooth (ie, nontrabeculated) inflow region of either ventricle. Most cases of tricuspid atresia and mitral atresia retain at least a remnant of this smooth septal aspect of the right ventricle (RV) or left ventricle (LV), respectively. Thus, the atrioventricular connection in single ventricle is either double-inlet (2 or more [if a double-outlet atrium is also present] atrioventricular orifices) or common-inlet (common atrioventricular orifice).
 
With more understanding of cardiovascular morphogenesis, the morphologic RV and morphologic LV may eventually be defined with molecular markers. Currently, the most reliable antemortem methods of identifying single ventricle are 2-dimensional echocardiography and MRI.

Much of the surgical literature over the last 30 years uses a functional definition; namely, that single ventricle is present when 1 of the 2 ventricles is small enough that a series circuit (systemic venous return to ventricle 1 to pulmonary arteries to pulmonary venous return to ventricle 2 to systemic arteries) is incompatible with survival.

Until the early 1970s, surgical management did not include separating the pulmonary and systemic circulations. Modifications of the procedure initially proposed in 1971 by Fontan for tricuspid atresia have been widely adopted in the last 2 decades.1,2 These cavopulmonary or atriopulmonary modifications effectively channel the systemic venous blood directly into the pulmonary arteries.3,4 Whether the effect on overall quality of life is superior to that of the more limited palliations used before 1971 is still unclear.

Hepatic and biliary dysfunction, protein-losing enteropathy, and, most ominously, disadvantageous ejection efficiency combined with elevated afterload characterize Fontan-type circulation.5 Other important sequelae include atrial tachyarrhythmias, short stature, thromboembolism, systemic venous-to-pulmonary venous collaterals, systemic artery-to-pulmonary artery collaterals, plastic bronchitis, and esophageal varices.

Single LV is a relatively uncommon disorder in which the RV is rudimentary and consists of only an arterial outflow. The single LV communicates with the rudimentary RV via a bulboventricular foramen (outlet foramen). The rarely observed single RV occurs when no discernible LV is present. Both atria connect to the single ventricle via either a common atrioventricular valve (sometimes termed the common-inlet ventricle) or separate atrioventricular valves (double-inlet ventricle). Single ventricle most frequently occurs with transposition, but any ventriculoarterial alignment can be seen. Subpulmonary stenosis is more prevalent than the combination of aortic arch obstruction and subaortic stenosis. Although rare, single ventricle can occur without stenosis of either pulmonary or aortic outflow.

The embryology of single ventricle is still unknown. Interestingly, single LV rarely occurs with heterotaxy syndrome. Presumably, both ventricular septation and movement of the common atrioventricular orifice are disrupted. In fact, many genetic alterations can likely result in a single ventricle phenotype. At least 10 single-gene targeted disruptions in mice have already been reported to result in single ventricle prenatally, including Nkx2.5, Isl1;6 Mef2c;7 Hand2;8 Fog-2;9 Fgf8 hypomorph;10 Foxh1;11 TGF b 2;12 Bop2;13 and Has2.14  The Fog -2 null mouse also displays a common atrioventricular orifice situated almost entirely over the future LV.

Pathophysiology

No circulatory derangement is observed in fetal development because pulmonary circulation and systemic circulation are normally in parallel, with 2 levels of connection: atrial and ductal. However, lack of separation between pulmonary and systemic circulations causes obvious cyanosis postnatally, with severity dependent on the degree of coexistent subpulmonary stenosis. Although cases of single ventricle and arch obstruction are the least cyanotic because they never display subpulmonary stenosis, such patients are vulnerable to poor lower body perfusion upon reduction in ductal diameter.

Frequency

United States

Single ventricle occurs in approximately 5 of every 100,000 live births.

Mortality/Morbidity

The severity and timing of presentation depend on the extent of coexistent subpulmonary stenosis (or, alternatively, aortic obstruction) and on reduction in caliber of the ductus arteriosus.

Sex

No disparities are known.

Age

Presentation is generally within the first month of life. As the ductus arteriosus reduces in caliber within the first few days of life, those infants with severe subpulmonary stenosis or aortic obstruction present with cyanosis or poor peripheral perfusion, respectively.

Clinical

History

  • Neonates with single ventricle and subpulmonary stenosis become cyanotic but are usually without other symptoms.
  • Neonates with single ventricle and aortic obstruction may have rapid breathing, lethargy, and poor feeding.

Physical

  • Cyanosis is present in patients with subpulmonary stenosis.
  • Poor peripheral perfusion is evident in patients with single ventricle with aortic obstruction.
  • If aortic obstruction involves coarctation or interruption, then a difference in blood pressure is observed between the right arm and a lower extremity, unless the right subclavian artery is aberrant. 
  • The first heart sound is normal.
  • The second heart sound is single.
  • A systolic ejection murmur is present in those with subpulmonary stenosis as well as those with aortic obstruction.

Causes

  • The cause of single ventricle in humans is unknown.
  • So far, at least 10 targeted single-gene disruptions in mice have produced a right ventricular (RV) hypoplasia phenotype reminiscent of single left ventricle (LV). These disruptions include global nulls in Nkx2.5, Isl1;6 Mef2c;7 dHand (also known as Hand2);8 Fog-2;9 Fgf8 hypomorph;10 Foxh1;11 TGF b 2;12 Bop2;13 and Has2.14 The Fog -2 null also displays a common atrioventricular orifice situated almost entirely over the future LV. Whether hypomorphic alleles of the homologous mutations in the human produce a single ventricle phenotype but do not result in embryonic lethality remains to be shown.
  • Myocardial-specific inactivation of GATA4 also causes single ventricle.15

More on Single Ventricle

Overview: Single Ventricle
Differential Diagnoses & Workup: Single Ventricle
Treatment & Medication: Single Ventricle
Follow-up: Single Ventricle
Multimedia: Single Ventricle
References
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References

  1. Fontan F, Mounicot FB, Baudet E, et al. ["Correction" of tricuspid atresia. 2 cases "corrected" using a new surgical technic]. Ann Chir Thorac Cardiovasc. Jan 1971;10(1):39-47. [Medline].

  2. Bull K. The Fontan procedure: lessons from the past. Heart. Mar 1998;79(3):213-4. [Medline].

  3. de Zelicourt DA, Pekkan K, Wills L, et al. In vitro flow analysis of a patient-specific intraatrial total cavopulmonaryconnection. Ann Thorac Surg. Jun 2005;79(6):2094-102. [Medline].

  4. Earing MG, Cetta F, Driscoll DJ, Mair DD, Hodge DO, Dearani JA. Long-term results of the Fontan operation for double-inlet left ventricle. Am J Cardiol. Jul 15 2005;96(2):291-8. [Medline].

  5. Senzaki H, Masutani S, Kobayashi J, et al. Ventricular afterload and ventricular work in fontan circulation: comparison with normal two-ventricle circulation and single-ventricle circulation with blalock-taussig shunts. Circulation. Jun 18 2002;105(24):2885-92. [Medline].

  6. Cai CL, Liang X, Shi Y, Chu PH, Pfaff SL, Chen J. Isl1 identifies a cardiac progenitor population that proliferates prior to differentiation and contributes a majority of cells to the heart. Dev Cell. Dec 2003;5(6):877-89. [Medline].

  7. Lin Q, Schwarz J, Bucana C, Olson EN. Control of mouse cardiac morphogenesis and myogenesis by transcription factor MEF2C. Science. May 30 1997;276(5317):1404-7. [Medline].

  8. Srivastava D, Thomas T, Lin Q, et al. Regulation of cardiac mesodermal and neural crest development by the bHLH transcription factor, dHAND. Nat Genet. Jun 1997;16(2):154-60. [Medline].

  9. Svensson EC, Huggins GS, Lin H, et al. A syndrome of tricuspid atresia in mice with a targeted mutation of the gene encoding Fog-2. Nat Genet. Jul 2000;25(3):353-6. [Medline].

  10. Ilagan R, Abu-Issa R, Brown D, Yang YP, Jiao K, Schwartz RJ. Fgf8 is required for anterior heart field development. Development. Jun 2006;133(12):2435-45. [Medline].

  11. von Both I, Silvestri C, Erdemir T, Lickert H, Walls JR, Henkelman RM. Foxh1 is essential for development of the anterior heart field. Dev Cell. Sep 2004;7(3):331-45. [Medline].

  12. Sanford LP, Ormsby I, Gittenberger-de Groot AC, Sariola H, Friedman R, Boivin GP. TGFbeta2 knockout mice have multiple developmental defects that are non-overlapping with other TGFbeta knockout phenotypes. Development. Jul 1997;124(13):2659-70. [Medline].

  13. Gottlieb PD, Pierce SA, Sims RJ, Yamagishi H, Weihe EK, Harriss JV. Bop encodes a muscle-restricted protein containing MYND and SET domains and is essential for cardiac differentiation and morphogenesis. Nat Genet. May 2002;31(1):25-32. [Medline].

  14. Camenisch TD, Spicer AP, Brehm-Gibson T, Biesterfeldt J, Augustine ML, Calabro A Jr. Disruption of hyaluronan synthase-2 abrogates normal cardiac morphogenesis and hyaluronan-mediated transformation of epithelium to mesenchyme. J Clin Invest. Aug 2000;106(3):349-60. [Medline].

  15. Zeisberg EM, Ma Q, Juraszek AL, Moses K, Schwartz RJ, Izumo S. Morphogenesis of the right ventricle requires myocardial expression of Gata4. J Clin Invest. Jun 2005;115(6):1522-31. [Medline].

  16. Narkewicz MR, Sondheimer HM, Ziegler JW, et al. Hepatic dysfunction following the Fontan procedure. J Pediatr Gastroenterol Nutr. Mar 2003;36(3):352-7. [Medline].

  17. Chin AJ, Stephens P, Goldmuntz E, Leonard MB. Serum alkaline phosphatase reflects post-Fontan hemodynamics in children. Pediatr Cardiol. Feb 2009;30(2):138-45. [Medline].

  18. Durongpisitkul K, Porter CJ, Cetta F, et al. Predictors of early- and late-onset supraventricular tachyarrhythmias after Fontan operation. Circulation. Sep 15 1998;98(11):1099-107. [Medline].

  19. Jacobs ML, Rychik J, Rome JJ, et al. Early reduction of the volume work of the single ventricle: the hemi-Fontan operation. Ann Thorac Surg. Aug 1996;62(2):456-61; discussion 461-2. [Medline].

  20. Jacobs ML, Norwood WI Jr. Fontan operation: influence of modifications on morbidity and mortality. Ann Thorac Surg. Oct 1994;58(4):945-51; discussion 951-2. [Medline].

  21. Canobbio MM, Mair DD, van der Velde M, Koos BJ. Pregnancy outcomes after the Fontan repair. J Am Coll Cardiol. Sep 1996;28(3):763-7. [Medline].

  22. Camposilvan S, Milanesi O, Stellin G, Pettenazzo A, Zancan L, D'Antiga L. Liver and cardiac function in the long term after Fontan operation. Ann Thorac Surg. Jul 2008;86(1):177-82. [Medline].

  23. Yeh T, Williams WG, McCrindle BW, et al. Equivalent survival following cavopulmonary shunt: with or without the Fontan procedure. Eur J Cardiothorac Surg. Aug 1999;16(2):111-6. [Medline].

  24. Bromberg BI, Schuessler RB, Gandhi SK, et al. A canine model of atrial flutter following the intra-atrial lateral tunnel Fontan operation. J Electrocardiol. 1998;30 Suppl:85-93. [Medline].

  25. Mavroudis C, Deal BJ, Backer CL, Stewart RD, Franklin WH, Tsao S. J. Maxwell Chamberlain Memorial Paper for congenital heart surgery. 111 Fontan conversions with arrhythmia surgery: surgical lessons and outcomes. Ann Thorac Surg. Nov 2007;84(5):1457-65; discussion 1465-6. [Medline].

  26. Petrossian E, Reddy VM, McElhinney DB, et al. Early results of the extracardiac conduit Fontan operation. J Thorac Cardiovasc Surg. Apr 1999;117(4):688-96. [Medline].

  27. Kiesewetter CH, Sheron N, Vettukattill JJ, Hacking N, Stedman B, Millward-Sadler H. Hepatic changes in the failing Fontan circulation. Heart. May 2007;93(5):579-84. [Medline].

  28. Wilson WR, Greer GE, Tobias JD. Cerebral venous thrombosis after the Fontan procedure. J Thorac Cardiovasc Surg. Oct 1998;116(4):661-3. [Medline].

  29. Cohen MI, Rhodes LA, Wernovsky G, Gaynor JW, Spray TL, Rychik J. Atrial pacing: an alternative treatment for protein-losing enteropathy after the Fontan operation. J Thorac Cardiovasc Surg. Mar 2001;121(3):582-3. [Medline].

  30. Cheung YF, Tsang HY, Kwok JS. Immunologic profile of patients with protein-losing enteropathy complicating congenital heart disease. Pediatr Cardiol. Nov-Dec 2002;23(6):587-93. [Medline].

  31. Pekkan K, Kitajima HD, de Zelicourt D, et al. Total cavopulmonary connection flow with functional left pulmonary artery stenosis: angioplasty and fenestration in vitro. Circulation. Nov 22 2005;112(21):3264-71. [Medline].

  32. Jacobs ML, Schneider DJ, Pourmoghadam KK, Pizarro C, Norwood WI. Total cavopulmonary connection to one lung. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2004;7:72-9. [Medline].

  33. Troutman WB, Barstow TJ, Galindo AJ, Cooper DM. Abnormal dynamic cardiorespiratory responses to exercise in pediatric patients after Fontan procedure. J Am Coll Cardiol. Mar 1 1998;31(3):668-73. [Medline].

  34. Chang RK, Alejos JC, Atkinson D, et al. Bubble contrast echocardiography in detecting pulmonary arteriovenous shunting in children with univentricular heart after cavopulmonary anastomosis. J Am Coll Cardiol. Jun 1999;33(7):2052-8. [Medline].

  35. Barber BJ, Burch GH, Tripple D, Balaji S. Resolution of plastic bronchitis with atrial pacing in a patient with fontan physiology. Pediatr Cardiol. Jan-Feb 2004;25(1):73-6. [Medline].

  36. Wilson J, Russell J, Williams W, Benson L. Fenestration of the Fontan circuit as treatment for plastic bronchitis. Pediatr Cardiol. Sep-Oct 2005;26(5):717-9. [Medline].

  37. Semenza GL. Expression of hypoxia-inducible factor 1: mechanisms and consequences. Biochem Pharmacol. Jan 1 2000;59(1):47-53. [Medline].

  38. Deal BJ, Backer CL, Ward KM, Tsao S, Dechert B, de Freitas A, et al. Medical characteristics and mid-term outcome: 100 consecutive Fontan conversions with arrhythmia surgery. Circulation. 2007;116:II-414.

  39. Kaushansky K. Lineage-specific hematopoietic growth factors. N Engl J Med. May 11 2006;354(19):2034-45. [Medline].

  40. Rydberg A, Teien DE, Krus P. Computer simulation of circulation in patient with total cavo-pulmonary connection: inter-relationship of cardiac and vascular pressure, flow, resistance and capacitance. Med Biol Eng Comput. Nov 1997;35(6):722-8. [Medline].

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Further Reading

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Keywords

single ventricle, single left ventricle, single right ventricle, tricuspid atresia, mitral atresia, double-inlet single ventricle, common-inlet single ventricle, hepatic dysfunction, biliary dysfunction, protein-losing enteropathy, subpulmonary stenosis, aortic arch obstruction, aortic arch hypoplasia, subaortic stenosis, cyanosis, peripheral perfusion, Fontan operation, hypoproteinemia, L-looped single left ventricle, transposition of the great arteries, D-looped single left ventricle, bulboventricular foramen, outlet foramen, bidirectional Glenn operation, hemi-Fontan operation, pulmonary artery distortion, pericardial effusion, pleural effusion, ascites, thrombus, sinus bradycardia, atrial tachyarrhythmias, varices, plastic bronchitis, thrombocytopenia, systemic collaterals, short stature, treatment, diagnosis

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Contributor Information and Disclosures

Author

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.

Medical Editor

Juan Carlos Alejos, MD, Clinical Professor, Department of Pediatrics, Division of Cardiology, University of California at Los Angeles
Juan Carlos Alejos, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Cardiology, American Heart Association, American Medical Association, and International Society for Heart and Lung Transplantation
Disclosure: Actelion Honoraria Speaking and teaching

Pharmacy Editor

Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine
Disclosure: Pfizer Inc Stock Investment from financial planner; Avanir Pharma Stock Investment from financial planner ; WebMD Salary and stock Employment and investment from financial planner

Managing Editor

Ameeta Martin, MD, Clinical Associate Professor, Department of Pediatric Cardiology, University of Nebraska College of Medicine
Ameeta Martin, MD is a member of the following medical societies: American College of Cardiology
Disclosure: Nothing to disclose.

CME Editor

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

Chief Editor

Stuart Berger, MD, Professor of Pediatrics, Division of Cardiology, Medical College of Wisconsin; Chief of Pediatric Cardiology, Medical Director of Pediatric Heart Transplant Program, Medical Director of The Heart Center, Children's Hospital of Wisconsin
Stuart Berger, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Cardiology, American College of Chest Physicians, American Heart Association, and Society for Cardiac Angiography and Interventions
Disclosure: Nothing to disclose.

 
 
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