AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Background

Polysplenia is a heterogeneous disease that primarily affects the asymmetric organs, including the heart, lungs and bronchi, liver, intestines, and spleen. Primary manifestations of this disease include cyanotic congenital heart disease, biliary atresia, intestinal malrotation, and functional asplenia.

Pathophysiology

The exact cause of polysplenia has not been defined, but it appears to be multifactorial, with some familial predisposition. Embryologically, it results from failure of development of right-left asymmetry. Several candidate genes have been suggested as causing failure of lateralization, and genetically engineered animal models have similar findings.

Frequency

United States

Polysplenia accounts for approximately 0.4% of cases of congenital heart disease and occurs in an estimated 4 per 1 million live births.

Mortality/Morbidity

Approximately 80% of patients with polysplenia have congenital heart disease. Mortality can result from congenital heart disease, biliary atresia, intestinal malrotation, or sepsis. In one large retrospective review from Canada, the 1-year mortality rate was 32% and the 15-year mortality rate was 49%.

Race

No predisposition based on race has been reported.

Sex

No predisposition based on sex has been reported. However, polysplenia has been reported to sometimes be transmitted in an X-linked recessive fashion.

Age

Polysplenia is present from birth, although clinical detection may be delayed, depending on the severity of congenital heart disease and gastrointestinal abnormalities.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

History

Patients most commonly present with symptoms of congenital heart disease in the newborn period. Jaundice caused by biliary tract abnormalities is the second most common neonatal presentation. A small percentage of patients present with abdominal symptoms or are diagnosed because of an incidental finding of situs abnormalities (eg, dextrocardia, intestinal malrotation).

Physical

Cyanosis, congestive heart failure, and persistent jaundice are the most common physical findings in patients who present in the newborn period. For patients who present later, isolated dextrocardia (with right-sided heart sounds) and a transverse liver may be the only abnormalities observed on physical examination.

Causes

The cause(s) of polysplenia syndrome are unknown but are believed to be multifactorial. The incidence of polysplenia has not been studied extensively, but it appears to be rare, comprising less than 1% of congenital heart defects. In a 26-year retrospective study at the Hospital for Sick Children in Toronto Canada, only 91 cases were identified. Familial cases have been reported, along with single-family reports of gene linkage. However, no reproducible patterns of inheritance have been identified, nor has a gene for this disease been identified. Different forms of heterotaxy, including asplenia and polysplenia, may occur within the same family. Animal studies have implicated several genes as possible causes of polysplenia syndrome. Retinoic acid has been implicated as a cause of polysplenia syndrome in mouse embryos.

Polysplenia syndrome is commonly associated with other defects of lateralization, including intestinal malrotation, transverse liver, and genitourinary abnormalities.

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Situs inversus (Kartagener syndrome)

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Lab Studies

• Useful laboratory studies include a CBC count with peripheral smear to look for Howell-Jolly bodies and evidence of impaired splenic function.
• Arterial blood gas measurements to assess for cyanotic heart disease may also be indicated.

Imaging Studies

• Complete echocardiography is indicated in any patient with suspected polysplenia to evaluate for associated congenital heart disease.
• Routine chest radiography is indicated to assess the cardiac size and location, the bronchial anatomy (usually bilateral left bronchi are present), and abdominal situs.
• In addition, an upper GI study has been proposed as a routine study in patients with polysplenia because of the high incidence of intestinal malrotation and the risk of volvulus.
• Liver-spleen scanning and abdominal ultrasonography are useful for determination of organ size, location, and function. Liver-spleen scanning is indicated to confirm the presence of functional splenic tissue. The presence of multiple small spleens is common in polysplenia.

Other Tests

• A 12-lead ECG is often helpful because an abnormal P wave axis is common in patients with polysplenia, and conduction system abnormalities (eg, complete heart block, sick sinus syndrome, supraventricular tachycardia [SVT]) are common.
• Additional studies of cardiac conduction, particularly 24-hour Holter monitoring, may be indicated by the clinical setting.
• Additional studies of the biliary tract may be indicated in patients with prolonged jaundice or other signs of biliary atresia.

Procedures

• Cardiac catheterization
• • Patients presenting with cardiac malformations often require cardiac catheterization on one or more occasions. In the newborn period, cardiac catheterization may be indicated to assess systemic and pulmonary venous connections. Later, cardiac catheterization may be indicated to determine individual candidacy for surgical intervention.
  • Cardiac catheterization can often be carried out with a venous approach, accessing the left heart through an atrial septal defect (ASD) or patent foramen ovale (PFO). This is particularly important in the newborn period when small vessel size can increase the risk of vascular complication. Although no data exist, the authors' experience with catheterization via the umbilical vein has suggested that many patients with heterotaxy syndrome have an abnormal ductus venosus, making cannulation difficult. However, umbilical venous cannulation is possible and can preserve femoral access for future interventions.
  • The goals of diagnostic catheterization are usually to provide hemodynamic and physiologic data to assist with medical and surgical decision-making. Anatomic information is rarely required in the era of modern echocardiography. Echocardiography can be limited in assessing pulmonary venous return, branch pulmonary artery anatomy, and aortopulmonary collaterals, so these issues occasionally require clarification via cardiac catheterization.
  • Postcatheterization precautions include hemorrhage, vascular disruption after balloon dilation, pain, nausea and vomiting, and arterial or venous obstruction from thrombosis or spasm.
  • Possible complications include rupture of blood vessel, tachyarrhythmias, bradyarrhythmias, and vascular occlusion.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical Care

Medical therapy is typically directed at the findings of the initial evaluation. Anticongestive medication is often required in patients with significant left-to-right shunts. Patients with functional asplenia require antibiotic prophylaxis and the pneumococcal vaccine.

Surgical Care

Surgical care is also directed at the findings of the initial evaluation. Patients with significant cardiac disease may require staged palliation or definitive repair, whereas patients with biliary atresia may require initial palliative surgery followed by liver transplantation.

Consultations

Patients with polysplenia syndrome can present with a variety of noncardiac problems, primarily gastrointestinal tract abnormalities but also genitourinary abnormalities. Patients presenting with evidence of intestinal obstruction, volvulus, or both should have a consultation with a general surgeon and appropriate imaging studies to rule out malrotations. Consultation with an infectious disease specialist may also be warranted if bacterial infection is suspected because patients with polysplenia associated with abnormal splenic function are more susceptible to certain bacterial pathogens.

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Cardiomyopathy with significant left-to-right shunts may require treatment for congestive heart failure. According to American Heart Association guidelines, pneumococcal vaccine and antibiotics for SBE prophylaxis are necessary in patients with functional asplenia. Antibiotic prophylaxis is administered to patients before performing procedures that may cause bacteremia. For more information, see Antibiotic Prophylactic Regimens for Endocarditis.

Drug Category: Diuretic agents

These agents promote excretion of water and electrolytes by the kidneys. They are used to treat heart failure or hepatic, renal, or pulmonary disease when sodium and water retention has resulted in edema or ascites. The agents may be used as monotherapy or combination therapy to treat hypertension.

Drug Category: Inotropic agents

Positive inotropes increase the force of contraction of the myocardium and are used to treat acute and chronic congestive heart failure. Some may also increase or decrease the heart rate (ie, positive or negative chronotropic agents), provide vasodilatation, or improve myocardial relaxation. These additional properties influence the choice of drug for specific circumstances. Those used predominantly for their inotropic effects include cardiac glycosides and phosphodiesterase inhibitors.

Drug Category: Angiotensin-converting enzyme (ACE) inhibitors

ACE inhibitors are beneficial in all stages of congestive heart failure. Pharmacologic effects result in a decrease in systemic vascular resistance, reducing blood pressure, preload, and afterload. Dyspnea and exercise tolerance are improved. Unlike diuretics, studies demonstrate improvement of survival and reduced progression of mild or moderate heart failure to more severe stages. ACE inhibitors benefit asymptomatic left ventricular dysfunction.

Drug Category: Vaccines

Active immunization increases resistance to infection. Vaccines consist of microorganisms or cellular components that act as antigens. Administration of the vaccine stimulates the production of antibodies with specific protective properties.

Drug Category: Antibiotics, prophylactic

Antibiotic prophylaxis is administered to patients before performing procedures that may cause bacteremia.

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Further Inpatient Care

• Follow-up care is dictated by the type of cardiac defect and/or associated noncardiac manifestations. Patients with univentricular physiology typically require staged palliation, repeated hospitalization for preoperative evaluation, and perioperative care. Other inpatient care may be dictated by associated noncardiac lesions.

Further Outpatient Care

• Patients with polysplenia syndrome often have univentricular physiology and/or very complex anatomy requiring staged palliative procedures and lifelong cardiac follow-up.
• Patients with functional asplenia require careful evaluation of fever. They are at risk for overwhelming sepsis. Fevers without obvious cause should be evaluated with a blood culture, and admission for intravenous antibiotics, until the culture results are available, should be considered.

In/Out Patient Meds

• Anticongestive therapy is required in most patients, along with anticoagulation and vasodilator therapy. No consensus exists on the most appropriate medical regimen for these patients, and the broad range of manifestations makes studies regarding the safety and efficacy of drug regimens difficult.
• Many patients with palliated polysplenia syndrome develop arrhythmia, requiring medication. Consensus on the most appropriate antiarrhythmic medications or interventional therapy also is lacking.
• Patients with functional asplenia require antibiotic prophylaxis. The usual regimen is amoxicillin once daily.

Complications

• Complications from polysplenia syndrome can arise from the cardiac defects, the intestinal defects, or the immunodeficiency. The most common cardiac complications are congestive heart failure and arrhythmia. Careful prospective management of pulmonary blood flow, AV valve regurgitation, and cyanosis can help prevent the early onset of ventricular dysfunction and congestive heart failure; however, this complication is nearly universal in these patients. Arrhythmia can result from an absent or poorly functioning sinus node or from intra-atrial reentry around surgical scars. Patients with a history of pulmonary vein repair appear to be particularly prone to this complication. Antiarrhythmic therapy and pacemaker implantation often are required in these cases.
• Gastrointestinal complications usually arise from malrotation with volvulus but can also result from annular pancreas, esophageal or intestinal atresia, and biliary tree abnormalities.
• Complications arising from functional asplenia can include overwhelming sepsis, often leading to loss of extremities or death.

Prognosis

• The prognosis for polysplenia syndrome is closely related to the cardiac manifestations. In a 26-year study period, the overall survival rate in the large series of 91 patients from Toronto was 31%; the 5-year survival rate was less than 40%. Risk factors for poor outcome included unobstructed pulmonary blood flow, obstructed pulmonary venous return, and major AV valve anomalies.

Patient Education

• Patient education usually starts with educating parents on the care of infants with heart disease. The importance of routine follow-up, adherence to the medical regimen, and risk of infection should be stressed. In addition, early discussions about the relatively poor prognosis, potential need for orthotopic heart transplant, and need for multiple palliative procedures often help parents to cope with this chronic condition.

MISCELLANEOUS

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical/Legal Pitfalls

• The most common medicolegal pitfall in this patient population seems to be failure to recognize sepsis in a patient with polysplenia who is functionally asplenic. Rapidly fatal infections are common in asplenic patients and often occur shortly after the onset of fever in an otherwise healthy appearing child. The lack of an ill appearance in these children should not be reassuring. All asplenic patients should be evaluated carefully, and inpatient observation with prophylactic antibiotics should be considered.

Special Concerns

• Patients who survive to childbearing age are generally discouraged from carrying a pregnancy to term because the likelihood of carrying a pregnancy to term is low, and the maternal risk is high. However, patients with polysplenia have survived pregnancies and delivered term healthy babies without congenital heart disease.

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

• Atkinson DE, Drant S. Diagnosis of heterotaxy syndrome by fetal echocardiography. Am J Cardiol. Nov 1 1998;82(9):1147-9, A10. [Medline].
• Bartram U, Wirbelauer J, Speer CP. Heterotaxy syndrome -- asplenia and polysplenia as indicators of visceral malposition and complex congenital heart disease. Biol Neonate. 2005;88(4):278-90. [Medline].
• Belmont JW, Mohapatra B, Towbin JA, Ware SM. Molecular genetics of heterotaxy syndromes. Curr Opin Cardiol. May 2004;19(3):216-20. [Medline]. [Full Text].
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• Ditchfield MR, Hutson JM. Intestinal rotational abnormalities in polysplenia and asplenia syndromes. Pediatr Radiol. May 1998;28(5):303-6. [Medline].
• Gayer G, Apter S, Jonas T, et al. Polysplenia syndrome detected in adulthood: report of eight cases and review of the literature. Abdom Imaging. Mar-Apr 1999;24(2):178-84. [Medline].
• Gilljam T, McCrindle BW, Smallhorn JF, et al. Outcomes of left atrial isomerism over a 28-year period at a single institution. J Am Coll Cardiol. Sep 2000;36(3):908-16. [Medline].
• Hofstaetter C, Plath H, Hansmann M. Prenatal diagnosis of abnormalities of the fetal venous system. Ultrasound Obstet Gynecol. Mar 2000;15(3):231-41. [Medline].
• Ticho BS, Van Praagh R. Inherited structural heart diseases associated with arrhythmias: Defects in laterality. In: Berul CI, Towbin JA, eds. Molecular Genetics of Cardiac Electrophysiology. Boston, Mass:. Kluwer Academic Publishers;2000:317-328.
• Uemura H, Ho SY, Devine WA, Anderson RH. Analysis of visceral heterotaxy according to splenic status, appendage morphology, or both. Am J Cardiol. Oct 15 1995;76(11):846-9. [Medline].
• Uemura H, Ho SY, Anderson RH, Yagihara T. Ventricular morphology and coronary arterial anatomy in hearts with isometric atrial appendages. Ann Thorac Surg. May 1999;67(5):1403-11. [Medline].
• Yoo SJ, Kim YM, Choe YH. Magnetic resonance imaging of complex congenital heart disease. Int J Card Imaging. Apr 1999;15(2):151-60. [Medline].
• Zissin R, Rathaus V, Oscadchy A, et al. Intestinal malrotation as an incidental finding on CT in adults. Abdom Imaging. Nov-Dec 1999;24(6):550-5. [Medline].

Article Last Updated: Apr 13, 2006