Splanchnic circulation constitutes a major portion of the vasculature capacitance and plays an important role in maintaining blood perfusion. Because patients with asplenia syndrome lack this vascular bed as a blood reservoir, they may have a unique blood volume and distribution, which may be related to their vulnerability to the haemodynamic changes often observed in clinical practice. During cardiac catheterisation, the mean circulatory filling pressure was calculated with the Valsalva manoeuvre in 19 patients with Fontan circulation, including 5 patients with asplenia syndrome. We also measured the cardiac output index and circulatory blood volume by using a dye dilution technique. The blood volume and the mean circulatory filling pressure and the venous capacitance in patients with asplenia syndrome were similar to those in the remaining patients with Fontan circulation (85 ± 14 versus 77 ± 18 ml/kg, p = 0.43, 31 ± 8 versus 27 ± 5 mmHg, p = 0.19, 2.8 ± 0.6 versus 2.9 ± 0.9 ml/kg/mmHg, p = 0.86). Unexpectedly, our data indicated that patients with asplenia syndrome, who lack splanchnic capacitance circulation, have blood volume and venous capacitance comparable to those in patients with splanchnic circulation. These data suggest that (1) there is a blood reservoir other than the spleen even in patients with asplenia; (2) considering the large blood pool of the spleen, the presence of a symmetrical liver may represent the possible organ functioning as a blood reservoir in asplenia syndrome; and (3) if this is indeed the case, there may be a higher risk of hepatic congestion in patients with Fontan circulation with asplenia syndrome than in those without.

We report a rare variation in the pattern of totally anomalous pulmonary venous connection in that two vertical veins drained into the left brachiocephalic vein from a common pulmonary venous confluence. The child had associated right isomerism and functionally univentricular heart. Awareness of this possibility may avoid a reoperation or even death.

We describe an infant with severe obstruction of infra-cardiac totally anomalous pulmonary venous connection associated with right isomerism, atrioventricular septal defect, pulmonary atresia, and multiple aortopulmonary collateral arteries. Implantation of a stent into the obstructed descending vertical vein provided effective palliation, with a dramatic increase in saturations of oxygen obviating the need for urgent high-risk surgery.

Despite the close association of certain constellations of cardiac malformations with splenic status (right isomerism / asplenia, left isomerism / polysplenia), the association is not perfect. Given the risk of infection in the patient lacking splenic tissue, it seems prudent to assess the state of the spleen separately from the cardiovascular system, in order to decide on antimicrobial prophylaxis. A wide variety of tests is available to assess splenic function and/or anatomy. Counting pitted erythrocytes or Howell-Jolly bodies in the peripheral blood smear can be a good indicator of the lack of splenic function, although the former appears more sensitive and quantitative than the latter. Radionuclide spleen scans can provide both anatomic and functional information about the spleen, and may be a useful adjunctive test. Relatively poor spatial resolution, and interfering hepatic activity (even with spleen-specific scans), mitigate its usefulness in the young infant. The reliability of computed tomography and magnetic resonance imaging in detecting splenic tissue in the heterotaxy syndromes is unproven and perhaps only fair at best. They are probably most helpful as adjunctive tests. Ultrasonography offers excellent spatial resolution, portability, and lack of ionizing radiation, but is operator- and patient-dependent. Nonetheless, ultrasonography, coupled with an examination of the peripheral blood for Howell-Jolly bodies or pitted erythrocytes, is probably the set of tests with highest sensitivity and greatest convenience. Management strategies for the asplenic patient are also discussed.

The prognosis for the fetus or neonate with asplenia syndrome is unknown as population-based data are unavailable. Factors influencing survival in this syndrome were, therefore, assessed for the province of British Columbia by retrospective review of all cases diagnosed between 1970 and 1990. Particular attention was paid to the prognostic influence of palliative surgery, sepsis, extracardiac malformations, gastrointestinal disease, arrhythmias and sudden death. We identified 43 cases of asplenia syndrome, of which 40 were live-born (incidence 1/22,000 live‐births). Only one spontaneous death was noted during fetal life amongst approximately 5,000 fetal autopsies. Five cases had been diagnosed by fetal echocardiography, two of these pregnancies being terminated. Of the live-born infants, 28 (70%) underwent active management of their cardiac anomalies and of these, 14 are alive. Since 1980, 26 systemic-to‐pulmonary shunts have been constructed in 17 children with two operative deaths. Three children have had successful Fontan or bidirectional Glenn procedures. Systemic sepsis occurred in three children with no deaths. Three neonates underwent surgery for obstruction of the upper gastrointestinal tract without complication. Late sudden death occurred in four children with systemic-to-pulmonary shunts, none of whom had documented arrhythmias. Major extracardiac malformations were present in nine cases (21%), these contributing to death in two. Overall survival for all live-born infants is 35%. Sepsis and palliative surgery are no longer the major causes of death in asplenia syndrome, the current challenges being prevention of sudden death and the complexity of surgical repair of the cardiac malformations.

The incidence and spectrum of extracardiac malformations in congenital asplenia syndrome were determined by review of43 cases (40 live-births) identified in the province of British Columbia over a 21 year period. Major extracardiac anomalies (excluding those of abnormal arrangement of the organs) were identified in nine cases (21%), and minor anomalies were present in an additional twelve infants (28%). Extracardiac anomalies were associated with one spontaneous stillbirth, one termination of pregnancy, and two early neonatal deaths. In an additional four newborns, they contributed to a decision not to palliate the complex cardiac anomalies. Gastrointestinal malformations led to neonatal intestinal obstruction in four infants. Of the 14 surviving children, one is severely handicapped due to a congenital anomaly of the central nervous system. The clinical significance of extracardiac malformations and their developmental implications are discussed.

The heterotaxy syndromes are characterized by a high incidence of cardiac anomalies of extreme heterogeneity. Due to this, the surgical management is varied and challenging. Although a minority of patients can undergo biventricular repair, the complexity of the cardiac defects, and the high incidence of ventricular hypoplasia, mandate a surgical approach in the majority of patients depending on the creation of a functionally univentricular heart. Traditionally, the functionally univentricular approach was associated with a high mortality. More recently, the results have been improving as a result of better understanding of these malformations, and logical improvements in surgical technique. In this review, we will make brief comments on the nomenclature and classification of the heterotaxy syndromes, and the range of cardiac anomalies, before concentrating on the surgical treatment for those patients having functionally univentricular hearts in the setting of heterotaxy. More specifically, we will review initial palliation in early life, creation of the cavopulmonary anastomoses, including the Kawashima procedure and the Fontan circulation, and the role of transplantation.

It has long been known that the most complex combinations of cardiac malformations are those found in the setting of the so-called “splenic syndromes”.1 Many aspects of these syndromes have been controversial over recent years, not least the presence or absence of features of isomerism within the heart.2,3 Recent experience with genetic manipulation of mice, nonetheless, has now shown that it is possible to generate unequivocal evidence of cardiac isomerism, particularly in those animals which show features of right isomerism when the genes responsible for morphologically leftness are knocked out.4 Furthermore, when the crucial philosophical principle known as the “morphological method”5 is applied to the hearts of patients known to have visceral heterotaxy, it is equally clear that patients falling within these groups, when judged on the extent of the pectinate muscles relative to the atrioventricular junctions, exhibit isomerism of either the morphologically right or left atrial appendages.3