The impact of extracardiac conduit-total cavopulmonary connection on apicocaval juxtaposition

Modifications of the Fontan procedure are applied to a wide range of complex congenital heart defects with single ventricle physiology. We examined the pathway and the clinical results of extracardiac conduit-total cavopulmonary connection (EC-TCPC) for a malpositioned heart with apicocaval juxtaposition.

Of the 365 patients who underwent EC-TCPC since 1994, 56 patients with a malpositioned heart with apicocaval juxtaposition were included in this retrospective study (group 1). The pathway for the EC was selected after careful consideration of the results of preoperative angiography and computed tomography, as well as intra-operative findings. A concurrent group of 299 patients undergoing EC-TCPC without apicocaval juxtaposition was used as a control group (group 2). The mean follow-up periods for groups 1 and 2 were 5.5 years (range: 0-12 years) and 5.5 years (range: 0-14 years), respectively.

The mean age at operation was 4.2±3.2 years and the median size of the conduit was 18 mm (range: 16-20mm). In 30 patients, the conduit was placed between the inferior vena cava (IVC) and the opposite side of the pulmonary artery crossing the vertebra. In another 25 patients, the conduit was positioned behind the ventricle between the IVC and on the same side as the pulmonary artery (PA). There was one patient who had a Y-style conduit placed between the IVC and right and left PAs behind the ventricle. In group 1, there were no early deaths; three patients died in the intermediate term due to gastric bleeding in one, haemoptysis in another and sudden death in yet another. None of the patients developed conduit stenosis or pulmonary venous obstruction, and no patient required re-operation. Three patients developed late complications, including arrhythmias requiring medication in two and subdural haematoma in one. The incidence of death or late complications did not differ among the pathways of conduits. In group 2, there were eight late deaths, and 27 patients developed late complications. The Kaplan-Meier survival rate was 93.5% at 5 and 10 years in group 1, and 97.3% at 5 years and 96.1% at 10 years in group 2 (log-rank test, P=0.29). The haemodynamics in groups 1 and 2 during the intermediate term were identical with respect to IVC pressure (8.9 ± 2.5 in group 1 and 9.6 ± 2.6mmHg in group 2), left ventricular end-diastolic pressure (4.4 and 4.3 mmHg, respectively), cardiac index (3.3 and 3.4 l min(-1)m(-2), respectively) and arterial oxygen saturation (94 and 94.2%, respectively). No patient in either group had a pressure gradient >2 mmHg between the IVC and central PA. Postoperative catheterisation data showed no significant differences in haemodynamics between the conduit pathways in group 1.

EC-TCPC can be performed in children with apicocaval juxtaposition with excellent mid-term outcomes compared with other Fontan candidates. Based on individual cardiac anatomy, the pathway of the EC behind the ventricle or crossing the vertebra can be used without conduit stenosis or pulmonary venous obstruction.