Common Arterial Trunk With Atrioventricular Septal Defect: New Observations Pertinent to Repair

Atrioventricular Septal Defect With Tetralogy of Fallot and Exclusive Shunting at the Ventricular Level

Atrioventricular septal defect (AVSD) with shunting restricted to the ventricular level is a rare form of AVSD. To our knowledge, this shunting pattern has not been reported in AVSD with tetralogy of Fallot. We report a child with this unusual combination who underwent a successful single-stage repair at two years of age.

Common Arterial Trunk Associated with Functionally Univentricular Heart: Anatomical Study and Review of the Literature

Common arterial trunk (CAT) is a rare congenital heart disease that is commonly included into the spectrum of conotruncal heart defects. CAT is rarely associated with functionally univentricular hearts, and only few cases have been described so far. Here, we describe the anatomical characteristics of CAT associated with a univentricular heart diagnosed in children and fetuses referred to our institution, and we completed the anatomical description of this rare condition through an extensive review of the literature. The complete cohort ultimately gathered 32 cases described in the literature completed by seven cases from our unit (seven fetuses and one child). Four types of univentricular hearts associated with CAT were observed: tricuspid atresia or hypoplastic right ventricle in 16 cases, mitral atresia or hypoplastic left ventricle in 12 cases, double-inlet left ventricle in 2 cases, and unbalanced atrioventricular septal defect in 9 cases. Our study questions the diagnosis of CAT as the exclusive consequence of an anomaly of the wedging process, following the convergence between the embryonic atrioventricular canal and the common outflow tract. We confirm that some forms of CAT can be considered to be due to an arrest of cardiac development at the stages preceding the convergence.

Staged Repair of Truncus Arteriosus Associated with Complete Atrioventricular Septal Defect

We report a case of successful repair of truncus arteriosus (TA) associated with complete atrioventricular septal defect (c-AVSD) using a staged approach. TA associated with c-AVSD is a very rare congenital cardiac anomaly. No report of successful staged repair in South Korea has yet been published. We performed bilateral pulmonary artery banding when the patient was 33 days old, and total correction using an extracardiac conduit was performed at the age of 18 months. The patient recovered uneventfully and is doing well.

Palliation of Truncus Arteriosus Associated With Complete Atrioventricular Canal--Results of Single Ventricle Palliation

BACKGROUND

Truncus arteriosus associated with complete atrioventricular canal defect is rare and continues to be a surgical challenge with high morbidity and mortality. In the absence of extension of the ventricular septal defect to the outlet septum, biventricular repair is precluded, and single ventricle palliation remains the only option. We present our experience with five patients with truncus arteriosus and complete atrioventricular canal defect who underwent single ventricular palliation.

METHODS

Five patients with truncus arteriosus and complete atrioventricular canal defect managed along the single ventricle palliation pathway were retrospectively reviewed. Demographic, echocardiographic, cardiac catheterization, and perioperative data were analyzed.

RESULTS

All patients underwent neonatal palliation tailored to their anatomy (excision of pulmonary arteries from the common trunk and systemic to pulmonary artery shunt in two patients, excision of pulmonary artery and right ventricle to pulmonary artery conduit in two patients, and bilateral branch pulmonary artery bands in one patient). There were two early deaths after neonatal palliation. At a median follow-up of 210 days (interquartile range 1,210 days), all three survivors have undergone second-stage palliation. Of these patients, one is interstage II to III, and two patients have completed their Fontan procedure and are doing well.

CONCLUSION

Truncus arteriosus with complete atrioventricular canal defect is a rare combination of defects. Single ventricle palliation pathway with a tailored neonatal approach may be employed for patients with uncommitted ventricular septal defects.

Anatomy of common atrioventricular junction with complex associated lesions

The essence of the lesion increasingly described as atrioventricular septal defect is the presence of a common atrioventricular junction. In most instances, the common junction is itself shared in more or less equal fashion between the cardiac chambers, producing the so-called balanced arrangement, which can be considered the default option. Complexity can be produced at various levels within this standard lesion. The most complex malformations are seen in the setting of visceral heterotaxy. Greatest complexity is seen with right isomerism. This always includes totally anomalous pulmonary venous connection, even when the pulmonary veins return to the heart. Still further complexity is often added by the presence of pulmonary stenosis or atresia. Imbalance can involve either the atrial or ventricular chambers. Imbalance at atrial level produces one form of double outlet atrium, but typically with balanced ventricles. Ventricular imbalance represents spectrums extending either to double inlet left or right ventricle through a common atrioventricular valve. Complexity at the level of the ventriculoarterial junctions is seen in the form of abnormal ventriculoarterial connections, notably tetralogy of Fallot or double outlet right ventricle. In these settings, the superior bridging leaflet is free-floating. Hypoplasia of the left atrioventricular valve is part of right ventricular dominance and is often associated with the so-called parachute malformation. Dual orifice is also a problem. In both these lesions, the zone of apposition between the bridging leaflets is the effective inlet to the left ventricle.

Truncus arteriosus and unbalanced complete atrioventricular septal defect: pulmonary protection in the neonate

Surgical success for the combination of truncus arteriosus with unbalanced atrioventricular septal defect is limited. A low incidence and a poor understanding of these lesions, along with a dismal outcome, have made comfort care a common option. We report our experience with initial successful palliation of this combined lesion in two patients.