Conal Septal Hypoplasia in Tetralogy of Fallot-Impact on Clinical Course, Treatment Strategies, and Outcomes After Surgical Intervention.

We sought to characterize the clinical course and outcomes of intervention for Tetralogy of Fallot (TOF) with associated conal septal hypoplasia (CSH) compared to those with identifiable conal septum on initial newborn echocardiogram. We performed a retrospective, 1:2 case-control study of children with TOF anatomy, 33 with CSH and 66 with typical TOF, who underwent surgical repair from 1991-2019 at Children's Wisconsin. Data on echocardiographic anatomic features, systemic oxygen saturations, medical therapies, admissions, palliative interventions, operative strategies, and long-term follow-up were compared. The CSH group had fewer hypercyanotic spells (6% vs 42%, p < 0.001), beta-blockers prescribed (12% vs 41%, p = 0.005), and hospital admissions for cyanosis (12% vs 44%; p = 0.001) prior to any intervention. Of 14 who required palliative intervention, 8 had balloon pulmonary valvuloplasty (BPV) (7 from the CSH group and 1 from the control group), and 6 had systemic-to-pulmonary artery shunts (all from the control group). Definitive repair was performed at a significantly older age in the CSH group (10.2 ± 10 vs 5.6 ± 5.9 months, p = 0.011), with less subpulmonary muscle resection (57.6% in vs 92.4%, p < 0.001) and higher use of a transannular patch (84.8% vs 65.2%, p = 0.040). The average time to surgical reintervention was similar in both groups (9.7 ± 5.9 vs 8.6 ± 6.4 years in controls). We conclude that infants with TOF and CSH have a milder preoperative clinical course with fewer hypercyanotic spells or need for medical therapy. They also respond well to palliative BPV and can safely undergo later definitive repair compared to typical TOF with a well-developed conal septum.

Intermediate Outcomes of Staged Tetralogy of Fallot Repair.

BACKGROUND: The optimal surgical strategy for tetralogy of Fallot (TOF) repair in neonates and young infants requiring early surgical intervention remains controversial. Our surgical center follows the uniform strategy of a staged approach with initial systemic-to-pulmonary artery shunt the majority of time when early surgical intervention is required. We characterized a contemporary cohort of patients with TOF with pulmonary stenosis (PS) undergoing staged repair in order to determine the rate of pulmonary valve-sparing repair (PVSR), growth of the pulmonary valve annulus and pulmonary arteries, postoperative morbidity and mortality, and need for reintervention. METHODS: We retrospectively studied patients with TOF/PS who underwent staged repair from 2000 to 2017. Surgical details, postoperative course, and reinterventions were noted. Echocardiographic measurements and Z-score values of pulmonary valve annulus, main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary artery (LPA) diameters were evaluated. RESULTS: Of the 59 patients with staged TOF/PS, PVSR was performed in 25 (42%). There was a 5% incidence of postoperative arrhythmia. The Z-scores of MPA, RPA, and LPA were significantly higher before complete repair when compared to before palliative shunt. The 5 and 10-year survival rates were both 93%, and the probability of freedom from reoperation at 5 and 10 years was 87% and 82%, respectively. CONCLUSIONS: Staged repair of TOF in young symptomatic infants results in 42% receiving PVSR, pulmonary artery growth, low incidence of postoperative arrhythmia, and relatively low rate of reoperations.