Primary surgical repair of tetralogy of Fallot at under three months of age

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.

The Effect of Abnormal Regional Homogeneity and Spontaneous Low-Frequency Brain Activity on Lower Cognitive Ability: A Cross-Sectional Study on Postoperative Children With Tetralogy of Fallot

Despite intracardiac malformation correction, children with Tetralogy of Fallot (TOF) may still suffer from brain injury. This cross-sectional study was primarily designed to determine the relationship between blood oxygenation level-dependent (BOLD) signal changes after surgery and cognition in school-aged children with TOF. To evaluate the differences between TOF children (n = 9) and healthy children (n = 9), resting-state functional magnetic resonance imaging (rs-fMRI) and the Wechsler Intelligence Scale for Children–Chinese revised edition (WISC-CR) were conducted in this study. The results showed that TOF children had a lower full-scale intelligence quotient (FSIQ, 95.444 ± 5.354, p = 0.022) and verbal intelligence quotient (VIQ, 92.444 ± 4.708, p = 0.003) than healthy children (FSIQ = 118.500 ± 4.330;VIQ = 124.250 ± 4.404), and that significant differences in regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF) existed between the two groups. Besides, VIQ had significantly positive correlations with the decreased ALFF value of the middle inferior occipital gyrus (MIOG, beta = 0.908, p = 0.012) after fully adjusting for all covariates. In addition, elevated ReHo values of the left and right precuneus were positively related to ALFF in the MIOG. This study revealed that brain injury substantially influences neural activity and cognition in postoperative TOF children, providing direct evidence of an association between BOLD signal changes and the VIQ and prompting further attention to language development in TOF children.

The Limited Benefit of Follow-Up Echocardiograms After Repair of Tetralogy of Fallot

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease, making up 10% of all congenital heart defects. Annual follow-up echocardiograms are recommended in patients with repaired ToF, but evidence-based guidelines do not exist. We hypothesized that most echocardiograms performed in asymptomatic patients with repaired ToF and no physical exam change do not result in an actionable change (AC) in management. We retrospectively reviewed records of all patients with ToF and prior complete repair at our institution between January 2000 and September 2015. Changes in echocardiograms resulting in hospital admission, medication addition/change, cardiac catheterization, or surgical procedure were identified via chart review. These changes were referred to as an AC. A total of 1135 echocardiograms were reviewed from 233 patients (160 with initial complete repair, 70 with prior shunt, and 3 with other initial surgery). The median number of echocardiograms per patient was 5. Of the 1135 echocardiograms, 15 (1.3%) were associated with AC. Of the 15 patients with AC echocardiograms, 9 underwent a shunt prior to complete repair (9/70, 12.9%) and 6 had undergone an initial complete repair (6/160, 3.8%). The median age at AC was 6.3 years (IQR 4.4, 6.8) in the shunt group and 0.90 years (IQR 0.87, 1.1) in the initial complete repair group. In asymptomatic patients with repaired ToF and no physical exam change, echocardiograms rarely lead to a change in clinical management. In conclusion, the likelihood and timing of AC echocardiograms and reinterventions vary based on the type of initial surgery.