Faculty Bibliography

BACKGROUND:There are no reliable markers to assess brain injury in neonates following cardiac surgery. We examine ubiquitin C-terminal hydrolase 1 (UCHL1) and phosphorylated axonal neurofilament heavy chain (pNF-H), neuronal-specific biomarkers released following axonal and cortical injury, in neonates undergoing cardiac surgery involving cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). METHODS:Twenty-six patients younger than three months were prospectively enrolled (CPB only, n = 12 and DHCA, n = 14). Healthy newborns (n = 22) served as the control. Blood samples were collected preoperatively and postoperatively upon intensive care unit admission (hour 0) and subsequently at 12, 24, 36, and 48 hours. Serum was tested for UCHL1 and pNF-H using enzyme-linked immunosorbent assay. Concomitant arterial blood gas, lactate, and cerebral near-infrared spectroscopy (NIRS) monitoring were performed. RESULTS:Ubiquitin C-terminal hydrolase 1 showed a significant rise at 0 hours in the DHCA group compared to baseline (74.9 ± 13.7 pg/mL vs 33.9 ± 37.3 pg/mL, P < .0001). Levels returned to baseline at 12 hours. There was an early rise in UCHL1 at 0 hours in the CPB group, P = .09. Phosphorylated axonal neurofilament heavy chain was decreased at 0 hours in both the CPB and DHCA groups compared to baseline, P = .06. There was no difference between control and baseline levels of UCHL1 ( P = .9) or pNF-H ( P = .77). Decreased NIRS was observed in the DHCA group at 0 hours (57.3 ± 10.5) versus baseline (64.2 ± 12.3), but not significant ( P = .21). There was no correlation between biomarkers and NIRS at 0 hours. CONCLUSION/CONCLUSIONS:A rapid rise in UCHL1 levels was observed in the DHCA group, suggesting that it may be a marker for acute brain injury. Follow-up with neurodevelopmental studies is ongoing.

Rapid prototyping may be beneficial in properly selected cases of complex congenital heart disease, providing detailed anatomical understanding that helps to guide potential surgical and cardiac catheterization interventions. We present a case of double-outlet right ventricle, where the decision to obtain a three-dimensional printed model helped for better understanding of the anatomy, with the additional advantage of surgical simulation in planning the surgical approach and type of surgical repair.

BACKGROUND: It is still thought by some that a common wall is to be found in the normal heart between the attachments of the caval and pulmonary veins, with absence of this wall underscoring the presence of sinus venosus defects. Recent findings using episcopic microscopy in developing mice have shown the deficiencies of this notion. Understanding that the superior rim of the oval fossa is a fold, rather than a true septum, which can be distorted in the presence of partially anomalous pulmonary venous drainage, has provided an alternative explanation for the morphogenesis of sinus venosus defects. METHODS: We reviewed our experience with patients suspected of having a sinus venosus defect from August, 2011, through October, 2015, analysing the findings in light of the current hypotheses used to explain the development of the defects, along with correlations made by inspection of autopsy specimens. RESULTS: We evaluated findings from 16 patients, with a mean age of 7.7 years, ranging from 2.7 to 15 years. Of the group, 13 were ultimately diagnosed with a superior sinus venosus defect, two with an inferior defect, and one with isolated anomalous pulmonary venous connection in the absence of an interatrial communication. Initially, two patients were thought to have oval fossa defects, one from each subtype, but were correctly diagnosed following cardiac magnetic resonance interrogation. Anomalous pulmonary venous connections were present in all cases. CONCLUSION: Appreciation of the changes occurring during normal cardiac development helps in understanding the anatomical substrate underscoring the spectrum of sinus venosus defects. The lesions are veno-venous connections due to partially anomalous pulmonary venous connections, producing interatrial communications outside the confines of the interatrial septum.

BACKGROUND:Repair of complete atrioventricular canal (CAVC) with tetralogy of Fallot (TOF) is a challenging operation increasingly being performed as a complete, primary repair in infancy. Previous studies have focused on perioperative outcomes; however, midterm valve function, ventricular function, and residual obstruction have received little attention. METHODS:We retrospectively reviewed 20 patients who underwent CAVC/TOF repair (January 2005 to December 2014). A two-patch repair was used in all patients to correct the CAVC defect. Tetralogy of Fallot repair included transannular patch in 11 (65%) patients and valve-sparing in 6 (35%) patients. RESULTS:The average age at surgery was 72 ± 122 weeks, 40% were male, and 80% had trisomy 21. Mean echo follow-up was 3.0 ± 3.0 years. There were no in-hospital or late mortalities. The rate of reoperation was 20%. At the latest follow-up, moderate left atrioventricular valve regurgitation was present in three (15%) patients and mild stenosis present in seven (35%) patients. One (5%) patient had moderate right ventricular outflow tract (RVOT) obstruction. The valve-sparing population was smaller at the time of surgery than the non-valve-sparing cohort (body surface area: 0.28 ± 0.04 vs 0.42 ± 0.11, P = .002) and less likely to have had a previous shunt (0% vs 64%, P = .01). Among the valve-sparing patients (six), at the latest follow-up, moderate pulmonary insufficiency was present in two (33%) patients. CONCLUSION/CONCLUSIONS:Repair of CAVC concomitant with TOF can be performed with low mortality and acceptable perioperative morbidity. Management of the RVOT remains a challenge for the long term.

Rapid prototyping is quickly gaining utility in various complex forms of CHD. In properly selected cases, these printed models provide detailed anatomical understanding that help guide potential surgical and cardiac catheterisation interventions. We present a case of a tunnel-like ventricular septal defect referred for surgical repair, where the decision to obtain a three-dimensional printed model helped in better understanding of the anatomy, leading to delaying, and hopefully avoiding altogether, surgical repair.