Faculty Bibliography

BACKGROUND:The porcine small intestinal extracellular matrix reportedly has the potential to differentiate into viable myocardial cells. When used in tetralogy of Fallot repair, it may improve right ventricular function. We evaluated right ventricular function after repair of tetralogy of Fallot with extracellular matrix versus bovine pericardium. METHOD/METHODS:Subjects with non-transannular repair of tetralogy of Fallot with at least 1 year of follow-up were selected. The extracellular matrix and bovine pericardium groups were compared. We used three-dimensional right ventricular ejection fraction, right ventricle global longitudinal strain, and tricuspid annular plane systolic excursion to assess right ventricular function. RESULTS:The extracellular matrix group had 11 patients, whereas the bovine pericardium group had 10 patients. No differences between the groups were found regarding sex ratio, age at surgery, and cardiopulmonary bypass time. The follow-up period was 28±12.6 months in the extracellular matrix group and 50.05±17.6 months in the bovine pericardium group (p=0.001). The mean three-dimensional right ventricular ejection fraction (55.7±5.0% versus 55.3±5.2%, p=0.73), right ventricular global longitudinal strain (-18.5±3.0% versus -18.0±2.2%, p=0.44), and tricuspid annular plane systolic excursions (1.59±0.16 versus 1.59±0.2, p=0.93) were similar in the extracellular matrix group and in the bovine pericardium group, respectively. Right ventricular global longitudinal strain in healthy children is reported at -29±3% in literature. CONCLUSION/CONCLUSIONS:In a small cohort of the patients undergoing non-transannular repair of tetralogy of Fallot, there was no significant difference in right ventricular function between groups having extracellular matrix versus bovine pericardium patches followed-up for more than 1 year. Lower right ventricular longitudinal strain noted in both the groups compared to healthy children.

OBJECTIVES/OBJECTIVE:The primary objective of this study was to demonstrate that pulmonary artery (PA) debanding via cardiac catheterization using balloon angioplasty is feasible and safe in swine. The secondary objectives were to determine the acute and long-term effects of this therapy. DESIGN/METHODS:This is a chronic survival experimental study in newborn swine. BACKGROUND:PA bands are used in infants for transient palliation of congenital heart defects with excessive pulmonary blood flow. Although rare, if these defects should close spontaneously or become hemodynamically insignificant, a sternotomy and occasionally cardiopulmonary bypass may still be required for band removal. Alternatively, debanding could be accomplished through less invasive methods. INTERVENTIONS/METHODS:The main pulmonary artery was banded in three piglets, and the left pulmonary artery in five piglets via mini-thoracotomy at a mean weight of 2.5 kg. Following a threefold increase in weight, the piglets underwent PA debanding via balloon angioplasty. Four piglets were sacrificed to evaluate the acute effects. The remainder were followed to evaluate long-term effects. Histopathology was performed on all piglets. OUTCOME MEASURES/METHODS:Reintervention rates. Histopathologic consequences of high pressure balloon angioplasty used for PA debanding acutely and after reinterventions. RESULTS:Debanding was performed at a mean weight of 8.1 ± 2.23 kg. The median preintervention gradient across the band was 18 mm Hg. Debanding was successful in all piglets. The median postintervention gradient was 3.5 mm Hg. All piglets in the long-term model required re-interventions for recurrent stenosis at mean weights of 26 ± 1.6 and 61 ± 3.2 kg. Histopathology demonstrated vessel wall injury in only one piglet. CONCLUSIONS:Endovascular PA debanding can be safely achieved in a swine model. Angioplasty following debanding may be necessary for recurrent stenosis. This catheter-based therapy may provide a less-invasive alternative to surgery.

Left thoracic sympathectomy has been shown to be an effective treatment for adults with long QT syndrome who are refractory to medical therapy. We report the successful use of left thoracic sympathectomy for the management of a 10-week-old premature baby with long QT syndrome and heart failure from a large ventricular septal defect and patent ductus arteriosus.

Neonatal arterial switch operation for simple dextro-transposition of the great arteries (d-TGA) has almost eliminated the occurrence of pulmonary vascular obstructive disease compared to patients who underwent Mustard or Senning procedure at an older age. We report a case of a neonate with d-TGA and intact ventricular septum who underwent arterial switch operation and yet developed severe pulmonary vascular obstructive disease within two months.

Interest in peptides as diagnostic and therapeutic materials require their manufacture via either a recombinant or synthetic route. This study examined the former, where a recombinant fusion consisting of an antifungal peptide was expressed and isolated from Escherichia coli. Fed batch fermentation with E. coli harboring an arabinose-inducible plasmid produced the 12 residue anti-Candida peptide fused to the N-terminal of Green Fluorescent Protein (GFPUV ). The purification of the fusion protein, using ion-exchange chromatography, was monitored by using the intrinsic fluorescence of GFPUV . The recombinant antifungal peptide was successfully released by cyanogen bromide-induced cleavage of the fusion protein. The recombinant peptide showed the expected antifungal activity. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:865-871, 2016.

We report a case of an infant who was postnatally diagnosed with hypoplastic left heart syndrome and an intact atrial septum who underwent emergent atrial decompression followed by the Norwood operation. She was also found to have a congenital diaphragmatic hernia on the left side and a congenital eventration of the right diaphragm, both requiring surgical repair. She was later found to have an anomalous origin of the left circumflex coronary artery from the right pulmonary artery that was ligated at the time of the bilateral bidirectional Glenn operation. She is currently thriving at home, defying all odds.

Experience with pericardial bioprostheses in young patients is limited. Accelerated degeneration of the Mitroflow valve has recently been reported. We report early accelerated structural valve degeneration with the Perimount Magna bioprosthesis, which has not been previously reported. Young patients with the Magna bioprosthesis are at high risk for rapid progression to severe stenosis, which underscores their need for more vigilant surveillance. The benefits and risks of these bioprosthetic valves must be weighed carefully when options for replacement in these young patients are discussed.

OBJECTIVES:To review the management and outcomes of pediatric patients treated for descending mediastinitis at a single institution and contribute to an updated mortality rate. STUDY DESIGN:Case series with chart review. SETTING:Tertiary care pediatric hospital. SUBJECTS AND METHODS:This study is a 19-patient case series of all patients treated for descending mediastinitis at a tertiary pediatric hospital from 1997 to 2015, and it serves as an update to the case series published from this institution in 2008. Review of management included time to diagnosis, time to surgery, surgical procedures performed, and antibiotics administered. The primary outcomes measured were length of hospitalization and mortality. RESULTS:In addition to 8 previously reported patients, we identified 11 pediatric patients treated for descending mediastinitis in the period of review. All 19 patients were <18 months old, and all survived their hospitalization. Fourteen patients underwent surgical drainage at least twice. The median length of hospital stay was 15 days. Retropharyngeal abscess was the source of infection in 16 of 19 patients, and methicillin-resistant Staphylococcus aureus (MRSA) was the isolated organism in 14 of 15 positive cultures. CONCLUSION:This review represents the largest reported series of pediatric patients with descending mediastinitis. With 100% survival, our results suggest that pediatric descending mediastinitis can be safely managed by prompt surgical drainage. Broad-spectrum antibiotics covering MRSA and a low threshold for repeat surgical intervention have been an important part of our successful approach and may decrease length of stay.

OBJECTIVE:Acute kidney injury (AKI) following cardiac surgery is a serious complication with a reported incidence of 30% to 50%. This study sought to determine the prevalence and risk factors for AKI among neonates and young infants undergoing repair of cardiac defects at an institution using novel perioperative strategies. METHODS:A retrospective analysis of 102 consecutive infants (<2 months) undergoing repair of cardiac defects on cardiopulmonary bypass formed the study group. Cardiac diagnoses were stratified according to the Society of Thoracic Surgeons Congenital Heart Surgery (STAT) mortality categories. The prevalence of AKI within 72 hours was defined according to the three-stage Acute Kidney Injury Network criteria. Novel bypass strategies to preserve renal function included maintenance of higher hematocrit and high flow rates on cardiopulmonary bypass despite systemic hypothermia, and avoidance of albumin and milrinone in the perioperative period. RESULTS:Mean age was 24 ± 19 days. Eighteen patients were less than 7 days of age at the time of surgery. Patient distribution according to STAT categories was as follows: 1 (n = 21), 2 (n = 12), 3 (n = 22), 4 (n = 28), and 5 (n = 19). The incidence of stages 1, 2, and 3 AKI in the population was 8% (n = 9), 2% (n = 2), and 0% (n = 0), respectively. On multivariate analysis higher STAT category was the only significant risk factor for AKI. CONCLUSION/CONCLUSIONS:Current incidence of AKI following cardiac surgery in young infants at our institution is low. Novel perioperative strategies may have contributed to the low observed incidence of AKI in our patient population. Increased complexity of heart disease was a risk factor for AKI.