Faculty Bibliography

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.

Connection of the right pulmonary veins to the azygous is an extremely rare variant of partial anomalous pulmonary venous connection. We describe one such case in the setting of an intact atrial septum. Surgical correction in such a situation can be challenging. We describe a successful surgical approach for this unusual variant.

OBJECTIVES:This study sought to determine the feasibility and safety of unzipping small-diameter stents (SDS) in a growing animal model. BACKGROUND:SDS implanted to relieve stenosis of blood vessels in infants may result in refractory stenosis as the child grows. If stents can be longitudinally fractured-unzipped-then the target vessel can potentially be redilated to the eventual adult vessel diameter. METHODS:Fifty stents (diameter 4 to 7 mm) were implanted in 5 neonatal piglets (mean age and weight = 1.5 weeks and 3.4 kg). Pre-mounted coronary (CS) (n = 24), biliary (BS) (n = 14), nitinol (NS) (n = 3), and renal stents (RS) (n = 9) were implanted in pulmonary arteries (n = 13), systemic arteries (n = 25), and systemic veins (n = 12). Three months later (median weight = 32 kg), unzipping was attempted by dilating the stents. RESULTS:All CS and RS unzipped at twice their nominal diameter with <20% shortening. None of the NS unzipped. The BS shortened the most (∼40%), with only 69% of the stents unzipping. Stainless steel CS and RS with an open cell design were significant predictors (p ≤ 0.01) for unzipping. On histopathology, unzipping of the BS caused the most medial dissection and vessel wall injury, while unzipping of the CS caused the least. CONCLUSIONS:Unzipping of small-diameter CS and RS implanted in systemic and pulmonary vessels is more feasible than the BS and NS. This study may encourage the implantation of small stents in infant blood vessels and aid in selection of appropriate stent type.

Common pulmonary vein atresia is a rare and usually fatal congenital anomaly, in which the pulmonary veins come together to form a confluence that does not connect to the left atrium. We report our experience with three cases of common pulmonary vein atresia and review the literature on this anomaly. The diagnosis of common pulmonary vein atresia must be entertained in any newborn that presents with cyanosis, refractory acidosis, and decreased systemic perfusion within the first 48 hours of life. Echocardiography is a useful screening tool, but cardiac catheterisation is the preferred diagnostic tool. Common pulmonary vein atresia can be fatal without surgical intervention, but survival after surgery continues to be poor.

BACKGROUND:Prolonged pleural effusion following Fontan operation is common and increases morbidity and hospital length of stay. Vasopressin (VP), a neurohypophysial hormone, has numerous effects on the cardiovascular system. The most notable is increased peripheral vascular resistance, but it may also reduce capillary leakage by tightening endothelial intercellular junctions and reducing capillary hydrostatic pressure We reviewed our experience with the perioperative administration of VP following Fontan operation. METHODS:We retrospectively reviewed the records of 62 consecutive patients who underwent Fontan operation from January 2004 to June 2014. In January 2010, VP was introduced as part of the standard perioperative management of patients undergoing Fontan operation at our center. For this retrospective observational study, patients were grouped according to the use (VP; N = 40) or nonuse (non-VP; N = 22) of VP (0.3-0.5 mU/kg/min) in the perioperative period. The primary end point analyzed was chest tube output. Secondary end points analyzed included fluid balance and length of hospital stay, with groups compared using Mann-Whitney U test. RESULTS:There was no hospital mortality. Median total chest tube output was 22 mL/kg in the VP group and 68 mL/kg in the non-VP group (P < .001). The median total duration of chest tube indwelling time was five days in the VP group and was 11 days in the non-VP group (P < .001). Median fluid balance on first postoperative day was 13 and 38 mL/kg, respectively (P < .001). Median hospital stay for VP and non-VP groups was 9 and 16 days, respectively (P = .002). CONCLUSIONS:The more recent group of patients undergoing Fontan operations, all of whom received VP perioperatively, had less chest tube output and shorter duration of chest tube drainage after the Fontan operation relative to the earlier patient group whose perioperative management did not include VP. They also experienced less positive fluid balance in the early postoperative period and shorter hospital length of stay than the patients from the earlier era.