Recurrent Pulmonary Artery Interventions Following the Norwood Procedure Are Not Associated With Conduit Type.

Given pulmonary artery interventions following the Norwood procedure can recur, the average number of occurrences per patient over time is likely more informative than the crude percentage of patients who required an intervention. Pulmonary artery intervention was defined as any surgical or catheter-based procedure after the Norwood procedure. The number of pulmonary artery interventions for patients with hypoplastic left heart syndrome were compared between patients with modified Blalock-Taussig Shunts (MBTS) and right ventricle-to-pulmonary artery conduits (RVPA) at a single institution from 2011 to 2018. The comparison was replicated using data from the Single Ventricle Reconstruction Trial (SVR), a nonoverlapping dataset. The mean number of pulmonary artery interventions per patient over time (mean cumulative function, MCF) is described using Nelson-Aalen estimates and compared using the pseudo-score test. The number of patients requiring intervention was compared using the chi-square test. Using our institutional dataset, the Norwood operation was performed on 117 patients (59 MBTS, 58 RVPA). In total, 73 patients had a pulmonary artery intervention, including 32 of 58 (55%) after MBTS and 41 of 59 (69%) after RVPA (P= 0.11). The MCF did not vary between cohorts (P = 0.55). Using the SVR trial dataset, 140 of 549 patients required pulmonary artery intervention, including 55 (21%) after MBTS and 85 (30%) after RVPA (P = 0.0090). The MCF did not vary between cohorts (P = 0.067). Although more patients with RVPA than MBTS require pulmonary artery interventions after the Norwood procedure, the MCFs are not different, which may be of greater importance to patients and families.

Bronchial artery revascularization and en bloc lung transplant in children.

BACKGROUND: Long-term success in pediatric lung transplantation is limited by infection and bronchiolitis obliterans syndrome (BOS). The bilateral sequential lung transplantation (BSLT) technique may result in airway ischemia leading to bronchial stenosis, dehiscence, or loss of small airways. En bloc lung transplant (EBLT) with bronchial artery revascularization (BAR) minimizes airway ischemia, thus promoting superior airway healing. BAR also allows for safe tracheal anastomosis, circumventing the need for bilateral bronchial anastomoses in small children. METHODS: This was a retrospective review of bilateral transplantations from 2005 to 2014. Both techniques were used in parallel. Redo and multiorgan transplants were excluded. RESULTS: There were 119 recipients comprising 88 BSLTs and 31 EBLTs. Follow-up time was 3 years (interquartile range, 1-5 years). Donor ischemic and cardiopulmonary bypass times were not different between techniques (p = 0.48 and p = 0.18, respectively). Degree of graft dysfunction and cellular rejection scores were not different (p = 0.83 and p = 0.93, respectively). There were 3 hospital deaths after BSLT and 2 after EBLT (p = 0.60). Overall survival was 61% for the BSLT group and 77% for the EBLT group (p = 0.54). Freedom from BOS was 71% in the BSLT group and 94% in the EBLT group (p = 0.08). On routine bronchoscopy, 57% BSLT and 16% EBLT patients had 1 or more airway ischemic findings (p < 0.0001). Multivariate analysis showed BSLT was associated with higher ischemic injury (relative risk, 2.86; 95 confidence interval, 1.3-6.5; p = 0.01) and non-airway complications (relative risk, 4.62; 95% confidence interval, 1.1-20.2; p = 0.04) but not airway reinterventions (p = 0.07). Airway dehiscence occurred in 3 BSLT patients. CONCLUSIONS: Pediatric EBLT with BAR can be safely performed without increasing operative or graft ischemic times. Airway ischemia and non-airway complications were significantly reduced when BAR was combined with tracheal anastomosis, potentially diminishing morbidity caused by anastomotic healing complications.

Impact of preoperative risk factors on outcomes after Norwood palliation for hypoplastic left heart syndrome.

BACKGROUND: Infants with hypoplastic left heart syndrome (HLHS) are susceptible to pre-Norwood comorbidities (PCs) and complications. This study aimed to describe the effect of PCs on timing and survival of Norwood palliation (NP). METHODS: A single-center, retrospective review of infants with HLHS who underwent initial NP between 2003 and 2010 was performed. PCs included intact atrial septum, ≥ moderate atrioventricular regurgitation (AVVR), no antenatal diagnosis, mitral stenosis/aortic atresia subtype, genetic abnormality, and prematurity. Complications included pre-NP mechanical ventilation, inotropic support, infection, arrhythmia, and end-organ injury. The primary outcome measure was survival after NP. RESULTS: 113 patients were included with 78 (69%) patients having at least one PC and 61 (78%) of those patients having at least one complication. Patients with PCs underwent NP later than those without PCs (7 vs 6 days, P = .036) as well as when associated with a complication (8 vs 5 days, P < .001). Patients with PCs had similar post-Norwood hospital length of stay (P = .116) except when the PC occurred in conjunction with a complication (28 vs 21 days; P = .015). In-hospital mortality post-NP was 10% and interstage mortality was 15%. On multivariable analysis, ≥ moderate AVVR was associated with increased overall mortality (OR 2.8, 95% CI 1.3-6.2). Age at NP was not associated with mortality (P = .638). CONCLUSIONS: Although PCs are common in infants with HLHS, only ≥ moderate AVVR was associated with increased mortality in this single-center experience. Older age at NP was not a significant risk factor for interstage mortality.

Erythropoietin neuroprotection in neonatal cardiac surgery: a phase I/II safety and efficacy trial.

OBJECTIVES: Neonates undergoing complex congenital heart surgery have a significant incidence of neurologic problems. Erythropoietin has antiapoptotic, antiexcitatory, and anti-inflammatory properties to prevent neuronal cell death in animal models, and improves neurodevelopmental outcomes in full-term neonates with hypoxic ischemic encephalopathy. We designed a prospective phase I/II trial of erythropoietin neuroprotection in neonatal cardiac surgery to assess safety and indicate efficacy. METHODS: Neonates undergoing surgery for D-transposition of the great vessels, hypoplastic left heart syndrome, or aortic arch reconstruction were randomized to 3 perioperative doses of erythropoietin or placebo. Neurodevelopmental testing using the Bayley Scales of Infant and Toddler Development III was performed at age 12 months. RESULTS: Fifty-nine patients received the study drug. Safety profile, including magnetic resonance imaging brain injury, clinical events, and death, was not different between groups. Three patients in each group died. Forty-two patients (22 in the erythropoietin group and 20 in the placebo group; 79% of survivors) returned for 12-month follow-up. In the group receiving erythropoietin, mean Cognitive Scale scores were 101.1 ± 13.6, Language Scale scores were 88.5 ± 12.8, and Motor Scale scores were 89.9 ± 12.3. In the group receiving placebo, Cognitive Scale scores were 106.3 ± 10.8 (P = .19), Language Scores were 92.4 ± 12.4 (P = .33), and Motor Scale scores were 92.6 ± 14.1 (P = .51). CONCLUSIONS: Safety profile for erythropoietin administration was not different than placebo. Neurodevelopmental outcomes were not different between groups; however, this pilot study was not powered to definitively address this outcome. Lessons learned suggest optimized study design features for a larger prospective trial to definitively address the utility of erythropoietin for neuroprotection in this population.

Type B interrupted left aortic arch with isolated right subclavian artery.

Interrupted aortic arch is a rare congenital heart malformation occurring in approximately three per 1 million births. Type B interrupted aortic arch (interruption between the second carotid artery and the ipsilateral subclavian artery) is the most common of three major types (A, B, and C). We report an extremely rare finding: a case of left-sided type B interrupted aortic arch with isolation of the right subclavian artery (origin from the right pulmonary artery).

Repeat sternotomy in congenital heart surgery: no longer a risk factor.

BACKGROUND: The risk of repeat sternotomy (RS) is often taken into account when making clinical management decisions. Current literature on RS suggests a risk of approximately 5% to 10% for major morbidity. We sought to establish the true risk of RS in a contemporary pediatric series. METHODS: All RS between October 2002 and August 2006 were analyzed (602 RS in 558 patients). Median age was 3.6 years (range, 0.1 to 45.1); weight, 14.2 kg (2.0 to 112.2). Operations performed at RS were Glenn 22% (131), Fontan 21% (129), aortic valve repair/replacement 12% (72), right ventricle-pulmonary artery conduit 11% (67), Rastelli 7% (39), heart transplant 5% (31), and other 22% (133). Forty-seven percent of patients (280) had single-ventricle physiology. Incidence of second sternotomy was 67% (406), third 28% (166), fourth 4% (24), fifth 0.8% (5), and sixth 0.2% (1). A major injury upon RS was defined as one causing hemodynamic instability requiring vasopressor support or emergent transfusion; femoral cannulation or emergent cardiopulmonary bypass; and any morbidity. A minor injury is any other injury during RS. RESULTS: The incidence of a major injury was not different between RS (0.3%; 2 of 602) and first-time sternotomy (0%; 0 of 1,274; p > 0.1). Incidence of a minor injury was 0.66% (4 of 602). No injury resulted in hemodynamic instability, neurologic injury, or death. Two patients (0.3%) required a nonemergent blood transfusion secondary to injury. (Nonemergent was defined as adminstration rate of less than 0.2 cc/kg/min and less than 10 cc/kg in total.) Femoral cannulation was performed in 4 of 602 RS cases (< 0.6%). Sternal wound infection was 0.5% (3 of 602); reoperation for postoperative bleeding was 1% (8 of 602). Median intensive care unit stay was 3 days (1 to 174); median hospital stay was 7 days (1 to 202). Hospital survival was 98%. CONCLUSIONS: Repeat sternotomy can represent a negligible risk of injury and of subsequent morbidity or mortality. Therefore, the choice of management strategies for patients should not be affected by the need for RS.

Pediatric lung transplantation: a therapy in its adolescence.

Pediatric lung transplant was born at the University of Toronto as an extension of the pioneering work of Cooper and Patterson in adult lung transplant in the 1980s. Through the 1990s, the field of pediatric lung transplantation grew with clinical outcomes in the largest centers being comparable to those in adult lung transplantation. For children and adults, the largest obstacle to long-term survival remains chronic allograft rejection secondary to the development of bronchiolitis obliterans, for which little advancement has been made in prevention or treatment. While transplantation has become accepted therapy for end-stage lung disease in adults, pediatric lung transplant has been less widely embraced for multiple reasons, such as adolescent non-compliance and the investment required in developing freestanding pediatric lung transplant centers. Another factor limiting pediatric lung transplant has been the paucity of suitable donor lungs. In 2002, Texas Children's Hospital and the Baylor College of Medicine successfully collaborated in developing an active and successful pediatric lung transplant program. Through our own work and an international collaborative of pediatric transplant pulmonologists and surgeons, we are hoping to move the field of pediatric lung transplant out of its "adolescence" into adulthood.

Anatomic reconstruction for recurrent aortic obstruction in infants and children.

BACKGROUND: Patients undergoing operative repair of aortic obstruction are at a lifelong risk of recurrent obstruction, and there is controversy regarding the optimal surgical technique. We have used an alternative strategy for recurrent aortic obstruction, typically involving anatomic reconstruction by means of a median sternotomy, and describe our techniques and results. METHODS: Twenty-one patients presented with recurrent aortic arch obstruction. Mean age and weight were 7.8 +/- 5.4 years (range, 0.21 to 15.2 years) and 30.6 +/- 21.8 kg (range, 3.6 to 90 kg), respectively. Recurrence involved the aortic arch to some degree in each case, as the mean preoperative transverse aortic arch z score was -2.9 +/- 1.6 (range, -7.0 to 0.1). Thoracotomy was possible in 2 patients, using re-resection with end-to-end anastomosis (n = 1) and patch aortoplasty (n = 1). The remaining 19 patients required median sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest for complete relief of obstruction by aortic arch advancement (n = 10), patch aortoplasty (n = 8), or interposition grafting (n = 1). RESULTS: There was 1 hospital death. Invasive blood pressure monitoring revealed no residual arm-to-leg gradient in 19 patients and a 20-mm Hg gradient in 2 patients. There have been no late deaths. No patients have undergone subsequent aortic intervention, and all are asymptomatic up to 85 months postoperatively. Two patients are currently followed with a 10-mm Hg arm-to-leg blood pressure gradient. CONCLUSIONS: Anatomic reconstruction for recurrent aortic obstruction can be safely accomplished in the majority of patients. We favor median sternotomy because of the ability of establishing cardiopulmonary bypass, the facility of anatomic reconstruction techniques, and the ability to repair concomitant cardiovascular lesions.