Kim Duncan

Neurodevelopmental Outcomes After Cardiac Surgery in Infancy

BACKGROUND: Neurodevelopmental disability is the most common complication for survivors of surgery for congenital heart disease (CHD). METHODS: We analyzed individual participant data from studies of children evaluated with the Bayley Scales of Infant Development, second edition, after cardiac surgery between 1996 and 2009. The primary outcome was Psychomotor Development Index (PDI), and the secondary outcome was Mental Development Index (MDI). RESULTS: Among 1770 subjects from 22 institutions, assessed at age 14.5 ± 3.7 months, PDIs and MDIs (77.6 ± 18.8 and 88.2 ± 16.7, respectively) were lower than normative means (each P < .001). Later calendar year of birth was associated with an increased proportion of high-risk infants (complexity of CHD and prevalence of genetic/extracardiac anomalies). After adjustment for center and type of CHD, later year of birth was not significantly associated with better PDI or MDI. Risk factors for lower PDI were lower birth weight, white race, and presence of a genetic/extracardiac anomaly (all P ≤ .01). After adjustment for these factors, PDIs improved over time (0.39 points/year, 95% confidence interval 0.01 to 0.78; P = .045). Risk factors for lower MDI were lower birth weight, male gender, less maternal education, and presence of a genetic/extracardiac anomaly (all P < .001). After adjustment for these factors, MDIs improved over time (0.38 points/year, 95% confidence interval 0.05 to 0.71; P = .02). CONCLUSIONS: Early neurodevelopmental outcomes for survivors of cardiac surgery in infancy have improved modestly over time, but only after adjustment for innate patient risk factors. As more high-risk CHD infants undergo cardiac surgery and survive, a growing population will require significant societal resources.

Increased hepatic stiffness as consequence of high hepatic afterload in the fontan circulation: A vascular doppler and elastography study

Hepatic dysfunction is a recognized complication after Fontan palliation of congenital heart disease. We sought to quantitatively measure hepatic stiffness and vascular Doppler indices using ultrasound (US) and shear wave elastography (SWE) in a Fontan cohort. Subjects were prospectively recruited for echocardiography and real‐time hepatic duplex US with SWE for hepatic stiffness (kPa). Doppler peak velocities, velocity time integral, resistive, pulsatility, acceleration indices (RI, PI, AI), and flow volume were measured in celiac artery, superior mesenteric artery, and main portal vein (MPV). A subset underwent cardiac catheterizations with liver biopsy. Correlations were explored between SWE, duplex, hemodynamic, and histopathologic data. In all, 106 subjects were studied including 41 patients with Fontan physiology (age 13.8 ± 6 years, weight 45.4 ± 23 kg) and 65 controls (age 15.0 ± 8.4 years, weight 47.9 ± 22 kg). Patients with Fontan physiology had significantly higher hepatic stiffness (15.6 versus 5.5 kPa, P < 0.0001), higher celiac RI (0.78 versus 0.73, P = 0.04) superior mesenteric artery RI (0.89 versus 0.84, P = 0.005), and celiac PI (1.87 versus 1.6, P = 0.034); while MPV flow volume (287 versus 420 mL/min in controls, P = 0.007) and SMA AI (829 versus 1100, P = 0.002) were lower. Significant correlation was seen for stiffness with ventricular end‐diastolic pressure (P = 0.001) and pulmonary artery wedge pressure (P = 0.009). Greater stiffness correlated with greater degrees of histopathologic fibrosis. No significant change was seen in stiffness or other duplex indices with age, gender, time since Fontan, or ventricular morphology. Conclusion: Elevated hepatic afterload in Fontan, manifested by high ventricular end‐diastolic pressures and pulmonary arterial wedge pressures, is associated with remarkably increased hepatic stiffness, abnormal vascular flow patterns, and fibrotic histologic changes. The MPV is dilated and carries decreased flow volume, while the celiac and superior mesenteric arterial RI is increased. SWE is feasible in this population and shows promise as a means for predicting disease severity on liver biopsy. (Hepatology 2014;58:251–260)

Decade of experience with vascular rings at a single institution

OBJECTIVE. Over the past decade, the diagnostic workup of vascular rings has changed at our institution. Despite surgical intervention, we have observed long-term aerodigestive issues in some patients. In an effort to better characterize these pre- and postoperative issues, we reviewed a decade of experience at our institution. METHODS. We performed a complete chart review of all patients identified as having surgical intervention for vascular ring between January 1993 and December 2003. A questionnaire was mailed to the family of each patient to ascertain a subjective assessment of long-term postoperative issues. RESULTS. Thirty-eight patients were reviewed and categorized as to specific arch anomaly. Associated cardiac anomalies were present in 29% of patients. Chronic feeding difficulties persisted in 18% of patients, and airway issues remained in nearly half of the patients. Patients with underlying genetic syndromes had less resolution of symptoms compared with nonsyndromic children. Chronic respiratory symptoms were present in 80% of patients operated <6 months, 15% if operated between 6 months and 3 years, and 42% of patients operated after 3 years of age. CONCLUSIONS. Aerodigestive issues may persist after vascular ring division despite initial improvement. Accurate preoperative anatomic imaging is imperative to surgical planning.

Impact of operative and postoperative factors on neurodevelopmental outcomes after cardiac operations

BACKGROUND Neurodevelopmental disability is common after operations for congenital heart defects. We previously showed that patient and preoperative factors, center, and calendar year of birth explained less than 30% of the variance for the Psychomotor Development Index (PDI) and the Mental Development Index (MDI) of the Bayley Scales of Infant Development-Second Edition. Here we investigate how much additional variance in PDI and MDI is contributed by operative variables and postoperative events. METHODS We analyzed neurodevelopmental outcomes after operations with cardiopulmonary bypass at age 9 months or younger between 1996 and 2009. We used linear regression to investigate the effect of operative factors (age, weight, and cardiopulmonary bypass variables) and postoperative events on neurodevelopmental outcomes, adjusting for center, type of congenital heart defect, year of birth, and preoperative factors. RESULTS We analyzed 1,770 children from 22 institutions with neurodevelopmental testing at age 13.3 months (range, 6 to 30 months). Among operative factors, longer total support time was associated with lower PDI and MDI (p < 0.05). When postoperative events were added, use of either extracorporeal membrane oxygenation or ventricular assist device support, and longer postoperative length of stay were associated with lower PDI and MDI (p < 0.05). Longer total support time was not a significant predictor in these models. After adjusting for patient, preoperative, intraoperative, and postoperative factors, measured intraoperative and postoperative factors accounted for 5% of the variances in PDI and MDI. CONCLUSIONS Operative factors may be less important than innate patient and preoperative factors and postoperative events in predicting early neurodevelopmental outcomes after cardiac operations in infants. Neurodevelopmental outcomes improved over calendar time when adjusted for patient and medical variables.

Long-term functional health status and exercise test variables for patients with pulmonary atresia with intact ventricular septum: A Congenital Heart Surgeons Society study

BACKGROUND A bias favoring biventricular (BV) repair exists regarding choice of repair pathway for patients with pulmonary atresia with intact ventricular septum (PAIVS). We sought to determine the implications of moving borderline candidates down a BV route in terms of late functional health status (FHS) and exercise capacity (EC). METHODS Between 1987 and 1997, 448 neonates with PAIVS were enrolled in a multi-institutional study. Late EC and FHS were assessed following repair (mean 14 years) using standardized exercise testing and 3 validated FHS instruments. Relationships between FHS, EC, morphology, and 3 end states (ie, BV, univentricular [UV], or 1.5-ventricle repair [1.5V]) were evaluated. RESULTS One hundred two of 271 end state survivors participated (63 BV, 25 UV, and 14 1.5V). Participants had lower FHS scores in domains of physical functioning (P < .001) compared with age- and sex-matched normal controls, but scored significantly higher in nearly all psychosocial domains. EC was higher in 1.5V-repair patients (P = .02), whereas discrete FHS measures were higher in BV-repair patients. Peak oxygen consumption was low across all groups, and was positively correlated with larger initial tricuspid valve z-score (P < .001), with an enhanced effect within the BV-repair group. CONCLUSIONS Late patient-perceived physical FHS and measured EC are reduced, regardless of PAIVS repair pathway, with an important dichotomy whereby patients with PAIVS believe they are doing well despite important physical impediments. For those with smaller initial tricuspid valve z-score, achievement of survival with BV repair may be at a cost of late deficits in exercise capacity, emphasizing that better outcomes may be achieved for borderline patients with a 1.5V- or UV-repair strategy.

Neurodevelopmental Outcomes in Infants after Surgery for Congenital Heart Disease: A Comparison of Single‐Ventricle vs. Two‐Ventricle Physiology

INTRODUCTION The neurodevelopmental outcome of children with repaired congenital heart defect has risen in importance with improved survival. This study compares neurodevelopmental outcomes of children who had CHD with single ventricle physiology with those who had CHD with two-ventricle physiology. PATIENTS AND METHODS Participants included 112 infants discharged from the NICU between February 1999 to August 2006. The 12 infants who had a known genetic defect were excluded. Of the 100 infants 26 had single ventricle physiology and 74 had CHD with two-ventricle physiology. The children were seen in a follow-up clinic and growth parameters and standardized instruments were used to evaluate development. The referral rate to early intervention services was also compared. RESULTS The number of functional ventricles did not significantly differentiate growth parameters at 6-8 months of age. Early cognitive outcomes were relatively unimpaired in both the groups (single ventricle vs. two ventricle physiology). Early motor outcomes were worse in (p < 0.05) CHD with single ventricle physiology. The rate of referral for early intervention services was high in both groups compared to the average rate of referral in the state, but there was not a significant difference between the CHD groups. CONCLUSION Significant differences noted on motor outcomes at the 6-8 month visit were no longer apparent in later visits. Referral to early intervention services is high in both the groups. These findings are important to those caring for infants with CHD because many of these patients may need referral for early intervention.

Combined heart and liver transplantation against positive cross-match for patient with hypoplastic left heart syndrome

21: 2596. 10. Varela-Fascinetto G, Bracho E, Dávila R, et al. En bloc and single kidney transplantation from donors weighing less than 15 kg into pediatric recipients. Transplant Proc 2001; 33: 2034. 11. Laube GF, Kellenberger CJ, Kemper MJ, et al. Transplantation of infant en bloc kidneys into paediatric recipients. Pediatr Nephrol 2006; 21: 408. 12. Lau KK, Berg GM, Schjoneman YG, et al. Pediatric en bloc kidney transplantation into pediatric recipients. Pediatr Transplant 2010; 14: 100. 13. Afanetti M, Niaudet P, Niel O, et al. Pediatric en bloc kidney transplantation into pediatric recipients: the French experience. Pediatr Transplant 2012; 16: 183. 14. Laurence JM, Sandroussi C, Lam VW, et al. Utilization of small pediatric donor kidneys: a decision analysis.Transplantation 2011; 91: 1110. 15. Kayler LK, Magliocca J, Kim RD, et al. Single kidney transplantation from young pediatric donors in the United States. Am J Transplant 2009; 9: 2745.

Descending Aortic and Innominate Artery Cannulation for Aortic Arch Repair With Mildly Hypothermic Continuous Cardiopulmonary Bypass in Infants and Children

A technique is described for exposure of the descending aorta, allowing separate arterial cannulation for perfusion of the upper and lower body during reconstruction of the aortic arch, maintaining continuous full-flow cardiopulmonary bypass to the entire body. This single technique is applicable to all aortic arch pathologies and allows an unhurried aortic reconstruction in an unobstructed field.

Anoxic ventilation improves systemic perfusion during extracorporeal circulation with uncontrolled systemic-to-pulmonary shunt.

Uncontrolled systemic-to-pulmonary shunt results in decreased systemic flow during extracorporeal life support (ECLS). Ligation of systemic-to-pulmonary shunts during ECLS is associated with poor outcome and is not always readily achieved. In ex vivo preparations, alveolar hypoxia results in pulmonary vasoconstriction despite normoxic pulmonary perfusate. We hypothesized that anoxic ventilation would result in reduced pulmonary shunting and increased systemic flow during ECLS in piglets with systemic-to-pulmonary shunt. Four piglets were placed on ECLS with right and left atrial drainage. A shunt was created between the bicarotid trunk and pulmonary artery, using 5-mm ePTFE tubing. Inspired oxygen was reduced to <1% for 10 minutes, then returned to room air; pH, hematocrit, temperature, ventilatory pressures, and total pump flow were maintained constant. Systemic arterial pressure and right atrial return volume and hemoglobin saturation were measured: All decreased significantly upon shunt unclamping. Anoxic ventilation caused increased systemic pressure (34 vs. 28 mm Hg, p < 0.05), flow (335 vs. 278 mL/min, p < 0.05), and systemic venous saturation (53% vs. 48%, p = 0.13) compared with room air ventilation. In conclusion, anoxic ventilation during normoxic ECLS in subjects with systemic-to-pulmonary shunts results in a significant and potentially clinically useful reduction in pulmonary shunting.

“Closed-Vein” Technique for Primary Sutureless Repair of Anomalous Pulmonary Venous Connection

Deep hypothermic circulatory arrest or low-flow bypass are commonly used in primary repair of total anomalous pulmonary venous connection, or individual veins may be dissected to allow clamp or snare application, in order to provide a bloodless field for anastomosis by the direct or sutureless marsupialization technique. In the described technical modification, the marsupialization of the opened atrium to the posterior pericardium is completed before opening the pulmonary venous confluence, allowing bloodless exposure during full-flow normothermic bypass. In addition, vein branch dissection is avoided.