In hypoplastic left heart patients is Sano shunt compared with modified Blalock-Taussig shunt associated with deleterious effects on ventricular performance?

Femoral vein homograft as Sano shunt results in improved pulmonary artery growth after Norwood operation

OBJECTIVE

To evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation.

METHODS

A retrospective review of all patients who survived to the second stage following Norwood-Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation.

RESULTS

A total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5-6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130-460) versus 165 (108-234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations.

CONCLUSIONS

Utilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood-Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.

Cognitive Development of School-Age Hypoplastic Left Heart Syndrome Survivors: A Single Center Study

Neurological and radiologic research results show an abnormal cerebral microstructure as well as abnormal neurodevelopment in patients treated for hypoplastic left heart syndrome. The aim of this study was to assess the varying cognitive performance these children have developed in dependence upon prenatal diagnosis, surgical techniques, surgical learning effects, anatomy, perfusion techniques, gender, pedagogic, and sociodemographic parameters in comparison to age-adjusted normative values. School-age children (6.3-16.9 years) with hypoplastic left heart syndrome, who were treated at the Children's heart Center Linz between 1997 and 2009, (n = 74), were surveyed in reference to cognitive achievements. 43 patients were examined prospectively by psychologists using the Wechsler intelligence scale for children IV in order to determine the respective total intelligence quotient index for each child's developmental stage. The mean index was 84.5 (percentile rank 26.4). The statistical spread and standard deviation ranged from a minimum of 40 to a maximum of 134 ± 20.8. The results for verbal comprehension, perceptual reasoning, and processing speed corresponded with total index results and were thus lower than the mean value of the normative values. The assessment of working memory showed results in the average. Prenatal diagnosis, type of lung perfusion, anatomy, and various cerebral perfusion techniques did not significantly affect the cognitive results of the patients. The results show that hypoplastic left heart syndrome patients can be successfully tutored formally as well as personally in cognitive areas, although when compared to healthy children, they showed lower results for intellectual area parameters.

Arrhythmias After Stage I Hybrid Palliation in Single-Ventricle Patients

The hybrid procedure is an alternative palliative strategy for patients with single-ventricle physiology. No data exist documenting the incidence of arrhythmias after the hybrid procedure. Goal of this study was to determine the incidence and type of arrhythmias in patients undergoing the hybrid procedure. A retrospective chart review was performed including all patients undergoing the hybrid procedure between January of 2010 through December of 2013. Sixty-five patients underwent the hybrid procedure during this time period (43 HLHS, 22 other). Average gestational age at admission was 37.7 weeks. Average age at time of procedure was 7.6 days. Five patients had documented arrhythmias (7.7 %). Four were supraventricular tachycardias, and 1 was a sinus bradycardia. One patient with arrhythmia died during hospitalization, and another patient with arrhythmia died during the interstage period. Hybrid palliation for patients with single-ventricle physiology has a low incidence of arrhythmias. In this cohort of patients, arrhythmias did not contribute to mortality. There was a trend toward association between arrhythmias and longer total length of hospital stay.

Introduction to a Norwood program in an emerging economy: learning curve of a single center

BACKGROUND

There has been a notable improvement in the outcome of stage 1 palliation for hypoplastic left heart syndrome (HLHS) in recent years. Nevertheless, developing a new Norwood program requires a steep learning curve, especially in emerging economies where rapid population growth brings a high volume of patients but, on the other hand, resources are limited. In this paper we aimed to summarize the initial results of a single center.

METHODS

Hospital records of 21 patients were reviewed for all patients having a stage 1 palliation procedure for HLHS between May 2011 and May 2013. There were 13 male (62%) and 8 female (38%) patients. Median age was 14 days (range, 4-74 days) and median weight was 3030 g (2600-3900 g). HLHS was defined as mitral or aortic stenosis or atresia (or both) in the presence of normally related great vessels and a hypoplastic left ventricle. Transthoracic echocardiography was the diagnostic modality used in all patients. All procedures but one were performed using an antegrade selective cerebral perfusion method and moderate hypothermia. Cerebral perfusion was monitored with cerebral oximetry in all patients. Modified ultrafiltration was routinely used in all patients.

RESULTS

Overall hospital mortality was 47.6% (n = 10). Mortality rates considerably decreased from the first year to second year (69% and 12.5% respectively). No risk factors were identified for mortality.

CONCLUSIONS

Surgical palliation of neonates with hypoplastic left heart syndrome continues to be a challenge. To decrease the overall mortality nationwide and improve outcomes, a referral center with a dedicated team is necessary in emerging economies.

[Update on pediatric cardiology and congenital heart disease: imaging techniques, pulmonary arterial hypertension, hybrid treatment, and surgical treatment]

This article contains a review of the most significant contributions to pediatric cardiology and congenital heart disease reported in publications between September 2009 and August 2010. The review focuses on imaging techniques, new treatment for pulmonary arterial hypertension in pediatric patients, and therapy in general (e.g. hybrid treatment and surgical treatment). With regard to imaging techniques, the review highlights the increasing application of congenital heart disease diagnosis during fetal life, the introduction of new echocardiographic techniques (e.g. tissue Doppler imaging, two-dimensional speckle-tracking imaging and three-dimensional echocardiography) into routine clinical practice, and the growing use of cardiac CT and magnetic resonance imaging in diagnosis and the assessment of cardiac function, respectively. The role played by cardiac interventions continues to increase and cardiac surgery is becoming more advanced and has, in some cases, been combined with hybrid techniques. However, there are still a number of controversial issues in cardiac surgery that have not yet been resolved, such as whether or not fenestration should be used with Fontan surgery, the optimum type of correction for hypoplastic left heart syndrome, and the best conduit for pulmonary artery replacement.

Establishment of right ventricle-pulmonary artery continuity as the first-stage palliation in older infants with pulmonary atresia with ventricular septal defect may be preferable to use of an arterial shunt

OBJECTIVES

Right ventricle-pulmonary artery (RV-PA) conduit and systemic-to-pulmonary artery (S-PA) shunt in younger infants for the first-stage palliation with pulmonary atresia with ventricular septal defect (PAVSD) obtained good results. However, the pulmonary arteries (PA) grow slow in older infants undergoing an S-PA shunt. We compared the clinical outcomes of the two procedures in older infants with PAVSD.

METHODS

A total of 48 patients with PAVSD underwent the first-stage palliative procedure between January 2010 and July 2012. Patients were divided into the RV-PA group and the S-PA group based on whether they had an RV-PA conduit (n = 24) or an S-PA shunt (n = 24). The early and late outcomes were compared between groups.

RESULTS

There was no significant difference in in-hospital mortality, mechanical ventilation time, paediatric intensive care unit stay and hospital stay between groups (all P > 0.05). The RV-PA conduits were associated with better PA growth compared with the S-PA shunts (P < 0.001). The RV-PA group had a higher rate of second-stage biventricular surgery compared with the S-PA group (P = 0.03). The early outcomes among different conduits of the RV-PA conduit were not different (all P > 0.05). A positive correlation was found between the size of conduits and body weight (R(2) = 0.684, P < 0.001).

CONCLUSIONS

In older infants with PAVSD who underwent the first-stage palliative procedure, early outcomes showed no difference between the RV-PA conduit group and the S-PA shunt group. The RV-PA conduits were associated with better growth of the PA and higher rates of second-stage biventricular repair. Autologous pericardium is a good choice for RV-PA conduits, and there is a correlation between body weight and size of conduit.

Protocol-driven enteral nutrition in critically ill children: a systematic review

Enteral nutrition (EN) protocols are thought to improve clinical outcomes in the pediatric intensive care unit (PICU); however, critical evaluation of their efficacy is limited. We conducted a systematic review with the aim of assessing the effect of EN protocols on important clinical outcomes in these children. We searched MEDLINE, Cochrane Database for Reviews, Embase, and CINAHL using predetermined keywords and MESH terms. We included randomized controlled trials (RCTs) and observational studies that involved EN protocols in children admitted to the PICU for >24 hours. We included studies that reported at least 1 of our outcomes of interest. Studies that exclusively studied premature neonates or adults were excluded. Primary outcomes were PICU or hospital mortality, PICU or hospital length of stay (LOS), duration of mechanical ventilation, gastrointestinal (GI) complications, and infective complications. Secondary outcomes were time to initiate feeds and time to achieve goal feeds. In total, we included 9 studies (total 1564 children) in our systematic review (1 RCT, 4 before-and-after studies, 1 single-arm cohort study, 1 prospective descriptive study, and 2 audits). There is low-level evidence that the use of EN protocols is associated with a reduction in GI and infective complications and improved timeliness of feed initiation and achievement of goal feeds. Current medical literature does not have compelling data on the effects of an EN protocol on clinical outcomes among critically ill children. Future clinical trials should look into using standardized interventions and outcome measures to strengthen the existing evidence.

Impact of shunt type on growth of pulmonary arteries after norwood stage I procedure: current best available evidence

The past decade has seen a substantial improvement in the outcome following surgical palliation for hypoplastic left heart syndrome. This has been attributed to modifications in the surgical as well as postoperative management strategies. One such modification is the reemergence of the right ventricle to pulmonary artery (RV-PA) shunt as an alternative to the modified Blalock-Taussig (mBT) shunt as the source of pulmonary blood flow. The RV-PA shunt has been shown to improve the immediate surgical outcome compared with the classic Norwood procedure with an mBT shunt. Despite the several reported advantages, the impact of the RV-PA shunt on growth of the pulmonary arteries and incidence of late development of central PA stenosis remains unclear. This systematic review evaluates the current best available evidence to address this issue and concludes that the evidence from retrospective studies and only available randomized controlled trial (RCT) is conflicting. The retrospective studies predominantly suggest that the Norwood procedure with RV-PA shunt may have favorable effects on the development of the pulmonary arteries due to even distribution of pulmonary blood flow with greater distal left pulmonary artery growth, resulting in more balanced distal branch pulmonary artery size albeit with a greater degree of central pulmonary artery hypoplasia needing surgical attention. On the contrary, the RCT reports that the overall size of the pulmonary artery on angiography before the stage II procedure was smaller in the RV-PA shunt group than in the mBT shunt group, with no information available on incidence of central pulmonary hypoplasia.

Stage one Norwood procedure in an emerging economy:Initial experience in a single center

Objective:

The evolution of surgical skills and advances in pediatric cardiac intensive care has resulted in Norwood procedure being increasingly performed in emerging economies. We reviewed the feasibility and logistics of performing stage one Norwood operation in a limited-resource environment based on a retrospective analysis of patients who underwent this procedure in our institution.

Methods:

Retrospective review of medical records of seven neonates who underwent Norwood procedure at our institute from October 2010 to August 2012.

Results:

The median age at surgery was 9 days (range 5-16 days). All cases were done under deep hypothermic cardiopulmonary bypass and selective antegrade cerebral perfusion. The median cardiopulmonary bypass (CPB) time was 240 min (range 193-439 min) and aortic cross-clamp time was 130 min (range 99-159 min). A modified Blalock-Taussig (BT) shunt was used to provide pulmonary blood flow in all cases. There were two deaths, one in the early postoperative period. The median duration of mechanical ventilation was 117 h (range 71-243 h) and the median intensive care unit (ICU) stay was 12 days (range 5-16 days). Median hospital stay was 30.5 days (range 10-36 days). Blood stream sepsis was reported in four patients. Two patients had preoperative sepsis. One patient required laparotomy for intestinal obstruction.

Conclusions:

Stage one Norwood is feasible in a limited-resource environment if supported by a dedicated postoperative intensive care and protocolized nursing management. Preoperative optimization and prevention of infections are major challenges in addition to preventing early circulatory collapse.

Tricuspid valve repair in single ventricle: timing and techniques

Tricuspid valve performance in the systemic circulation is known to have important implications for survival and functional status after univentricular palliation of hypoplastic left heart syndrome (HLHS). Moderate to severe tricuspid valve regurgitation is not an uncommon finding in patients with HLHS undergoing staged surgical reconstruction. It can result from either abnormal valve morphology or incomplete leaflet coaptation, or both. But first and foremost, any aortic arch re-obstruction must be excluded. Development of significant tricuspid regurgitation (TR) remains an obstacle in improving survival after the Norwood procedure and likely compromised functional health after the Fontan procedure. Thus, surgical intervention for minimizing tricuspid valve deterioration and significant TR seems pivotal to improving long-term outcomes for patients with HLHS. This article provides an overview of the etiology and mechanisms of development of significant TR, natural history, indications for surgical intervention, and focuses on timing, techniques, and clinical outcomes of tricuspid valve repair in the setting of single ventricle.