Children's informed signified and voluntary consent to heart surgery: Professionals' practical perspectives.

BACKGROUND: The law and literature about children's consent generally assume that patients aged under-18 cannot consent until around 12 years, and cannot refuse recommended surgery. Children deemed pre-competent do not have automatic rights to information or to protection from unwanted interventions. However, the observed practitioners tend to inform young children s, respect their consent or refusal, and help them to "want" to have the surgery. Refusal of heart transplantation by 6-year-olds is accepted. RESEARCH QUESTION: What are possible reasons to explain the differences between theories and practices about the ages when children begin to be informed about elective heart surgery, and when their consent or refusal begins to be respected? RESEARCH DESIGN, PARTICIPANTS AND CONTEXT: Research methods included reviews of related healthcare, law and ethics literature; observations and conversations with staff and families in two London hospitals; audio-recorded semi-structured interviews with a purposive sample of 45 healthcare professionals and related experts; interviews and a survey with parents and children aged 6- to 15-years having elective surgery (not reported in this paper); meetings with an interdisciplinary advisory group; thematic analysis of qualitative data and co-authorship of papers with participants. ETHICAL CONSIDERATIONS: Approval was granted by four research ethics committees/authorities. All interviewees gave their informed written consent. FINDINGS: Interviewees explained their views and experiences about children's ages of competence to understand and consent or refuse, analysed by their differing emphases on informed, signified or voluntary consent. DISCUSSION: Differing views about children's competence to understand and consent are associated with emphases on consent as an intellectual, practical and/or emotional process. Conclusion: Greater respect for children's practical signified, emotional voluntary and intellectual informed consent can increase respectful understanding of children's consent. Nurses play a vital part in children's practitioner-patient relationships and physical care and therefore in all three elements of consent.

Three-dimensional visualisation of the fetal heart using prenatal MRI with motion-corrected slice-volume registration: a prospective, single-centre cohort study.

BACKGROUND: Two-dimensional (2D) ultrasound echocardiography is the primary technique used to diagnose congenital heart disease before birth. There is, however, a longstanding need for a reliable form of secondary imaging, particularly in cases when more detailed three-dimensional (3D) vascular imaging is required, or when ultrasound windows are of poor diagnostic quality. Fetal MRI, which is well established for other organ systems, is highly susceptible to fetal movement, particularly for 3D imaging. The objective of this study was to investigate the combination of prenatal MRI with novel, motion-corrected 3D image registration software, as an adjunct to fetal echocardiography in the diagnosis of congenital heart disease. METHODS: Pregnant women carrying a fetus with known or suspected congenital heart disease were recruited via a tertiary fetal cardiology unit. After initial validation experiments to assess the general reliability of the approach, MRI data were acquired in 85 consecutive fetuses, as overlapping stacks of 2D images. These images were then processed with a bespoke open-source reconstruction algorithm to produce a super-resolution 3D volume of the fetal thorax. These datasets were assessed with measurement comparison with paired 2D ultrasound, structured anatomical assessment of the 2D and 3D data, and contemporaneous, archived clinical fetal MRI reports, which were compared with postnatal findings after delivery. FINDINGS: Between Oct 8, 2015, and June 30, 2017, 101 patients were referred for MRI, of whom 85 were eligible and had fetal MRI. The mean gestational age at the time of MRI was 32 weeks (range 24-36). High-resolution (0·50-0·75 mm isotropic) 3D datasets of the fetal thorax were generated in all 85 cases. Vascular measurements showed good overall agreement with 2D echocardiography in 51 cases with paired data (intra-class correlation coefficient 0·78, 95% CI 0·68-0·84), with fetal vascular structures more effectively visualised with 3D MRI than with uncorrected 2D MRI (657 [97%] of 680 anatomical areas identified vs 358 [53%] of 680 areas; p<0·0001). When a structure of interest was visualised in both 2D and 3D data (n=358), observers gave a higher diagnostic quality score for 3D data in 321 (90%) of cases, with 37 (10%) scores tied with 2D data, and no lower scores than for 2D data (Wilcoxon signed rank test p<0·0001). Additional anatomical features were described in ten cases, of which all were confirmed postnatally. INTERPRETATION: Standard fetal MRI with open-source image processing software is a reliable method of generating high-resolution 3D imaging of the fetal vasculature. The 3D volumes produced show good spatial agreement with ultrasound, and significantly improved visualisation and diagnostic quality compared with source 2D MRI data. This freely available combination requires minimal infrastructure, and provides safe, powerful, and highly complementary imaging of the fetal cardiovascular system. FUNDING: Wellcome Trust/EPSRC Centre for Medical Engineering, National Institute for Health Research.

Early Postnatal Echocardiography in Neonates with a Prenatal Suspicion of Coarctation of the Aorta.

Coarctation of the aorta (COA) is suspected prenatally when there is ventricular asymmetry, arterial disproportion, and hypoplasia of the aortic arch/isthmus. The presence of fetal shunts creates difficulty in prenatal confirmation of the diagnosis so serial echocardiography after birth is necessary to confirm or refute the diagnosis. The first neonatal echocardiogram in prenatally suspected cases of COA was assessed for prediction of neonatal COA repair (NCOAR). This included morphological assessment, measurement of the aortic arch and calculation of the distal arch index (DAI = distance between left common carotid and left subclavian artery/diameter of the distal arch). NCOAR was undertaken in 23/60 (38%) cases. Transverse arch, aortic isthmus z-score, and DAI had an area under the receiver operator curve of 0.88 (95% CI 0.77-0.98), 0.86 (95% CI 0.75-0.96), and 0.84 (95% CI 0.74-0.95), respectively for the prediction of NCOAR. Using transverse arch z-score threshold < - 3 gave sensitivity 100%, NPV: 100%, specificity 76%; aortic isthmus z-score < - 3: NPV 92%, specificity 62% and DAI > 1.4: NPV 88%, specificity 78%. The size of the distal aortic arch in infants with a common origin of the innominate artery and left common carotid artery who did not require COA repair was similar to the NCOAR cases (p = 0.22). The early postnatal assessment of the size and morphology of the aortic arch can assist in risk stratification for development of neonatal COA. The branching pattern of the head/neck vessels impacts on the size of the distal aortic arch adding to the complexity of predicting COA based on vessel size.

Right ventricular systolic function in hypoplastic left heart syndrome: A comparison of manual and automated software to measure fractional area change.

BACKGROUND: Quantitative echocardiographic assessment of right ventricular function is important in children with hypoplastic left heart syndrome (HLHS). The aim of this study was to examine the repeatability of different echocardiographic techniques, both manual and automated, to measure fractional area change (FAC) in patients with HLHS and to correlate these measurements with magnetic resonance imaging (MRI)-derived ejection fraction (EF). METHODS: Fifty-one children with HLHS underwent transthoracic echocardiography and cardiac MRI under the same general anesthetic as part of routine inter-stage assessment. FAC was measured from the apical four-chamber view using three different techniques: velocity vector imaging (VVI) (Syngo USWP 3.0; Siemens Healthineers), QLAB (Q-lab R 10.0; Philips Healthcare), and manual endocardial contour tracing (Xcelera, Philips Healthcare). Intra- and inter-observer variability was calculated using intra-class correlation coefficient (ICC). FAC was correlated with MRI EF calculated using a single standard method. RESULTS: Fractional area change had a good correlation with MRI-derived EF with an R value for VVI, QLAB, and manual methods of .7, .6, and .4, respectively. Intra- and inter-observer variability for FAC was good for automated echocardiographic methods (ICC>.85) but worse for manual method particularly inter-observer variability of FAC and end-systolic area. Both automated techniques tended to produce higher FAC values compared with manual measurements (P<.001). CONCLUSION: Automation improves the repeatability of FAC in HLHS. There are some differences between automated software in terms of correlation with MRI-derived EF. Measurement bias and wide limits of agreement mean that the same echocardiographic technique should be used during the follow-up of individual patients.

Interstage somatic growth in children with hypoplastic left heart syndrome after initial palliation with the hybrid procedure.

Introduction The hybrid procedure is one mode of initial palliation for hypoplastic left heart syndrome. Subsequently, patients proceed with either the "three-stage" pathway - comprehensive second stage followed by Fontan completion - or the "four-stage" pathway - Norwood procedure, hemi-Fontan, or Fontan completion. In this study, we describe somatic growth patterns observed in the hybrid groups and a comparison primary Norwood group. METHODS: A retrospective analysis of patients who have undergone hybrid procedure and Fontan completion was performed. Weight-for-age and height-for-age z-scores were recorded at each operation. RESULTS: We identified 13 hybrid patients - eight in the three-stage pathway and five in the four-stage pathway - and 49 Norwood patients. Weight: three stage: weight decreased from hybrid procedure to comprehensive second stage (-0.4±1.3 versus -2.3±1.4, p<0.01) and then increased to Fontan completion (-0.4±1.5 versus -0.6±1.4, p<0.01); four stage: weight decreased from hybrid procedure to Norwood (-2.0±1.4 versus -3.3±0.9, p=0.06), then stabilised to hemi-Fontan. Weight increased from hemi-Fontan to Fontan completion (-2.7±0.6 versus -1.0±0.7, p=0.01); primary Norwood group: weight decreased from Norwood to hemi-Fontan (p<0.001) and then increased to Fontan completion (p<0.001). Height: height declined from hybrid procedure to Fontan completion in the three-stage group. In the four-stage group, height decreased from hybrid to hemi-Fontan, and then increased to Fontan completion. The Norwood group decreased in height from Norwood to hemi-Fontan, followed by an increase to Fontan completion. CONCLUSION: In this study, we show that patients undergoing the hybrid procedure have poor weight gain before superior cavopulmonary connection, before returning to baseline by Fontan completion. This study identifies key periods to target poor somatic growth, a risk factor of morbidity and worse neurodevelopmental outcomes.

Cardiovascular magnetic resonance catheterization derived pulmonary vascular resistance and medium-term outcomes in congenital heart disease.

BACKGROUND: Selection of patients with congenital heart disease for surgical septation in biventricular repair or surgical palliation in functionally single ventricles requires low pulmonary vascular resistance (PVR). Where there is uncertainty, PVR can be assessed using hybrid cardiovascular magnetic resonance (CMR) and fluoroscopic (X-Ray) guided cardiac catheterizations (XMR). CMR/XMR catheterization is a validated technique for accurate assessment of pulmonary vascular resistance. However, data concerning its application in clinical practice is lacking. METHODS: PVR assessments were performed in 167 studies in 149 congenital heart disease patients by CMR/XMR catheterization. Data was collated on patient demographics, procedural data, complications and outcomes. Institutional ethics approval was obtained. RESULTS: Median age was 3.6 years (6 days-67 years) and weight 13.8 kg (2.3-122 kg). One hundred and eight studies were in biventricular circulations and 59 in functionally single ventricles. Median radiation dose was 0.72 mSv. A baseline Qp:Qs ≤2.75 in biventricular circulations with left-to-right shunts predicted a PVR ≥6 WU x m(2) with 100% sensitivity and 48% specificity. Median follow up until death or last review was 4.2 years (4 days-11 years). Eighty-four patients had a surgical or catheter intervention based on CMR/XMR catheterization findings at a median of 94 days after the study. This included successful biventricular repair at resting PVR values ≤6 WU x m(2) and Fontan completion at ≤4 WU x m(2). CONCLUSION: PVR measured by CMR/XMR catheterization allows accurate stratification for intervention in patients with congenital heart disease in both, biventricular and univentricular circulations.

Retrospective Cohort Study of Additional Procedures and Transplant-Free Survival for Patients With Functionally Single Ventricle Disease Undergoing Staged Palliation in England and Wales.

BACKGROUND: Reinterventions may influence the outcomes of children with functionally single-ventricle (f-SV) congenital heart disease. METHODS AND RESULTS: We undertook a retrospective cohort study of children starting treatment for f-SV between 2000 and 2018 in England, using the national procedure registry. Patients were categorized based on whether they survived free of transplant beyond 1 year of age. Among patients who had transplant-free survival beyond 1 year of age, we explored the relationship between reinterventions in infancy and the outcomes of survival and Fontan completion, adjusting for complexity. Of 3307 patients with f-SV, 909 (27.5%), had no follow-up beyond 1 year of age, among whom 323 (35.3%) had ≥1 reinterventions in infancy. A total of 2398 (72.5%) patients with f-SV had transplant-free survival beyond 1 year of age, among whom 756 (31.5%) had ≥1 reinterventions in infancy. The 5-year transplant-free survival and cumulative incidence of Fontan, among those who survived infancy, were 93.4% (95% CI, 92.4%-94.4%) and 79.3% (95% CI, 77.4%-81.2%), respectively. Both survival and Fontan completion were similar for those with a single reintervention and those who had no reinterventions. Patients who had >1 additional surgery (adjusted hazard ratio, 3.93 [95% CI, 1.87-8.27] P<0.001) had higher adjusted risk of mortality. Patients who had >1 additional interventional catheter (adjusted subdistribution hazard ratio, 0.71 [95% CI, 0.52-0.96] P=0.03) had a lower likelihood of achieving Fontan. CONCLUSIONS: Among children with f-SV, the occurrence of >1 reintervention in the first year of life, especially surgical reinterventions, was associated with poorer prognosis later in childhood.

Flecainide toxicity: ECG changes associated with supratherapeutic levels in milk-fed infants.

Flecainide is a class 1C antiarrhythmic and is highly effective for treating a wide range of arrhythmias. It is not licensed for children under the age of 12 years, but has been used safely for years in young children, particularly when first-line agents are not effective. Although toxicity does occur in both adult and paediatric populations, there have been very few reported instances of flecainide toxicity in neonates and children. Supratherapeutic levels of flecainide manifests on ECG with prolongation of the PR interval, QRS duration and QT, and can lead to life-threatening arrhythmias. In milk-fed infants receiving flecainide, regular feeding patterns are paramount to achieve a steady therapeutic state, as milk and dairy products are known to reduce the absorption of flecainide. This case series details four milk-fed infants admitted with ECG changes secondary to flecainide toxicity.

Children's understanding and consent to heart surgery: Multidisciplinary teamwork and moral experiences.

Mainstream law and ethics literature on consent to children's surgery contrasts with moral experiences of children and adults observed in two heart surgery centres. Research interviews were conducted with 45 practitioners and related experts, and with 16 families of children aged 6 to 15, admitted for non-urgent surgery, as well as an online survey. Thematic data analysis was informed by critical realism and childhood studies.Impersonal adult-centric mainstream literature assumes young children cannot consent. It is based on dichotomies: adult/child, competent/incompetent, respect or protect children, inform or distract them, use time swiftly or flexibly, verbal/non-verbal communication, respect or control children and reason/emotion.Through their moral experiences, adults and children resolve these seeming dichotomies. Through understanding young children's reasoning and emotions about complex distressing decisions related to heart surgery, adults share knowledge, control, trust and respect with them. They see children's consent or refusal before non-urgent surgery as a shared personal moral experience within the child's life course, beyond mere legal compliance. Adults help children to understand and 'want' the surgery that offers things they value: better health or to 'be more like their friends'. If children are not convinced, sometimes surgery is postponed or occasionally cancelled.

Long-term survival and center volume for functionally single-ventricle congenital heart disease in England and Wales.

OBJECTIVES: Long-term survival is an important metric for health care evaluation, especially in functionally single-ventricle (f-SV) congenital heart disease (CHD). This study's aim was to evaluate the relationship between center volume and long-term survival in f-SV CHD within the centralized health care service of England and Wales. METHODS: This was a retrospective cohort study of children born with f-SV CHD between 2000 and 2018, using the national CHD procedure registry, with survival ascertained in 2020. RESULTS: Of 56,039 patients, 3293 (5.9%) had f-SV CHD. Median age at first intervention was 7 days (interquartile range [IQR], 4, 27), and median follow-up time was 7.6 years (IQR, 1.0, 13.3). The largest diagnostic subcategories were hypoplastic left heart syndrome, 1276 (38.8%); tricuspid atresia, 440 (13.4%); and double-inlet left ventricle, 322 (9.8%). The survival rate at 1 year and 5 years was 76.8% (95% confidence interval [CI], 75.3%-78.2%) and 72.1% (95% CI, 70.6%-73.7%), respectively. The unadjusted hazard ratio for each 5 additional patients with f-SV starting treatment per center per year was 1.04 (95% CI, 1.02-1.06), P < .001. However, after adjustment for significant risk factors (diagnostic subcategory; antenatal diagnosis; younger age, low weight, acquired comorbidity, increased severity of illness at first procedure), the hazard ratio for f-SV center volume was 1.01 (95% CI, 0.99-1.04) P = .28. There was strong evidence that patients with more complex f-SV (hypoplastic left heart syndrome, Norwood pathway) were treated at centers with greater f-SV case volume (P < .001). CONCLUSIONS: After adjustment for case mix, there was no evidence that f-SV center volume was linked to longer-term survival in the centralized health service provided by the 10 children's cardiac centers in England and Wales.

Three-dimensional dual-phase whole-heart MR imaging: clinical implications for congenital heart disease.

PURPOSE: To identify which rest phase (systolic or diastolic) is optimum for assessing or measuring cardiac structures in the setting of three-dimensional (3D) whole-heart imaging in congenital heart disease (CHD). MATERIALS AND METHODS: The study was approved by the institutional review board; informed consent was obtained. Fifty children (26 male and 24 female patients) underwent 3D dual-phase whole-heart imaging. Cardiac structures were analyzed for contrast-to-noise ratio (CNR) and image quality. Cross-sectional measurements were taken of the aortic arch, right ventricular (RV) outflow tract (RVOT) and pulmonary arteries. Normally distributed variables were compared by using paired t tests, and categorical data were compared by using Wilcoxon signed-rank test. RESULTS: Mean CNR and image quality were significantly (all P < .05) greater in systole for the right atrium (CNR, 8.9 vs 7.5; image quality, 438 vs 91), left atrium (CNR, 8.0 vs 5.3; image quality, 1006 vs 29), RV (CNR, 10.6 vs 8.2; image quality, 131 vs 23), LV (CNR, 9.4 vs 7.7; image quality, 125 vs 28), and pulmonary veins (CNR, 6.2 vs 4.9; image quality, 914 vs 32). Conversely, diastolic CNR was significantly higher in the aorta (9.2 vs 8.2; P = .013) and diastolic image quality was higher for the left pulmonary artery (238 vs 62; P = .007), right pulmonary artery (219 vs 35; P < .001), and for imaging of an area after an arterial stenosis (164 vs 7; P < .001). All aortic arch and RVOT cross-sectional measurements were significantly (P < .05) greater in systole (narrowest point of arch, 70 vs 53 mm(2); descending aorta, 71 vs 58 mm(2); transverse arch, 293 vs 275 mm(2); valvar RVOT, 291 vs 268 mm(2); supravalvar RVOT, 337 vs 280 mm(2); prebifurcation RVOT, 329 vs 259 mm(2)). CONCLUSION: Certain structures in CHD are better imaged in systole and others in diastole, and therefore, the dual-phase approach allows a higher overall success rate. This approach also allows depiction of diameter changes between systole and diastole and is therefore preferable to standard single-phase sequences for the planning of interventional procedures.

Early superior cavopulmonary connection with preoperative computer tomography shows comparable outcomes for infants following Norwood palliation.

OBJECTIVES: There is increasing evidence that performing superior cavopulmonary connection (SCPC) at 3 months reduces mortality: reducing the risky 'interstage' period, volume off-loading the ventricle and reducing coronary steal, hopefully preserving ventricular function. Our objective was to describe our experience of early SCPC with preoperative computer tomography (CT) assessment compared to later connection at 6 months. METHODS: Patients undergoing Norwood procedure from 2005 to 2020 were divided into 2 eras were described and compared. Era 1 from 2005 to 2016 when SCPC was undertaken at 6 months: and era 2 (2017-2020) when an earlier operation was performed. Demographics, mortality (interstage, early and late following SCPC) and data on postoperative course and complications were recorded. RESULTS: In era 1, 191 patients underwent Norwood (120 survivors to SCPC) and 28 patients (23 survivors) in era 2. There were no significant differences in the demographics. Interstage mortality was 17.8% in era 1 and 8.0% in era 2 but not significantly significant (P = 0.22). The median (interquartile range) age at pre-imaging and SCPC was significantly lower: 99 (81-120) vs 77 (47-102) days and 175 (117-208) vs 106 (102-122) days in era 1 vs era 2 (P < 0.005). Weight was lower at SCPC in era 2 [mean (standard deviation) 6.2 kg (1.2) vs 5.1 kg (0.8), P < 0.05]. Intubation time and total length of stay were not statistically different. Median intensive care unit stay was statistically significantly longer, but not clinically significant: 2.5 (2-4) vs 3 (3-5) days, respectively (P < 0.05). There was no significant difference in early or late mortality, rates of diagnostic or interventional catheter, postoperative magnetic resonance imaging/CT or stroke. Logistic regression analysis demonstrates increasing age at SCPC was associated with increased chance of stroke or early death (P = 0.043). CONCLUSIONS: Early SCPC with CT assessment is feasible and although intensive care unit length of stay was slightly longer there was no change in the overall length of stay and no change in postoperative mortality or complications.

Unlocking the Non-invasive Assessment of Conduit and Reservoir Function in the Aorta : The Obstructive Descending Aorta in HLHS.

Aortic surgeries in congenital conditions, such as hypoplastic left heart syndrome (HLHS), aim to restore and maintain the conduit and reservoir functions of the aorta. We proposed a method to assess these two functions based on 4D flow MRI, and we applied it to study the aorta in pre-Fontan HLHS. Ten pre-Fontan HLHS patients and six age-matched controls were studied to derive the advective pressure difference and viscous dissipation for conduit function, and pulse wave velocity and elastic modulus for reservoir function. The reconstructed neo-aorta in HLHS subjects achieved a good conduit function at a cost of an impaired reservoir function (69.7% increase of elastic modulus). The native descending HLHS aorta displayed enhanced reservoir (elastic modulus being 18.4% smaller) but impaired conduit function (three-fold increase in peak advection). A non-invasive and comprehensive assessment of aortic conduit and reservoir functions is feasible and has potentially clinical relevance in congenital vascular conditions.

Noninvasive Imaging in Interventional Cardiology: Hypoplastic Left Heart Syndrome.

Hypoplastic left heart syndrome (HLHS) is a spectrum of left heart underdevelopment leaving the left side unable to support the systemic circulation. If active management is pursued, then the condition is managed with staged palliation to the Fontan circulation, leaving a systemic right ventricle. Through all surgical stages, and even after completion of Fontan, there are multiple areas that may require intervention, most frequently the branch pulmonary arteries which are essential to a successful Fontan circulation. Echocardiography is the mainstay of assessment, but there is an increasing use of magnetic resonance imaging (MRI) and computed tomography (CT) particularly in relation to extracardiac structures which can be more challenging with echocardiography. Both MRI and CT require set-up, experience and training, and usually sedation or anesthetic in smaller children, but can provide excellent imaging to guide interventions. Cardiac MRI is also able to quantify right ventricular (RV) function which can be challenging on echocardiography. This article describes the modalities available and their use in assessing patients with HLHS prior to catheter interventions.

EDUCATIONAL SERIES IN CONGENITAL HEART DISEASE: The sequential segmental approach to assessment.

Sequential segmental analysis allows clear description of the cardiac structure in a logical fashion without assumptions and confusing nomenclature. Each segment is analysed, and then the connections described followed by any associated anomalies. For the echocardiographer there are several key features of the cardiac structures to help differentiate and accurately describe them.

Application of the Boston Technical Performance Score to intraoperative echocardiography.

BACKGROUND: The Technical Performance Score (TPS) developed by Boston Children's Hospital showed surgical outcomes correlate with adequacy of technical repair when implemented on pre-discharge echocardiograms. We applied this scoring system to intraoperative imaging in a tertiary UK congenital heart surgical centre. METHODS: After a period of training, intraoperative TPS (epicardial and/or transesophageal echocardiography) was instituted. TPS was used to inform intraoperative discussions and recorded on a custom-made database using the previously published scoring system. After a year, we reviewed the feasibility, results and relationship between the TPS and mortality, extubation time and length of stay. RESULTS: From 01 September 2015 to 04 July 2016, there were 272 TPS procedures in 251 operations with 208 TPS recorded. Seven patients had surgery with no documented TPS, three had operations with no current TPS score template available. Patients left the operating theatre with TPS optimal in 156 (75%), adequate 34 (16%) and inadequate 18 (9%). Of those with an optimal score on leaving theatre, ten had more than one period of cardiopulmonary bypass. All four deaths <30 days after surgery (1.9%) had optimal TPS. There was a statistically significant difference in extubation times in the RACHS category 4 patients (3 days vs 5 days, P < 0.05) and in PICU and total length of stay in the RACHS category three patients (2 and 8 days vs 12.5 and 21.5 days respectively) if leaving theatre with an inadequate result. CONCLUSIONS: Application of intraoperative TPS is feasible and provides a way of objectively recording intraoperative imaging assessment of surgery. An 'inadequate' TPS did not predict mortality but correlated with a longer ventilation time and longer length of stay compared to those with optimal or adequate scores.

Ventricular function and vascular dimensions after Norwood and hybrid palliation of hypoplastic left heart syndrome.

OBJECTIVE: Norwood and hybrid procedure are two options available for initial palliation of patients with hypoplastic left heart syndrome (HLHS). Our study aimed to assess potential differences in right ventricular (RV) function and pulmonary artery dimensions using cardiac magnetic resonance (CMR) in survivors with HLHS. METHODS: 42 Norwood (mean age 2.4±0.8) and 44 hybrid (mean age 2.0±1.0 years) patients were evaluated by CMR after stage II palliation prior to planned Fontan completion. Initial stage I Norwood procedure was performed using a modified Blalock-Taussig shunt, while the hybrid procedure consisted of bilateral pulmonary artery banding and arterial duct stenting. Need for reinterventions and subsequent outcomes were also assessed. RESULTS: Norwood patients had larger RV end-diastolic dimensions (91±23 vs 80±31 mL/m2, p=0.004) and lower heart rate (90±15 vs 102±13, p<0.001) than hybrid patients. Both Norwood and hybrid patients showed preserved global RV pump function (59±9 vs 59%±10%, p=0.91), while RV strain, strain rate and intraventricular synchrony were superior in the Norwood group. Pulmonary artery size was reduced (lower lobe index 135±74 vs 161±62 mm2/m2, p=0.02), and reintervention rate was significantly higher in the hybrid group whereas subsequent outcome did not differ significantly (p=0.24). CONCLUSIONS: Norwood and hybrid strategy were associated with equivalent and preserved global RV pump function while development of the pulmonary arteries and reintervention rate were superior using the Norwood approach. Impaired RV myocardial deformation as a potential marker of early RV dysfunction in the hybrid group may have a negative long-term impact in this population.