Exploring the Possible Impact of Echocardiographic Diastolic Function Parameters on Outcome in Paediatric Dilated Cardiomyopathy.

Diastolic dysfunction is an important determinant for prognosis and survival in several paediatric heart diseases. We aimed to explore its possible impact on outcome in children with dilated cardiomyopathy. From 2006 to 2016, children less than 18 years old with dilated cardiomyopathy were retrospectively enrolled. Echocardiographic diastolic function parameters and child outcomes were analysed. Of 43 children aged 0.2 to 16.1 years old referred with dilated cardiomyopathy, 8 patients required cardiac transplant or mechanical assist devices (18%), 24 had persistently abnormal left ventricular function and/or dilatation (56%) and 11 patients recovered (26%). There was no significant difference in mitral velocities on Tissue Doppler Imaging, mitral valve inflow velocities, isovolumic relaxation time, left atrial area z-score and mitral lateral E/e' ratios between patients with recovery and patients with disease progression or persistently abnormal ventricular function and/or dilation. This is the first study on childhood dilated cardiomyopathy to address individual echocardiographic diastolic function parameters and their association to recovery. In this study, echocardiographic parameters for diastolic function did not predict recovery.

Prioritising transplantation for adult congenital heart disease, UK national data.

OBJECTIVE: There are no multi-centre data on the outcomes of transplant for adult congenital heart disease (ACHD) outside of North America. The literature has identified a number of concerns for this population such as increased wait-list and early post-operative mortality. We investigated outcomes in a national cohort to see if these problems are replicated outside of America. METHODS: Adults (aged ≥16 years) undergoing primary heart transplantation 1995-2014 were identified in the UK Registry and registration, operative and post-transplantation related clinical factors were compared to non ACHD recipients. RESULTS: Of 3026 adults who underwent primary heart transplantation, 134 (4.4%) had ACHD (median age 30 years; 40.3% female). For the ACHD patients listed as urgent status, the time to transplant was not significantly different to non ACHD patients and ACHD were not more likely to die or be removed from the wait list. Despite ACHD recipients having longer hospital stays (27 vs. 22 days; p = 0.003) and worse 90-day survival (79.5% vs. 86.6%; p = 0.02), long-term post-transplantation survival was not significantly different. Creatinine clearance was significantly better in ACHD patients at follow-up. In the last 10 years of our study period, all single ventricle transplants have been restricted to experienced ACHD teams, one year survival for Fontan patients was 89.5%. CONCLUSIONS: The use of urgent listing appears to have benefited the ACHD group by allowing equal access to transplantation, and recent concentration of expertise for single ventricle transplants has been associated with excellent early survival.

The Inadequate Oxygen Delivery Index and Low Cardiac Output Syndrome Score As Predictors of Adverse Events Associated With Low Cardiac Output Syndrome Early After Cardiac Bypass.

OBJECTIVES: To evaluate the effectiveness of two scoring systems, the inadequate oxygen delivery index, a risk analytics algorithm (Etiometry, Boston, MA) and the Low Cardiac Output Syndrome Score, in predicting adverse events recognized as indicative of low cardiac output syndrome within 72 hours of surgery. DESIGN: A retrospective observational pair-matched study. SETTING: Tertiary pediatric cardiac ICU. PATIENTS: Children undergoing cardiac bypass for congenital heart defects. Cases experienced an adverse event linked to low cardiac output syndrome in the 72 hours following surgery (extracorporeal membrane oxygenation, renal replacement therapy, cardiopulmonary resuscitation, and necrotizing enterocolitis) and were matched with a control patient on criteria of procedure, diagnosis, and age who experienced no such event. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of a total 536 bypass operations in the study period, 38 patients experienced one of the defined events. Twenty-eight cases were included in the study after removing patients who suffered an event after 72 hours or who had insufficient data. Clinical and laboratory data were collected to derive scores for the first 12 hours after surgery. The inadequate oxygen delivery index was calculated by Etiometry using vital signs and laboratory data. A modified Low Cardiac Output Syndrome Score was calculated from clinical and therapeutic markers. The mean inadequate oxygen delivery and modified Low Cardiac Output Syndrome Score were compared within each matched pair using the Wilcoxon signed-rank test. Inadequate oxygen delivery correctly differentiated adverse events in 13 of 28 matched pairs, with no evidence of inadequate oxygen delivery being higher in cases (p = 0.71). Modified Low Cardiac Output Syndrome Score correctly differentiated adverse events in 23 of 28 matched pairs, with strong evidence of a raised score in low cardiac output syndrome cases (p < 0.01). CONCLUSIONS: Although inadequate oxygen delivery is an Food and Drug Administration approved indicator of risk for low mixed venous oxygen saturation, early postoperative average values were not linked with medium-term adverse events. The indicators included in the modified Low Cardiac Output Syndrome Score had a much stronger association with the specified adverse events.

FIRST-line support for Assistance in Breathing in Children (FIRST-ABC): a multicentre pilot randomised controlled trial of high-flow nasal cannula therapy versus continuous positive airway pressure in paediatric critical care.

BACKGROUND: Although high-flow nasal cannula therapy (HFNC) has become a popular mode of non-invasive respiratory support (NRS) in critically ill children, there are no randomised controlled trials (RCTs) comparing it with continuous positive airway pressure (CPAP). We performed a pilot RCT to explore the feasibility, and inform the design and conduct, of a future large pragmatic RCT comparing HFNC and CPAP in paediatric critical care. METHODS: In this multi-centre pilot RCT, eligible patients were recruited to either Group A (step-up NRS) or Group B (step-down NRS). Participants were randomised (1:1) using sealed opaque envelopes to either CPAP or HFNC as their first-line mode of NRS. Consent was sought after randomisation in emergency situations. The primary study outcomes were related to feasibility (number of eligible patients in each group, proportion of eligible patients randomised, consent rate, and measures of adherence to study algorithms). Data were collected on safety and a range of patient outcomes in order to inform the choice of a primary outcome measure for the future RCT. RESULTS: Overall, 121/254 eligible patients (47.6%) were randomised (Group A 60%, Group B 44.2%) over a 10-month period (recruitment rate for Group A, 1 patient/site/month; Group B, 2.8 patients/site/month). In Group A, consent was obtained in 29/33 parents/guardians approached (87.9%), while in Group B 84/118 consented (71.2%). Intention-to-treat analysis included 113 patients (HFNC 59, CPAP 54). Most reported adverse events were mild/moderate (HFNC 8/59, CPAP 9/54). More patients switched treatment from HFNC to CPAP (Group A: 7/16, 44%; Group B: 9/43, 21%) than from CPAP to HFNC (Group A: 3/13, 23%; Group B: 5/41, 12%). Intubation occurred within 72 h in 15/59 (25.4%) of HFNC patients and 10/54 (18.5%) of CPAP patients (p = 0.38). HFNC patients experienced fewer ventilator-free days at day 28 (Group A: 19.6 vs. 23.5; Group B: 21.8 vs. 22.2). CONCLUSIONS: Our pilot trial confirms that, following minor changes to consent procedures and treatment algorithms, it is feasible to conduct a large national RCT of non-invasive respiratory support in the paediatric critical care setting in both step-up and step-down NRS patients. TRIAL REGISTRATION: clinicaltrials.gov, NCT02612415 . Registered on 23 November 2015.

Global perspective on training and staffing for paediatric cardiac critical care.

This manuscript provides a global perspective on physician and nursing education and training in paediatric cardiac critical care, including available resources and delivery of care models with representatives from several regions of the world including Africa, Israel, Asia, Australasia, Europe, South America, and the United States of America.

FIRST-line support for Assistance in Breathing in Children (FIRST-ABC): protocol for a multicentre randomised feasibility trial of non-invasive respiratory support in critically ill children.

INTRODUCTION: Over 18 000 children are admitted annually to UK paediatric intensive care units (PICUs), of whom nearly 75% receive respiratory support (invasive and/or non-invasive). Continuous positive airway pressure (CPAP) has traditionally been used to provide first-line non-invasive respiratory support (NRS) in PICUs; however, high-flow nasal cannula therapy (HFNC), a novel mode of NRS, has recently gained popularity despite the lack of high-quality trial evidence to support its effectiveness. This feasibility study aims to inform the design and conduct of a future definitive randomised clinical trial (RCT) comparing the two modes of respiratory support. METHODS AND ANALYSIS: We will conduct a three-centre randomised feasibility study over 12 months. Patients admitted to participating PICUs who satisfy eligibility criteria will be recruited to either group A (primary respiratory failure) or group B (postextubation). Consent will be obtained from parents/guardians prior to randomisation in 'planned' group B, and deferred in emergency situations (group A and 'rescue' group B). Participants will be randomised (1:1) to either CPAP or HFNC using sealed, opaque envelopes, from a computer-generated randomisation sequence with variable block sizes. The study protocol specifies algorithms for the initiation, maintenance and weaning of HFNC and CPAP. The primary outcomes are related to feasibility, including the number of eligible patients in each group, feasibility of randomising >50% of eligible patients and measures of adherence to the treatment protocols. Data will also be collected on patient outcomes (eg, mortality and length of PICU stay) to inform the selection of an appropriate outcome measure in a future RCT. We aim to recruit 120 patients to the study. ETHICS AND DISSEMINATION: Ethical approval was granted by the National Research Ethics Service Committee North East-Tyne&Wear South (15/NE/0296). Study findings will be disseminated through peer-reviewed journals, national and international conferences. TRIALS REGISTRATION NUMBER: NCT02612415; pre-results.

Midterm results of the Ross procedure in children: an appraisal of the subannular implantation with interrupted sutures technique.

OBJECTIVES: The support of the pulmonary autograft root by the fibromuscular left ventricular outflow tract is emphasized to address the concern related to the dilatation of the pulmonary autograft structures in the paediatric population. METHODS: This retrospective study analyses the outcomes of 75 children who were operated between 1998 and 2012 with the subannular interrupted sutures technique at a median age of 10.2 years (range, 5.3 months-18.0 years). Median follow-up time was 5.2 years (range, 3 days-13.2 years). RESULTS: There were no deaths, but there were 3 reinterventions on the autograft for regurgitation and 2 resections of left ventricular outflow tract obstruction. There was no significant autograft stenosis, and freedom from moderate-to-severe regurgitation was 95% (95% confidence interval: 89-100) and 88% (95% confidence interval: 77-99) at 5 and 10 years, respectively. Median z-scores at the latest follow-up examination were, at the annulus, 0.31 [interquartile range (IQR) = -0.81 to 1.2]; at the sinus of Valsalva, 2.7 (IQR = 1.5-3.5); and at the sinotubular junction, 3.1 (IQR = 1.7-4.2). The correlation between z-scores and time after the operation was negative at the level of the annulus (r = -0.29, P = 0.034) but positive at the level of the sinus (r = +0.37, P = 0.005) and the sinotubular junction (r = +0.26, P = 0.068). The median rate of change in the z-score at the annulus was low, 0.065 z-score/year (IQR = -0.13 to 0.43). CONCLUSIONS: The subannular interrupted sutures implantation technique is associated with acceptable risks and, in the midterm, delivers limited annular dilatation, autograft regurgitation and delayed need for autograft reintervention.

Heart failure from heart muscle disease in childhood: a 5-10 year follow-up study in the UK and Ireland.

AIMS: Our original study, the first national prospective study of new-onset heart failure from heart muscle disease in children, showed overall 1-year survival of 82%, and event (death or transplantation)-free survival of 66%. This study aimed to evaluate 5 + year outcomes of this important cohort. METHODS AND RESULTS: All centres in the UK and Ireland with 1-year event-free survivors participated (n = 14). Anonymised data based on last hospital attendance and echocardiograms were reviewed. The investigator was blinded to outcome at the time of echo review. Of sixty-nine 1-year event-free survivors, data were obtained on 64, with three lost to follow-up and two moved abroad. There were three deaths at 2.2, 3.3 and 9.0 years after presentation and one transplant, at 5.2 years. Overall/event-free survival was 77%/62% at 5 years and 73%/59% at 10 years, respectively. Overall and event-free survival conditional on 1-year survival was 94% at 5 years, and 89% at 10 years. For the 60 event-free survivors, median (range) follow-up duration was 9.04 (5.0-10.33) years for those still under review (n = 45), or time to discharge 5.25 (0.67-10.0) years (n = 15). Fifty-eight were in New York Heart Association (NYHA) Class 1, and two in Class 2. Forty-one out of sixty had normal echocardiograms at last follow-up. Predictors of better longer-term outcome were the same as for the original 1-year follow-up study, namely, younger age and higher fractional shortening measurement at presentation. CONCLUSIONS: Children who survive the first year following their first presentation with significant heart failure from heart muscle disease have a good longer-term outcome although there remains a small attrition rate.

Flecainide versus digoxin for fetal supraventricular tachycardia: Comparison of two drug treatment protocols.

BACKGROUND: The optimal treatment for fetal supraventricular tachycardia (SVT) with 1:1 atrioventricular relationship is unclear. OBJECTIVE: We compared the effectiveness of transplacental treatment protocols used in 2 centers. METHODS: Pharmacologic treatment was used in 84 fetuses. Maternal oral flecainide was the primary therapy in center 1 (n = 34) and intravenous maternal digoxin in center 2 (n = 50). SVT mechanism was classified by mechanical ventriculoatrial (VA) time intervals as short VA or long VA. Treatment success was defined as conversion to sinus rhythm (SR), or rate control, defined as >15% rate reduction. RESULTS: Short VA interval occurred in 67 fetuses (80%) and long VA in 17 (20%). Hydrops was present 28 of 84 (33%). For short VA SVT, conversion to SR was 29 of 42 (69%) for digoxin and 24 of 25 (96%) for flecainide (P = .01). For long VA SVT, conversion to SR and rate control was 4 of 8 (50%) and 0 of 8, respectively, for digoxin, and 6 of 9 (67%) and 2 of 9 (cumulative 89%) for flecainide (P = .13). In nonhydropic fetuses, digoxin was successful in 23 of 29 (79%) and flecainide in 26 of 27 (96%) (P = .10). In hydrops, digoxin was successful in 8 of 21 (38%), flecainide alone in 6 of 7 (86%, P = .07 vs digoxin), and flecainide ± amiodarone in 7 of 7 (100%) (P = .01). Intrauterine or neonatal death occurred in 9 of 21 hydropic fetuses treated with digoxin (43%), compared to 0 of 7 (P = .06) treated with flecainide. CONCLUSIONS: Flecainide was more effective than digoxin, especially when hydrops was present. No adverse fetal outcomes were attributed to flecainide.

Predictors and Outcome of Extracorporeal Life Support After Pediatric Heart Transplantation.

BACKGROUND: Extracorporeal life support (ECLS) has proven success after conventional cardiac surgery. Its use after pediatric heart transplantation is less well documented. We reviewed ECLS after pediatric heart transplantation, to understand better predisposing factors, morbidity, and mortality. METHODS: The notes of all patients at Great Ormond Street Hospital undergoing orthotopic heart transplantation from 1999 to 2009 were reviewed (202 transplants; patients aged 0.06 to 17.91 years). Patients were grouped by diagnosis: restrictive cardiomyopathy (n = 17), nonrestrictive cardiomyopathy (n = 134), and anatomic heart disease (n = 51). RESULTS: Twenty-eight patients (13.9%) required ECLS after transplantation. Those requiring ECLS had longer ischemic times (4.2 versus 3.7 hours, p = 0.02). More restrictive cardiomyopathy patients (35.3%) required ECLS-higher than dilated cardiomyopathy (10.4%) or anatomic heart disease (15.7%; χ(2) 7.99; p = 0.018). Factors associated with posttransplant ECLS were restrictive cardiomyopathy, longer ischemic time, and extracorporeal membrane oxygenation before transplant. Graft survival was higher in the non-ECLS group, with 1-year survival of 98.2% versus 57.7%; however, medium-term survival was comparable, with 5-year survival for those surviving to hospital discharge being 84.7% versus 100%. CONCLUSIONS: The requirement for ECLS was higher than expected for conventional cardiac surgery. Although just over one half of patients requiring ECLS survived to discharge, they had excellent medium-term survival, with all still alive. Although ECLS is an expensive, invasive therapy, with significant morbidity and mortality, without it, those patients would have perished. Its judicious use, therefore, can be recommended.

Performance monitoring of the arterial switch operation: a moving target.

OBJECTIVES: Twenty years ago our institution published an analysis of a cluster of failures associated with the arterial switch operation (ASO). The concept of 'near miss' was explored to detect warning signs of suboptimal performance. The aim of the current study was to review the parameters best suited to monitoring early ASO outcomes in the modern setting and re-examine the concept of near misses as failure equivalents. METHODS: All ASOs performed in our institution between 1983 and 2012 were reviewed. The experience was divided into three eras (1983-92, 1993-2002 and 2003-12). The cumulative sum graphic for sequential monitoring was used for early mortality. The need to re-establish cardiopulmonary bypass (CPB), CPB time >240 min and extracorporeal membrane oxygenation (ECMO) were explored as variables of near misses. RESULTS: The cohort consisted of 606 patients. The 30-day mortality rate was 23% (n = 29) in Era 1, 6% (n = 14) in Era 2 and 1% (n = 3) in Era 3. There were further 4, 8 and 6 deaths between 30 and 90 days in the three eras, respectively. In Era 3, the majority of deaths occurred between 30 and 90 days. In the current era, ECMO and CPB time >240 min as a marker of near miss was associated with an increased risk of death both within 30 days and 90 days after ASO. CONCLUSIONS: The 30-day outcomes of ASO have significantly improved over the last 30 years. As life-saving mechanical support after surgery has been implemented more often, an extended 90-day window of reporting can offer a more realistic outcome indicator of performance.

Longer hospital stay after Fontan completion in the November to March period.

OBJECTIVES: Initial evidence suggests that total cavopulmonary connection (TCPC) completion during winter is associated with prolonged pleural effusion and hospitalization. This study was carried out to review the impact of season of operation on short-term outcome after TCPC procedure. METHODS: We conducted a retrospective study on 104 consecutive patients who underwent the extracardiac TCPC procedure from June 2006 to November 2011 (mean age 5.0 ± 2.6 years, 60 males). The outcomes of interest assessed were length of postoperative hospital stay (LOS) and duration of pleural drainage. These were adjusted to potential, known standard Fontan risk factors such as age, ventricular morphology, cardiac function and previous surgical history. Length of chest drainage and LOS in the period November-March (NM) was compared with that in the period April-October (AO). RESULTS: Of the 104 patients, 6 patients were excluded since they either required early reoperation or were transferred to another institution for their postoperative care. The group included 26 children with hypoplastic left heart syndrome. Thirty-four of the 98 remaining patients (34.7%) had surgery in the NM period. Overall, length of pleural drainage was 9 days (interquartile range 6-13) and LOS was 12 days (9-17). TCPC surgery in the NM period (P = 0.045), male gender (P = 0.020) and right ventricular morphology (P = 0.034) were the only variables associated with prolonged LOS at univariate analysis; no other factor including ventricular function, Glenn pressure, weight and age at operation were associated with LOS. NM surgery was the only predictor of LOS at multivariate analysis (P = 0.045). Patients with surgery in the NM period had a higher incidence of low cardiac output/acute renal dysfunction postoperatively (26.5 vs 9.4%, P = 0.038) and a higher incidence of infections requiring antibiotic use (64.7 vs 32.8%, P = 0.003). CONCLUSIONS: TCPC surgery performed in the period between November and March is associated with increased morbidity, especially longer hospitalization. Given the elective nature of TCPC operation, this operation should be scheduled outside of the NM period if possible.