Cardiovascular magnetic resonance in children with suspected myocarditis: current practice and applicability of adult protocols.

BACKGROUND: Cardiovascular magnetic resonance serves as a useful tool in diagnosing myocarditis. Current adult protocols are yet to be validated for children; thus, it remains unclear if the methods used can be applied with sufficient image quality in children. This study assesses the use of cardiovascular magnetic resonance in children with suspected myocarditis. METHODS: Image data from clinical cardiovascular magnetic resonance studies performed in children enrolled in Mykke between June 2014 and April 2019 were collected and analysed. The quality of the data sets was evaluated using a four-point quality scale (4: excellent, 3: good, 2: moderate, 1: non-diagnostic). RESULTS: A total of 102 patients from 9 centres were included with a median age (interquartile range) of 15.4(10.7-16.6) years, 137 cardiovascular magnetic resonance studies were analysed. Diagnostic image quality was found in 95%. Examination protocols were consistent with the original Lake Louise criteria in 58% and with the revised criteria in 35%. Older patients presented with better image quality, with the best picture quality in the oldest age group (13-18 years). Sedation showed a negative impact on image quality in late gadolinium enhancement and oedema sequences. No such correlation was seen in cardiac function assessment sequences. In contrast to initial scans, in follow-up examinations, the use of parametric mapping increased while late gadolinium enhancement and oedema sequences decreased. CONCLUSION: Cardiovascular magnetic resonance protocols for the assessment of adult myocarditis can be applied to children without significant constraints in image quality. Given the lack of specific recommendations for children, cardiovascular magnetic resonance protocols should follow recent recommendations for adult cardiovascular magnetic resonance.

Severe heart failure and the need for mechanical circulatory support and heart transplantation in pediatric patients with myocarditis: Results from the prospective multicenter registry "MYKKE".

Myocarditis represents an important cause for acute heart failure. MYKKE, a prospective multicenter registry of pediatric patients with myocarditis, aims to gain knowledge on courses, diagnostics, and therapy of pediatric myocarditis. The role of mechanical circulatory support (MCS) in children with severe heart failure and myocarditis is unclear. The aim of this study was to determine characteristics and outcome of patients with severe heart failure requiring MCS and/or heart transplantation. The MYKKE cohort between September 2013 and 2016 was analyzed. A total of 195 patients were prospectively enrolled by 17 German hospitals. Twenty-eight patients (14%) received MCS (median 1.5 years), more frequently in the youngest age group (0-2 years) than in the older groups (P < 0.001; 2-12 and 13-18 years). In the MCS group, 50% received a VAD, 36% ECMO, and 14% both, with a survival rate of 79%. The weaning rate was 43% (12/28). Nine (32%) patients were transplanted, one had ongoing support, and six (21%) died. Histology was positive for myocarditis in 63% of the MCS group. Patients within the whole cohort with age <2 years and/or ejection fraction <30% had a significantly worse survival with high risk for MCS, transplantation, and death (P < 0.001). Myocarditis represents a life-threatening disease with an overall mortality of 4.6% in this cohort. The fulminant form more often affected the youngest, leading to significantly higher rate of MCS, transplantation, and mortality. MCS represents an important and life-saving therapeutic option in children with myocarditis with a weaning rate of 43%.

Implementing and Assessing a Standardized Protocol for Weaning Children Successfully From Extracorporeal Life Support.

Extracorporeal life support (ECLS) weaning is a complex interdisciplinary process with no clear guidelines. To assess ventricular and pulmonary function as well as hemodynamics including end-organ recovery during ECLS weaning, we developed a standardized weaning protocol. We reviewed our experience 2 years later to assess its feasibility and efficacy. In 2015 we established an inter-professional, standardized, stepwise protocol for weaning from ECLS. If the patient did not require further surgery, weaning was conducted bedside in the intensive care unit (ICU). Most of the weaning procedures are guided via echocardiography. Data acquisition began at baseline level, followed by four-step course (each step lasting 10 min), entailing flow-reduction and ending 30 min after decannulation. Moreover, data from the preprotocol era are presented. Between May 2015 and 2017, 26 consecutive patients (18 male), median age 177 days (2 days-20 years) required ECLS with median support of 4 (2-11) days. Excluding eight not weanable patients, 21 standardized weaning procedures were protocolled in the remaining 18 children. Our generally successful protocol-guided weaning rate (with at least 24-h survival) was 89%, with a discharge home rate of 58%. Practical application of the novel standard protocol seems to facilitate ECLS weaning and to improve its success rate. The protocol can be administered as part of standard bedside ICU assessment.

Echocardiographic characteristics in Fontan patients before the onset of protein-losing enteropathy or plastic bronchitis.

BACKGROUND: It was this study's objective to evaluate the echocardiographic characteristics and flow patterns in abdominal arteries of Fontan patients before the onset of protein-losing enteropathy (PLE) or plastic bronchitis (PB). DESIGN: In this retrospective cohort investigation, we examined 170 Fontan patients from 32 different centers who had undergone echocardiographic and Doppler ultrasound examinations between June 2006 and May 2013. Follow-up questionnaires were completed by 105 patients a median of 5.3 (1.5-8.5) years later to evaluate whether one of the complications had occurred since the examinations. RESULTS: A total of 91 patients never developed PLE or PB ("non-PLE/PB"); they were compared to 14 affected patients. Eight of the 14 patients had already been diagnosed with "present PLE/PB" when examined. Six "future PLE/PB" patients developed those complications later on and were identified on follow-up. The "future PLE/PB" patients presented significantly slower diastolic flow velocities in the celiac artery (0.1 (0.1-0.5) m/s vs 0.3 (0.1-1.0) m/s (P = .04) and in the superior mesenteric artery (0.0 (0.0-0.2) m/s vs 0.2 (0.0-0.6) m/s, P = .02) than the "non-PLE/PB" group. Median resistance indices in the celiac artery were significantly higher (0.9 (0.8-0.9) m/s vs 0.8 (0.6-0.9) m/s, (P = .01)) even before the onset of PLE or PB. CONCLUSION: An elevated flow resistance in the celiac artery may prevail in Fontan patients before the clinical manifestation of PLE or PB.

R-wave synchronised atrial pacing in post-operative junctional ectopic tachycardia using a transoesophageal pacemaker.

We report the first case of R-wave synchronised atrial pacing using a transoesophageal pacemaker. A 3-month-old baby developed a junctional ectopic tachycardia after surgical closure of a ventricular septal defect. R-wave synchronised atrial pacing with an external pacemaker was not possible owing to dislocation of the atrial epimyocardial pacing wires. Therefore, a temporary oesophageal pacemaker was connected in series to the external pacemaker to allow transoesophageal atrial pacing triggered by the preceding ventricular actions.

The Yasui procedure with a modified right ventricle-to-pulmonary artery connection utilizing autologous left atrial appendage as a free graft.

A 9-month-old girl born with an interrupted aortic arch type B, an arteria lusoria (aberrant right subclavian artery) and a multilevel left ventricular outflow tract obstruction underwent a Yasui completion after an initial interim palliation. After the Damus-Kaye-Stansel procedure was carried out and the Sano shunt had been established as a source of pulmonary flow, the reported procedure comprised closure of the ventricular septal defect and the intraventricular baffling of left ventricular outflow through a malaligned ventricular septal defect, incision and partial resection of a conal septum and establishment of a right ventricle-to-pulmonary artery connection using an autologous left atrial appendage as a free graft. This technique consisted of dissecting and harvesting the left atrial appendage, which was then used as autologous material for an interposition plasty connecting the central pulmonary artery bifurcation segment with the upper rim of the infundibulotomy. Native, autologous tissue thus comprised the backwall of the newly created right ventricle-to-pulmonary artery continuity. Porcine pericardial patch plasty was then used to complete the remaining circumference of the right ventricle-to-pulmonary artery continuity.

Benefit From a Humanitarian Pediatric Congenital Heart Surgery Program Over a 10-Year Period.

Background: The charity organization Kinderherzen retten e.V. (KHR) enables humanitarian congenital heart surgery for pediatric patients from low- and middle-income countries at the University Heart Center Freiburg, Germany. The aim of this study was to assess periprocedural and mid-term outcomes of these patients for evaluation of KHR sustainability. Methods: Part one of the study comprised retrospective medical chart analyses of the periprocedural course of all KHR-treated children from 2008 to 2017, and part two a prospective evaluation of their mid-term outcome, assessed by questionnaires concerning survival, medical history, mental and physical development, and socioeconomic situation. Results: Of the 100 consecutively presented children from 20 countries (median age 3.25 years), 3 patients were not invasively treatable, 89 underwent cardiovascular surgery, and 8 received a catheter intervention only. There were no periprocedural deaths. Median postoperative duration of mechanical ventilation, intensive care stay, and total hospital stay was 7 (interquartile range [IQR] 4-21) hours, 2 (IQR 1-3) days, and 12 (IQR 10-16) days, respectively. Mid-term postoperative follow-up demonstrated a 5-year survival probability of 94.4%. The majority of patients received continued medical care in their home country (86.2% of patients), were in good mental and physical condition (96.5% and 94.7% of patients, respectively), and able to engage in age-appropriate education/employment (98.3% of patients). Conclusions: Cardiac, neurodevelopmental, and socioeconomic outcomes of patients treated via KHR was satisfactory. Thorough pre-visit evaluation and close contact with local physicians are crucial when providing this high-quality, sustainable, and viable therapeutic option for these patients.

Clinical characteristics and outcome of biopsy-proven myocarditis in children - Results of the German prospective multicentre registry "MYKKE".

BACKGROUND: Heart failure (HF) due to myocarditis might not respond in the same way to standard therapy as HF due to other aetiologies. The aim of this study was to investigate the value of endomyocardial biopsies (EMB) for clinical decision-making and its relation to the outcome of paediatric patients with myocarditis. METHODS: Clinical and EMB data of children with myocarditis collected for the MYKKE-registry between 2013 and 2020 from 23 centres were analysed. EMB studies included histology, immunohistology, and molecular pathology. The occurrence of major adverse cardiac events (MACE) including mechanical circulatory support (MCS), heart transplantation, and/or death was defined as a combined endpoint. RESULTS: Myocarditis was diagnosed in 209/260 patients: 64% healing/chronic lymphocytic myocarditis, 23% acute lymphocytic myocarditis (AM), 14% healed myocarditis, no giant cell myocarditis. The median age was 12.8 (1.4-15.9) years. Time from symptom-onset to EMB was 11.0 (4.0-29.0) days. Children with AM and high amounts of mononuclear cell infiltrates were significantly younger with signs of HF compared to those with healing/chronic or healed myocarditis. Myocardial viral DNA/RNA detection had no significant effect on outcome. The worst event-free survival was seen in patients with healing/chronic myocarditis (24%), followed by acute (31%) and healed myocarditis (58%, p = 0.294). A weaning rate of 64% from MCS was found in AM. CONCLUSIONS: EMB provides important information on the type and stage of myocardial inflammation and supports further decision-making. Children with fulminant clinical presentation, high amounts of mononuclear cell infiltrates or healing/chronic inflammation and young age have the highest risk for MACE.

Ex Vivo Allograft Perfusion for Complex Pediatric Heart Transplant Recipients.

BACKGROUND: Pediatric heart transplant (HTx) recipients with congenital heart defects require complex concomitant surgical procedures with the risk of prolonging the allograft's ischemic time. Ex vivo allograft perfusion with the Organ Care System (OCS; Transmedics, Andover, MA) may improve survival of these challenging patients. METHODS: In this retrospective, single-center study a consecutive series of 8 children with allografts preserved using the OCS was compared with 13 children after HTx with cold storage of the donor heart from March 2018 to March 2020. RESULTS: Median recipient age in the control group was 18 months (range, 1-189) versus 155 months (range, 83-214) in the OCS group, and the baseline differences between the 2 groups were not significant. Fifty percent of the children in the OCS group had complex congenital heart defects (vs 15% of the control subjects). Median operation time during HTx in the OCS group was 616 minutes (range, 270-809) versus 329 minutes (range, 283-617). Because of the time of ex vivo allograft perfusion (265 minutes [range, 202-372]) median total ischemia time was significantly shorter in the OCS group: 78 minutes (range, 52-111) versus 222 minutes (range, 74-326). The incidence of primary graft, renal, or hepatic failure did not differ between the groups. Graft function and the occurrence of any treated rejection at follow-up revealed no significant difference between the 2 groups. One-year survival was 88% in the OCS group (vs 85%). CONCLUSIONS: Ex vivo allograft perfusion enabled complex pediatric HTx, yielding outcomes as positive as those of children whose donor hearts were stored in ice-cold solution.

Retrograde transcatheter aortic valve closure in an infant with failing Norwood stage I palliation: a case report.

BACKGROUND: Aortic valve regurgitation leading to coronary steal phenomenon can severely impair cardiac function in hypoplastic left heart syndrome, thus worsening long-term outcome. CASE PRESENTATION: A German infant with borderline aortic and mitral valve, hypoplastic left ventricle, ventricular septal defect, and hypoplastic aortic arch with critical coarctation initially underwent aortic arch reconstruction and aortic valve dilation with the aim of biventricular correction later on. Unfortunately, severe cardiac dysfunction necessitated a change in strategy entailing modified stage I Norwood palliation. Increasing aortic regurgitation with coronary steal was revealed postoperatively, which required redo surgery to oversew the valve. However, pronounced aortic regurgitation recurred, causing severe cardiac decompensation with repeated resuscitation. As a bailout strategy, we performed aortic valve closure via transfemoral retrograde implantation of an Amplatzer Duct Occluder II device. This led to the patient's rapid stabilization while circumventing highly risky renewed surgery in such a critically ill infant. CONCLUSIONS: Retrograde transcatheter aortic valve closure may be considered a feasible alternative in infants with a failing single ventricle due to aortic regurgitation, with critical device evaluation being crucial for successful device implantation in this young age group.

Cor triatriatum sinistrum in childhood. A single institution's experience.

INTRODUCTION: Cor triatriatum sinistrum (CTS) is a rare congenital cardiac defect that can present with a wide range of symptoms and may be associated with other structural cardiac defects. Very limited data are available for pediatric patients. OBJECTIVE: To analyze the experience with CTS at a single pediatric centre, highlighting symptoms on presentation, mode of diagnosis and outcome. METHODS: Hospital databases were searched to identify patients with CTS who were diagnosed between 1954 and 2005. Medical records with demographic data, clinical evaluation, diagnostic approach, interventions and autopsy results were reviewed. RESULTS: Between 1954 and 2005, 82 patients (43 female children, 52%) with CTS were diagnosed at the institution. Patients were born between 1951 and 2004, and the median age at presentation was eight months (range one day to 16.1 years). The majority of patients (77%) presented with associated cardiac lesions. Of 82 patients, 57 (70%) underwent resection of the fibromuscular diaphragm, 14 (17%) did not require surgery and 11 (13%) did not survive the time to intervention. Nineteen patients (23%) died a median of two months (range one day to 5.5 years) after presentation. Nine of these patients (11%) died before surgery was attempted. Most patients were completely asymptomatic at the time of the last follow-up at a median of three years (range one day to 18 years). Echocardiography significantly facilitated the diagnosis and subsequent management of patients with CTS. CONCLUSIONS: Despite the diversity in presentation and complexity of associated lesions, the outcome for patients with CTS is favourable.