Growing up with a pacemaker

 

Indications for pacemakers in young children are rare. In our university hospitals, on average 8 patients/year received a pacemaker in this age group between 2001 and 2015 for a drainage area of 4 million people. In 28% this is for congenital heart block and in 69% for bradycardia after surgical repair of congenital structural heart disease. Despite the extensive range of patient information about pacemakers, we felt a need for targeted material for young patients, who have an indication for a pacemaker, and their family. We wanted to provide this information to this specific group in a creative, accessible and clear way, taking into account their way of thinking. In addition, we also wanted to involve the near and wider environment of the child (family, school, sports club, etc.), and to provide them with tools to better deal with the medical situation.

For the little children we created a stop-motion story in which sinus node disease (SND) and AV block (AVB) are represented by a character: Bob Sparkle (Bob Prikkel in Dutch for SND) and Boris Sparkle (Boris Prikkel for AVB). Bob and Boris get into trouble and are rescued by Pacemaker, the third character in the films. This story is preceded by an informative part for parents and older children in which the normal functioning and conduction system of the heart is explained. Based on the films, we designed customized information brochures for +12 and −12 year-old children. The brochure for +12 includes the same information as the adult version, but in more comprehensible language. The figures Bob and Boris were added throughout this brochure as a sort of common thread. For the −12 group we designed 2 reading books in which the story of Bob / Boris is told. The −12 booklets can be included in a cover along with the +12 brochure, so that the parents can estimate for themselves what is most suitable for their child.

We conducted a survey on how this information was received by patients and their relatives.61 families were contacted by e-mail to fill in a questionnaire using a 5-point Likert Scale. The survey assessed the following three items: graphic design, intelligibility and aid in coping with illness. Currently we have received answers from 12 patients or their relatives.

Overall, there was a positive reception of the different informative tools (agree or strongly agree: booklets: 92.6%; brochure: 77.2%; films: 81.3%).

Funding Acknowledgement

Type of funding source: None

Infective endocarditis in patients after percutaneous pulmonary valve implantation with the stent-mounted bovine jugular vein valve: Clinical experience and evaluation of the modified Duke criteria

AIMS

Percutaneous pulmonary valve implantation (PPVI) has proven good hemodynamic results. As infective endocarditis (IE) remains a potential complication with limited available clinical data, we reviewed our patient records to improve future strategies of IE prevention, diagnosis and treatment.

METHODS

Medical records of all patients diagnosed with Melody® valve IE according to the modified Duke criteria were retrospectively analyzed in three Belgian tertiary centers.

RESULTS

23 IE episodes in 22 out of 240 patients were identified (incidence 2.4% / patient year) with a clear male predominance (86%). Median age at IE was 17.9 years (range 8.2-45.9 years) and median time from PPVI to IE was 2.4 years (range 0.7-8 years). Streptococcal species caused 10 infections (43%), followed by Staphylococcus aureus (n = 5, 22%). In 13/23 IE episodes a possible entry-point was identified (57%). IE was classified as definite in 15 (65%) and as possible in 8 (35%) cases due to limitations of imaging. Echocardiography visualized vegetations in only 10 patients. PET-CT showed positive FDG signals in 5/7 patients (71%) and intracardiac echocardiography a vegetation in 1/1 patient (100%). Eleven cases (48%) had a hemodynamically relevant pulmonary stenosis at IE presentation. Nine early and 6 late percutaneous or surgical re-interventions were performed. No IE related deaths occurred.

CONCLUSIONS

IE after Melody® valve PPVI is associated with a relevant need of re-interventions. Communication to patients and physicians about risk factors is essential in prevention. The modified Duke criteria underperformed in diagnosing definite IE, but inclusion of new imaging modalities might improve diagnostic performance.

Application of a postnatal prediction model of survival in CDH in the era of fetal therapy

Background: The disease severity in patients with a congenital diaphragmatic hernia (CDH) is highly variable. To compare patient outcomes, set up clinical trials and come to severity-based treatment guidelines, a performant prediction tool early in neonatal life is needed.Objective: The primary purpose of this study was to validate the CDH study group (SG) prediction model for survival in neonates with CDH, including patients who had fetal therapy. Secondary, we aimed to assess its predictive value for early morbidity.Methods: This is a retrospective single-center study at the University Hospitals Leuven on all infants with a diagnosis of CDH live-born between April 2002 and December 2016. The prediction model of the CDHSG was applied to evaluate its performance in determining mortality risk. Besides, we examined its predictive value for early morbidity parameters, including duration of ventilation, respiratory support on day 30, time to full enteral feeding and length of hospital stay.Results: The CDHSG prediction model predicted survival well, with an area under the curve of 0.796 (CI: 0.720-0.871). It had poor value in predicting infants who needed respiratory support on day 30 (area under the curve (AUC) 0.606; CI: 0.493-0.719), and correlated poorly with duration of ventilation, time to full enteral feeding and length of hospital stay.Conclusion: The CDHSG prediction model was in our hands also a useful tool in predicting mortality in neonates with CDH in the fetal treatment era. Correlation with early morbidity was poor.RationaleObjectives: (1) Validation of the CDHSG prediction model for survival in a cohort of neonates with CDH, in whom fetal endoscopic tracheal occlusion was applied according to the severity of lung hypoplasia. (2) Evaluation of performance of the model in the prediction of early morbidity.Main results: (1) Confirmation of the predictive value of the model for survival in neonates with CDH in the era of fetal therapy. (2) No correlation of the model with early morbidity parameters.

Differences in Copy Number Variation between Discordant Monozygotic Twins as a Model for Exploring Chromosomal Mosaicism in Congenital Heart Defects

Studies addressing the role of somatic copy number variation (CNV) in the genesis of congenital heart defects (CHDs) are scarce, as cardiac tissue is difficult to obtain, especially in non-affected individuals. We explored the occurrence of copy number differences in monozygotic (MZ) twins discordant for the presence of a CHD, as an illustrative model for chromosomal mosaicism in CHDs. Array comparative genomic hybridization was performed on peripheral blood-derived DNA obtained from 6 discordant MZ twin pairs and on sex-matched reference samples. To identify CNV differences between both twin members as well as potential CNVs in both twins contributing to the phenotype, DNA from each twin was hybridized against its co-twin, and against a normal control. Three copy number differences in 1 out of 6 MZ twin pairs were detected, confirming the occurrence of somatic CNV events in MZ twins. Further investigation by copy number and (epi)genome sequencing analyses in MZ twins, discordant for the presence of CHDs, is required to improve our knowledge on how postzygotic genetic, environmental and stochastic factors can affect human heart development.

Progressive myoclonic epilepsy as an adult-onset manifestation of Leigh syndrome due to m.14487T>C

BACKGROUND

m.14487T>C, a missense mutation (p.M63V) affecting the ND6 subunit of complex I of the mitochondrial respiratory chain, has been reported in isolated childhood cases with Leigh syndrome (LS) and progressive dystonia. Adult-onset phenotypes have not been reported.

OBJECTIVES

To determine the clinical-neurological spectrum and associated mutation loads in an extended m.14487T>C family.

METHODS

A genotype-phenotype correlation study of a Belgian five-generation family with 12 affected family members segregating m.14487T>C was carried out. Clinical and mutation load data were available for nine family members. Biochemical analysis of the respiratory chain was performed in three muscle biopsies.

RESULTS

Heteroplasmic m.14487T>C levels (36-52% in leucocytes, 97-99% in muscle) were found in patients with progressive myoclonic epilepsy (PME) and dystonia or progressive hypokinetic-rigid syndrome. Patients with infantile LS were homoplasmic (99-100% in leucocytes, 100% in muscle). We found lower mutation loads (between 8 and 35% in blood) in adult patients with clinical features including migraine with aura, Leber hereditary optic neuropathy, sensorineural hearing loss and diabetes mellitus type 2. Despite homoplasmic mutation loads, complex I catalytic activity was only moderately decreased in muscle tissue.

INTERPRETATION

m.14487T>C resulted in a broad spectrum of phenotypes in our family. Depending on the mutation load, it caused severe encephalopathies ranging from infantile LS to adult-onset PME with dystonia. This is the first report of PME as an important neurological manifestation of an isolated mitochondrial complex I defect.

Post-catheterization pseudoaneurysm in a one-year-old child treated by ultrasound-guided human thrombin injection

We report a successful treatment of iatrogenic post-catheterization pseudoaneurysm of the right common femoral artery in a one-year-old boy with ultrasound-guided percutaneous injection of human thrombin under general anesthesia. Physical examination after 2 months follow-up showed complete disappearance of the pulsating lump.

Radiation dose survey in a paediatric cardiac catheterisation laboratory equipped with flat-panel detectors

Flat-panel X-ray detectors for fluoroscopy represent a modern imaging equipment that is being implemented in paediatric cardiac catheterisation laboratories. Infants and children represent a group of patients with a high radiosensitivity. A survey of 273 (126 diagnostic and 147 therapeutic) paediatric catheterisations was performed to investigate the radiation doses delivered by the new X-ray system. Statistical parameters (75th, 50th and 25th percentiles) of dose-area product (DAP) and fluoroscopy time are reported for patients divided into six age groups: 0-30 d, >1-12 m, >1-3, >3-5, >5-10 and >10-15 y. For accurate risk estimation, effective dose (E) has been determined for all patients using the PCXMC software. For diagnostic procedures, the third quartile of E ranges from 11.3 mSv for newborns to 7 mSv for children of 10-15 y. Therapeutic procedures are more complex than diagnostic. Consequently, the third quartile of E is 22.6 mSv (0-30 d), 18.6 (>1-12 m), 13.3 (>1-3 y), 21.5 (>3-5 y), 17.8 (>5-10 y) and 34.1 mSv (>10-15 y). Dose conversion factors, which relate the DAP and E, have been estimated for each age group. The results of this study may serve as a first step in the optimisation process, in order to make full use of the dose reduction potential of flat-panel systems.

Intellectual abilities in a large sample of children with Velo-Cardio-Facial Syndrome: an update

BACKGROUND

Learning disabilities are one of the most consistently reported features in Velo-Cardio-Facial Syndrome (VCFS). Earlier reports on IQ in children with VCFS were, however, limited by small sample sizes and ascertainment biases. The aim of the present study was therefore to replicate these earlier findings and to investigate intellectual abilities in a large sample of children with VCFS. In addition, we aimed to identify factors that may contribute to within-syndrome variability in cognitive performance, such as the mode of inheritance of the deletion, sex, the presence of a heart defect and psychiatric morbidity.

METHOD

IQ data of 103 children with VCFS (56 males, 47 females) were collected. Psychiatric diagnosis was additionally recorded.

RESULTS

Children with VCFS had a mean full-scale IQ (FSIQ) of 73.48 (range: 50-109). There were no effects of sex, presence of a heart defect and psychiatric condition on intellectual profile. Inheritance of the deletion affected cognitive performance in VCFS, with children with familial deletions having significant lower FSIQ than children with a de novo deletion.

CONCLUSIONS

Learning disabilities are very common in children with VCFS, although marked within syndrome variability is noted. One factor contributing to this variability seems to be the mode of inheritance of the deletion.

Efficiency of oxygen cost during exercise in patients with symptoms of fatigue during physical activities

BACKGROUND

With growing age, values for oxygen uptake decrease for the same level of exercise. However, some children with normal heart and normal maximal oxygen uptake complain of exertional fatigue.

AIM

To evaluate the energy expenditure during submaximal treadmill exercise.

SUBJECTS AND METHODS

In 20 children with exertional fatigue (mean age at testing: 7.9 +/- 1.8 years), oxygen uptake and respiratory gas exchange were assessed breath by breath. A graded exercise test was performed until exhaustion. Patients were compared to an age- and gender-matched control group (8.4 +/- 1.9 years, p = 0.45).

RESULTS

Maximal oxygen uptake in patients (48.6 +/- 7.1 mL O(2)/min/kg) was similar to normal controls (47.4 +/- 5.2 mL/min/kg, p > 0.25). The inclination of the treadmill at maximal exercise was significantly (p = 0.02) lower in patients (12.6 +/- 4.9%) versus controls (16.0 +/- 3.5%). During submaximal exercise, oxygen uptake (expressed as mL/min/kg or as a percent of maximal oxygen uptake) was significantly higher (p < 0.001) in patients compared to normal controls.

CONCLUSION

Children with exertional fatigue as compared to healthy controls, have a higher oxygen uptake for the same level of exercise and therefore perform at each level of exercise closer to their maximal exercise capacity. This may in part explain subjective complaints of poor exercise tolerance.

Molecular cytogenetic characterization of a constitutional complex intrachromosomal 4q rearrangement in a patient with multiple congenital anomalies

Constitutional Complex Chromosomal Rearrangements (CCRs) are very rare. While the vast majority of CCRs involve more than one chromosome, only seven cases describe CCRs with four or more breakpoints within a single chromosome. Here, we present a patient with multiple congenital anomalies and mental retardation. Array Comparative Genomic Hybridisation (array CGH), FISH and Multicolour Banding FISH revealed a de novo complex rearrangement with two deletions, a duplication and an inversion of 4q. This CCR involving at least seven breakpoints is one of the most complex rearrangements of a single chromosome reported thus far. Potential mechanisms generating such complex rearrangements are discussed.

Stenting of hypoplastic aortic segments with mild pressure gradients and arterial hypertension

OBJECTIVE

To determine the safety, feasibility and effectiveness of stent expansion of hypoplastic aortic segments with pressure gradients in patients with arterial hypertension.

DESIGN

Non-randomised prospective clinical trial.

SETTING

Tertiary referral centre, congenital cardiac unit.

PATIENT SELECTION

20 consecutive patients (median age 14.5 years, range 11.6-38.8 years) with arterial hypertension and a hypoplastic segment of the aorta. Seventeen patients had successful previous arch interventions in a coarctation site.

INTERVENTIONS

Stent deployment in hypoplastic arch segments.

MAIN OUTCOME MEASURES

Gradient across the aortic arch; complications early and during follow up; residual hypertension.

RESULTS

23 stents were deployed: 13 in the cross and 10 in the isthmus. The mean gradient across the aortic arch decreased from 16 (SD 6) (median 17) to 3 (4) (median 1) mm Hg (p < 0.001). In a few patients a mild gradient persisted just distal to the left carotid artery due to residual orificial narrowing or acute angulation. No complications occurred during or after the procedure. During follow up of 2.2 years (range 0.2-4.8 years) arterial hypertension resolved in 10 patients and 10 required residual drug treatment with better control of blood pressures.

CONCLUSIONS

Pressure loss due to residual hypoplastic aortic segments can be treated effectively and safely with stent expansion. Some patients remain mildly hypertensive and require additional drug treatment.

Late fenestration of the extracardiac conduit in a Fontan circuit by sequential stent flaring

Recent Fontan circuits frequently involve an extracardiac conduit. We report on a new technique to create a late fenestration in such an extracardiac circuit by sequential flaring of a stent in the fenestration.

Changes in perceived health of children with congenital heart disease after attending a special sports camp

Sports camps for children with cardiac anomalies have existed for many years. However, no formal evaluation of the benefits of attending such camps has been undertaken heretofore. We assessed potential changes in the self-perceived health of children with congenital heart disease who attended a special sports camp. Thirty-one children with cardiac anomalies attended a 3-day multisports camp. Sixteen children, all of whom were 10 years or older, literate, and Dutch- or French-speaking, completed the Child Health Questionnaire (CHQ-CF87) before and after attending the camp. The scores of the children were compared with those of healthy peers by calculating mean standardized differences. After attendance at the sports camp, the children achieved significant improvements in the self-perception of their physical functioning, role functioning due to emotional problems, role functioning due to behavioral problems, mental health, and general behavior. The children's self-esteem and general behavior after the camp were significantly better than that of their healthy counterparts. We conclude that children with congenital heart disease who participate in activities at special sports camps may reap benefits in terms of their subjective health status. Although further research is needed, we recommend the participation in sport activities by children with heart defects, and more specifically their participation in sports camps.

Is the severity of congenital heart disease associated with the quality of life and perceived health of adult patients?

OBJECTIVE

To explore whether the severity of congenital heart disease is associated with the quality of life and perceived health status of adult patients.

DESIGN

Descriptive, cross sectional study.

SETTING

Adult congenital heart disease programme in one tertiary care centre in Belgium.

PATIENTS

629 patients (378 men, 251 women) with a median age of 24 years.

MAIN OUTCOME MEASURES

Disease severity was operationalized in terms of initial diagnosis (classification of Task Force 1 of the 32nd Bethesda Conference), illness course (disease severity index), and current functional status (New York Heart Association (NYHA) class, ability index, congenital heart disease functional index, and left ventricular ejection fraction). Quality of life was measured by a linear analogue scale, the satisfaction with life scale, and the schedule for evaluation of individual quality of life. Perceived health status was also assessed with a linear analogue scale.

RESULTS

Scores derived from the disease severity classification systems were weakly negatively associated with quality of life and health status, ranging from -0.05 to -0.27. The NYHA functional class and ability index were consistently associated with quality of life and perceived health.

CONCLUSIONS

This study showed that the severity of congenital heart disease is marginally associated with patients' quality of life and perceived health. Functional status was more related to patients' assessment of their quality of life than was the initial diagnosis or illness course.

Long term outcome up to 30 years after the Mustard or Senning operation: a nationwide multicentre study in Belgium

OBJECTIVE

To assess long term outcome of patients who underwent Mustard or Senning repair for transposition of the great arteries up to 30 years earlier.

DESIGN

Retrospective review of medical records.

SETTING

The six university hospitals in Belgium with paediatric cardiology departments.

PATIENTS

339 patients were reviewed, of whom 124 underwent the Mustard procedure and 215 the Senning procedure. This represents almost the entire population of patients in Belgium with either simple or complex transposition.

MAIN OUTCOME MEASURES

Mortality, morbidity, functional abilities, social integration.

RESULTS

Overall mortality was 24.2%. Early mortality (< or = 30 days after surgery) accounted for 16.5%, late mortality for 7.7%. Actuarial survival of early survivors at 10, 20, and 30 years after surgery was 91.7%, 88.6%, and 79.3%, respectively. Patients in the Senning cohort had a slightly better survival rate than those in the Mustard cohort (NS). Baffle obstruction occurred more often after Mustard repair (15.3%) than after the Senning procedure (1.4%). Arrhythmia-free survival did not differ between the two cohorts, but was determined by the complexity of the transposition. Survivors of the Senning cohort had better functional status, and tended to engage in more sports activities.

CONCLUSIONS

The long term outcome for patients surviving the Mustard or Senning operation was favourable in terms of late mortality, morbidity, functional, and social status. Overall mortality in the Senning cohort did not differ from the Mustard group, but Senning patients had better functional status, greater participation in sports activities, and fewer baffle related problems.

Haemoptysis in a patient with tetralogy of Fallot: a combined surgical and interventional approach

Haemoptysis may occur in patients with tetralogy of Fallot and major aorto-pulmonary collateral arteries. We describe such a patient in whom bleeding from a major aorto-pulmonary collateral artery produced severe pulmonary haemorrhage. Interventional closure of the artery could not be performed because it perfused the native pulmonary arteries. Instead, we inserted a conduit between the right ventricle and the native pulmonary arteries, followed by percutaneous closure of the collateral artery. Our patient demonstrates the increasing necessity for combined surgical and interventional procedures.

Modified technique of stent fenestration of the atrial septum

OBJECTIVES

To develop a modified technique for stenting the atrial septum in the treatment of patients with a failing Fontan operation or pulmonary hypertension.

SETTING

Two tertiary referral centres.

STUDY DESIGN

Prospective collaborative clinical study.

PATIENTS AND METHODS

A stent was mounted on a standard valvoplasty balloon catheter which was constricted to a predefined diameter by a loop created from a temporary pacing wire. Full balloon inflation created a diabolo shaped stent configuration. The technique was employed in 12 consecutive patients to relieve symptoms of a failing Fontan circulation (n = 6) or severe pulmonary hypertension (n = 6).

RESULTS

Ex vivo studies confirmed that a diabolo shaped stent configuration could be achieved using the above technique. Transcatheter stent implantation was successful in all 12 patients. All six Fontan patients showed significant clinical improvement. Right atrial pressure decreased from (mean (SD)) 16.8 (2.5) to 13.7 (1.9) mm Hg (p < 0.05), and arterial oxygen saturation from 92.8 (1.8)% to 82.7 (3.8)% (p < 0.01). Six patients underwent successful stent fenestration for treatment of pulmonary hypertension. All stents were patent and stable at the most recent follow up (mean 1.75 (1.05) years). No early or late stent related complications were encountered.

CONCLUSIONS

This new technique allows placement of a diabolo shaped stent with a predefined diameter across the atrial septum. The diabolo shape increases stent stability, facilitates recrossing of the stent during future catheter interventions, and ensures medium term stent patency.