Nico Blom - Academia.edu (original) (raw)

Papers by Nico Blom

International Journal of Neonatal Screening, 2018

European Journal of Pediatrics, 2018

JACC: Clinical Electrophysiology, 2018

Heart rhythm, Jan 28, 2018

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an uncommon inherited arrhythmia ... more Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an uncommon inherited arrhythmia disorder characterized by adrenergically-evoked ventricular arrhythmias. Mutations in the cardiac calcium release channel/ryanodine receptor gene (RYR2) are identified in the majority of patients with CPVT. RyR2 is also the major RyR isoform expressed in the brain. To estimate the prevalence of intellectual disability (ID) and other neurodevelopmental disorders (NDDs) in RYR2-associated CPVT (CPVT1) and to study the characteristics of these patients. We reviewed the medical records of all CPVT1 patients from twelve international centers and analyzed the characteristics of all CPVT1 patients with concomitant NDDs. We functionally characterized the mutations to assess their response to caffeine activation. We did not correct for potential confounders. Among 421 CPVT1 patients, we identified 34 patients with ID (8%; 95% confidence interval, 6-11%). Median age at diagnosis was 9.3 years (int...

The Journal of pediatrics, 2018

To assess the accuracy of pulse oximetry screening for critical congenital heart defects (CCHDs) ... more To assess the accuracy of pulse oximetry screening for critical congenital heart defects (CCHDs) in a setting with home births and early discharge after hospital deliveries, by using an adapted protocol fitting the work patterns of community midwives. Pre- and postductal oxygen saturations (SpO) were measured ≥1 hour after birth and on day 2 or 3. Screenings were positive if the SpO measurement was <90% or if 2 independent measures of pre- and postductal SpO were <95% and/or the pre-/postductal difference was >3%. Positive screenings were referred for pediatric assessment. Primary outcomes were sensitivity, specificity, and false-positive rate of pulse oximetry screening for CCHD. Secondary outcome was detection of noncardiac illnesses. The prenatal detection rate of CCHDs was 73%. After we excluded these cases and symptomatic CCHDs presenting immediately after birth, 23 959 newborns were screened. Pulse oximetry screening sensitivity in the remaining cohort was 50.0% (95% ...

European heart journal, Jan 27, 2018

To clarify the clinical characteristics and outcomes of children with SCN5A-mediated disease and ... more To clarify the clinical characteristics and outcomes of children with SCN5A-mediated disease and to improve their risk stratification. A multicentre, international, retrospective cohort study was conducted in 25 tertiary hospitals in 13 countries between 1990 and 2015. All patients ≤16 years of age diagnosed with a genetically confirmed SCN5A mutation were included in the analysis. There was no restriction made based on their clinical diagnosis. A total of 442 children {55.7% boys, 40.3% probands, median age: 8.0 [interquartile range (IQR) 9.5] years} from 350 families were included; 67.9% were asymptomatic at diagnosis. Four main phenotypes were identified: isolated progressive cardiac conduction disorders (25.6%), overlap phenotype (15.6%), isolated long QT syndrome type 3 (10.6%), and isolated Brugada syndrome type 1 (1.8%); 44.3% had a negative electrocardiogram phenotype. During a median follow-up of 5.9 (IQR 5.9) years, 272 cardiac events (CEs) occurred in 139 (31.5%) patients...

European Journal of Pediatrics, 2017

Trends in Cardiovascular Medicine, 2017

Circulation. Arrhythmia and electrophysiology, 2017

In congenital long-QT syndrome, age, sex, and genotype have been associated with cardiac events, ... more In congenital long-QT syndrome, age, sex, and genotype have been associated with cardiac events, but their effect on the trend in QTc interval has never been established. We, therefore, aimed to assess the effect of age and sex on the QTc interval in children and adolescents with type 1 (LQT1) and type 2 (LQT2) long-QT syndrome. QTc intervals of 12-lead resting electrocardiograms were determined, and trends over time were analyzed using a linear mixed-effects model. The study included 278 patients with a median follow-up of 4 years (interquartile range, 1-9) and a median number of 6 (interquartile range, 2-10) electrocardiograms per patient. Both LQT1 and LQT2 male patients showed QTc interval shortening after the onset of puberty. In LQT2 male patients, this was preceded by a progressive QTc interval prolongation. In LQT1, after the age of 12 years, male patients had a significantly shorter QTc interval than female patients. In LQT2, during the first years of life and from 14 to 26...

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology, Jan 19, 2015

The Journal of Emergency Medicine, 2013

Foetal supraventricular tachycardia (SVT) with hydrops foetalis is associated with a high morbidi... more Foetal supraventricular tachycardia (SVT) with hydrops foetalis is associated with a high morbidity and mortality rate. If SVT with hydrops foetalis persists despite transplacental therapy, direct foetal treatment can be initiated. One foetus was found to have SVT with hydrops foetalis during the 29th week of pregnancy, and the condition persisted despite transplacental treatment. Amiodarone was administered directly via the umbilical vein, and the SVT resolved. A second foetus was found to have SVT with hydrops foetalis during the 28th week of pregnancy. The condition persisted despite maternal antiarrhythmic medication. Direct treatment of the foetus with amiodarone was successful. Amiodarone is the treatment of choice for direct foetal therapy for SVT, and can be administered safely via the umbilical vein. Direct foetal therapy should be considered for the treatment of foetal SVT with hydrops foetalis that occurs in the first 31 weeks of pregnancy and persists despite adequate tr...

Nederlands Tijdschrift voor Geneeskunde, 2005

OBJECTIVE: Analysis of long-term results with radiofrequency catheter ablation (RF ablation) in c... more OBJECTIVE: Analysis of long-term results with radiofrequency catheter ablation (RF ablation) in children. DESIGN: Retrospective. METHOD: Data were analysed from all 118 paediatric patients or = 10 years of age group in terms of final success rate (93% vs. 93%; p = 0.914) and complication rate (3% vs. 7%, p = 0.680). CONCLUSION: The long-term outcome of paediatric patients who underwent RF ablation was good. RF ablation in young children ( <10 years) was found to be safe and effective. These results demonstrate that it is also possible to curatively treat this group of patients with RF ablation in specialized centres

Pediatric Cardiology, 2019

A single 6-min walk test (6MWT) can be used to identify children with dilated cardiomyopathy (DCM... more A single 6-min walk test (6MWT) can be used to identify children with dilated cardiomyopathy (DCM) with a high risk of death or heart transplantation. To determine if repeated 6MWT has added value in addition to a single 6MWT in predicting death or heart transplantation in children with DCM. Prospective multicenter cohort study including ambulatory DCM patients ≥ 6 years. A 6MWT was performed 1 to 4 times per year. The distance walked was expressed as percentage of predicted (6MWD%). We compared the temporal evolution of 6MWD% in patients with and without the study endpoint (SE: all-cause death or heart transplantation), using a linear mixed effects model. In 57 patients, we obtained a median of 4 (IQR 2–6) 6MWTs per patient during a median of 3.0 years of observation (IQR 1.5–5.1). Fourteen patients reached a SE (3 deaths, 11 heart transplantations). At any time during follow-up, the average estimate of 6MWD% was significantly lower in patients with a SE compared to patients withou...

Cardiology in the Young, 2019

Aim: In patients after atrioventricular septal defect correction, altered geometry leads to a cha... more Aim: In patients after atrioventricular septal defect correction, altered geometry leads to a changed position and subsequent flow over the left ventricular outflow tract. We hypothesised that this altered flow may influence haemodynamics in the ascending aorta. Methods: In total, 30 patients after atrioventricular septal defect correction (age 27.6 ± 12.8 years) and 28 healthy volunteers (age 24.8 ± 13.7 years) underwent 4D flow cardiovascular magnetic resonance. Left ventricular ejection fraction and mean and peak wall shear stress calculated at ascending aortic peak systole were obtained from cardiovascular magnetic resonance. Left ventricular outflow tract data including velocity and diameter were obtained from echocardiography. Results: Patients showed a higher mean (911 ± 173 versus 703 ± 154 mPa, p = 0.001) and peak ascending aortic wall shear stress (1264 ± 302 versus 1009 ± 240 mPa, p = 0.001) compared to healthy volunteers. Increased blood flow velocities over the left ven...

International Journal of Cardiology, 2019