Heart rate in newborns is associated with age, sex and maternal levothyroxine therapy.

AIM: To evaluate the definition and causes of neonatal bradycardias. METHODS: This retrospective study included 135 term-born newborns referred for 24-hour Holter monitoring due to bradycardia. Bradycardia was defined as either a heart rate below 80 beats per minute (standard definition) or a heart rate below our recently published age-specific reference values for neonatal heart rate. RESULTS: The mean (SD) age was 6.1 (1.3) days. With standard definition, 107 newborns (79%) had bradycardia, whereas only 20 (15%) had a minimum heart rate lower than the age-specific reference. Younger newborns had lower heart rates. Each day increased the minimum, mean and maximum heart rate by 1.8 (95% CI: 1.0, 2.6), 4.2 (95% CI: 3.0, 5.3) and 2.1 beats per minute (95% CI: 0.3, 3.8), respectively. Male sex and maternal levothyroxine medication were negatively associated with the mean and maximum heart rate. None of the newborns had a cardiac cause for low heart rate. CONCLUSION: Among term newborns with bradycardias, younger age, male sex and maternal levothyroxine medication were associated with a lower heart rate on Holter monitoring. Given the age-related increase in heart rate, the 80 beats per minute limit as a universal threshold for abnormal heart rate in newborns appears inappropriate.

Recessive TMOD1 mutation causes childhood cardiomyopathy.

Familial cardiomyopathy in pediatric stages is a poorly understood presentation of heart disease in children that is attributed to pathogenic mutations. Through exome sequencing, we report a homozygous variant in tropomodulin 1 (TMOD1; c.565C>T, p.R189W) in three individuals from two unrelated families with childhood-onset dilated and restrictive cardiomyopathy. To decipher the mechanism of pathogenicity of the R189W mutation in TMOD1, we utilized a wide array of methods, including protein analyses, biochemistry and cultured cardiomyocytes. Structural modeling revealed potential defects in the local folding of TMOD1R189W and its affinity for actin. Cardiomyocytes expressing GFP-TMOD1R189W demonstrated longer thin filaments than GFP-TMOD1wt-expressing cells, resulting in compromised filament length regulation. Furthermore, TMOD1R189W showed weakened activity in capping actin filament pointed ends, providing direct evidence for the variant's effect on actin filament length regulation. Our data indicate that the p.R189W variant in TMOD1 has altered biochemical properties and reveals a unique mechanism for childhood-onset cardiomyopathy.

Younger postnatal age is associated with a lower heart rate on Holter monitoring during the first week of life.

To evaluate heart rate (HR), the presence of extrasystoles and other Holter findings among healthy newborns, and to collect data for new normal limits for Holter parameters in newborns. For this cross-sectional study, 70 healthy term newborns were recruited to undergo 24-h Holter monitoring. Linear regression analysis was used in HR analyses. The age-specific limits for HRs were calculated using linear regression analysis coefficients and residuals. The mean (SD) age of the infants was 6.4 (1.7) days during the recording. Each consecutive day of age raised the minimum and mean HR by 3.8 beats per minute (bpm) (95% CI: 2.4, 5.2; P < .001) and 4.0 bpm (95% CI: 2.8, 5.2; P < .001), respectively. Age did not correlate with maximum HR. The lowest calculated limit for minimum HR ranged from 56 bpm (aged 3 days) to 78 bpm (aged 9 days). A small number of atrial extrasystoles and ventricular extrasystoles were observed in 54 (77%) and 28 (40%) recordings, respectively. Short supraventricular or ventricular tachycardias were found in 6 newborns (9%). CONCLUSION:  The present study shows an increase of 20 bpm in both the minimum and mean HRs of healthy term newborns between the 3rd and 9th days of life. Daily reference values for HR could be adopted in the interpretation of HR monitoring results in newborns. A small number of extrasystoles are common in healthy newborns, and isolated short tachycardias may be normal in this age group. WHAT IS KNOWN: • The current definition of bradycardia in newborns is 80 beats per minute. • This definition does not fit into the modern clinical setting of continuously monitored newborns, where benign bradycardias are commonly observed. WHAT IS NEW: • A linear and clinically significant increase in heart rate was observed in infants between the ages of 3 and 9 days. • It appears as though lower normal limits for heart rate could be applied to the youngest newborns.

Multicenter cohort study on duration of antiarrhythmic medication for supraventricular tachycardia in infants.

Antiarrhythmic medication (AM) is commonly used to prevent supraventricular tachycardia (SVT) recurrence in infants. Our aim was to determine whether a shorter duration of AM is sufficient to prevent atrioventricular reentrant tachycardia (AVRT) recurrence and evaluate risk factors for recurrence of SVT after discontinued AM.This multicenter cohort study included all infants diagnosed with SVT in the five university hospitals in Finland between 2005 and 2017. Those diagnosed between 2005 and 2012 received AM for 12 months (group 1), and those diagnosed between 2013 and 2017 received AM for 6 months (group 2). A total of 278 infants presented with AVRT (group 1, n = 181; group 2, n = 97), and the median AM duration was 12.0 months (interquartile range [IQR] 11.4-13.4) and 7.0 months (IQR 6.0-10.2), respectively. Propranolol was the most frequently used first-line AM (92% and 95%). Recurrence-free survival rates were over 88% until 12 months after AM prophylaxis in both groups, without any statistically significant difference between them. Independent risk factors for recurrence of SVT after discontinuation of AM were need of combination AM (HR 2.2, 95% CI 1.14-4.20), Wolff-Parkinson-White (WPW) syndrome (HR 2.4, 95% CI 1.25-4.59), and age over 1 month at admission (HR 2.2, 95% CI 1.12-4.48).    Conclusion: Shortening AM duration in infants from 12 to 6 months does not seem to lead to more frequent SVT recurrence. The risk factors for recurrence of SVT were WPW syndrome, need of combination AM, and age over 1 month.

Extrasystoles or short bradycardias of the newborn seldom require subsequent 24-hour electrocardiographic monitoring.

AIM: To retrospectively assess the indications for and findings on 24-hour electrocardiographic (Holter) monitoring in newborns, focussing on bradycardias and extrasystoles. METHODS: Data included 337 term-born infants. Holter indications were categorised into bradycardias below 80 beats per minute, extrasystoles, any tachycardia and other. Heart rate below 60 beats per minute, pathological atrioventricular conduction, supraventricular or ventricular tachycardia, or either atrial premature contractions over 10% or ventricular premature contractions over 5% of total beats were defined as significant arrhythmia on Holter. RESULTS: The median age was 6 days (range: 2-62 days). Bradycardia (42%) or extrasystoles (32%) were the most common Holter indications. Fifty-three infants (16%) had significant arrhythmia on Holter. Heart disease or 12-lead electrocardiogram expressing extrasystoles or conduction abnormalities were associated with significant arrhythmias (p = 0.046 and p < 0.001, respectively). Twenty-seven of 109 infants (25%) with extrasystoles as a Holter indication had abnormal Holter results, but only seven (6.4%) had significant arrhythmia on Holter if the 12-lead electrocardiogram was normal. No pathology was found behind bradycardias below 80 beats per minute in the absence of heart disease. CONCLUSION: Among term newborns with extrasystoles or bradycardias, Holter monitoring could be targeted to infants with heart disease or abnormal electrocardiograms.

Cardiac Function After Cardiotoxic Treatments for Childhood Cancer-Left Ventricular Longitudinal Strain in Screening.

Background: The majority of childhood cancer survivors (CCSs) have been exposed to cardiotoxic treatments and often present with modifiable cardiovascular risk factors. Our aim was to evaluate the value of left ventricular (LV) longitudinal strain for increasing the sensitivity of cardiac dysfunction detection among CCSs. Methods: We combined two national cohorts: neuroblastoma and other childhood cancer survivors treated with anthracyclines. The final data consisted of 90 long-term CCSs exposed to anthracyclines and/or high-dose chemotherapy with autologous stem cell rescue and followed up for > 5 years and their controls (n = 86). LV longitudinal strain was assessed with speckle tracking (Qlab) and LV ejection fraction (EF) by three-dimensional echocardiography (3DE). Results: Of the CCSs, 11% (10/90) had abnormal LV longitudinal strain (i.e., < -17.5%); of those, 70% (7/10) had normal 3DE LV EF. Multivariable linear model analysis demonstrated that follow-up time (p = 0.027), sex (p = 0.020), and BMI (p = 0.002) were significantly associated with LV longitudinal strain. Conversely, cardiac risk group, hypertension, age, cumulative anthracycline dose or exposure to chest radiation were not. Conclusion: LV longitudinal strain is a more sensitive method than LV EF for the detection of cardiac dysfunction among CCSs. Therefore, LV longitudinal strain should be added to the screening panel, especially for those with modifiable cardiovascular risk factors.

3-Year Follow-Up of Radiation-Associated Changes in Diastolic Function by Speckle Tracking Echocardiography.

BACKGROUND: Radiation therapy (RT) results in myocardial changes consisting of diffuse fibrosis, which may result in changes in diastolic function. OBJECTIVES: The aim of this study was to explore RT-associated changes in left ventricular (LV) diastolic function. METHODS: Sixty chemotherapy-naive patients with left-sided, early-stage breast cancer were studied with speckle tracking echocardiography at 3 time points: prior to, immediately after, and 3 years after RT. Global and regional early diastolic strain rate (SRe) were quantified, as were parameters of systolic function. RESULTS: Regional changes in SRe, particularly the apical and anteroseptal segments, were observed over time and were more evident than global changes. The apical SRe declined from a median of 1.24 (interquartile range: 1.01 to 1.39) s-1 at baseline to 1.02 (interquartile range: 0.79 to 1.15) s-1 at 3 years of follow-up (p < 0.001). This decline was associated with the left ventricular maximal radiation dose (ß = 0.36, p = 0.007). The global SRe was <1.00 s-1 (SRedep) in 11 (18.3%) patients at baseline, 21 (35%) patients (p = 0.013) post-RT, and 17 (28.3%) patients (p = 0.051) at 3 years. SRedep post-RT was independently associated with baseline cardiac abnormalities (odds ratio: 0.26; 95% confidence interval: 0.08 to 0.84; p = 0.025); SRedep at 3 years of follow-up was associated with the baseline Charlson comorbidity index (odds ratio: 2.36; 95% confidence interval: 1.17 to 4.77; p = 0.017). Diastolic function abnormalities were evident even in patients with preserved global longitudinal strain at 3 years. CONCLUSIONS: RT resulted in changes in the SRe in the apical and anteroseptal segments over 3 years of follow-up. Changes in SRe apical segments were present even in patients with preserved systolic function and were independently associated with RT dose and cardiovascular comorbidities.

Velocity vector imaging shows normal cardiac systolic function in survivors of severe bronchopulmonary dysplasia at six to 16 years of age.

AIM: This study evaluated global myocardial function and associations between cardiac function and lung function in very low birth weight (VLBW) children, with and without severe radiographic bronchopulmonary dysplasia (BPD), at six to 14 years of age. METHODS: We studied 34 VLBW and 19 term-born controls, and the VLBW group was further divided into a BPD group with severe radiographic BPD and those without radiographic BPD in infancy. Detailed right and left ventricular myocardial functions were analysed by velocity vector imaging, and the left ventricular mass was calculated. The associations between cardiac function and lung function were assessed by impulse oscillometry. RESULTS: The right and left ventricular myocardial systolic functions and the left ventricular mass were similar in the three groups. Lung function was not associated with cardiac systolic function. Neonatal exposure to dexamethasone treatment was negatively associated with right ventricular function, as measured by the automated fractional area change, with an odds ratio of 7.9 and 95% confidence interval of 1.9-33.5 (p = 0.005). CONCLUSION: Lung function measurements were not associated with cardiac systolic function in preterm infants at six to 14 years of age. Neonatal exposure to dexamethasone, used for weaning from the ventilator, was negatively associated with right ventricular function.

Radiotherapy-induced global and regional differences in early-stage left-sided versus right-sided breast cancer patients: speckle tracking echocardiography study.

Radiotherapy (RT) to the thoracic region increases late cardiovascular morbidity and mortality. The impact of breast cancer laterality on cardiac function is largely unknown. The aim of this prospective study was to compare RT-induced changes in left-sided and right-sided breast cancer patients using speckle tracking echocardiography (STE). Sixty eligible patients with left-sided breast cancer and 20 with right-sided breast cancer without chemotherapy were evaluated prospectively before and early after RT. A comprehensive echocardiographic examination included three dimensional measurements and STE of the left ventricle (LV). The global longitudinal strain (GLS) was reduced from -18.3 ± 3.1 to -17.2 ± 3.3% (p = 0.003) after RT in patients with left-sided breast cancer. Similarly, regional analysis showed a reduction in the apical strain from -18.7 ± 5.3 to -16.7 ± 4.9% (p = 0.002) and an increase in basal values from -21.6 ± 5.0 to -23.3 ± 4.9% (p = 0.024). Patients with right-sided breast cancer showed deterioration in basal anterior strain segments from -26.3 ± 7.6 to -18.8 ± 8.9% (p < 0.001) and in pulsed tissue Doppler by 0.825 [0.365, 1.710] cm/s (p < 0.001). In multivariable analysis, the use of aromatase inhibitor (ß = -2.002, p = 0.001) and decreased LV diastolic volume (ß = -0.070, p = 0.025) were independently associated with the decrease in GLS. RT caused no changes in conventional LV systolic measurements. RT induced regional changes corresponded to the RT fields. Patients with left-sided breast cancer experienced apical impact and global decline, whereas patients with right-sided breast cancer showed basal changes. The regional differences in cardiac impact warrant different methods in screening and in the follow-up of patients with left-sided versus right-sided breast cancer.

Very low birthweight bronchopulmonary dysplasia survivors had similar cardiac outcomes to controls at six years to 14 years of age.

AIM: This study evaluated cardiac function and its associations with lung function and neonatal pulmonary morbidity in very low birthweight (VLBW) children, with and without severe radiographic bronchopulmonary dysplasia (radBPD), at school age. METHODS: We examined 18 VLBW children with radBPD, 17 VLBW children without radBPD and 18 healthy term-born children using conventional echocardiography, tissue Doppler imaging, speckle tracking echocardiography and real-time three-dimensional echocardiography at six years to 14 years of age. Lung function was studied by impulse oscillometry. Plasma N-terminal-proBNP concentrations were measured. RESULTS: Cardiac function and N-terminal-proBNP concentrations did not differ between the groups. No associations were found between cardiac function and neonatal dexamethasone, oxygen or ventilator therapies. In VLBW children, poorer reactance correlated with larger left ventricle (LV) end-systolic (Spearman's ρ = -0.45) and end-diastolic (ρ = -0.50) volumes and higher resistance correlated with higher LV dyssynchrony indexes, with ρ ranging from 0.37 to 0.48. Greater bronchodilation responses correlated with lower early diastolic myocardial relaxation velocities, with ρ ranging from 0.39 to 0.42. CONCLUSION: BPD survivors had normal cardiac function at the age of six years to 14 years. No associations were found between neonatal pulmonary morbidity and cardiac parameters. Poorer lung function correlated modestly with LV echocardiographic parameters in VLBW children.

Speckle tracking echocardiography detects decreased cardiac longitudinal function in anthracycline-exposed survivors of childhood cancer.

UNLABELLED: Longitudinal motion significantly contributes to the contraction of the ventricles. We studied the left (LV) and right ventricular (RV) longitudinal functions in 75 anthracycline-exposed, long-term childhood cancer survivors and 75 healthy controls with conventional echocardiography, tissue Doppler imaging (TDI), speckle tracking echocardiography (STE) of the mitral and tricuspid annular motion, and real-time three-dimensional echocardiography (RT-3DE). Cardiac magnetic resonance (CMR) imaging was performed on 61 of the survivors. The survivors had lower systolic myocardial velocities in the LV and lower diastolic velocities in both ventricles by TDI than did their healthy peers. The STE-based tissue motion annular displacement (TMAD) values describing the LV and RV systolic longitudinal function (MAD and TAD mid%, respectively) were also lower among the survivors (15.4 ± 2.4 vs. 16.1 ± 2.2 %, p = 0.049 and 22.5 ± 3.0 vs. 23.5 ± 3.0 %, p = 0.035). MAD and TAD mid in millimeters correlated with the respective ventricular volumes measured with RT-3DE or CMR. CONCLUSION: Childhood cancer survivors exposed to low to moderate anthracycline doses had decreased longitudinal systolic and diastolic functions (TDI or STE) compared with healthy controls. The STE-based TMAD is a fast and reproducible method to assess cardiac longitudinal function. What is Known? • High anthracycline doses cause LV dysfunction as evidenced by a decreased ejection fraction. What is new? • Low to moderate anthracycline doses also have a negative impact on the LV and RV longitudinal systolic and diastolic function. • TMAD is a new and fast method to assess the cardiac longitudinal function after anthracycline exposure.

Cardiac biomarkers indicate a need for sensitive cardiac imaging among long-term childhood cancer survivors exposed to anthracyclines.

AIM: The role that plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac troponins T (cTnT) and I (cTnI) play in supplementing imaging to screen for cardiac late effects remains controversial and the impact of high-sensitivity cTnT and troponin-specific autoantibodies (cTnAAbs) remains unexplored. We studied the role of cardiac biomarkers as indicators of the late effects of anthracyclines among childhood cancer survivors. METHODS: We measured NT-proBNP, cTnT, high-sensitivity cTnT, cTnI and cTnAAbs in 76 childhood cancer survivors at a median of 9 years after primary diagnosis. The survivors underwent conventional and real-time three-dimensional echocardiography and 62 underwent cardiac magnetic resonance imaging (MRI). RESULTS: Of the survivors, four (5.3%) without risk factors for cardiotoxicity were cTnAAb-positive with an impaired cardiac function in MRI. Another four (5.3%) had an abnormal NT-proBNP level associated with an abnormal cardiac function and risk factors for cardiotoxicity. None showed measurable cardiac troponins, determined by the three different methods, with even the high-sensitivity cTnT-levels remaining normal. CONCLUSION: Elevated plasma NT-proBNP or cTnAAbs indicated that childhood cancer survivors benefitted from being evaluated with modern imaging, despite normal function in conventional echocardiography. However, troponins did not seem to provide additional information on the late cardiotoxicity of anthracyclines.

Three-dimensional echocardiography and cardiac magnetic resonance imaging in the screening of long-term survivors of childhood cancer after cardiotoxic therapy.

The left ventricular (LV) volumes, ejection fraction (EF), and dyssynchrony indexes for the 16 and 12 cardiac segments (Tmsv16-SD and Tmsv12-SD, respectively) were analyzed among nonadult, anthracycline-exposed long-term survivors of childhood cancer and compared with those of healthy controls using conventional and real-time 3-dimensional echocardiography (RT-3DE) with cardiac magnetic resonance (CMR) imaging in a prospective, cross-sectional, single tertiary center setting. Seventy-one survivors and gender-, body surface area-, and age-matched healthy controls were studied by conventional echocardiography and RT-3DE. Fifty-eight of the 71 survivors underwent also CMR. The survivors were evaluated in 2 groups. Group I consisted of 63 exposed to anthracyclines and group II consisted of 8 also exposed to cardiac irradiation. By RT-3DE, the group I survivors had a lower LVEF (57% vs 60%, respectively, p = 0.003) and larger body surface area-indexed LV end-systolic volume (31 vs 28 ml/m(2), respectively, p = 0.001) than controls. The Tmsv16-SD was higher in group II than in I (1.93% vs 1.39%, respectively, p = 0.003). None of the survivors had an abnormal fractional shortening (<28%), but 10% had an LVEF <50% by RT-3DE. An LVEF <55% was detected in 45 of 58 (78%) of those imaged with CMR. In conclusion, RT-3DE seems to detect more abnormalities in cardiac function than conventional echocardiography following childhood cancer therapy. The LV dyssynchrony indexes derived from RT-3DE appear potentially useful in assessing the early signs of cardiotoxicity between anthracycline and cardiac irradiation exposed long-term survivors of childhood cancer.

Cardiac troponin I, cardiac troponin-specific autoantibodies and natriuretic peptides in children with hypoplastic left heart syndrome.

OBJECTIVES: To evaluate serum levels of cardiac troponin I (cTnI), autoantibodies against cardiac troponin (cTnAAbs) and natriuretic peptides during the treatment protocol in children with hypoplastic left heart syndrome (HLHS). METHODS: In a prospective study, we had 18 consecutive children with HLHS, for whom serum samples were analysed before the Norwood operation, before the bidirectional Glenn (BDG) operation, at the age of one year and before total cavo-pulmonary connection (TCPC). In addition, we performed a cross-sectional study in 22 children examined before TCPC. Controls comprised 34 healthy children. RESULTS: In the prospective study, troponin I was positive in eight children before the Norwood operation. At the next follow-up, six children were positive. Thereafter, in all samples, cTnI was negative. Serum levels of natriuretic peptides decreased during the treatment protocol but remained higher than in controls throughout the study. In the cross-sectional study, cTnI levels were negative, but levels of natriuretic peptides were higher than in controls. Levels of cTnI and natriuretic peptides showed no correlation with oxygen saturation or haemoglobin concentration. Autoantibodies against cardiac troponin appeared in one patient but not in the control children. CONCLUSIONS: Cardiac TnI release is common before Norwood and BDG operations; then during the treatment protocol for HLHS, cTnI release resolves and serum levels of natriuretic peptides decrease. This may reflect a reduction of volume overload of the right ventricle during the surgical programme.

Cardiac magnetic resonance imaging in the evaluation of the late effects of anthracyclines among long-term survivors of childhood cancer.

OBJECTIVES: This study sought to examine the left ventricular (LV) and right ventricular (RV) function and signs of focal fibrosis among long-term survivors of childhood cancer with the use of cardiac magnetic resonance (CMR) imaging. BACKGROUND: Increased myocardial fibrosis has been detected in the endomyocardial biopsies of survivors. CMR has established its role in the assessment of both cardiac function and structure, and focal fibrosis of the myocardium is detectable with late gadolinium enhancement (LGE). METHODS: Sixty-two anthracycline-exposed long-term survivors of childhood cancer were studied at a mean age of 14.6 years. The LV and RV ejection fractions (EFs) and volumes were measured, and LGE was assessed using CMR. RESULTS: An abnormal LV function (EF <45%) was detected in 18% (11 of 62) of the survivors, and an abnormal RV function was detected in 27% (17 of 62) of the survivors. Subnormal (45% ≤ EF <55%) LV function were demonstrated in 61% (38 of 62) and subnormal RV function in 53% (33 of 62) of the survivors, respectively. Both the LV and RV end-systolic and LV end-diastolic volumes were increased compared with reference values. None of the study patients showed LGE. CONCLUSIONS: A considerable proportion of the long-term survivors of childhood cancer with anthracycline exposure demonstrate signs of cardiac dysfunction detectable by CMR, with the RV also being involved. Yet, myocardial fibrosis does not seem to be detectable at a median of 7.8 years after anthracycline therapy.

Cardiac troponin I in congenital heart defects with pressure or volume overload.

OBJECTIVE: To evaluate the prevalence of cardiac troponin I (cTnI) and autoantibodies to cTn in children with congenital heart defects with volume or pressure overload fulfilling the criteria for treatment, and in healthy children. DESIGN: The study groups comprised 78 children with volume overload caused by an atrial septal defect or a patent ductus arteriosus, and 60 children with pressure overload caused by coarctation of the aorta or stenosis of the aortic or the pulmonary valve, and 74 healthy controls. Serum levels of natriuretic peptides, cTnI, and autoantibodies to cTn were analyzed at baseline, prior to treatment and in 64 patients 6 months after treatment. RESULTS: At baseline, one child with volume overload, 12 children with pressure overload, and one healthy control had positive cTnI. Further analysis of the pressure overload subgroup revealed that the children with positive cTnI were younger than those with negative cTnI, and had higher levels of natriuretic peptides. The pressure gradient at the coarctation site or stenotic valve was higher in those with positive TnI. Six months after treatment, 63 of 64 children examined were cTnI negative. CONCLUSIONS: The cTnI release is more frequently associated with pressure than volume overload which resolves after treatment in most children.

Bilateral absence of the superior vena cava.

Bilateral absence of the superior vena cava (SVC) is a very rarely detected, mainly asymptomatic congenital vascular anomaly. Though usually innocent, this anomaly may complicate cardiothoracic surgery and certain procedures like central venous catheter insertion. This SVC anomaly is poorly known, and we assume that its incidence in the general population may be higher than detected. In this paper, we summarize current knowledge on this anomaly and its clinical implications. In addition, we present a neonatal case with bilateral absence of the SVC associated with a fetal cystic hygroma. Conclusion. Totally absent SVC can cause unexpected problems during cardiothoracic surgery. Suspicion of SVC absence should arise in basic echocardiography. Our paper suggests that, like other congenital anomalies, bilateral absent SVC may be associated with a fetal cyctic hygroma.

Catecholaminergic polymorphic ventricular tachycardia.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmogenic disorder that causes syncopal episodes related with stress or emotion and even sudden cardiac deaths. Signs and symptoms usually begin in childhood. A suspicion of CPVT should be kept in mind when a child or an adolescent suddenly loses consciousness, particularly if this happens upon physical exercise or sudden mental stress. During the past decade, the knowledge of CPVT genetics and physiology has increased. Exercise testing is essential when suspecting arrhythmogenic origin of syncope, and in the case of CPVT, it may be even more sensitive than Holter monitoring. Beta-antiadrenergic medication can substantially decrease the mortality associated with CPVT. Asymptomatic patients with known CPVT gene defects should also be treated because sudden cardiac death may be the first manifestation of the disease. An implantable cardioverter-defibrillator may also be required in the most severe CPVT cases. In this review, we summarise the current knowledge on the clinical characteristics, diagnostic, genetic and prognostic features of CPVT in children. In all, 133 publications covering 60 years were checked, and those written in English and containing ten or more, mainly paediatric CPVT cases, were included. In addition, a CPVT family with three members and delayed diagnoses until late childhood and adulthood is presented.

Hemodynamic improvement is faster after percutaneous ASD closure than after surgery.

OBJECTIVES: Hemodynamic effects of surgical and percutaneous closure of atrial septal defect (ASD) were evaluated. BACKGROUND: ASD causes volume overload of right ventricle (RV) and is associated with distortion and dysfunction of left ventricle (LV). The amount and timing of hemodynamic changes after ASD closure are not well known. METHODS: The study group consisted of 7 children treated surgically and 17 treated in the catheterization laboratory. In the control group, there were 51 healthy children. RV size and LV end-diastolic and systolic dimensions, volumes, and function were examined by two- and three- dimensional echocardiography and serum concentrations of natriuretic peptides measured prior to ASD closure, and 1, 6, and 12 months thereafter. RESULTS: In all children with ASD, during the 1-year follow-up, the z score of RV end-diastolic diameter decreased from a median 5.00 SD to 2.25 SD (P < 0.001). Dilatation of RV did not resolve entirely during 1-year follow-up in either treatment group. End-diastolic LV diameter increased from -1.50 to -0.50 SD (P < 0.001). LV size increased slower in the surgical subgroup but reached control levels in both groups. Concentrations of natriuretic peptides increased during the first month after ASD closure and normalized thereafter in patients treated percutaneously but remained higher than in controls in patients treated surgically. CONCLUSIONS: During 1-year follow-up after ASD closure, RV size decreases but does not normalize in all patients. The size of the LV normalizes after ASD closure but the increase in LV size is slower in patients treated surgically. Serum levels of ANPN and proBNP are elevated prior to ASD closure but decrease thereafter to control levels in patients treated with the percutaneous technique but not in those treated surgically.

Diastolic dysfunction without left ventricular hypertrophy is an early finding in children with hypertrophic cardiomyopathy-causing mutations in the beta-myosin heavy chain, alpha-tropomyosin, and myosin-binding protein C genes.

OBJECTIVES: We investigated the presence of left ventricular hypertrophy (LVH) and features of diastolic dysfunction in genotype-confirmed children from families with hypertrophic cardiomyopathy (HCM) and healthy control children. BACKGROUND: In subjects with HCM-causing mutations, LVH usually does not evolve until adolescence. Diastolic dysfunction has not been systematically evaluated in children carrying HCM-causing mutations. METHODS: All children (aged 1.5-16.7 years) from 14 HCM families with identified disease-causing mutations (the Arg719Trp mutation in the beta-myosin heavy chain gene [MYH7], the Asp175Asn mutation in the alpha-tropomyosin gene [TPM1], the Gln1061X mutation in the myosin-binding protein C gene [MYBPC3], and the IVS5-2A-->C mutation in the MYBPC3 gene) and 53 matched control children were examined with electrocardiography and 2- and 3-dimensional echocardiography (2DE and 3DE). Natriuretic peptides were measured in children from HCM families and 67 control children. RESULTS: Of 53 children from HCM families, 27 (51%) had a disease-causing mutation (G+). G+ children had slightly thicker septum on 2DE compared with the control children (P = .004), but only 3 (11%) of 27 G+ children exceeded the 95th percentile values of the body surface area-adjusted maximal LV thickness of healthy children (the major echocardiographic criterion for HCM). However, prolonged isovolumetric relaxation time, increased left atrial volume on 3DE, or increased levels of NT-proANP, all features suggestive of diastolic dysfunction, were found in 14 (52%) of 27 G+ children. CONCLUSIONS: In children with HCM-causing mutations, signs of diastolic dysfunction are found in about half of the cases, as LVH is present only in small percentage of these children.