Clinical Features and Natural History of Preadolescent Nonsyndromic Hypertrophic Cardiomyopathy

BACKGROUND

Up to one-half of childhood sarcomeric hypertrophic cardiomyopathy (HCM) presents before the age of 12 years, but this patient group has not been systematically characterized.

OBJECTIVES

The aim of this study was to describe the clinical presentation and natural history of patients presenting with nonsyndromic HCM before the age of 12 years.

METHODS

Data from the International Paediatric Hypertrophic Cardiomyopathy Consortium on 639 children diagnosed with HCM younger than 12 years were collected and compared with those from 568 children diagnosed between 12 and 16 years.

RESULTS

At baseline, 339 patients (53.6%) had family histories of HCM, 132 (20.9%) had heart failure symptoms, and 250 (39.2%) were prescribed cardiac medications. The median maximal left ventricular wall thickness z-score was 8.7 (IQR: 5.3-14.4), and 145 patients (27.2%) had left ventricular outflow tract obstruction. Over a median follow-up period of 5.6 years (IQR: 2.3-10.0 years), 42 patients (6.6%) died, 21 (3.3%) underwent cardiac transplantation, and 69 (10.8%) had life-threatening arrhythmic events. Compared with those presenting after 12 years, a higher proportion of younger patients underwent myectomy (10.5% vs 7.2%; P = 0.045), but fewer received primary prevention implantable cardioverter-defibrillators (18.9% vs 30.1%; P = 0.041). The incidence of mortality or life-threatening arrhythmic events did not differ, but events occurred at a younger age.

CONCLUSIONS

Early-onset childhood HCM is associated with a comparable symptom burden and cardiac phenotype as in patients presenting later in childhood. Long-term outcomes including mortality did not differ by age of presentation, but patients presenting at younger than 12 years experienced adverse events at younger ages.

Relationship Between Maximal Left Ventricular Wall Thickness and Sudden Cardiac Death in Childhood Onset Hypertrophic Cardiomyopathy

BACKGROUND

Maximal left ventricular wall thickness (MLVWT) is a risk factor for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). In adults, the severity of left ventricular hypertrophy has a nonlinear relationship with SCD, but it is not known whether the same complex relationship is seen in childhood. The aim of this study was to describe the relationship between left ventricular hypertrophy and SCD risk in a large international pediatric HCM cohort.

METHODS

The study cohort comprised 1075 children (mean age, 10.2 years [±4.4]) diagnosed with HCM (1-16 years) from the International Paediatric Hypertrophic Cardiomyopathy Consortium. Anonymized, noninvasive clinical data were collected from baseline evaluation and follow-up, and 5-year estimated SCD risk was calculated (HCM Risk-Kids).

RESULTS

MLVWT Z score was <10 in 598 (58.1%), ≥10 to <20 in 334 (31.1%), and ≥20 in 143 (13.3%). Higher MLVWT Z scores were associated with heart failure symptoms, unexplained syncope, left ventricular outflow tract obstruction, left atrial dilatation, and nonsustained ventricular tachycardia. One hundred twenty-two patients (71.3%) with MLVWT Z score ≥20 had coexisting risk factors for SCD. Over a median follow-up of 4.9 years (interquartile range, 2.3-9.3), 115 (10.7%) had an SCD event. Freedom from SCD event at 5 years for those with MLVWT Z scores <10, ≥10 to <20, and ≥20 was 95.6%, 87.4%, and 86.0, respectively. The estimated SCD risk at 5 years had a nonlinear, inverted U-shaped relationship with MLVWT Z score, peaking at Z score +23. The presence of coexisting risk factors had a summative effect on risk.

CONCLUSIONS

In children with HCM, an inverted U-shaped relationship exists between left ventricular hypertrophy and estimated SCD risk. The presence of additional risk factors has a summative effect on risk. While MLVWT is important for risk stratification, it should not be used either as a binary variable or in isolation to guide implantable cardioverter defibrillator implantation decisions in children with HCM.

Left and Right Ventricular Morphology, Function and Myocardial Deformation in Children with Left Ventricular Non-Compaction Cardiomyopathy: A Case-Control Cardiovascular Magnetic Resonance Study

Background: Left ventricular non-compaction (LVNC) is a rare cardiomyopathy typically involving the left ventricle (LV); however, the right ventricle (RV) can also be affected. This case-control study aimed to assess the morphology and function of LV and RV in children with LVNC. Methods: Sixteen children (13 ± 3 years, six girls) with LVNC were compared with 16 sex- and age-matched controls. LV and RV morphology and function were evaluated in cardiovascular magnetic resonance (CMR) studies. Additionally, LV and RV global radial (GRS), circumferential (GCS), and longitudinal strain (GLS) were assessed using tissue-tracking analysis. Results: Patients with LVNC did not differ from the healthy controls in terms of age, height, weight, and body surface area (BSA). In total, 4/16 subjects with LVNC had mid-wall late gadolinium enhancement (LGE). Compared to the control group, patients with LVNC had higher end-diastolic volume (EDV) indexed for body surface area (BSA), lower ejection fraction (EF), and lower LV strain parameters (all p < 0.05). Children with LVNC also presented with thicker RV apical trabeculation, whereas there were no differences in RV EF and EDV/BSA between the groups. Nevertheless, children with LVNC had impaired RV GRS and GCS (both p < 0.05). Conclusions: LVNC in pediatric patients is associated with LV enlargement and impaired LV systolic function. Additionally, children with LVNC have increased RV trabeculations and subclinical impairment of RV myocardial deformation.

Clinical presentation and long-term outcomes of infantile hypertrophic cardiomyopathy: a European multicentre study

AIMS

Children presenting with hypertrophic cardiomyopathy (HCM) in infancy are reported to have a poor prognosis, but this heterogeneous group has not been systematically characterized. This study aimed to describe the aetiology, phenotype, and outcomes of infantile HCM in a well-characterized multicentre European cohort.

METHODS AND RESULTS

Of 301 children diagnosed with infantile HCM between 1987 and 2019 presenting to 17 European centres [male n = 187 (62.1%)], underlying aetiology was non-syndromic (n = 138, 45.6%), RASopathy (n = 101, 33.6%), or inborn error of metabolism (IEM) (n = 49, 16.3%). The most common reasons for presentation were symptoms (n = 77, 29.3%), which were more prevalent in those with syndromic disease (n = 62, 61.4%, P < 0.001), and an isolated murmur (n = 75, 28.5%). One hundred and sixty-one (53.5%) had one or more co-morbidities. Genetic testing was performed in 163 (54.2%) patients, with a disease-causing variant identified in 115 (70.6%). Over median follow-up of 4.1 years, 50 (16.6%) underwent one or more surgical interventions; 15 (5.0%) had an arrhythmic event (6 in the first year of life); and 48 (15.9%) died, with an overall 5 year survival of 85%. Predictors of all-cause mortality were an underlying diagnosis of IEM [hazard ratio (HR) 4.4, P = 0.070], cardiac symptoms (HR 3.2, P = 0.005), and impaired left ventricular systolic function (HR 3.0, P = 0.028).

CONCLUSIONS

This large, multicentre study of infantile HCM describes a complex cohort of patients with a diverse phenotypic spectrum and clinical course. Although overall outcomes were poor, this was largely related to underlying aetiology emphasizing the importance of comprehensive aetiological investigations, including genetic testing, in infantile HCM.

Choroidal thickness changes in children with chronic heart failure due to dilated cardiomyopathy

PURPOSE

To evaluate choroidal thickness (CTh) in children with chronic heart failure (CHF) secondary to dilated cardiomyopathy (DCM) using spectral domain optical coherence tomography (SD-OCT) and to compare their values to those of healthy children.

METHODS

Sixty eyes of thirty children (mean age 9.9 ± 3.57 years) with chronic heart failure (left ventricular ejection fraction, LVEF ≤ 55%) due to DCM lasting for over 6 months were prospectively enrolled. The control group consisted of 30 age- (mean age 10.16 ± 3.42 years) and sex-matched healthy children. All participants underwent transthoracic echocardiography with LVEF measured using the Simpson method and had the blood serum level of N-terminal-pro-brain natriuretic peptide marker (NT-proBNP) determined. All children underwent SD-OCT and had subfoveal choroidal thickness (SFCTh) and CTh measured at 1500 µm (μm) nasally, temporally, superiorly and inferiorly from the fovea in both eyes by two investigators.

RESULTS

CTh at all locations was statistically significantly lower in children with DCM compared to the control group. Mean CTh in the group with CHF compared to the control group were (304.03 vs. 369.72 μm, p < 0.05) at the subfoveal location, (245.87 vs. 284 μm, p < 0.05) 1500 μm nasally from the fovea, (291.5 vs. 355.95 μm, p < 0.05) 1500 μm temporally from the fovea, (303.98 vs. 357.58 μm, p < 0.05) 1500 μm superiorly from the fovea and (290.92 vs. 344.96 μm, p < 0.05) 1500 μm inferiorly from the fovea. The average difference CTh between the study groups ranged from 38.13 to 65.69 μm at individual locations. In both groups, CTh was the thickest at subfoveal location (304.03 vs. 369.72 μm, p < 0.05) and the thinnest was 1500 μm nasally from the fovea (262.37 vs. 336.87 μm, p < 0.05). There was no correlation between CTh and age, gender, biometry and refractive error. No correlation was found between CTh and LVEF and NT-proBNP.

CONCLUSION

Patients with CHF due to DCM had a thinner CTh at all measured locations. The results of our research indicate that CHF affects CTh and this parameter may be very helpful in monitoring the clinical course of the disease in children with DCM.

The role of the electrocardiographic phenotype in risk stratification for sudden cardiac death in childhood hypertrophic cardiomyopathy

AIMS

The 12-lead electrocardiogram (ECG) is routinely performed in children with hypertrophic cardiomyopathy (HCM). An ECG risk score has been suggested as a useful tool for risk stratification, but this has not been independently validated. This aim of this study was to describe the ECG phenotype of childhood HCM in a large, international, multi-centre cohort and investigate its role in risk prediction for arrhythmic events.

METHODS AND RESULTS

Data from 356 childhood HCM patients with a mean age of 10.1 years (±4.5) were collected from a retrospective, multi-centre international cohort. Three hundred and forty-seven (97.5%) patients had ECG abnormalities at baseline, most commonly repolarization abnormalities (n = 277, 77.8%); left ventricular hypertrophy (n = 240, 67.7%); abnormal QRS axis (n = 126, 35.4%); or QT prolongation (n = 131, 36.8%). Over a median follow-up of 3.9 years (interquartile range 2.0-7.7), 25 (7%) had an arrhythmic event, with an overall annual event rate of 1.38 (95% CI 0.93-2.04). No ECG variables were associated with 5-year arrhythmic event on univariable or multivariable analysis. The ECG risk score threshold of >5 had modest discriminatory ability [C-index 0.60 (95% CI 0.484-0.715)], with corresponding negative and positive predictive values of 96.7% and 6.7.

CONCLUSION

In a large, international, multi-centre cohort of childhood HCM, ECG abnormalities were common and varied. No ECG characteristic, either in isolation or combined in the previously described ECG risk score, was associated with 5-year sudden cardiac death risk. This suggests that the role of baseline ECG phenotype in improving risk stratification in childhood HCM is limited.

Development of a Novel Risk Prediction Model for Sudden Cardiac Death in Childhood Hypertrophic Cardiomyopathy (HCM Risk-Kids)

Importance

Sudden cardiac death (SCD) is the most common mode of death in childhood hypertrophic cardiomyopathy (HCM), but there is no validated algorithm to identify those at highest risk.

Objective

To develop and validate an SCD risk prediction model that provides individualized risk estimates.

Design, Setting, and Participants

A prognostic model was developed from a retrospective, multicenter, longitudinal cohort study of 1024 consecutively evaluated patients aged 16 years or younger with HCM. The study was conducted from January 1, 1970, to December 31, 2017.

Exposures

The model was developed using preselected predictor variables (unexplained syncope, maximal left-ventricular wall thickness, left atrial diameter, left-ventricular outflow tract gradient, and nonsustained ventricular tachycardia) identified from the literature and internally validated using bootstrapping.

Main Outcomes and Measures

A composite outcome of SCD or an equivalent event (aborted cardiac arrest, appropriate implantable cardioverter defibrillator therapy, or sustained ventricular tachycardia associated with hemodynamic compromise).

Results

Of the 1024 patients included in the study, 699 were boys (68.3%); mean (interquartile range [IQR]) age was 11 (7-14) years. Over a median follow-up of 5.3 years (IQR, 2.6-8.3; total patient years, 5984), 89 patients (8.7%) died suddenly or had an equivalent event (annual event rate, 1.49; 95% CI, 1.15-1.92). The pediatric model was developed using preselected variables to predict the risk of SCD. The model's ability to predict risk at 5 years was validated; the C statistic was 0.69 (95% CI, 0.66-0.72), and the calibration slope was 0.98 (95% CI, 0.59-1.38). For every 10 implantable cardioverter defibrillators implanted in patients with 6% or more of a 5-year SCD risk, 1 patient may potentially be saved from SCD at 5 years.

Conclusions and Relevance

This new, validated risk stratification model for SCD in childhood HCM may provide individualized estimates of risk at 5 years using readily obtained clinical risk factors. External validation studies are required to demonstrate the accuracy of this model's predictions in diverse patient populations.

Biatrial performance in children with hypertrophic cardiomyopathy: CMR study

OBJECTIVES

To investigate biatrial mechanics and their relation with left ventricular outflow tract (LVOT) obstruction (LVOTO), the degree of hypertrophy, indices of ventricular diastolic function and fibrosis in children with hypertrophic cardiomyopathy (HCM).

METHODS

Fifty-five consecutive, prospectively recruited children with HCM (mean age 12.5 ± 4.6 years, 69.1% male), 19 (34.5%) of whom had LVOTO, underwent cardiac magnetic resonance and echocardiography with quantification of phasic components of biatrial function, biventricular diastolic function and fibrosis. Twenty healthy, sex-matched subjects served as controls.

RESULTS

We found a significant increase of left atrial (LA) and right atrial (RA) volumes and reduction in the majority of indices of contractile function, strains and strain rates (p < 0.05) in children with HCM compared with controls. Nearly all of the LA dynamics markers attained a significant association with the LVOT gradient (p < 0.05), the RA volumes and contractile functions were affected by LV fibrosis and mass (p < 0.05), and the RA mechanical components were related to the degree of LVOTO (p < 0.05). The minority of biatrial dynamics markers were associated with indices of ventricular diastolic function.

CONCLUSIONS

The majority of biatrial volumetric and functional indices were severely compromised in children with HCM compared with controls. The degree of LVOTO appears to trigger LA volumetric and LA and RA mechanical malfunction. On the other hand, the deterioration of RA volumetric components was linked to LV fibrosis and mass.

KEY POINTS

• Biatrial function was severely compromised in children with HCM. • Left atrial malfunction was associated with the degree of LVOTO. • Fibrosis and LV mass were related to RA volumetric and contractile dysfunction. • The degree of LVOTO was linked to right atrial mechanical abnormalities.

Left-ventricular mechanics in children with hypertrophic cardiomyopathy. CMR study

OBJECTIVES

To assess the magnitude of myocardial displacement abnormalities and their alterations with the fibrosis, left-ventricular (LV) outflow tract obstruction (LVOTO) and hypertrophy in juveniles with hypertrophic cardiomyopathy (HCM).

STUDY DESIGN

Fifty-five children [age 12,5±4.6years, 38 (69,1%) males, 19 (34,5%) with LVOTO] with HCM and 20 controls underwent cardiovascular magnetic resonance. The LV feature tracking (FT) derived strain and strain rates were quantified. Results of FT analysis were compared between HCM subjects and controls and between children with and without LVOTO.

RESULTS

Children with HCM exhibited decreased strain in both hypertrophied and nonhypertrophied segments versus controls. LV global longitudinal strain (LVGLS) rate (-0.69±0.04 vs -0.91±0.05, p=0,04), LV circumferential strain (LVCR) rate (-0.98±0.09 vs -1.27±0.06, p=0,02), LV radial strain (LVR) (18,5±1.9 vs 27,4±1.4, p<0,01) and LVR rate (0,98±0.1 vs 1,53±0.08, p<0,01) were substantially compromised in subjects with LVOTO vs without. In multivariable regression all LV myocardial dynamics markers, except for LVCR, exhibited a significant association with the degree of LVOTO. LVCR rate (β=0,31, p=0,02) and LVR (β=-0.24, p=0,04) were related to LV mass and only LVCR rate (β=0,15, p=0,03) was associated with the amount of LV fibrosis.

CONCLUSIONS

The reduction of all indices of LV myocardial mechanics in juvenile HCM patients was global but particularly pronounced in hypertrophied segments of the LV. The majority of the LV strains and strain rates were substantially compromised in subjects with LVOTO compared to patients without the obstruction. Myocardial mechanics indices seemed to be related to the degree of LVOTO rather than either to mass or the amount of fibrosis.

Comparison of echocardiography with tissue Doppler imaging and magnetic resonance imaging with delayed enhancement in the assessment of children with hypertrophic cardiomyopathy

INTRODUCTION

In children with hypertrophic cardiomyopathy (HCM) there often occurs a non-ischemic pattern of myocardial fibrosis, which could be the cause of impaired left ventricular (LV) diastolic function assessed by tissue Doppler imaging (TDI). The aim of the study was to determine the prevalence of myocardial fibrosis in children with HCM, and to evaluate its relationship with echocardiographic parameters including LV diastolic dysfunction.

MATERIAL AND METHODS

Sixty-three children with HCM, mean age 12.2 ±4.5 years, underwent magnetic resonance imaging (MRI) and echocardiographic study from January 2010 to April 2014. The results of MRI, echocardiography, and TDI velocities were analyzed and compared between children with and without myocardial fibrosis. Moreover, correlations between the results of echocardiography and MRI were assessed.

RESULTS

Our results showed a significant correlation between magnetic resonance and echocardiographic measurements of septal wall thickness, posterior wall thickness, LV mass and left atrial dimension. Children with myocardial fibrosis (60%) had a significantly thicker interventricular septum (21.3 vs. 1.8 mm; p < 0.0001) and larger left atrial dimension (36.7 vs. 27.8 mm; p = 0.0004) and volume index (42.0 vs. 26.6 ml/m²; p = 0.0011). Tissue Doppler imaging demonstrated significantly decreased lateral E' (9.02 vs. 13.53 cm/s; p < 0.0001) and septal E' (7.05 vs. 9.36 cm/s; p = 0.0082) velocities and a significantly increased transmitral lateral (10.34 vs. 6.68; p = 0.0091) and septal (13.1 vs. 9.8; p = 0.046) E/E' ratio in children with myocardial fibrosis.

CONCLUSIONS

Myocardial fibrosis in children with hypertrophic cardiomyopathy was associated with markers for disease severity such as larger septum thickness, enlargement of the left atrium as well as impairment of left ventricular diastolic function. Tissue Doppler imaging is a helpful tool to detect the presence of left ventricular diastolic dysfunction in children with hypertrophic cardiomyopathy and myocardial fibrosis.

Prognosis in children with pulmonary arterial hypertension: 10-year single-centre experience

BACKGROUND

Pulmonary arterial hypertension (PAH) is a rare progressive disease of the pulmonary arterioles with an unfavourable prognosis.

AIM

To evaluate survival and prognostic factors in patients with PAH diagnosed and treated at a single centre in the years 2004–2013.

METHODS

The study included 55 children (33 girls; 66%, 22 boys; 33%), with an average age 6.2 ± 6.0 years, with idiopathic PAH — n = 23 (42%), PAH associated with systemic-to-pulmonary shunts — n = 17 (31%), and PAH after corrective cardiac surgery — n = 15 (27%). Forty-seven of them (87%) were treated with advanced therapy.

RESULTS

During the follow-up with an average time of 5.6 ± 4.7 years 15 (27.3%) children died. The one-, three-, five-, and ten-year survival was, respectively, 83.1%, 77.1%, 70.7%, and 65.2%. The analysis of the survival curves revealed a better prognosis in patients with baseline N-terminal pro-B-type natriuretic peptide (NT-proBNP) level < 605 pg/mL (p = 0.024) and a higher probability of survival of three and five years in children at baseline I/II World Health Organisation functional class (WHO-FC). The higher risk of death was associated with a higher pressure in the right atrium (HR 1.23, p < 0.01) and higher pulmonary resistance (HR 1.1, p < 0.01), whereas no history of syncope had a better prognosis (HR 0.31, p = 0.03).

CONCLUSIONS

Survival in the study group was comparable to the currently published register data. Mortality risk factors were connected with the severity of the disease at diagnosis.

Predictors of Long-Term Outcome in Children with Hypertrophic Cardiomyopathy

To date limited data are available to predict the progression to end-stage heart failure (HF) with subsequent death (non-SCD), need for heart transplantation, or sudden cardiac death (SCD) in children with hypertrophic cardiomyopathy (HCM). We aimed to determine predictors of long-term outcome in children with HCM. A total of 112 children (median 14.1, IQR 7.8-16.6 years) were followed up for the median of 6.5 years for the development of morbidity and mortality, including arrhythmic and HF-related secondary end points. HF end point included HF-related death or heart transplant, and arrhythmic end point included resuscitated cardiac arrest, appropriate ICD discharge, or SCD. Overall, 23 (21 %) patients reached the pre-defined composite primary end point. At 10-year follow-up, the event-free survival rate was 76 %. Thirteen patients (12 %) reached the secondary arrhythmic end point, and 10 patients (9 %) reached the secondary HF end point. In multivariate model, prior cardiac arrest (r = 0.658), QTc dispersion (r = 0.262), and NSVT (r = 0.217) were independent predictors of the arrhythmic secondary end point, while HF (r = 0.440), LV posterior wall thickness (r = 0.258), LA size (r = 0.389), and decreased early transmitral flow velocity (r = 0.202) were all independent predictors of the secondary HF end point. There are differences in the risk factors for SCD and for HF-related death in childhood HCM. Only prior cardiac arrest, QTc dispersion, and NSVT predicted arrhythmic outcome in patients aged <18 years. LA size, LV posterior wall thickness, and decreased early transmitral flow velocity were strong independent predictors of HF-related events.

The usefulness of cardiovascular magnetic resonance imaging in children with myocardial diseases

BACKGROUND

Cardiovascular magnetic resonance (CMR) imaging is a clinically proven and reliable diagnostic method for the assessment of morphology, function, and characteristics of myocardial tissue in patients with myocardial diseases. The use of gadolinium contrast agents has created new diagnostic possibilities for tissue characterisation in patients with suspected or known cardiomyopathy, myocarditis, and cardiac tumours.

AIM

To evaluate the usefulness of CMR in the diagnostic process in children with myocardial diseases and to compare the results of CMR and other non-invasive cardiovascular methods, including echocardiography.

METHODS

The study included 112 children, with an average age of 12 ± 4.64 years, with various forms of myocardial disease: 63 children with hypertrophic cardiomyopathy (HCM), 9 with suspected myocarditis, 5 with history of myocarditis, 4 with dilated cardiomyopathy (DCM), 9 with suspected arrhythmogenic right ventricular cardiomyopathy (ARVC), 6 with left ventricular non-compaction cardiomyopathy (LVNC), 9 with suspected restrictive cardiomyopathy (RCM) to be differentiated with constrictive pericarditis (CP), and 7 with cardiac tumours.

RESULTS

CMR confirmed the echocardiographic diagnosis of HCM in 92% of children and ruled it out in 8%, and in three children apical hypertrophy was found. CMR revealed the presence of myocardial fibrosis in 60% of patients with HCM. In 33% of children with clinically suspected myocarditis CMR confirmed this diagnosis, while in 44% of them DCM was recognised. Of the five children with a history of myocarditis, in one patient CMR performed 13 years after myocarditis revealed features of post-inflammatory DCM. In 75% of patients with the echocardiographic diagnosis of post-inflammatory DCM the result of CMR was consistent. CMR ruled out the presence of ARVC in 89% of children. Echocardiographic and CMR diagnosis of LVNC was consistent in 67% of children. CMR confirmed the clinical diagnosis of RCM in 63% of patients, and in one patient CP was recognised. CMR confirmed the presence of cardiac tumour in 57% of children and excluded it in 43% of patients.

CONCLUSIONS

CMR is increasingly recognised as an important tool in the investigation of myocardial disease and should be part of routine clinical work-up. CMR provides an additional diagnostic technique to assess the presence or exclusion of an active myocarditis. In children with clinical and echocardiographic suspicion of LVNC, ARVC, RCM, CP, and cardiac tumours CMR can conclusively confirm the presence of the disease.

Assessment of the role of copy-number variants in 150 patients with congenital heart defects

BACKGROUND

Congenital heart defects are the most common group of major birth anomalies and one of the leading causes of infant deaths. Mendelian and chromosomal syndromes account for about 20% of congenital heart defects and in some cases are associated with other malformations, intellectual disability, and/or dysmorphic features. The remarkable conservation of genetic pathways regulating heart development in animals suggests that genetic factors can be responsible for a significantly higher percentage of cases.

THE AIM

Assessment of the role of CNVs in the etiology of congenital heart defects using microarray studies.

MATERIAL AND METHODS

Genome-wide array comparative genomic hybridization, targeting genes known to play an important role in heart development or responsible for abnormal cardiac phenotype was used in the study on 150 patients. In addition, we have used multiplex ligation-dependent probe amplification specific for chromosome 22q11.2 region.

RESULTS

We have identified 21 copy-number variants, including 13 known causative recurrent rearrangements (12 deletions 22q11.2 and one deletion 7q11.23), three potentially pathogenic duplications (5q14.2, 15q13.3, and 22q11.2), and five variants likely benign for cardiac anomalies. We suggest that abnormal copy-number of the ARRDC3 and KLF13 genes can be responsible for heart defects.

CONCLUSIONS

Our study demonstrates that array comparative genomic hybridization enables detection of clinically significant chromosomal imbalances in patients with congenital heart defects.

The usefulness of scintigraphy with (99m)Tc-anti-granulocyte antibody for diagnosis and follow-up in children with myocarditis

BACKGROUND AND AIM

The aim of this study was to investigate whether scintigraphy with (99m)Tc-Anti-Granulocyte antibody is useful for diagnosis and follow-up in children with myocarditis, and to determine its correlation with endomyocardial biopsy (EMB) and clinical features.

METHODS

A total of 11 children, mean age 13 years and presenting with symptoms of myocarditis, were evaluated at the time of initial presentation and 6, 12 and 24 months after the first study. In all patients, myocardial scintigraphy was performed with estimation of antigranulocyte antibody uptake. EMB was done in 10 patients at the time of initial presentation and in 8 patients after 6 months.

RESULTS

In 10 (91%) patients, positive antigranulocyte uptake was observed, with EMB confirming myocarditis in 8 children. In scintigraphy after 6 months, positive uptake was found in 9 (82%) patients, with EMB performed in 8 patients showing persistent myocarditis; after 12 months, scintigraphy indicated positive uptake in 7 (64%), and after 24 months only in 4 (36%) patients.

CONCLUSIONS

1. In 80% of patients with positive scintigraphy results, biopsy-proven myocarditis was observed. 2. The positive antigranulocyte uptake correlated with clinical features at diagnosis and in follow-up. 3. The control scintigraphy performed in follow-up after 6, 12, and 24 months allowed the evaluation of resolved or persistent myocarditis. 4. Myocardial scintigraphy results indicate that the inflammatory process in the myocardium decreases significantly after 12 months from the onset of the disease. 5. Scintigraphy with (99m)Tc-Anti-Granulocyte antibody seems to be a useful diagnostic method in myocarditis, but further studies are needed to establish its sensitivity and specificity.

[Symptoms, diagnosis and characteristic abnormalities in the coronary arteries in Kawasaki disease in children]

INTRODUCTION

Kawasaki disease (KD) is a vasculitis of unknown etiology, the diagnosis is based upon symptoms, characteristic abnormalities in the coronary arteries are the most important complications.

AIM

Establishment of a data base of the patients with KD, assignation of symptoms, and frequency of abnormalities in the coronary arteries according to the clinical manifestations and time of the diagnosis.

MATERIALS AND METHODS

The patients'data from selected centres of paediatric cardiology were put into a questionnaire form in the Internet. The data of 120 children were placed into data base in the year 2007, of which we analyzed 112 cases.

RESULTS

The most frequent symptoms were fever and abnormalities of oral mucosa. Complete KD was diagnosed in 73%, incomplete in 27% (median of age 28 and 19 months respectively). The disease was diagnosed before its 10th day in 60% with similar frequency of both clinical manifestations, abnormalities in the coronary arteries were observed in 59% with complete and in 44% with incomplete KD clinical sings. The disease lasting longer than 70 days was diagnosed in 40% with similar frequency in both groups of clinical manifestations, abnormalities in the coronary arteries were in 79% with complete and in 75% with incomplete KD. In all cases, abnormalities in coronary arteries were in 67% with complete and in 57% with incomplete KD.

CONCLUSIONS

The most frequent symptoms of Kawasaki disease are fever and abnormalities in the oral mucosa. Incomplete KD is more frequent in younger children. Despite complete KD in 40% of cases diagnosis was delayed. Abnormalities in the coronary arteries were more frequent in patients in whom KD was diagnosed only after the 10th day of the illness, but with the same frequency in both clinical manifestations. Diagnosis of incomplete KD before the 10th day of the illness was associated with lower risk of incidence of abnormalities in the coronary arteries.

[Kawasaki disease in children--9 years experience]

PURPOSE

The aim of the study was assessment of the course and treatment of Kawasaki disease on the basis of own experience.

MATERIAL AND METHODS

Between November 1995 and December 2004 Kawasaki disease (KD) was diagnosed in 30 patients, (20 boys, 10 girls). The median age in acute stage was 20 months (range 1-96 months). Patients were divided into 4 groups (gr) according to changes in coronary arteries (CA). Group 1 (N=13) without CA aneurysms (CAA), group II (N=5) with small (<5mm) CAA. Group III (N=5) with medium (5-8mm) CAA, group IV (N=7) with giant (>8mm) CAA. Echocardiographic examination was performed in all patients. In echocardiographic examination the following were observed: CAA and valvar insufficiency in 15 patients, left ventricle enlargement in 3 patients, pericardial effusion in 6 patients. The treatment was intravenous immunoglobulin and aspirin in all patients, steroid treatment in 2 patients methylprednisolone, in 2 patients prednisone, in l patient hydrocortisone. The anti-inflammatory treatment was started after 10 days of illness in 66.7% of patients. Thrombi in CAA were treated in 6 patients, the treatment was: in all tissue - type plasminogen activator iv and intracoronary in 2 patients; heparin in all; enoxaparine in 3 patients; abciximab in 2 patients; acenocumarol and aspirin in all. Coronary angiographies were performed in 2 patients in acute stage of disease for thrombolytic therapy and in 4 patients during follow-up. Myocardial perfusion was assessed in SPECT (Single Photon Emission Computed Tomography) in 6 patients. Two children with giant CAA died during the first 8 months of acute stage (6.7%), 2 patients we lost from follow-up. 26 patients are in follow-up.

RESULTS

during anti-inflammatory treatment (immunoglobulin, aspirin, steroid treatment) loss of fever, normalization of inflammatory markers, and no side effect, were observed except for 1 patient treated with methylprednosolone with thrombi in CAA during treatment and no side effects during treatment. During the follow-up period CAA regressed in 5 patients (35.7%), CAA became smaller in 7 patients (50%), CAA were the same in 2 patients (14.3%). Changes in echocardiographic examination: valvar insufficiency, left ventricle enlargement, pericardial effusion, disappeared during follow-up. Perfusion defects were observed in 4 patients in SPECT. In coronary angiography changes were observed in coronary arteries in 4 patients.

CONCLUSIONS

1. Kawasaki disease was diagnosed in 66.7% children after 10 days of illness. 2. Coronary artery aneurysms were found in 56.6% treated children. 3. Regression of CAA was observed in 37.5% patients mainly with small CAA. They became smaller in 50% cases mainly with medium and giant CAA. 4. Mortality rate was 6.7% and concerned children with giant CAA; they died during the first 8 months of illness. 5. Thrombolytic treatment of thrombi in CAA (rt-PA, heparin, enoxaparine, abciximab, acenocumarol, aspirin) was safe and successful. 6. In all patients with medium and giant CAA in the acute stage, changes were observed in echocardiographic, angiographic examination and myocardial perfusion during follow-up.