Catecholaminergic polymorphic ventricular tachycardia. An important diagnosis in children with syncope and normal heart

Syncope in children is primarily related to vagal hyperreactivity, but ventricular tachycardia (VT) way rarely be seen. Catecholaminergic polymorphic VT is a rare entity that can occur in children without heart disease and with a normal QT interval, which may cause syncope and sudden cardiac death. In this report, we describe the clinical features, treatment, and clinical follow-up of three children with syncope associated with physical effort or emotion and cathecolaminergic polymorphic VT. Symptoms were controlled with beta-blockers, but one patient died suddenly in the fourth year of follow-up. Despite the rare occurrence, catecholaminergic polymorphic VT is an important cause of syncope and sudden death in children with no identified heart disease and normal QT interval.

Unsupported valvuloplasty in children with congenital mitral valve anomalies. Late clinical results

OBJECTIVE: To analyze late clinical evolution after surgical treatment of children, with reparative and reconstructive techniques without annular support. METHODS: We evaluated 21 patients operated upon between 1975 and 1998. Age 4.67±3.44 years; 47.6% girls; mitral insufficiency 57.1% (12 cases), stenosis 28.6% (6 cases), and double lesion 14.3% (3 cases). The perfusion 43.10±9.50min, and ischemia time were 29.40±10.50min. The average clinical follow-up in mitral insufficiency was 41.52±53.61 months. In the stenosis group (4 patients) was 46.39±32.02 months, and in the double lesion group (3 patients), 39.41±37.5 months. The echocardiographic follow-up was in mitral insufficiency 37.17±39.51 months, stenosis 42.61±30.59 months, and in the double lesion 39.41±37.51 months. RESULTS: Operative mortality was 9.5% (2 cases). No late deaths occurred. In the group with mitral insufficiency, 10 (83.3%) patients were asymptomatic (p=0.04). The majorit y with mild reflux (p=0.002). In the follow-up of the stenosis group, all were in functional class I (NYHA); and the mean transvalve gradient varied between 8 and 12mmHg, average of 10.7mmHg. In the double lesion group, 1 patient was reoperated at 43 months. No endocarditis or thromboembolism were reported. CONCLUSION: Mitral stenosis repair has worse late results, related to the valve abnormalities and associated lesions. The correction of mitral insufficiency without annular support showed good long-term results.

Diagnostic value of the tilt-table test for the assessment of syncope in children and adolescents

OBJECTIVE - To assess the diagnostic value, the characteristics, and feasibility of tilt-table testing in children and adolescents. METHODS - From August 1991 to June 1997, we retrospectively assessed 94 patients under the age of 18 years who had a history of recurring syncope and presyncope of unknown origin and who were referred for tilt-table testing. These patients were divided into 2 groups: group I (children) - 36 patients with ages ranging from 3 to 12 (mean of 9.19±2.31) years; group II (adolescents) - 58 patients with ages ranging from 13 to 18 (mean of 16.05±1.40) years. We compared the positivity rate, the type of hemodynamic response, and the time period required for the test to become positive in the 2 groups. RESULTS - The positivity rates were 41.6 % and 50% for groups I and II, respectively. The pattern of positive hemodynamic response that predominated in both groups was the mixed response. The mean time period required for the test to become positive was shorter in group I (11.0±7.23 min) than in group II (18.44±7.83 min). No patient experienced technical difficulty or complications. CONCLUSION - No difference was observed in regard to feasibility, positivity rate, and pattern of positive response for the tilt-table test in children and adolescents. Pediatric patients had earlier positive responses.

Assessment of splanchnic perfusion with gastric tonometry in the immediate postoperative period of cardiac surgery in children

OBJECTIVE - A prospective, nonrandomized clinical study to assess splanchnic perfusion based on intramucosal pH in the postoperative period of cardiac surgery and to check the evolution of patients during hospitalization. METHODS - We studied 10 children, during the immediate postoperative period after elective cardiac surgery. Sequential intramucosal pH measurements were taken, without dobutamine (T0) and with 5mcg/kg/min (T1) and 10 (T2) mcg/kg/min. In the pediatric intensive care unit, intramucosal pH measurements were made on admission and 4, 8, 12, and 24 hours thereafter. RESULTS - The patients had an increase in intramucosal pH values with dobutamine 10mcg/kg/min [7.19± 0.09 (T0), 7.16±0.13(T1), and 7.32±0.16(T2)], (p=0.103). During the hospitalization period, the intramucosal pH values were the following: 7.20±0.13 (upon admission), 7.27±0.16 (after 4 hours), 7.26±0.07 (after 8 hours), 7.32±0.12 (after 12 hours), and 7.38±0.08 (after 24 hours), (p=0.045). No deaths occurred, and none of the patients developed multiple organ and systems dysfunction. CONCLUSION - An increase in and normalization of intramucosal pH was observed after dobutamine use. Measurement of intramucosal pH is a type of monitoring that is easy to perform and free of complications in children during the postoperative period of cardiac surgery.

Epidemiological study of congenital heart defects in children and adolescents: analysis of 4,538 cases

OBJECTIVE: To analyze the frequency and prevalence of congenital heart defects in a tertiary care center for children with heart diseases. METHODS: We carried out an epidemiological assessment of the first medical visit of 4,538 children in a pediatric hospital from January 1995 to December 1997. All patients with congenital heart defects had their diagnoses confirmed at least on echocardiography. The frequency and prevalence of the anomalies were computed according to the classification of sequential analysis. Age, weight, and sex were compared between the groups of healthy individuals and those with congenital heart defects after distribution according to the age group. RESULTS: Of all the children assessed, 2,017 (44.4%) were diagnosed with congenital heart disease, 201 (4.4%) with acquired heart disease, 52 (1.2%) with arrhythmias, and 2,268 (50%) were healthy children. Congenital heart diseases predominated in neonates and infants, corresponding to 71.5% of the cases. Weight and age were significantly lower in children with congenital heart defects. Ventricular septal defect was the most frequent acyanotic anomaly, and tetralogy of Fallot was the most frequent cyanotic anomaly. CONCLUSION: Children with congenital heart defects are mainly referred during the neonatal period and infancy with impairment in gaining weight. Ventricular septal defect is the most frequent heart defect.

Study of the cardiac alterations in HIV-infected children consequent to the antiretroviral therapy: prospective study of 47 cases

OBJECTIVE: Detect of cardiac alterations in children with AIDS and compare their evolution with the administration of only one anti-retroviral and the recent cases who received drugs in combination. METHODS: We prospectively studied 47 children in 3 groups: group 1, 20 cases treated only with zidovudine; group 2, 10 patients treated initially with zidovudine and later with a combination of drugs and in group 3, 17 patients, who receiced two or three since the beginning. In all patients it was done chest X-ray, EKG and echocardiography every 6 months and after death complete pathological study. RESULTS: Among the 45 patients cases 26 (57%) were index cases. Malnutrition, diarrhea tachycardia, signs of congestive heart failure, pericardial effusion, abnormal ventricular repolarization and arrhythmias were more frequent in group 1. Echocardiographic abnormalities were present in 10 (50%) children of group 1. They were less frequent in the others two groups. In regard to the outcome in group 1, two patients had worsening of sings of cardiomyopaty and 4 died. Cardiac dysfunction in all cases of group 2 and 3 improved with the medication. CONCLUSION:- The children who received combination and their cardiac alterations had more favorable outcome than those who received only one drug.

Initial diagnostic errors in children suspected of having heart disease: prevalence and long-term consequences

OBJECTIVE: To access the incidence of diagnostic errors in the initial evaluation of children with cardiac murmurs. METHODS: We evaluated our 7-years of experience in a public pediatric cardiology outpatient clinic. Of 3692 patients who were sent to the hospital, 2603 presented with a heart murmur and were investigated. Patients for whom a disagreement existed between the initial and final diagnoses were divided into the following 2 groups: G1 (n=17) with an initial diagnosis of an innocent murmur and a final diagnosis of cardiopathy, and G2 (n=161) with an initial diagnosis of cardiopathy and a final diagnosis of a normal heart. RESULTS: In G1, the great majority of patients had cardiac defects with mild hemodynamic repercussions, such as small ventricular septal defect and mild pulmonary stenosis. In G2, the great majority of structural defects were interventricular communication, atrial septal defect and pulmonary valve stenosis. CONCLUSION: A global analysis demonstrated that diagnostic error in the initial evaluation of children with cardiac murmurs is real, reaching approximately 6% of cases. The majority of these misdiagnoses were in patients with an initial diagnosis of cardiopathy, which was not confirmed through later complementary examinations. Clinical cardiovascular examination is an excellent resource in the evaluation of children suspected of having cardiopathy. Immediate outpatient discharge of children with an initial diagnosis of an innocent heart murmur seems to be a suitable approach.

Noninvasive cardiac assessment in children of women with systemic lupus erythematosus

OBJECTIVE: Noninvasive cardiac assessment of newborns and infants of women with systemic lupus erythematosus. The children had no congenital total atrioventricular block and were compared with the children of healthy women. METHODS: We prospectively assessed 13 newborns and infants aged 1 to 60 days, children of women with systemic lupus erythematosus and without congenital total atrioventricular block. These children were compared with 30 children of women who had no lupus or anti-Ro/SSA antibodies, and no risk factors for congenital heart disease either. Their age groups matched. The following examinations were performed: cardiological physical examination, electrocardiography, echocardiography, and signal-averaged electrocardiography. RESULTS: The statistical analysis showed no significant difference in ventricular function or in the cardiac conduction system between the groups. CONCLUSION: In regard to the conduction system and ventricular function in the absence of total atrioventricular block, no statistically significant difference was observed between the children of women with systemic lupus erythematosus and children of healthy women.

Electrophysiological Studies and Radiofrequency Ablations in Children and Adolescents with Arrhythmia

Background:Radiofrequency ablation is the standard non-pharmacological treatment for arrhythmias in pediatric patients. However, arrhythmias and their associated causes have particular features in this population.Objective:To analyze the epidemiological characteristics and findings of electrophysiological diagnostic studies and radiofrequency ablations in pediatric patients referred to the Electrophysiology Unit at Instituto de Cardiologia do Rio Grande do Sul, in order to characterize the particularities of this population.Methods:Cross-sectional study with 330 electrophysiological procedures performed in patients aged less than 20 years between June 1997 and August 2013.Results:In total, 330 procedures (9.6% of the overall procedures) were performed in patients aged less than 20 years (14.33 ± 3.25 years, age range 3 months to 19 years), 201 of which were males (60.9%). A total of 108 (32.7%) electrophysiological diagnostic studies were performed and of these, 48.1% showed abnormal findings. Overall, 219 radiofrequency ablations were performed (66.3%) with a success rate of 84.8%. The presence of an accessory pathway was the most prevalent finding, occurring in 158 cases (72.1%), followed by atrioventricular nodal reentrant tachycardia (16.8%), typical atrial flutter (3.1%) and extrasystoles originating from the right ventricular outflow tract (2.7%). Three patients developed complications during ablation (1.4%). Among congenital heart diseases, which occurred in 51 (15.4%) patients, atrial sept defect was the most frequent (27.4%), followed by ventricular sept defect (25.4%) and Ebstein's anomaly (17.6%).Conclusion:Electrophysiological study and radiofrequency ablation are effective tools for diagnosis and treatment of arrhythmias in the pediatric population.

Investigation of Copy Number Variation in Children with Conotruncal Heart Defects

Background:Congenital heart defects (CHD) are the most prevalent group of structural abnormalities at birth and one of the main causes of infant morbidity and mortality. Studies have shown a contribution of the copy number variation in the genesis of cardiac malformations.Objectives:Investigate gene copy number variation (CNV) in children with conotruncal heart defect.Methods:Multiplex ligation-dependent probe amplification (MLPA) was performed in 39 patients with conotruncal heart defect. Clinical and laboratory assessments were conducted in all patients. The parents of the probands who presented abnormal findings were also investigated.Results:Gene copy number variation was detected in 7/39 patients: 22q11.2 deletion, 22q11.2 duplication, 15q11.2 duplication, 20p12.2 duplication, 19p deletion, 15q and 8p23.2 duplication with 10p12.31 duplication. The clinical characteristics were consistent with those reported in the literature associated with the encountered microdeletion/microduplication. None of these changes was inherited from the parents.Conclusions:Our results demonstrate that the technique of MLPA is useful in the investigation of microdeletions and microduplications in conotruncal congenital heart defects. Early diagnosis of the copy number variation in patients with congenital heart defect assists in the prevention of morbidity and decreased mortality in these patients.

Insulin Resistance, Dyslipidemia and Cardiovascular Changes in a Group of Obese Children

Introduction: Obesity-related comorbidities are present in young obese children, providing a platform for early adult cardiovascular disorders. Objectives: To compare and correlate markers of adiposity to metabolic disturbances, vascular and cardiac morphology in a European pediatric obese cohort. Methods: We carried out an observational and transversal analysis in a cohort consisting of 121 obese children of both sexes, between the ages of 6 and 17 years. The control group consisted of 40 children with normal body mass index within the same age range. Markers of adiposity, plasma lipids and lipoproteins, homeostasis model assessment-insulin resistance, common carotid artery intima-media thickness and left ventricular diameters were analyzed. Results: There were statistically significant differences between the control and obese groups for the variables analyzed, all higher in the obese group, except for age, high-density lipoprotein cholesterol and adiponectin, higher in the control group. In the obese group, body mass index was directly correlated to left ventricular mass (r=0.542; p=0.001), the homeostasis model assessment-insulin resistance (r=0.378; p=<0.001) and mean common carotid artery intima-media thickness (r=0.378; p=<0.001). In that same group, insulin resistance was present in 38.1%, 12.5% had a combined dyslipidemic pattern, and eccentric hypertrophy was the most common left ventricular geometric pattern. Conclusions: These results suggest that these markers may be used in clinical practice to stratify cardiovascular risk, as well as to assess the impact of weight control programs.

Metabolic Syndrome and Importance of Associated Variables in Children and Adolescents in Guabiruba - SC, Brazil

Background:The risk factors that characterize metabolic syndrome (MetS) may be present in childhood and adolescence, increasing the risk of cardiovascular disease in adulthood.Objective:Evaluate the prevalence of MetS and the importance of its associated variables, including insulin resistance (IR), in children and adolescents in the city of Guabiruba-SC, Brazil.Methods:Cross-sectional study with 1011 students (6–14 years, 52.4% girls, 58.5% children). Blood samples were collected for measurement of biochemical parameters by routine laboratory methods. IR was estimated by the HOMA-IR index, and weight, height, waist circumference and blood pressure were determined. Multivariate logistic regression models were used to examine the associations between risk variables and MetS.Results:The prevalence of MetS, IR, overweight and obesity in the cohort were 14%, 8.5%, 21% and 13%, respectively. Among students with MetS, 27% had IR, 33% were overweight, 45.5% were obese and 22% were eutrophic. IR was more common in overweight (48%) and obese (41%) students when compared with eutrophic individuals (11%; p = 0.034). The variables with greatest influence on the development of MetS were obesity (OR = 32.7), overweight (OR = 6.1), IR (OR = 4.4; p ≤ 0.0001 for all) and age (OR = 1.15; p = 0.014).Conclusion:There was a high prevalence of MetS in children and adolescents evaluated in this study. Students who were obese, overweight or insulin resistant had higher chances of developing the syndrome.

Diastolic Function in Paced Children with Cardiac Defects: Septum vs Apex

AbstractIn children with structural congenital heart disease (CHD), the effects of chronic ventricular pacing on diastolic function are not well known. On the other hand, the beneficial effect of septal pacing over apical pacing is still controversial.The aim of this study was to evaluate the influence of different right ventricular (RV) pacing site on left ventricular (LV) diastolic function in children with cardiac defects.Twenty-nine pediatric patients with complete atrioventricular block (CAVB) and CHD undergoing permanent pacing were prospectively studied. Pacing sites were RV apex (n = 16) and RV septum (n = 13). Echocardiographic assessment was performed before pacemaker implantation and after it, during a mean follow‑up of 4.9 years.Compared to RV septum, transmitral E-wave was significantly affected in RV apical pacing (95.38 ± 9.19 vs 83 ± 18.75, p = 0.038). Likewise, parameters at the lateral annular tissue Doppler imaging (TDI) were significantly affected in children paced at the RV apex. The E´ wave correlated inversely with TDI lateral myocardial performance index (Tei index) (R2= 0.9849, p ≤ 0.001). RV apex pacing (Odds ratio, 0.648; confidence interval, 0.067-0.652; p = 0.003) and TDI lateral Tei index (Odds ratio, 31.21; confidence interval, 54.6-177.4; p = 0.025) predicted significantly decreased LV diastolic function.Of the two sites studied, RV septum prevents pacing-induced reduction of LV diastolic function.

Dyslipidemia is Associated with Unfit and Overweight-Obese Children and Adolescents

Abstract Background: Both poor aerobic fitness and obesity, separately, are associated with abnormal lipid profiles. Objective: To identify possible relationships of dyslipidemia with cardiorespiratory fitness and obesity, evaluated together, in children and adolescents. Methods: This cross-sectional study included 1,243 children and adolescents (563 males and 680 females) between 7 and 17 years of age from 19 schools. Obesity was assessed using body mass index (BMI) measurements, and cardiorespiratory fitness was determined via a 9-minute run/walk test. To analyze the lipid profile of each subject, the following markers were used: total cholesterol, cholesterol fractions (high-density lipoprotein and low-density lipoprotein) and triglycerides. Data were analyzed using SPSS v. 20.0, via prevalence ratio (PR), using the Poisson regression. Results: Dyslipidemia is more prevalent among unfit/overweight-obese children and adolescents compared with fit/underweight-normal weight boys (PR: 1.25; p = 0.007) and girls (PR: 1.30, p = 0.001). Conclusions: The prevalence of dyslipidemia is directly related to both obesity and lower levels of cardiorespiratory fitness.