[B-type natriuretic peptide as a marker of cardiac dysfunction in children with chronic kidney disease]. / Peptyd natriuretyczny typu B jako marker uszkodzenia serca u dzieci z przewlekla choroba nerek.

Left ventricular hypertrophy is the most common organ damage in children with chronic kidney disease (CKD). AIM: The aim of the study was to assess the usefulness of B-type natriuretic peptide (BNP) as a marker of heart injury in children with CKD. MATERIALS AND METHODS: We included 66 children (41 boys and 25 girls) aged 0.7 to 18.6 (median 11.6) years with CKD stage 1-5. The concentrations of urea, creatinine, cystatin C and BNP in blood serum were assessed, and the estimated glomerular filtration rate (eGFR) was calculated from the Schwartz and Filler formulas. Patients were divided into groups depending on the CKD stage [group 1: CKD stages 1 + 2 (GFR> 60 ml/min/1.73 m2), group 2: stage 3 (GFR = 30-59 ml/min/1.73 m2), group 3: CKD stage 4 (GFR 15-29 ml/min/ 1.73 m2), group 4 - stage 5 (dialyzed children)]. On the basis of echocardiography, the left ventricular mass (LVM) was calculated, which was indexed for height (left ventricular mass index, LVMI). Left ventricular hypertrophy (LVH) was diagnosed if the LVMI value was > 95th percentile for sex and age. RESULTS: Depending on the CKD stage the median BNP concentrations for group 1, group 2, group 3, and group 4 were 2.5 pg/ml, 6.0 pg/ml, 9.3 pg/ml and 18.0 pg/ml, and the LVH prevalence 27.3%, 33.3%, 60.0% and 63.6% , respectively. Significant correlations between BNP concentration and LVH expressed by LVMI (R=0.256, p=0.038), creatinine (R=0.453, p<0.001), cystatin (R=0.494, p<0.001) and eGFR (R=-0.473, p<0.001) were found. CONCLUSIONS: In children with chronic kidney disease, BNP is an indicator of heart failure correlating with renal function parameters and left ventricular mass index.

Efficacy and safety of oral sildenafil in children with Down syndrome and pulmonary hypertension.

BACKGROUND: Despite the increased risk for pulmonary hypertension in children with Down syndrome, the response to treatment with targeted therapies for pulmonary hypertension in these patients is not well characterized. The Sildenafil in Treatment-naive children, Aged 1-17 years, with pulmonary arterial hypertension (STARTS-1) trial was a dose-ranging study of the short-term efficacy and safety of oral sildenafil in children with pulmonary arterial hypertension. We assessed the safety and efficacy of oral sildenafil in children with Down syndrome and pulmonary arterial hypertension. METHODS: This was a post-hoc analysis of children with Down syndrome and pulmonary arterial hypertension enrolled in the STARTS-1 trial. Mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance index (PVRI), and cardiac index (CI) were assessed at baseline and following 16 weeks of treatment with sildenafil. RESULTS: Of 234 patients randomized and treated in the STARTS-1 trial, 48 (20.5%) had Down syndrome. Although sildenafil produced dose-related reductions in PVRI and mPAP, compared with placebo, in non-Down syndrome patients and children developmentally able to exercise, this was not satisfactorily marked in patients with Down syndrome. The dose-related reductions in PVRI, compared with placebo, occurred in all subgroups, with the exception of the Down syndrome subgroup. Sildenafil appeared to be well tolerated in the Down syndrome subpopulation and the most frequently reported AEs were similar to those reported for the entire STARTS-1 population. CONCLUSION: Sildenafil treatment for 16 weeks had no effect on PVRI or mPAP in children with Down syndrome and pulmonary arterial hypertension. The results suggest that children with Down syndrome may be less responsive to sildenafil for pulmonary arterial hypertension, but the incomplete work-up for the etiology of pulmonary arterial hypertension may have introduced a potential bias. TRIAL REGISTRATION: Study received, September 8, 2005 (retrospectively registered); Study start, August 2003; ClinicalTrials.gov identifier, NCT00159913 .

Intermittent preexcitation indicates "a low-risk" accessory pathway: Time for a paradigm shift?

We report three patients with intermittent loss of the preexcitation pattern in the ECG that had undergone an electrophysiological study. Despite apparently poorly conducting accessory pathway (AP), in each case a fast anterograde conduction, either during spontaneous atrial fibrillation or during incremental atrial pacing (on isoproterenol) was documented; shortest preexcited RR intervals of 200-240 ms were observed. We review the literature and conclude that intermittent preexcitation observed on resting 12-lead ECG lacks sufficient specificity for the diagnosis of an AP with long refractory period and cannot be considered a substitute for electrophysiological study in patients with this electrocardiographical phenomenon.

Atypical cardiac myxoma in the course of Carney complex in the child. Case Report.

Cardiac tumors in infants and children are rare. Myxomas are the second (after rhabdomyomas) most common primary cardiac tumors in pediatric patients. Cardiac, cutaneous and mucous myxomas are likewise the second most frequent manifestation of the Carney complex, an autosomal dominant multi neoplasia syndrome, which consists of myxomas in different locations, spotty skin pigmentation and endocrine overactivity. We present a case of 13-years-old boy send to our department from a district hospital because of the large tumor in the right atrium discovered in the echo study. On admission he presented discrete signs of Cushing's syndrome and scarse pigmented nevi on the face and trunc. The detailed echo examination showed the large right atrial tumor with features of myxoma, protruding across the tricuspid valve into the right ventricle during diastolic period. Atypical location of cardiac myxoma as well as the signs of Cushing's syndrome suggested Carney's complex. Detailed endocrine studies confirmed the hypothesis. Thus two-step bilateral adrenalectomy was planned. The histopathologic study confirmed primary pigmented nodular adrenocortical disease.

A randomized, double-blind, placebo-controlled, dose-ranging study of oral sildenafil citrate in treatment-naive children with pulmonary arterial hypertension.

BACKGROUND: Safe, effective therapy is needed for pediatric pulmonary arterial hypertension. METHODS AND RESULTS: Children (n=235; weight ≥8 kg) were randomized to low-, medium-, or high-dose sildenafil or placebo orally 3 times daily for 16 weeks in the Sildenafil in Treatment-Naive Children, Aged 1-17 Years, With Pulmonary Arterial Hypertension (STARTS-1) study. The primary comparison was percent change from baseline in peak oxygen consumption (PV(O(2))) for the 3 sildenafil doses combined versus placebo. Exercise testing was performed in 115 children able to exercise reliably; the study was powered for this population. Secondary end points (assessed in all patients) included hemodynamics and functional class. The estimated mean±SE percent change in PV(O(2)) for the 3 doses combined versus placebo was 7.7±4.0% (95% confidence interval, -0.2% to 15.6%; P=0.056). PV(O(2)), functional class, and hemodynamics improved with medium and high doses versus placebo; low-dose sildenafil was ineffective. Most adverse events were mild to moderate in severity. STARTS-1 completers could enter the STARTS-2 extension study; patients who received sildenafil in STARTS-1 continued the same dose, whereas placebo-treated patients were randomized to low-, medium-, or high-dose sildenafil. In STARTS-2 (ongoing), increased mortality was observed with higher doses. CONCLUSIONS: Sixteen-week sildenafil monotherapy is well tolerated in pediatric pulmonary arterial hypertension. Percent change in PV(O(2)) for the 3 sildenafil doses combined was only marginally significant; however, PV(O(2)), functional class, and hemodynamic improvements with medium and high doses suggest efficacy with these doses. Combined with STARTS-2 data, the overall profile favors the medium dose. Further investigation is warranted to determine optimal dosing based on age and weight. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT00159913.

Coronary artery abnormalities in Kawasaki disease.

INTRODUCTION: Kawasaki disease is the number one cause of acquired heart disease among children in developed countries. AIM: The aim of the study was a retrospective analysis of the factors that may influence the persistence of coronary artery abnormalities in patients with Kawasaki disease. MATERIALS AND METHODS: Analyzing the medical records of patients hospitalized in the University Children's Hospital of Krakow in the years 2005-2011 we collected the data of 28 patients diagnosed with Kawasaki disease. The group was divided into two subgroups, depending on the duration of the persistence of changes in the coronary arteries - A (n = 17) for up to 6 months, B (n = 11) - for more than 6 months. Both groups were analyzed for the presence of factors that may influence the course of the disease. RESULTS: There were more boys in group A (11 boys (65%), 6 girls (35%)), whereas in group B the distribution was more uniform (6 boys (55%), 5 girls (45%)). The age of onset in group A was 37.9 months (SD 30.8), in group B 39.5 months (SD 16.7). 17.6% of patients in group A and 36.4% in group B were treated with glucocorticoids. CONCLUSIONS: In the group of patients in which coronary artery abnormalities disappeared more quickly, male and slightly older children dominated. The only difference observed between the 2 groups related to the frequency of the use of glucocorticoids, they were used more often in children, in whom coronary artery abnormalities persisted longer.

Metabolic syndrome as risk factor for left ventricular hypertrophy in children with chronic kidney disease.

Background: The metabolic syndrome (MS), a cluster of clinical and biochemical abnormalities including insulin resistance, dyslipidemia and hypertension, is often diagnosed in chronic kidney disease (CKD) children. Left ventricular hypertrophy (LVH) is a major target organ damage in hypertension and an important cardiovascular risk factor in CKD patients. We aimed to identify the most significant risk factors of LVH in children with CKD. Methods: Children with CKD stage 1-5 were enrolled in the study. MS was diagnosed according to De Ferranti (DF) as ≥3 from 5 criteria. Ambulatory blood pressure measurements (ABPM) and echocardiographic evaluation were performed. LVH was defined as ≥95th percentile of LV mass index related to height and age. Clinical and laboratory parameters included: serum albumin, Ca, HCT, cystatin C, creatinine, estimated glomerular filtration rate (eGFR) based on Schwartz formula, triglycerides, high-density lipoprotein (HDL), proteinuria, BMI standard deviation score (SDS), height SDS, waist circumference, ABPM data. Results: 71 children (28 girls/43 boys) with median age 14.05 (25%-75%:10.03-16.30) years and median eGFR 66.75 (32.76-92.32) ml/min/1.73m2 were evaluated. CKD stage 5 was diagnosed in 11 pts (15.5%). MS (DF) was diagnosed in 20 pts (28.2%). Glucose ≥ 110 mg/dL was present in 3 pts (4.2%); waist circumference ≥75th pc in 16 pts (22.5%); triglycerides ≥ 100 mg/dL in 35 pts (49.3%); HDL < 50mg/dL in 31 pts (43.7%) and BP ≥ 90th pc in 29 pts (40.8%), respectively. LVH was detected in 21 (29.6%) children. In univariate regression the strongest risk factor for LVH was CKD stage 5 (OR 4.9, p=0.0019) and low height SDS (OR 0.43,p=0.0009). In stepwise multiple logistic regression analysis (logit model) of the most important risk factors for LVH in CKD children, only three were statistically significant predictors: 1)MS diagnosis based on DF criteria (OR=24.11; 95%CI 1.1-528.7; p=0.043; Chi2 = 8.38,p=0.0038); 2), high mean arterial pressure (MAP SDS) in ABPM (OR=2.812; 95%CI 1.057-7.48; p=0.038;Chi2 = 5.91, p=0.015) and 3) low height SDS (OR=0.078; 95%CI 0.013-0.486;p=0.006; Chi2 = 25.01, p<0.001). Conclusions: In children with chronic kidney disease LVH is associated with the cluster of multiple factors, among them the components of MS, hypertension, stage 5 CKD and growth deficit were the most significant.

Recent achievements in transcatheter closure of ventricular septal defects: a systematic review of literature and a meta-analysis.

BACKGROUND: Ventricular septal defect (VSD) is one of the most common congenital heart defects. Currently, surgery remains the treatment of choice. However, transcatheter techniques for closing of various types of VSDs have become an alternative. AIMS: The objective of our study was to present the outcomes of transcatheter closure of various types of VSD based on a systematic review of recent publications. METHODS: A systematic review of studies published in English between January 2014 and March 2020 was performed using the PubMed database (MEDLINE) independently by 2 reviewers. Data on success and complication rates were extracted. Studies including fewer than 5 patients and those with acquired VSD were excluded from the analysis. RESULTS: Finally, 44 studies were included for analysis, with a total number of 4050 patients. The pooled estimate of the overall success rate based on the random effects model was 97.96% (95% CI, 97.37-98.56; Q test P 0.99; I 2 = 0%) for permanent VSD. CONCLUSIONS: Transcatheter closure of selected VSDs appears to be an effective and safe method of treatment. Recent studies have shown high rates of successful interventions with a low incidence of complications.

Left ventricular diastolic dysfunction in adolescents with type 1 diabetes reflects the long- but not short-term metabolic control.

OBJECTIVE: The aim of this study was to compare the LV morphology and function in adolescents with DM1 and their healthy peers. SUBJECTS AND METHODS: In 59 DM1 patients (30 girls, 29 boys,aged 14-17 years), and in control group (15 girls, 15 boys) LV was assessed by M-mode, 2D and Doppler echocardiography. The metabolic control was assessed in the long- (mean HbAlc value for the entire treatment period-HbA1c1), medium- (mean HbA1c for the past two pre-study years-HbA1c2), and short-term (HbA1c on the day of the study-HbA1c3). RESULTS: Diabetic patients presented an increase of IRT (0.062 vs. 0.056 s, p < 0.05 in boys, and 0.062 vs. 0.056 s, p < 0.05 in girls), A wave (56.1 vs. 53.95 cm/s in boys, and 60.3 vs. 58 cm/s in girls), and deceleration time values (0.16 vs. 0.15 s in boys, and 0.17 vs. 0.15 s in girls), decrease of E wave (97.35 vs. 104.9 cm/s in boys, and 99.67 vs. 101.8 cm/s in girls), as well as the E/A ratio (1.79 vs. 2.0 in boys, and 1.7 vs. 1.78 in girls). The systolic function was normal. In girls there was a correlation between IRT and HbA1c1 and HbA1c2 (r = 0.42, r = 0.46, p < 0.05); between the A wave and HbA1c2 (r = 0.46, p < 0.05); between LV posterior wall systolic dimension and HbA1c1, HbA1c2 (r = 0.45, r = 0.41, p < 0.05), and in boys between the A wave and HbA1c1 and HbA1c2 (r = 0.48, p < 0.01; r = 0.37, p < 0.05). CONCLUSIONS: Pubertal patients with DM1 demonstrate discrete impairment of the diastolic function beside normal systolic function of the LV. Further investigations are needed to assess the value of this observation. It seems that LV diastolic dysfunction in girls depends on the degree of insulin resistance and DM1 duration, and similarly as in boys, on the long-term metabolic control.

Echocardiography and Newer Imaging Techniques in Diagnosis and Long-Term Follow-Up of Primary Heart Tumors in Children.

BACKGROUND: Primary heart tumors (PHTs) in the pediatric population are very rare and do not manifest any characteristic symptoms. METHODS: A retrospective analysis of 61 cases was undertaken. Data from three centers for the years 2003-2018 were gathered. The tumors' clinical course, location, number, hemodynamic, treatment, and follow-up were evaluated. Echocardiography was complemented with magnetic resonance imaging, computer tomography, and histopathological examination. RESULTS: Out of 61 PHT diagnoses, 56 (91.8%) were circumstantial including all 16 (26.2%) prenatal tumors. The reasons for cardiological consultations were arrhythmia, syncopes, lowered physical performance, and murmurs. Only five patients (8.2%) were suspected of tumors based on previous symptoms of sclerosis tuberosa. Rhabdomyoma was the most frequently found PHT (60.7%). The tumors were predominantly located in the ventricles (49.1%) and intraventricular septum (14.9%) and tended to be single (70.5%). About 37.7% of patients suffered from coexistent multi-organ problems, two (3.28%) from congenital heart defects and one (1.64%) from Carney's syndrome. Tumor resection was performed on 26 (42.7%) patients, of which 16 (61.5%) underwent total and 10 (38.5%) partial tumor resection. During the follow-up (mean 4.3 years), 54 patients (88.5%) have improved or were stable, while seven (11.5%) died. CONCLUSIONS: Primary pediatric heart tumors are diagnosed completely circumstantially, and the most common is rhabdomyoma, although arrhythmia may suggest fibroma. Diagnosis of a heart tumor in children is not synonymous with fatal prognosis, and most of them require only constant observation. Life-saving operation allows improvement, while the prognosis for malignant tumors in children is definitely unfavorable.

Percutaneous balloon valvuloplasty for the treatment of pulmonary valve stenosis in children - a single centre experience.

BACKGROUND: Isolated pulmonary valve stenosis (PVS) is a common heart defect (6-9%); the preferred treatment is balloon pulmonary valvuloplasty (BPV). AIM: To assess BPV results in children with isolated PVS treated between 1988 and 2004, with a mean follow-up of 6.1 +/- 3.4 years. METHODS: The studied group consisted of 137 children (76 males and 61 females), aged 5.4 +/- 4.8 years. The diagnosis was based on physical examination, ECG, chest radiograph, echo, haemodynamic and angiocardiographic studies. The patients were divided into three groups, depending on the ratio of right ventricular systolic (RVSP) to systemic pressure (SP): I (n = 58) - RVSP < or = 75% of SP, II (n = 41) - RVSP = 76-100% of SP, III (n = 38) - RVSP > 100% of SP. In 7.3% of patients, dysplastic pulmonary valve (DPV) was seen. The balloon diameter to pulmonary valve annulus ratio was 1.29 +/- 0.1, and 1.42 +/- 0.1 in DPV children. RESULTS: Immediately post-BPV, the patients showed significantly (p < 0.001) decreased pressure gradient across PVS (I: 49.3 +/- 11.1 - 12.5 +/- 7.6, II: 75.6 +/- 12.3 - 17.0 +/- 13.0, III: 117.3 +/- 28 - 17.9 +/- 15.5 mmHg), decreased RVSP (I: 65.3 +/- 10.3 - 28.6 +/- 7.6, II: 91.7 +/- 11.6 - 35.0 +/- 14, III: 133.0 +/- 27.3 - 38.4 +/- 19.2 mmHg) and end-diastolic RV pressure (I: 6.2 +/- 3.0 - 5.6 +/- 7.6, II: 6.3 +/- 3.0 - 5.5 +/- 2.9, III: 8.5 +/- 3.0 - 7.2 +/- 2.3 mmHg), non-significant (p > 0.05) increase in pulmonary artery pressure in group I (15.8 +/- 1.1 - 16.8 +/- 0.9 mmHg) and II (15.8 +/- 1.2 - 17.8 +/- 1.3 mmHg) and a significant (p < 0.003) rise in group III (14.5 +/- 1.3 - 19.4 +/- 2.1 mmHg). The procedure was ineffective only in one (2.4%) child in group II, who required surgery. Complications were seen in five (3.6%) patients, including one case of a balloon being lodged in the iliac vein (surgical repair). Follow-up echo showed similar to immediate post BPV values of pressure gradients across PVS. Pre-BPV subpulmonary stenosis was seen in 5.1%, post-BPV - 15.3%, and end of follow-up - only 3.6% of children, mainly from group III. Pre-BPV tricuspid insufficiency > IIo was noted in 8.8%, significantly more frequently in group III; while in late follow-up, it was seen in 7.2%, e.g. twice as often in group III vs. groups I and II. Pulmonary regurgitation > IIo increased from 2.2% before BPV to 25.5%, i.e. 17.2%, 24.4% and 39.5%, respectively in groups I-III. Restenosis was observed in eight (5.8%) patients (group I - 1, III - 7), of whom five had re-BPV, two were operated on and one was disqualified due to insignificant restenosis. CONCLUSIONS: These long-term follow-up data confirm efficacy and safety of BPV performed in children with isolated PVS.

[Focal atrial tachycardia originating in the right atrial appendage]. / Czestoskurcz ogniskowy z uszka prawego przedsionka.

We present a case of 14-year-old boy with incessant atrial tachycardia from right atrial appendage, resistant to pharmacotherapy and with early signs of the left ventricle tachyarrhythmic dysfunction. The P-wave was positive in leads I, II, III, aVF, negative in aVR, aVL. Moreover, P waves configuration specific for this localization: negative in V1-V2 that become positive in V3-V6 was present. After first ablation session a recurrence was observed after 3 weeks, due to inadequate power delivery resulting from trabeculation/anatomy that limited conventional ablation catheter cooling. Second ablation session with the use of an active electrode cooling and 3D mapping system was successful.

Amiodarone-induced thyroid dysfunction in the developmental period: prenatally, in childhood, and adolescence - case reports and a review of the literature.

INTRODUCTION: Amiodarone is an important antiarrhythmic drug used in paediatric practice, mainly in children with complex congenital cardiac diseases and/or severe arrhythmias. One of the side effects of amiodarone therapy is thyroid dysfunction, which is observed in about 20% of patients. The thyroid dysfunction may present with various forms: from subclinical changes in hormone levels to amiodaroneinduced thyrotoxicosis (AIT) and amiodarone-induced hypothyroidism (AIH). MATERIAL AND METHODS: We reported six patients in the age range from two weeks to 14 years, with complex congenital cardiac diseases and severe arrhythmias, who developed amiodarone-induced thyroid dysfunctions: thyrotoxicosis or hypothyroidism or both together. The clinical signs and symptoms of all thyroid dysfunctions were atypical, most patients presented with an aggravation of heart insufficiency. Our patients with thyrotoxicosis were treated with combined therapy including thionamides and corticosteroids due to the presentation of mixed-identified type of AIT. RESULTS: Currently, five patients (one patient's status is unknown) are in biochemical and clinical euthyreosis; however, in one of them it was impossible to discharge amiodarone treatment. Three of them are still treated with levothyroxine, and two do not need thyroid treatment. CONCLUSIONS: Amiodarone-induced thyroid dysfunction is usually atypical; therefore, monitoring of thyroid status before, during, and after amiodarone is demanded. AIH could significantly influence the development of the child, while AIT could significantly deteriorate the clinical status of children with complex cardiac diseases. Early and proper diagnose of AIT and AIH allows the introduction of immediate and appropriate treatment considering the cardiac condition of the young patient.

[The assessment of heart function in children with chronic kidney disease (CKD)]. / Ocena funkcji serca u dzieci z przewlekla choroba nerek (PChN).

THE AIM OF THE STUDY: The echocardiography evaluation of cardiac function in children with CKD. PATIENTS AND METHODS: 30 children (17 males, 13 females), aged 2-20 yrs with CKD 2-5. Left ventricular (LV) dimensions, LV ejection fraction (EF) and LV mass index (LVMI), as well mitral inflow velocity (E/A waves) and isovolumetric relaxation time (IRT) were evaluated. RESULTS: Impaired diastolic heart function were ascertained in 12 patients (in 2 from 5 with CKD 3, in 3 from 10 with 4 and 7 from 14 with 5). Left ventricular hypertrophy was observed in 13 children with CDD 3-5 (4, 4, 5), and decreased ejection fraction in 2. CONCLUSIONS: The vast majority of children with chronic kidney disease demonstrate an impairment of diastolic cardiac function.

[24-hour pulse pressure in children with chronic kidney disease]. / Calodobowe cisnienie tetna u dziecl z przewlekla choroba nerek.

The aim of the study was to assess 24-h pulse pressure (PP) and to determine relationships between PP and echocardiographic parameters of left ventricle in children with chronic kidney disease (CKD). The study population included 47 children (mean age: 13.11 yrs) with CKD treated conservatively (n=14), with hemodialysis (HD) (n=13) and automated peritoneal dialysis (APD) (n=20). Retrospectively, antropometrical data, office blood pressure, ambulatory blood pressure monitoring (ABPM) variables and LV parameters in echocardiogaphy were analyzed. In study subjects, hypertension (HTN) was present in 25 (53.19%) and in 29 (61.7%) when based on office blood pressure and ABPM respectively. The prevalence of HTN was the highest in predialysis patients. 21 (44.6%) of children had left ventricular hypertrophy (LVH), which was the most frequently found in HD group. The mean PP value was 45.26 +/- 7.56 mmHg and was similar in all groups. Positive correlations were found between PP and weight (p < 0.001), height (p < 0.05), body surface area (p < 0.01) and LV measures (LV mass, LV posterior wall thickness and diastolic diameter of LV, all p < 0.05). Children with PP above median had tendency for greater LV mass (p = 0.06). There was no difference in severity of blood pressure and PP in children with/without LVH. However, in 45% of patients LVH was noted in whom the value of PP was greater than calculated normative value of PP (95 centile). HTN and LVH is common in children with CKD. A mean PP in children with CKD is lower when compared to adult population with CKD. The results confirm that PP increases with the age and an increasing PP has an influence on the changes of LV geometry. Assessment of PP in ABPM might help in identifying those with abnormal LV geometry.

[Syncope in children and adolescents]. / Omdlenia u dzieci i mlodocianych.

The report presents a definition and causes of syncope in children. Syncope differs from other states with loss of consciousness by causes leading to decreased perfusion and resultant transient cerebral dysfunction with decreased muscle tone. The most common causes of syncope noted in almost 15% of children are neurocardiogenic. This group includes vasovagal, carotid sinus reflexive, situational (coughing, dysphagia, micturation and defecation disturbances) and post-exercise syncope. Another group is represented by orthostatic syncope that may be triggered by primary and secondary dis-autonomy, decreased blood volume (hemorrhage, diarrhea, Addison's disease), some medications and substances of abuse (alcohol). An important group, accounting for 2%-6% of all cases, are cardiogenic syncope, caused mainly by congenital/acquired obstructive cardiac sub- and valvar heart defects, various cardiomyopathies, some heart tumors (e.g. myxoma), exudative pericarditis, pulmonary embolus and hypertension, congenital and acquired coronary anomalies, various significant brady-tachyarrhythmias (sick sinus syndrome, supra- and ventricular tachycardias, congenital and acquired atrio-ventricular blocks). Subclavian steal syndrome as the cause of syncope is exceptional in children. Syncope does not include loss of consciousness due to neurological and metabolic (hypoglycemia) causes, hypoxia, hyperventilation with hypocapnia or CO intoxication. Differential diagnosis should also include pseudo-syncope (hysteria). Preliminary diagnostic management should include a detailed medical history, including family history, on the frequency and circumstances of syncope, sudden deaths, a physical exam with orthostatic assessment of peripheral blood pressure and standard ECG (heart rate, intraventricular and atrioventricular conduction defects, cardiac hypertrophy, arrhythmias, L-QT, changes in ST-T). Further specialist tests depend on preliminary findings.

[Cardiac syncope in children]. / Omdlenia kardiogenne u dzieci.

INTRODUCTION: Syncope are serious problems in paediatrics. Approximately 15% of children and adolescents at the age of 8-18 years experience at least one episode of syncope. Neurocardiogenic syncope are the most common (60-80%). Cardiogenic syncope are rare (6%), although they require special attention due to their background. AIM OF THE STUDY: Evaluation of incidence, causes, methods of treatment and prognosis in cardiogenic syncope in children and adolescents. MATERIAL AND METHODS: Retrospective analysis was made in 18 patients with syncope and different pathology of cardiovascular system. Patients were chosen among 766 children treated in the University Hospital for Children in Cracow from January 2005 to June 2006 due to syncope or pre-syncope. The patients were divided into 2 groups depending on the main cause of syncope: Gr I n = 6 due to arrhythmias without structural heart disorders and Gr II n = 12 due to heart diseases or defects. In all patients physical exam and additional test were analysied carefully (ECG, Holter study, chest X ray, ECHO, angio-TK in 1 patient, and catheterisation with angiography in 3 children). RESULTS: Cardiogenic syncope appeared more frequently in children with structural abnormalities in the heart (Gr II--12 pts/ 66%), rather than in children with arrhythmias (Gr I--6 pts / 33%). Family history was positive in both groups in 17%. Median age at the moment of first episode was 10.3 y +/- 5.0 in Gr I and 12.8 y +/- 3.0 in Gr II. Syncope in Gr II were frequently (33%) initiated by an effort or stress. In Gr I physical examination did not reveal serious symptoms except for irregularity of heart rate, and general condition of children was good (NYHA I). In 5 pts (58%) in Gr II heart murmur and prominent impulse of the left ventricle were found. Symptoms of congestive heart failure were observed in 4 pts (33%) and their condition was poor (III/IV class according to NYHA). In ECG and/or Holter study in Gr I arrhythmias and/or long QTc were found. Pharmacotherapy was sufficient in treatment of serious arrhythmias and prophylaxy of syncope. In Gr II in most cases hypertrorepolarization abnormalities were found. In these children treatment was multidirectional and included both antiarrhythmic drugs, implantation of cardioverter defibrillator (ICD), operation and even heart transplantation. CONCLUSIONS: Cardiogenic syncope are rare causes of loss of consciousness and indicate on serious pathology in the cardiovascular system. Heart structural diseases or defects influence severity on clinical course, complex treatment and serious prognosis while in children with arrhythmias pharmacotherapy is effective and prognosis is usually good.

Contemporary outcomes of catheter ablation of accessory pathways: complications and learning curve.

BACKGROUND AND AIM: The aim of this study was to examine contemporary results of accessory pathway (AP) ablation in a sizeable number of patients, focusing on periprocedural complications and the learning curve. METHODS: We performed a retrospective cohort study of consecutive AP ablation procedures at three centresby the same operator. In total 629 electrophysiological studies and 610 AP ablation procedures were performed in 570 patients (age: 33 ± 18.9 years). RESULTS: There was one (0.16%) serious and there were 14 (2.3%) minor periprocedural complications. Five hundred and ninety APs were successfully ablated: single/multiple procedure success was 93.4%/96.7%, while the average fluoroscopy time was 13.5 min. There was significantly higher success and less fluoroscopy use with increased experience, while periprocedural complications seemed evenly distributed over the years. The learning was most pronounced for the first 120 cases. However, the learning curve fully flattened only after approximately 400 ablations. CONCLUSIONS: This study suggests that in the modern era AP ablation is safer than it was in the first two decades after the introduction of catheter ablation of APs. Perhaps, in experienced centres there should be a lower threshold for referring asymptomatic/mildly symptomatic patients with pre-excitation for electrophysiological study.