Associations between Selected ADRB1 and CYP2D6 Gene Polymorphisms in Children with Ventricular and Supraventricular Arrhythmias

Background and Objectives: Tachycardia is a common cardiovascular disease. Drugs blocking β1-adrenergic receptors (ADRB1) are used in the therapy of arrhythmogenic heart diseases. Disease-related polymorphisms can be observed within the ADRB1 gene. The two most important are Ser49Gly and Arg389Gly, and they influence the treatment efficacy. The family of the cytochrome P450 system consists of the isoenzyme CYP2D6 (Debrisoquine 4-hydroxylase), which is involved in phase I metabolism of almost 25% of clinically important drugs, including antiarrhythmic drugs. A study was conducted to detect the ADRB1 and CYP2D6 gene polymorphisms. Materials and Methods: The material for the test was whole blood from 30 patients with ventricular and supraventricular tachycardia and 20 controls. The samples were obtained from the Department of Pediatric Cardiology. The first to be made was the extraction of DNA using a GeneMATRIX Quick Blood DNA Purification Kit from EURx. The selected ADRB1 and CYP2D6 gene polymorphisms were detected by high-resolution melting polymerase chain reaction (HRM-PCR) analysis. Results: Based on the analysis of melt profile data for each PCR product, the identification of polymorphisms was carried out. Heterozygotes and homozygotes were found in the examined alleles. Conclusions: The frequency of the Arg389Gly polymorphism differs statistically significantly between the control group and patients with supraventricular and ventricular arrhythmias, as well as between these two groups of patients. Moreover, the Arg389Gly polymorphism was statistically more prevalent in the group of girls with SVT arrhythmia compared to girls with VT. A few carriers of homozygous and heterozygous systems of the S49G polymorphism were detected among patients with arrhythmias, as well as control group. The percentage of individuals carrying the CYP2D6 4 allele as either homozygous or heterozygous was observed in the study and control groups. The high prevalence of the CYP2D6*4 allele carriers in both groups prompts the optimization of beta-1 blocker therapy.

Life situation of a caregiver of a child with congenital heart defect and/or other cardiac problems: structure and preliminary validation of a new questionnaire

Background

Illness in a child with cardiac disease causes stress, brings additional responsibilities, reorganizes family life, and changes the functioning of the family.

Aim

This study aimed to validate a new questionnaire evaluating the life situations of caregivers/parents of children with congenital heart disease (CHD) and/or other cardiac diseases (OCD).

Materials and methods

The questionnaire comprised 10 questions aimed at assessing the life situation of an ill child's caregiver in two main areas: personal and spiritual. The total score of the questionnaire assessing the life situation of the caregiver of a child with a CHD and/or OCD can range from 0 to 32 points, with scores <26 indicating a poor, 25 to 32 indicating an average, and >32 indicating a good level of life situation in the personal sphere of the caregiver. The questionnaire was assessed using Cronbach's alpha tests, and repeatability was assessed using Cohen's Kappa test (retest) within a time interval of two to 4  weeks from the first measurement.

Results

The research covered 50 respondents. Cohesion in the personal sphere obtained a satisfactory value of Cronbach's α = 0.72, in the spiritual sphere: Cronbach's α = 0.83, and the result common for both sections was: Cronbach's α = 0.66.

Conclusion

The Life Situation Assessment Questionnaire for caregivers of children with CHD and OCD is a reliable and homogeneous tool for measuring the functioning of parents in the event of a child's illness.

A tendency to worse course of multisystem inflammatory syndrome in children with obesity: MultiOrgan Inflammatory Syndromes COVID-19 related study

BACKGROUND

A new disease entity called multisystem inflammatory syndrome in children (MIS-C) is a rare consequence of COVID-19 infection. The pathophysiology and risk factors of MIS-C are still unclear, and the clinical manifestation ranges from milder forms to cases needing intensive care unit treatment. Based on available data, obesity is linked to pro-inflammatory stimulation. Moreover, several studies showed that obesity could play a role in COVID-19 severity and its comorbidities among the adult and children's populations. This study aimed to investigate the influence of overweightedness/obesity in childhood for the course of MIS-C in Poland.

METHODS

This study presented data from the national MultiOrgan Inflammatory Syndromes COVID-19 Related Study (MOIS-CoR) collected between 4 March 2020 and 20 February 2021. Of the 371 patients that met the Polish MIS-C criteria, 306 were included for further analysis.

RESULTS

Children who are obese (OB with body mass index (BMI) ≥95th percentile) and overweight (OV with BMI ≥85th percentile but <95th percentile) (28 and 49 patients, respectively) represented 25.1% (n=77) of all recruited patients. Complete recovery at the time of discharge presented in 93% of normal body weight (NW) participants and 90% of OV children (p>0.05). Among OB children, 76% recovered fully, which differed from the NW group (p=0.01). Calculated odds ratio (OR) of incomplete recovery for OB children was 4.2. Irrespective of body weight, there were no differences (p>0.05) in the length of hospitalization and the duration of symptoms (for OB, 13 and 16.5 days; for OV and NW, 10 and 14 days, respectively), as well as in the frequency of cardiovascular abnormalities, necessity of oxygen therapy (OB, 26.9%; OV, 23.9%; and NW, 20.7%), and intravenous immunoglobulin and glucocorticosteroid (GCS) treatment.

CONCLUSION

The higher risk of incomplete recovery and observed tendency toward a worsening course of MIS-C in patients with obesity suggest the need for further studies to confirm and understand our findings.

Diagnostic Value of the TpTe Interval in Children with Ventricular Arrhythmias

BACKGROUND

The changes in the period of ventricular repolarization, i.e., QT interval, QTp (Q-Tpeak) and TpTe interval (Tpeak-Tend), make it possible to assess the electrical instability of the heart muscle, which may lead to the development of life-threatening ventricular arrhythmia. The aim of the study was to determine and evaluate the use of differences in T-wave morphology and durations of repolarization period parameters (QT, TpTe) in resting ECGs for children with ventricular arrhythmias.

METHODS

The retrospective analysis was made of the disease histories of 80 examined children with resting ECGs, which were admitted to the Children's Cardiology Department. The study group consisted of 46 children aged 4 to 18 with ventricular arrhythmias and the control group consisted of 34 healthy children between 4 and 18 years of age, with no arrhythmias.

RESULTS

The duration of the TpTe interval was significantly (p < 0.001) longer in the group of children with ventricular arrhythmia with abnormal T-wave (bactrian/bifid, humid/biphasic) compared to the TpTe interval in children with ventricular arrhythmia with the normal repolarization period. The duration of the TpTe (p < 0.001), QTcB (p < 0.001) and QTcF (p < 0.001) intervals were significantly longer in the group of children with ventricular arrhythmias and with abnormal T-wave compared to the values of the TpTe, QTcB, and QTcF intervals of the control group with normal morphology of the repolarization period. Only the duration of the TpTe interval was significantly (p = 0.020) longer in the group of children with ventricular arrhythmia without clinical symptoms.

CONCLUSIONS

Children with benign ventricular arrhythmias recorded on a standard ECG with prolonged TpTe and QT intervals and abnormal T-wave morphology require systematic and frequent cardiac check up with long term ECG recordings due to the possibility of future more severe ventricular arrhythmias. Further follow-up studies in even larger groups of patients are necessary to confirm the values of these repolarization parameters in clinical practice.

Prolongation of Electrocardiographic T Wave Parameters Recorded during the Head-Up Tilt Table Test as Independent Markers of Syncope Severity in Children

The head-up tilt table test (HUTT) with the upright phase is used to help determine an imbalance of the sympathetic nervous system that is related to abnormal electrocardiographic repolarization in children with vasovagal syncope (VVS) and also in patients with the long QT syndrome (LQTS). The study attempted to evaluate T wave morphology and QT and TpTe (Tpeak-Tend) intervals recorded in ECG during the HUTT for a more accurate diagnosis of children with VVS. The group investigated 70 children with a negative HUTT result: 40 patients with VVS and 30 healthy volunteers without syncope. The RR interval as well as TpTe, and QTc intervals were measured in lead V5 of electrocardiogram (ECG) on admission to the hospital and during three phases of the HUTT. In syncopal children, which included 23 children with bifid or flat T waves and 17 patients with normal T waves in the upright phase, the QTc and TpTe were longer (p < 0.001) compared to the other test phases and longer (p < 0.001) than in the control group, respectively, with the risk of arrhythmias. Only in the control group, the TpTe was shorter (p < 0.001) in the upright phase than in the other tilt phases. The TpTe in the upright phase (>70 ms) was a good discriminator, and was better than the QTc (>427 ms). Prolongation of electrocardiographic TpTe and QT intervals, in addition to the (abnormal T wave morphology recorded during the HUTT, are helpful for identifying VVS children more predisposed to ventricular arrhythmias with a latent risk of LQTS. Further studies are required to assess the value of these repolarization parameters in clinical practice.

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.

The Differences in the Diagnostic Profile in Children with Vasovagal Syncope between the Result of Head-Up Tilt Table Test

(1) Background: The features characterizing vasovagal syncope (VVS) are an important factor in the correct evaluation of diagnostic risk stratification in children and adolescents. The aim of the study was to determine the value of identifying the clinical characteristics in children with VVS. (2) Methods: We made a retrospective analysis of the medical records of 109 children with diagnosed VVS. We investigated the specific characteristics of syncope in children with VVS including the positive VVS (+) and negative VVS (−) result of the Head-Up Tilt Table Test (HUTT). (3) Results: We did not observe significant differences in the prodromal symptoms of VVS with HUTT response. In addition to typical prodromal symptoms, no difference in statistically reported palpitations (35/109 or 32.1%) and chest discomfort (27/109 or 27.7%) were recorded. Fear–pain–stress emotions as circumstances of syncope were more often reported by children with a negative HUTT (p = 0.02). Cramps–contractures (p = 0.016) and speech disorders (p = 0.038) were significantly higher in the group with negative HUTT. (4) Conclusions: There is a close relationship in the diagnostic profile between the negative and positive results of head-up tilt table test in children with vasovagal syncope.

Feasibility and performance of catheter ablation with zero-fluoroscopy approach for regular supraventricular tachycardia in patients with structural and/or congenital heart disease

Patients with structural heart disease (SHD) are more difficult to ablate than those with a structurally healthy heart. The reason may be technical problems. We compared periprocedural data in unselected patients (including SHD group) recruited for zero-fluoroscopy catheter ablation (ZF-CA) of supraventricular arrhythmias (SVTs).Consecutive adult patients with atrioventricular nodal reentry tachycardia (AVNRT), accessory pathways (AP), atrial flutter (AFL), and atrial tachycardia (AT) were recruited. A 3-dimensional electroanatomical mapping system (Ensite Velocity, NavX, St Jude Medical, Lake Bluff, Illinois) was used to create electroanatomical maps and navigate catheters. Fluoroscopy was used on the decision of the first operator after 5 minutes of unresolved problems.Of the 1280 patients ablated with the intention to be treated with ZF approach, 174 (13.6%) patients with SHD (age: 58.2 ± 13.6; AVNRT: 23.9%; AP: 8.5%; AFL: 61.4%; and AT: 6.2%) were recruited. These patients were compared with the 1106 patients with nonstructural heart disease (NSHD) (age: 51.4 ± 16.4; AVNRT: 58.0%; AP: 17.6%; AFL: 20.7%; and AT: 3.7% P ≤ .001). Procedural time (49.9 ± 24.6 vs 49.1 ± 23.9 minutes, P = .55) and number of applications were similar between groups (P = 0.08). The rate of conversion from ZF-CA to fluoroscopy was slightly higher in SHD as compared to NSHD (13.2% vs 7.8%, P = .02) while the total time of fluoroscopy and radiation doses were comparable in the group of SHD and NSHD (P = .55; P = .48).ZF-CA is feasible and safe in majority of patients with SHD and should be incorporated into a standard approach for SHD; however, the procedure requires sufficient experience.

Electrocardiographic T-wave parameters in families with long QT syndrome

BACKGROUND

T-wave parameters, especially the Tpeak-Tend interval (TpTe), reflect the total dispersion of repolarization, whose amplification may lead to the development of life-threatening ventricular arrhythmias observed in the long QT syndrome (LQTS).

OBJECTIVES

The study attempted to evaluate QT, QTp (Q-Tpeak) and TpTe (Tpeak-Tend) intervals in unaffected and affected blood relatives of children with clinically confirmed LQTS as well as to determine whether the values of these repolarization parameters may be used in clinical practice.

MATERIAL AND METHODS

The study group included 47 affected blood relatives (27 LQTS1 and 20 LQTS2) and 68 unaffected family members without clinically confirmed LQTS symptoms. The TpTe, QT and QTp intervals were measured manually in the lead V5 of standard ECGs and corrected using Bazett's and Fridericia's formulas.

RESULTS

The RR, QT, QTp and TpTe intervals with their corrected values were significantly longer (p < 0.0001) in the affected subjects than in the unaffected subjects and, similarly, in LQTS1 and LQTS2 patients compared with the unaffected family members. The TpTe interval in LQTS2 showed only a tendency to be longer compared to LQTS1, but did not reach statistical significance (p = 0.0933). For affected blood relatives, only the TpTe interval (p < 0.0409) and QT interval, corrected with Bazett's (p < 0.0393) and Fridericia's (p < 0.0495) formulas, enabled differentiation between LQTS1 (mean TpTe = 103 ±15) and LQTS2 women (mean TpTe = 106 ±17). Moreover, there were statistically significant differences (p < 0.05) in the TpTe interval between the 6 sex subgroups: unaffected women and men as well as women and men with LQTS1 and LQTS2.

CONCLUSIONS

The electrocardiographic Tpeak-Tend parameter, in addition to the QT interval, is helpful in identifying affected blood relatives of children with LQTS, particularly for the group of LQTS1 and LQTS2 women. Further studies are required to assess the clinical importance of the TpTe interval in families with long QT syndrome.

Early results of aortic arch reconstruction and bilateral pulmonary artery banding: modification of the Norwood operation for treatment of hypoplastic left heart syndrome

BACKGROUND

In the period from 2003 to the end of 2015, 96 Norwood I procedures were performed in the Paediatric Heart Surgery Department in Katowice, Poland, in children with hypoplastic left heart syndrome (HLHS).

AIM

This paper presents a retrospective analysis of early surgical results.

METHODS

The patients consisted of two groups: group I included 59 children operated on in the years 2003-2012, in whom the stage I Norwood procedure with the Sano modification was performed with the aortic arch reconstructed by use of a ho-mogenous pulmonary artery patch or a bovine pericardial patch. Group II included 37 children after our modification of the Norwood I procedure, in which the aortic arch was reconstructed with an extracellular matrix patch and bilateral pulmonary artery banding was done.

RESULTS

Aortic cross-clamping time was significantly shorter in group II (mean 52; range 38-62 min) than in group I (mean 57; range 39-72 min; p < 0.009). Eighteen (30.5%) children in group I and six (16.2%) in group II died. Although this dif-ference did not reach statistical significance (p = 0.12), it suggested that improved outcomes with the modified procedure are possible. The cause of death in group I was significantly more frequently due to massive postoperative bleeding (n = 6; 33.3%) than in group II (n = 1; 16.7%; p = 0.046).

CONCLUSIONS

The introduction of this new surgical technique reduced postoperative bleeding rates, shortened the operation time, and might improve the mortality rate in the first-stage surgical treatment of children with HLHS.

Preoperative single ventricle function determines early outcome after second-stage palliation of single ventricle heart

Background

Second-stage palliation with hemi-Fontan or bidirectional Glenn procedures has improved the outcomes of patients treated for single-ventricle heart disease. The aim of this study was to retrospectively analyze risk factors for death after second-stage palliation of single-ventricle heart and to compare therapeutic results achieved with the hemi-Fontan and bidirectional Glenn procedures.

Material and methods

We analyzed 60 patients who had undergone second-stage palliation for single-ventricle heart. Group HF consisted of 23 (38.3%) children who had been operated with the hemi-Fontan method; Group BDG consisted of 37 (61.7%) who had been operated with the bidirectional Glenn method. The analysis focused on 30-day postoperative mortality rates, clinical and echocardiographic data, and early complications.

Results

The patients’ ages at the time of repair was 33 ± 11.2 weeks; weight was 6.7 ± 1.2 kg. The most common anatomic subtype was hypoplastic left heart syndrome, in 36 (60%) patients. The early mortality rate was 13.3%. Significant preoperative atrioventricular valve regurgitation, single-ventricle heart dysfunction, pneumonia/sepsis, and arrhythmias were associated with higher mortality rates after second-stage palliation. Multivariate analysis identified significant preoperative single-ventricle heart dysfunction as an independent predictor of early death after second-stage palliation. No differences were found in the analyzed variables after bidirectional Glenn compared with hemi-Fontan procedures.

Conclusion

Significant preoperative atrioventricular valve regurgitation, arrhythmias and pneumonia/sepsis are closely correlated with mortality in patients with single-ventricle heart after second-stage palliation. Preoperative significant single-ventricle heart dysfunction is an independent mortality predictor in this group of patients. There are no differences in clinical, echocardiographic data, or outcomes in patients treated with the hemi-Fontan compared with bidirectional Glenn procedures.

Risk factors of immunoglobulin resistance and coronary complications in children with Kawasaki disease

BACKGROUND

The risk of immunoglobulin resistance is still likely to occur in Kawasaki disease (KD) despite adequate treatment. The Kobayashi score (KS) is used to predict unresponsiveness to treatment although the usefulness of the score in populations other than Asian seems to be debatable.

AIM

The analysis of clinical and laboratory parameters predisposing to immunoglobulin resistance and coronary complica-tions in children hospitalised due to KD.

METHODS

The data of children hospitalised due to KD between 2003 and 2016 underwent analysis. Clinical and laboratory parameters were analysed, including all parameters present in KS in relation to the risk of intravenous immunoglobulin (IVIG) resistance and the occurrence of coronary complications in the form of aneurysms and dilatations.

RESULTS

Seventy-three children (51 boys; aged 1.5-135 months) with KD were hospitalised. In eight (11%) patients IVIG re-sistance was observed. We reported aneurysms or coronary dilatations in 13 (17.8%) children. The criterion for increased risk of IVIG resistance based on KS (≥ 4 points) was fulfilled by 21 (29%) children. Resistance to IVIG and coronary complications were observed in four (19.1%) and two (9.5%) children with the score ≥ 4 points, respectively, and four (7.7%) and 11 (21.6%) from the group < 4 points in KS, respectively. The prevalence of IVIG resistance and coronary artery complications was not different between the group with ≥ 4 and the group with < 4 points (p = 0.22, p = 0.32, respectively). A higher risk of IVIG resistance was confirmed in children with a longer duration of fever (13.0 days with IVIG resistance vs. 9.2 days with a good response to IVIG, p = 0.04). For the prediction of the occurrence of coronary artery aneurysms the following were of great importance: the day of diagnosis (which was usually the day of the beginning of treatment), the number of symptoms, and the maximal platelet count (p = 0.001; p = 0.019 and p = 0.026, respectively).

CONCLUSIONS

In our study population we did not demonstrate the usefulness of KS to predict IVIG resistance or the risk of the occurrence of coronary artery aneurysms. However, prolonged fever, late diagnosis, poorly symptomatic course of the disease, and a high platelet count at the time of the follow-up remain independent risk factors.

Influence of the hemodynamic status of multiorgan donors on long-term kidney graft survival--a multivariable analysis

BACKGROUND

The quality of transplanted organ and timing of the initiation of its effective function depends on many factors potentially causing graft dysfunction. The aim of this study was to evaluate the influence of the cardiovascular status of multiorgan donors on the long-term kidney graft survival over a 15-year observation period.

METHODS

In 2007, the authors of this study published a multicenter prospective study evaluating the influence of the hemodynamic status of multiorgan donors on the early function of transplanted kidney. The results of that study showed that mean arterial pressure, central venous pressure, and pulmonary capillary wedge pressure values of the donor importantly influence the frequency of delayed graft function after renal transplantation. The present analysis covers the effect of the donor's hemodynamic status parameters on graft function time within the 15-year observation period. Univariate and multivariate analyses using the Cox regression proportional hazard model were performed to evaluate the prognostic parameters for overall survival and renal graft survival time. P < .05 was considered to be significant.

RESULTS

The univariate analysis showed a significantly shorter time of graft survival in the group of recipients who had a kidney retrieved from donors with lower pulmonary capillary wedge pressure values (P = .038) and lower cardiac index values (P = .039). The same results were obtained for the multifactorial Cox logistic regression analysis.

CONCLUSIONS

The filling of the intravascular bed of the donor as determined by pulmonary capillary wedge pressure and maintained donor tissue perfusion as determined by cardiac index, impose important factors influencing long-term kidney graft survival.

Feasibility of implementation of a "simplified, No-X-Ray, no-lead apron, two-catheter approach" for ablation of supraventricular arrhythmias in children and adults

INTRODUCTION

Although the "near-zero-X-Ray" or "No-X-Ray" catheter ablation (CA) approach has been reported for treatment of various arrhythmias, few prospective studies have strictly used "No-X-Ray," simplified 2-catheter approaches for CA in patients with supraventricular tachycardia (SVT). We assessed the feasibility of a minimally invasive, nonfluoroscopic (MINI) CA approach in such patients.

METHODS

Data were obtained from a prospective multicenter CA registry of patients with regular SVTs. After femoral access, 2 catheters were used to create simple, 3D electroanatomic maps and to perform electrophysiologic studies. Medical staff did not use lead aprons after the first 10 MINI CA cases.

RESULTS

A total of 188 patients (age, 45 ± 21 years; 17% <19 years; 55% women) referred for the No-X-Ray approach were included. They were compared to 714 consecutive patients referred for a simplified approach using X-rays (age, 52 ± 18 years; 7% <19 years; 55% women). There were 9 protocol exceptions that necessitated the use of X-rays. Ultimately, 179/188 patients underwent the procedure without fluoroscopy, with an acute success rate of 98%. The procedure times (63 ± 26 vs. 63 ± 29 minutes, P > 0.05), major complications (0% vs. 0%, P > 0.05) and acute (98% vs. 98%, P > 0.05) and long-term (93% vs. 94%, P > 0.05) success rates were similar in the "No-X-Ray" and control groups.

CONCLUSIONS

Implementation of a strict "No-X-Ray, simplified 2-catheter" CA approach is safe and effective in majority of the patients with SVT. This modified approach for SVTs should be prospectively validated in a multicenter study.

Dyspnoea related to pre-excitation during sinus rhythm as a new indication for catheter ablation

BACKGROUND

Patients with pre-excitation without arrhythmic symptoms are diagnosed as Wolff-Parkinson-White (WPW) pattern.

AIM

To evaluate the efficacy of radiofrequency ablation (RFA) in patients with a WPW pattern and reported dyspnoea.

METHODS

Five patients (four adults and one adolescent, all female, age 33 ± 15 years) with a WPW pattern were referred due to dyspnoea and exercise intolerance. None had a history of paroxysmal syncope, pre-syncope, dizziness or palpitation. Before and after RFA, additional tests were used to exclude organic diseases of the pulmonary vessels, heart and lung, as well as bronchial hyperreactivity and metabolic diseases. Cardiopulmonary exercise test (CPET), echocardiography, time of forced expiration, baseline dyspnoea index (BDI), and transition dyspnoea index (TDI) were included into an objective evaluation of breath pattern.

RESULTS

In all investigated patients, no arrhythmia was inducible during the electrophysiology study. The time of forced expiration increased immediately after RFA from 15.8 ± 2.9 to 29.2 ± 4.4 s (p < 0.001). The BDI score before RFA was 6.7 ± 1.9 and the TDI score after RFA showed a significant improvement: 8.0 ± 1.2 (p < 0.05). CPET revealed significant improvement in cardiopulmonary capacity after RFA in all cases: peak oxygen consumption [mL/kg/min]: 31.1 ± 7 vs. 42.6 ± 9.6 (p = 0.014); peak exercise minute ventilation [L/min]: 60.0 ± 19.9 vs. 82.0 ± 27 (p = 0.006); peak exercise tidal volume [L]: 1.56 ± 0.25 vs. 2.04 ± 0.24 (p = 0.002); ratio dead space/tidal volume at the end of exercise: 28 ± 2.6 vs. 25 ± 2.3 (p = 0.005).

CONCLUSIONS

Dyspnoea during sinus rhythm in women with pre-excitation may be considered to be an evaluation criterion before RFA.

[Paediatric echocardiography in clinical practice. 2012 Recommendations of the Echocardiography Working Group of the Polish Cardiac Society]

Echocardiography has become the primary imaging tool in the diagnosis and assessment of cardiological disorders in children. The purposes of this paper are to describe indications for paediatric echocardiography, define optimal instrumentation and laboratory setup for paediatric echocardiographic examinations and establish a baseline list of recommended measurements to be performed in a complete pediatric echocardiogram.

Age-and sex-dependent mRNA expression of KCNQ1 and HERG in patients with long QT syndrome type 1 and 2

INTRODUCTION

The main goal of this study was to examine the patient age and sex dependent expression of KCNQ1 and HERG genes that encode potassium channels responsible for the occurrence of long QT syndrome (LQTS).

MATERIAL AND METHODS

The study enrolled 43 families whose members suffered from LQTS type 1 (LQTS1) or 2 (LQTS2) or were healthy. The study attempted to prove that β-actin is a good endogenous control when determining the expression of the studied genes. Examination of gene expression was achieved with quantitative real-time PCR (QRT-PCR). Expression of the investigated genes was inferred from the analysis of the number of mRNA copies per 1 μg total RNA isolated from whole blood.

RESULTS

Significantly lower KCNQ1 and KCNH2 mRNA levels in healthy females than healthy males were observed (p = 0.032; p = 0.02). In male patients both transcripts were expressed at a lower level (p = 0.0084; p = 0.035). The comparison of transcriptional activity of KCNQ1 and KCNH2 in healthy adults and children revealed higher KCNQ1 and lower KCNH2 mRNA levels in healthy adults (p = 0.033; p = 0.04), higher KCNQ1 and lower KCNH2 mRNA levels in adult patients below 55 years old than in adults over 55 years old (p=0.036; p = 0.044), and significantly higher KCNQ1 and lower KCNH2 mRNA levels in adult patients (over 55 years) than in paediatric patients (below 15 years) (p=0.047; p = 0.08).

CONCLUSIONS

The results support the hypothesis that KCNQ1 and HERG gene expression is influenced by age and gender in human patients with long QT syndrome and in healthy subjects.

Expression of genes KCNQ1 and HERG encoding potassium ion channels Ikr, Iks in long QT syndrome

BACKGROUND

The KCNQ1 and HERG genes mutations are responsible for specific types of congenital long QT syndrome (LQT).

AIM

To examine the expression of KCNQ1 and HERG genes that encode potassium channels (rapid and slow) responsible for the occurrence of particular types of LQT syndrome. The study also attempted to prove that beta-actin is a good endogenous control when determining the expression of the studied genes.

METHODS

The study enrolled six families whose members suffered from either LQT1 or LQT2, or were healthy. Examination of gene expression was achieved with quantitative PCR (QRT-PCR). Expression of the investigated genes was inferred from the analysis of the number of mRNA copies per 1 mg total RNA isolated from whole blood. On the basis of KCNQ1 gene expression profile, the presence of, or absence of, LQT1 could be confirmed.

RESULTS AND CONCLUSIONS

The study revealed a statistically significant difference (p = 0.031) between the number of KCNQ1 gene copies in patients and healthy controls. On the basis of HERG (KCNH2) gene expression profile, patients with LQT2 cannot be unequivocally differentiated from healthy subjects (p = 0.37).

The diagnosis, clinical course and follow-up of children with cardiac tumours - a single-centre experience

BACKGROUND

Rhabdomyoma is the most frequent primary cardiac tumour in children (about 50% of all cardiac neoplasms in this population). Fibroma, myxoma, teratoma and haemangioma are less frequent.

AIM

To investigate the clinical presentation, diagnosis and follow-up of children diagnosed with cardiac tumours in our department between 1993 and 2008.

METHODS

In the 15-year review we found 9 cases of cardiac tumours, confirmed in echo scan in every case and pathomorphologically in 5 out of 9 cases.

RESULTS

Cardiac tumours were found in six boys and three girls, usually in the neonatal period. Cardiac murmur was the most common clinical symptom (4 cases). Two children were symptom-free. Out of the remaining children, two had circulatory failure and one had arrhythmia. Five children were operated on: three cases of rhabdomyoma, one fibroma and one teratoma. In 3 children who did not undergo surgery, the most probable diagnosis was rhabdomyoma. The follow-up (possible in 8 out of 9 cases, mean 7 years) showed that six children developed regularly and in two cases neurological abnormalities appeared.

CONCLUSIONS

In this series, primary cardiac tumours presented as murmurs or circulatory failure. Most children needed surgery. In most cases, pathomorphology revealed rhabdomyoma. Follow-up showed regular development in six out of nine cases.

N-terminal prohormone brain natriuretic peptide-proBNP levels in ventricular arrhythmias in children

BACKGROUND

Ventricular arrhythmias are the most common consequences of structural and functional heart diseases, but cases with no evident pathology are also observed. A parameter indicating asymptomatic circulatory failure could support decisions related to possible treatment of ventricular arrhythmias.

HYPOTHESIS

The study objective was the evaluation of N-terminal prohormone brain natriuretic peptide (NT-proBNP) levels in children with ventricular arrhythmias and an attempt to determine if this parameter may be used for diagnosis and prognosis of ventricular arrhythmias.

MATERIAL AND METHODS

The study population was comprised of 36 children age 5 to 17.5 years old with idiopathic ventricular arrhythmias (Group B) graded mild or potentially malignant; 29 patients with mild ventricular arrhythmias were included into Group B1; and 7 patients with potentially malignant cases into Group B2. In all the patients, NT-proBNP assays were performed.

RESULTS

The NT-proBNP levels in Groups B, B1, B2 and the control group (Group K) were as follows: 41.5 +/- 15.1 pg/mL, 35.5 +/- 18.5 pg/mL, 66.3 +/- 24.9 pg/mL and 31.5 +/- 15.1 pg/mL, respectively. Between the groups with and without arrhythmias (Group B vs Group K), no statistically significant differences in NT-proBNP levels were found. However, markedly higher NT-proBNP levels were shown in the children with potentially malignant arrhythmias (Group B2) compared to the patients with mild arrhythmias (B1) and the control group (Group K).

CONCLUSIONS

The level of NT-proBNP increases with the severity of ventricular arrhythmia. NT-proBNP assays can be helpful for diagnosing and grading the severity of ventricular arrhythmias.

Electrocardiographic abnormalities in young athletes with mitral valve prolapse

BACKGROUND

Mitral valve prolapse (MVP) is the most common primary valvular abnormality in a young population. In some individuals, MVP is silent or associated with palpitations, dizziness, chest pain, and abnormal electrocardiogram (ECG) repolarization with or without ventricular arrhythmias.

HYPOTHESIS

The aim of the present study was to assess the occurrence of the clinical and electrocardiographic abnormalities in young athletes with silent MVP.

METHODS

A group of 10 children, who have been sport training intensively, with preparticipation silent MVP were examined for symptoms and/or ECG abnormalities. The diagnosis of MVP was made by echocardiography.

RESULTS

Three athletes were asymptomatic at initial presentation. The other 7 athletes presented with symptoms. The QTc intervals > 440 msec were recorded in 2 athletes (1 with syncope). Abnormal ECG repolarization was found in 7 athletes (4 athletes were symptomatic and 3 were asymptomatic). A large variety of T-waves was registered in athletes who presented with symptoms. In asymptomatic athletes, the tall and flat T-waves were recorded.

CONCLUSIONS

Young athletes with MVP are often predisposed to electrocardiographic abnormalities of ventricular repolarization, which requires annual cardiologic evaluation.

[The new diagnostic tool - congenital heart diseases and the great arteries imaging using multislice computed tomography - case presentations]

Multislice computed tomography is an imaging method of internal organs including heart and vessels with the use of X-ray. The indications for computed tomography of the heart include also congenital heart diseases and the evaluation of the great arteries. Ultrasonography is a method of choice in heart evaluation. The authors show the possibilities of modern multislice computed tomography in congenital heart diseases imaging based on their own material.

Challenges of Diagnosis of Long-QT Syndrome in Children

We describe the clinical and genetic characteristics of the family, in which the diagnosis of LQT1 had been made. The electrocardiogram (ECG) characteristics of this patient indicated the likelihood of LQTS1. Polymorphic ventricular extrasystolies and episodes of polymorphic non-sustained ventricular tachycardia were confirmed by Holter ECG monitoring. On the exertional electrocardiogram polymorphic ventricular tachycardia (torsade de pointes) was recorded. Direct sequencing of both DNA strands revealed the absence of mutations or polymorphisms in the KCNQ1, HERG, and SCN5A genes.

Arrhythmogenic right ventricular dysplasia:clinical study

Arrhythmogenic right ventricular dysplasia (ARVD) is a complex arrhythmogenic cardiomyopathy, characterized by a partial or total replacement of the right ventricular myocytes by fatty and fibrous tissue. In this study, we present a case of ARVD in 17 year old girl, who was admitted to the hospital after syncope with ventricular arrhythmia. The echocardiography did not demonstrate structural cardiac abnormalities but the magnetic resonance recently showed thinning of the right ventricular wall. The girl was treated with the lidocaine, amiodarone and next, after radiofrequency catheter ablation she was receiving metoprolol. The girl has remained asymptomatic for four years of follow-up.

[Diagnostic problems with long QT syndrome in 5-year-old boy]

The authors described the case of 5-year-old boy, in whom a proper diagnosis was established after 19 months. In differential diagnosis, epileptic, tetanic and conversion seizures were taken into consideration.

[Syncope in children]

Syncope is a very common problem during childhood presenting to emergency departments. It generates a great deal of anxiety among children and their parents because of the fear that syncope are at risk for sudden death. Neurocardiogenic (vaso-vagal) syncope are the most common, while cardiac type are rare. The vaso-vagal syncope are secondary to irregularities in an autonomic reflex resulting in an abnormal relaxation of the blood vessels. This is non-life threatening form of syncope in differ cardiac type that can be very dangerous. In cardiac syncope causes can be secondary to obstruction to blood flow (Tetralogy of Fallot, cardiomyopathies, aortic stenosis), heart rhythm abnormalities (WPW, L-QTS, A-V block) as well as ischemic heart disease secondary to an anomalous coronary artery. The cardiac syncope are rare (6%) but the most inconvenient because they can be life-threatening.

[Vasovagal syncope--diagnostic difficulties in adolescents]

Consciousness disturbances in adolescents may be caused by different reasons. Among them, cardiologic and neurological backgrounds should be considered. The most important diagnostic tests the vasovagal syncopes are: tilt-table test, brain oxygenation measurement, routine and extended elektroencephalography. Performing of these examinations simultaneously may help in determining cause of symptoms. Our patient serves us as an example.

[Selected birth outcomes as prognostic determinants of hypertension in children]

BACKGROUND

About 5-15% of children suffer from hypertension. The influence of maturity and the physical development of newborns on primary hypertension has been recently underlined.

AIM

The aim of the study was to estimate the importance of low birth weight (< 10 percentiles--2500 g), low birth length (< 10 percentiles--50 cm), low Apgar score (< 4 points), prematurity (< 37 Hbd) in the developmental of hypertension in children.

METHODS

The project was conducted retrospectively in a group of 197 children with primary hypertension (aged 15.4 +/- 1.9) and 119 healthy children (aged 12.9 +/- 3.1) as the control group. The statistical analysis was performed with Epilnfo 6.0 procedures.

RESULTS

Male sex, overweight and family history of hypertension increased the risk of hypertension in a statistically significant way and the adequate estimated odds ratios were: OR = 3.69 (95% CI: 2.20-6.19), OR = 22.76 (95% CI: 6.61-94.12), OR = 21.87 (95% CI: 6.27-91.1). No influence of low birth weight, low birth length, low Apgar score and prematurity on primary hypertension was observed.

CONCLUSION

The results suggest that the role of low birth weight, low birth length, low Apgar score and prematurity in the development of hypertension in children is arguable. It also suggests the necessity to conduct epidemiologic surveys in more frequent groups of children.

[Implantation of cardiac pacemaker in children, author's experiences]

Cardiac pacemaker was implanted as a therapeutic method for children with atrio-ventricular block, sick sinus syndrome, LQT syndrome, cardio-depressive syncope. Twenty six children (aged 1-17) underwent pacemaker implantation or exchange of pacemaker and electrode. In nineteen cases cardiac peacemaker was implanted in the endocardial system; in the next seven cases epicardial system was required. The difference between the implantations depended on patient's age and the character of the disease. The single chamber peacemaker was implanted in twenty children, dual-chamber in six patients. There were no visible complications in follow up observation and constant heart stimulation can be considered as a safe way of children's severe bradycardia treatment.

[Late recognition of Kawasaki disease--difficulties in diagnosis]

Authors describe the case of 4 years old girl with Down syndrome, who was operated due to common atrio-ventricular canal and persistent Botalli's duct. Intermittent total atrio-ventricular block (without significant bradycardia) has been observed one year later and considered as a late postoperative block requiring no treatment. Kawasaki disease was diagnosed because of the presence of 4 out of 6 leading symptoms appearing in typical chronology (fever, mouth and throat inflammation, conjunctivitis, erythema with subsequent desquamation of skin on palms and feet). ECG revealed total atrio-ventricular block, however with significant bradycardia. ECHO showed aneurysms in both coronary arteries. Standard treatment of Kawasaki disease was administered (immunoglobulins, acetylsalicylic acid) and orciprenalin due to described cardiac block. Pacemaker was implanted because of bradycardia. The literature review showed that the treatment with immunoglobulins and aspirin can reduce the risk of coronary aneurysms development. On the other hand, identification of patients at risk coronary aneurysms development is not possible on the ground of biochemical blood analysis and physical signs. Thus, all the patients stricken should be treated with described above costly drugs (immunoglobulins). Finally, the algorithm of procedures in patients with coronary aneurysms was presented.

[Arterial hypertension among children and teenagers in the Upper Silesia]

Nowadays arterial hypertension is more frequently observed among children and teenagers then it used to be earlier. Arterial hypertension and obesity are more and more often the main sources of atherosclerosis. The purpose of this work was to assess the patients with the arterial hypertension treated in the Department of Pediatric Cardiology in Katowice in 2003. Patients' age, family history of hypertension, family background and parents' education were taken into consideration. Birth weight, BMI factor, all the sufferings reported by patients, blood pressure measurements results, ABPM, EKG parameters, ECHO+ Doppler parameters, exercise test results, fundus of the eye examination, laboratory investigation results, were also analyzed. Our results show that a positive family history is a very important factor in the development of arterial hypertension among children (44.7%). In our patients' cases the most frequent clinical symptoms are tachycardia (68%) and obesity (59.2%). In conclusion, children and teenagers with hypertension should be successfully treated and those with positive family history of hypertension should be taken under primary prevention in order to decrease the risk of cardiovascular complications.

[The significance of cardiac symptoms in patients referred to pediatric cardiology outpatient clinics]

OBJECTIVE

To determine the significance of cardiac symptoms in patients referred to paediatric cardiology outpatient clinics.

MATERIAL AND METHODS

All patients above l month of age referred to paediatric cardiac outpatient clinics between 01-Apr-2004 and 31-Dec-2004. Data was collected prospectively in Internet data base. Patients were divided into 3 groups: patients referred by paediatricians to regional paediatric cardiology outpatient clinic (group 1, N=3383), patients referred to Academic Paediatric Cardiac outpatient clinics by paediatricians (group 2, N= 7461) and by cardiologists (group 2a, N=793).

RESULTS

Average age of patients was 6.4 +/- 5.8 years. The most common reasons for referral included cardiac murmur, chest pain, syncope, earlier diagnosed congenital heart disease (CHD). The proportion of patients referred by cardiologists and paediatricians because of murmur was 30% vs 56%, arrhythmia 12.6% vs 8% and CHD 44% vs 8%. The percentage of the significant cardiac pathology in all groups (l/ 2/ 2a) was 38/35/76; in patients with chest pain -- 9/18/0; with syncope -- 56/70/80; with murmur -- 19/21/43; with CHD -- 68/69/93 and with arrhythmia -- 57/80/92.

CONCLUSIONS

l. There were no significant differences between patients referred by paediatricians from regional and academic outpatient cardiology clinics. 2. Isolated cardiac symptoms such as chest pain, cardiac murmur and syncope were caused by significant cardiac pathology only in about 1/5 cases. 3. Cardiac murmur was the most common reason for referral to cardiac outpatient clinic in younger patients, in older group syncope and arrhythmia were more frequent.