Regional variations in patient selection and procedural characteristics for cryoballoon ablation of atrial fibrillation in the cryo global registry.

BACKGROUND: Cryoballoon ablation is a well-established anatomical approach for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Although widely adopted, regional variations in standards of care have not been well characterized. METHODS: Patients with AF were enrolled in the Cryo Global Registry (NCT02752737) from May 2016 to Sept 2021 at 128 sites in 37 countries and treated with cryoballoon ablation according to local clinical practice. Baseline patient and procedural characteristics were summarized for 8 regions (Central Asia & Russia, East Asia, Europe, Middle East, North America, South Africa, South America, and Southeast Asia). Serious procedure-related adverse events (SAEs) were evaluated in a subset of patients with ≥ 7 days of follow-up. RESULTS: A total of 3,680 patients undergoing initial PVI for AF were included. Cryoballoon ablation was commonly performed in patients with paroxysmal AF. Mean age ranged from 47 ± 12 years in the Middle East to 64 ± 11 years in East Asia. Mean procedure time was ≤ 95 min in all regions. Average freeze duration ranged from 153 ± 41 s in Southeast Asia to 230 ± 29 s in Central Asia & Russia. Acute procedural success was ≥ 94.7% in all geographies. In 3,126 subjects with ≥ 7 days of follow-up, 122 procedure-related SAEs were reported in 111 patients (3.6%) and remained low in all regions. One procedure-related death was reported during data collection. CONCLUSIONS: Despite regional variations in patient selection and procedural characteristics, PVI using cryoballoon ablation was performed with high acute success and short procedural times around the world. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02752737.

[Prognostic significance of variant left common pulmonary vein after transcatheter pulmonary vein isolation]. / A variáns bal oldali közös tüdovéna prognosztikus jelentosége transzkatéteres tüdovéna-izolációt követoen.

INTRODUCTION: Left common pulmonary vein is the most common anatomical variant of pulmonary veins that may affect the outcome of pulmonary vein isolation. OBJECTIVE: Our aim was to compare procedural data and outcomes in patients with common trunk versus normal left atrial anatomy for radiofrequency and cryoballoon catheter ablation. METHOD: Data from patients who underwent pulmonary vein isolation for atrial fibrillation and had a preprocedural cardiac CT scan at our Institution between 01. 10. 2019 and 10. 03. 2022 were retrospectively evaluated. We defined a common trunk where the left superior and inferior pulmonary vein merged at least 5 mm before the left atrial ostium. RESULTS: From the study population (n = 210), data from 42 patients with a left common trunk (LCPV group) and 60 patients with normal left atrial anatomy (control group) were examined. No significant differences were found between the common trunk and the control group in terms of demographic data. There was no significant difference between the two groups in procedural data for radiofrequency and cryoballoon ablation (procedure time, fluoroscopy time, left atrial dwelling time, radiation dose). After radiofrequency ablation, the success rate at 1-year follow-up was 72.0% in the common trunk group and 76.2% in the control group (p = 0.659). For cryoballoon ablation, the success rate was 64.7% and 69.2% for common trunk and normal anatomy, respectively (p = 0.641). CONCLUSION: There was no significant difference in the procedural parameters and clinical outcome between patients with left common pulmonary vein and those with normal left atrial anatomy. Both radiofrequency and cryoballoon ablation techniques are well suited for this population. Orv Hetil. 2023; 164(4): 140-147.

Impact of first-line cryoablation for atrial fibrillation on healthcare utilization, arrhythmia disease burden and efficacy outcomes: real-world evidence from the Cryo Global Registry.

BACKGROUND: Cryoballoon ablation (CBA) is an effective first-line treatment for symptomatic atrial fibrillation (AF), as recently demonstrated by three randomized trials. This sub-analysis of the Cryo Global Registry aims to examine current clinical practices of first-line CBA. METHODS: AF patients treated with first-line CBA were compared to CBA in antiarrhythmic drug (AAD)-refractory patients at 12 months. Efficacy was examined using time-to-first atrial arrhythmia recurrence following a 90-day blanking period. Healthcare utilization was evaluated by repeat ablations and hospitalizations. Disease burden was examined by assessing quality of life (QOL) and patients' reporting of symptoms. RESULTS: Of 1394 patients, 433 (31.1%) were treated with first-line CBA, which was more frequent in high-volume centers. Serious procedure-related adverse event rates were similar. Efficacy at 12 months was higher in the first-line group (87.8 vs. 81.6%, HRunadj 0.64 (95% CI 0.47-0.88); p < 0.01) regardless of the centers' CBA experience; when controlling for baseline characteristics, the difference was not significant (HRadj 0.87 (95% CI 0.56-1.37); p = 0.55). No difference was observed in repeat ablations and hospitalizations between cohorts. First-line patients experienced a larger mean reduction in symptoms and were prescribed AADs at a lower rate at 12-month follow-up (9.7 vs. 29.9%). QOL improved in both cohorts from baseline to 12 months with no significant difference between groups (p = 0.29). CONCLUSIONS: In this global real-world experience, first-line CBA in patients with symptomatic AF is effective, with a larger symptom reduction compared with CBA after AAD failure and without a difference in healthcare utilization at mid-term follow-up. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02752737.

Cryoballoon Ablation for the Treatment of Atrial Fibrillation in Patients With Concomitant Heart Failure and Either Reduced or Preserved Left Ventricular Ejection Fraction: Results From the Cryo AF Global Registry.

Background Heart failure (HF) and atrial fibrillation (AF) often coexist; yet, outcomes of ablation in patients with AF and concomitant HF are limited. This analysis assessed outcomes of cryoablation in patients with AF and HF. Methods and Results The Cryo AF Global Registry is a prospective, multicenter registry of patients with AF who were treated with cryoballoon ablation according to routine practice at 56 sites in 26 countries. Patients with baseline New York Heart Association class I to III (HF cohort) were compared with patients without HF. Freedom from atrial arrhythmia recurrence ≥30 seconds, safety, and health care utilization over 12-month follow-up were analyzed. A total of 1303 patients (318 HF) were included. Patients with HF commonly had preserved left ventricular ejection fraction (81.6%), were more often women (45.6% versus 33.6%) with persistent AF (25.8% versus 14.3%), and had a larger left atrial diameter (4.4±0.9 versus 4.0±0.7 cm). Serious procedure-related complications occurred in 4.1% of patients with HF and 2.6% of patients without HF (P=0.188). Freedom from atrial arrhythmia recurrence was not different between cohorts with either paroxysmal AF (84.2% [95% CI, 78.6-88.4] versus 86.8% [95% CI, 84.2-89.0]) or persistent AF (69.6% [95% CI, 58.1-78.5] versus 71.8% [95% CI, 63.2-78.7]) (P=0.319). After ablation, a reduction in AF-related symptoms and antiarrhythmic drug use was observed in both cohorts (HF and no-HF), and freedom from repeat ablation was not different between cohorts. Persistent AF and HF predicted a post-ablation cardiovascular rehospitalization (P=0.032 and P=0.001, respectively). Conclusions Cryoablation to treat patients with AF is similarly effective at 12 months in patients with and without HF. Registration URL: https://www.clinicaltrials.gov; Unique Identifier: NCT02752737.

Safety of cryoballoon ablation for the treatment of atrial fibrillation: First European results from the cryo AF Global Registry.

BACKGROUND: Cryoballoon ablation for the treatment of patients with atrial fibrillation (AF) has been utilized in Europe for >15 years. OBJECTIVES: Report patient and procedural characteristics that influence the safety of cryoablation for the treatment of AF. METHODS: Patients enrolled in the prospective, multicenter Cryo AF Global Registry were treated at 38 European centers. Freedom from a ≥30s episode of AF/atrial flutter (AFL)/atrial tachycardia (AT) at 12-months and serious complications were analyzed. Univariate and multivariable models identified baseline patient and procedural characteristics that predicted a procedure-related complication. RESULTS: Of the 1418 subjects who completed an index procedure, the cohort was 62 ± 11 years of age, 37.7% female, and 72.2% paroxysmal AF (PAF). The mean procedure, left atrial dwell, and fluoroscopy times were 81 ± 34, 54 ± 25, and 14 ± 13 min, respectively. Among the 766 patients with 12-month follow-up, freedom from a ≥30 s AF/AFL/AT recurrence was 83.3% (95% CI: 79.8%-86.3%) and 71.6% (95% CI: 64.6%-77.4%) in patients with PAF and persistent AF. The serious procedure- and device-related adverse event rates were 4.7% and 2.0%. No baseline patient characteristic independently predicted a procedure-related adverse event; however, prolonged procedure duration (OR = 1.01 [95% CI: 1.00-1.01]), use of general anesthesia (OR = 1.71 [95% CI: 1.01-2.92]), and delivery of a cavotricuspid isthmus line (OR = 3.04 [95% CI: 1.01-9.20]) were each independently associated with the occurrence of a serious procedural safety event (all p < .05). CONCLUSIONS: Cryoballoon ablation is safe and effective in real-world use across a broad cohort of patients with AF.

Prospective evaluation of iatrogenic atrial septal defect after cryoballoon or radiofrequency catheter ablation of atrial fibrillation-"EVITA" study.

PURPOSE: Iatrogenic atrial septal defect (IASD) after catheter ablation (CA) for atrial fibrillation (AF) due to transseptal puncture (TSP) can occur. The aim of this prospective study was to describe the incidence of IASD and to detect any cerebrovascular accident (CVA) after radiofrequency (RF) and cryoballoon (CB) CA. METHODS: Between July 2014 and September 2016, 94 patients (pts) (RF; 48, CB; 46, 30 (31.9%) women, mean age = 60 ± 9.7 years) with paroxysmal AF were enrolled who underwent CA procedure for the first time. During RF ablation a single (n = 30, 62.5%) or double (n = 18, 37.5%) TSP was performed. Transoesophageal echocardiography before the procedure and at the 3-month and 12-month follow-up (FU) was accomplished. During the FU period, we evaluated the occurrence of any postprocedural CVA. RESULTS: At the 3-month FU, IASD was detected in 17/94 (18.1%) pts; in 9/48 (18.8%) pts in the RF while in 8/46 (17.4%) pts in the CB group (p = 0.866), all of them with left-to-right shunt. In the RF group, 6/30 (20%) pts with a single TSP while 3/18 (16.7%) pts in the double TSP group had IASD (p = 0.780). 14/17 (82.4%) IASDs showed high spontaneous closure rate at the 12-month FU. None of the pts died or suffered from CVA. CONCLUSION: Persistent IASD can occur rather frequently following AF CA. No significant difference was observed between the RF and CB techniques concerning the presence of IASD at 3-month. IASDs showed a high spontaneous closure rate. No cerebral thromboembolic event was observed in the 12-month FU period.

Long-term cerebral thromboembolic complications of transapical endocardial resynchronization therapy.

PURPOSE: Cardiac resynchronization therapy (CRT) is an established therapeutic option in selected heart failure patients (pts). However, the transvenous left ventricular (LV) lead implantation remains ineffectual in a considerable number of pts. Transapical LV (TALV) lead implantation is an alternative minimally invasive, surgical, endocardial implantation technique. The aim of the present prospective study is to determine the long-term outcome, including the cerebral thromboembolic complications, of pts who underwent TALV lead placement. METHODS: Twenty-six CRT candidates (19 men (78 %); mean age 61 ± 10 years) with a previously failed transvenous approach underwent TALV lead placement as a last resort therapy. The following data was collected: mortality rate, reoperation rate, and cerebrovascular event rate. Patients underwent a cerebral CT scan to determine any possible cerebrovascular event related to the presence of the TALV lead. RESULTS: Eleven out of 26 (47 %) patients survived after a median follow-up of 40 ± 24.5 months. Major acute ischemic stroke occurred in two cases, while in one case transient ischemic stroke was observed. Cerebral CT scan examination performed in asymptomatic patients revealed chronic ischemic lesions with minimal extension in two patients. Reoperation occurred in one case due to TALV lead fracture. CONCLUSIONS: This is the first study reporting the long-term outcome, mortality, and thromboembolic event rate exclusively after TALV lead implantation. Patients who underwent TALV lead implantation have a comparable long-term mortality rate to conventional CRT, although a major ischemic cerebrovascular event after TALV lead implantation is worrisome and has an impact on the outcome.

Two-Year Follow-Up after Contact Force Sensing Radiofrequency Catheter and Second-Generation Cryoballoon Ablation for Paroxysmal Atrial Fibrillation: A Comparative Single Centre Study.

Background. There are little comparative data on catheter ablation of paroxysmal atrial fibrillation (AF) using the contact force radiofrequency (CF-RF) catheter versus the second-generation cryoballoon (CB2). Methods and results. This is a single center, retrospective, nonrandomized study of 98 patients with symptomatic, drug-refractory paroxysmal AF who underwent their first PVI ablation using either the CB2 (n = 40) or CF-RF (n = 58). The mean age was 60 years with 63% men, a mean LA size of 42 mm. The procedure duration (74 ± 17 versus 120 ± 49 minutes p < 0.05) was shorter for CB2 group; the fluoroscopy time (14 ± 17 versus 16 ± 5 minutes, p = 0.45) was similar. Complete PVI was achieved in 96% of patients with RF-CF and 98% with CB2. Phrenic nerve palsies (2 transient and 1 persistent) occurred exclusively in the CB2 group and 1 severe, nonlethal complication (pericardial tamponade) occurred in the CF-RF group. At 24-month follow-up, the success rate, defined as freedom from AF/atrial tachycardia (AT) after a single procedure without antiarrhythmic drug, was comparable in CF-RF group and CB2 group (65.5% versus 67%, resp., log rank p = 0.54). Conclusion. Both the CB2 and the RF-CF ablation appeared safe; the success rate at 2 years was comparable between both technologies.

[Catheter ablation for paroxysmal atrial fibrillation: new generation cryoballoon or contact force sensing radiofrequency ablation?]. / A paroxysmalis pitvarfibrilláció kezelésének transzkatéteres ablatiós technikái: új generációs krioballon vagy kontaktero-méréssel kombinált rádiófrekvenciás ablatio?

INTRODUCTION: Contact force sensing radiofrequency ablation and the new generation cryoballoon ablation are prevalent techniques for the treatment of paroxysmal atrial fibrillation. AIM: The authors aimed to compare the procedural and 1-year outcome of patients after radiofrequency and cryoballoon ablation. METHOD: 96 patients with paroxysmal atrial fibrillation (radiofrequency ablation: 58, cryoballoon: 38 patients; 65 men and 31 women aged 28-70 years) were enrolled. At postprocedural 1, 3, 6 and 12 months ECG, Holter monitoring and telephone interviews were performed. RESULTS: Procedure and fluorosocopy time were: radiofrequency ablation, 118.5 ± 15 min and 15.8 ± 6 min; cryoballoon, 73.5 ± 16 min (p<0.05) and 13.8 ± 4.,1 min (p = 0.09), respectively. One year later freedom from atrial fibrillation was achieved in 76.5% of patients who underwent radiofrequency ablation and in 81% of patients treated with cryoballoon. Temporary phrenic nerve palsy occurred in two patients and pericardial tamponade developed in one patient. CONCLUSIONS: In this single center study freedom from paroxysmal atrial fibrillation was similar in the two groups with significant shorter procedure time in the cryoballoon group.

Could successful cryoballoon ablation of paroxysmal atrial fibrillation prevent progressive left atrial remodeling?

BACKGROUND: Radiofrequency catheter ablation of atrial fibrillation (AF) has been proved to be effective and to prevent progressive left atrial (LA) remodeling. Cryoballoon catheter ablation (CCA), using a different energy source, was developed to simplify the ablation procedure. Our hypothesis was that successful CCA can also prevent progressive LA remodeling. METHODS: 36 patients selected for their first CCA because of nonvalvular paroxysmal AF had echocardiography before and 3, 6 and 12 months after CCA. LA diameters, volumes (LAV) and LA volume index (LAVI) were evaluated. LA function was assessed by: early diastolic velocities of the mitral annulus (Aa(sept), Aa(lat)), LA filling fraction (LAFF), LA emptying fraction (LAEF) and the systolic fraction of pulmonary venous flow (PVSF). Detailed left ventricular diastolic function assessment was also performed. RESULTS: Excluding recurrences in the first 3-month blanking period, the clinical success rate was 64%. During one-year of follow-up, recurrent atrial arrhythmia was found in 21 patients (58%). In the recurrent group at 12 months after ablation, minimal LAV (38 ± 19 to 44 ± 20 ml; p < 0.05), maximal LAV (73 ± 23 to 81 ± 24 ml; p < 0.05), LAVI (35 ± 10 to 39 ± 11 ml/m2; p = 0.01) and the maximal LA longitudinal diameter (55 ± 5 to 59 ± 6 mm; p < 0.01) had all increased. PVSF (58 ± 9 to 50 ± 10%; p = 0.01) and LAFF (36 ± 7 to 33 ± 8%; p = 0.03) had decreased. In contrast, after successful cryoballoon ablation LA size had not increased and LA function had not declined. In the recurrent group LAEF was significantly lower at baseline and at follow-up visits. CONCLUSIONS: In patients whose paroxysmal atrial fibrillation recurred within one year after cryoballoon catheter ablation left atrial size had increased and left atrial function had declined. In contrast, successful cryoballoon catheter ablation prevented progressive left atrial remodeling.

A novel approach for endocardial resynchronization therapy: initial experience with transapical implantation of the left ventricular lead.

BACKGROUND: Coronary sinus lead placement for transvenous left ventricular (LV) pacing in cardiac resynchronization therapy (CRT) has a significant failure rate at implant and a considerable dislocation rate during follow-up. For these patients epicardial pacing lead implantation is the most frequently used alternative. Recent data support endocardial lead implantation through the atrial septum and the mitral valve, because this method provides further hemodynamic advantages. On the other hand transseptal CRT carries a significant risk for device related infective endocarditis of the mitral valve. The aim of this prospective, nonrandomized study was to demonstrate the feasibility of a fundamentally new approach for endocardial LV lead implantation. METHODS: We performed 12 transapical LV lead implantations in 10 end-stage heart failure patients. In each operation an active fixation lead was placed into the LV cavity using standard Seldinger technique through the LV apex. By use of a J-shaped guide wire, the tip of the lead was positioned and fixed into the basal-lateral segment of the LV under fluoroscopy guidance. Pacing parameters were assessed and found to be optimal in all patients. The lead was conducted through the chest wall near the apex into a subcutaneous tunnel up to the pocket of the previously implanted device. After surgery the patients are anticoagulated with target anticoagulation level identical to mechanical valve prostheses. RESULTS: In 8 patients there were no major or minor complications related to this new technique. During the follow-up period (mean 7.2 +/- 4.1 months) all patients responded favorably to the treatment. One lead dislocation and 1 pocket infection were detected; the lead repositioning and replacing could be performed without reopening of the pleural cavity. CONCLUSIONS: The potential advantages of this new technique are that it is minimally invasive, endocardial, and does not involve the mitral valve. LV lead repositioning can also be performed minimally invasively.

Alternative method for cardiac resynchronization: transapical lead implantation.

Alternative methods are necessary for cardiac resynchronization therapy when coronary sinus lead implantation fails. We aim to describe a fundamentally new approach using transapical implantation of an active fixation endocardial pacing lead. This technique is based on direct puncture of the left ventricular apex using the standard Seldinger technique. The tip of the lead is positioned with intracavital navigation under fluoroscopy. This method offers advantages for cardiac resynchronization because it is minimally invasive, provides endocardial pacing, and does not involve the mitral valve.

[New method for the treatment of atrial fibrillation: circumferential cryoballoon ablation of the pulmonary vein]. / A paroxizmális pitvarfibrilláció kezelésének új módszere: cryoballonos pulmonalis véna cirkumferenciális ablatiója.

Atrial fibrillation is the most frequent arrhythmia with increasing prevalence. Given a limited success rate of drug therapy for atrial fibrillation, interventional treatment options have been developed during the last years. Catheter ablation of atrial fibrillation (until recently the mostly used energy source was radiofrequency energy) has been established as an important therapeutic alternative. Depending on interpersonal (both on patient and operator side) and technical variabilities using radiofrequency energy potentially life-threatening complications such as pulmonary vein stenosis or atrio-esophageal fistulas may occur. Cryoenergy is a novel energy source for transcatheter ablation eliminating the arrhythmia substrate by freezing. The cornerstone of catheter ablation for atrial fibrillation is electrical isolation of the pulmonary veins. During cryoballoon ablation the targeted pulmonary vein transiently occluded by the inflated balloon catheter and using this method a circumferential lesion is created. The success rate of cryoballoon ablation is comparable with the radiofrequency ablation with increased safety. We performed the first cryoballoon ablations for patients with paroxysmal atrial fibrillation in Hungary. On this occasion we review the potential advantages of this technique which may serve as basis for its widespread use in the future.

Ice mapping during tachycardia in close proximity to the AV node is safe and offers advantages for transcatheter ablation procedures.

BACKGROUND: Ablation during ongoing orthodromic reentry tachycardia (AVRT) and atrioventricular nodal reentry tachycardia (AVNRT) is not recommended using radiofrequency energy when the arrhythmia substrate is located in close proximity to the atrioventricular (AV) node due to a significant risk for inadvertent AV block. The aim of the study is to test the feasibility of ice mapping during tachycardias involving arrhythmia substrate located in close proximity to the AV node. METHODS: This was a single-centre, prospective, randomized study. A total of 65 patients was screened and 30 patients with supraventricular arrhythmias were assigned either to a cryo or RF energy group after diagnosis of AVNRT (17 pts) or AVRT (13 pts) with an anteroseptal accessory pathway. RF ablation was performed using standard ablation techniques. In the cryo group, ice mapping was performed during tachycardia with cooling of the catheter tip temperature to a maximum of -40 degrees C. Ablation was performed only if ice mapping terminated the tachycardia without prolongation of the AV conduction. RESULTS: The overall acute success rate was 84%, and was not different in the cryo and RF groups (85% vs. 82.4%, P = 0.43). Both fluoroscopy and the procedure times were comparable. There was a marked reduction in the mean number of applications in the cryo group [2 (1-6) vs. 7 (1-41), P = 0.002]. In one patient ablation was not attempted in the cryo group because of AV prolongation, and in two patients temporary second-degree AV block was observed in the RF group. After 12 months follow-up the long-term success rate was similar between the two groups. CONCLUSIONS: (I) Ice mapping is a feasible method to determine the exact location of accessory pathways and of the slow pathway during tachycardia. (2) Ice mapping performed during tachycardia causes less ablation lesions without increasing the procedure and fluoroscopy times.

Unusual Wenckebach phenomenon due to an atrial tachycardia arising from the apex of Koch's triangle in the presence of dual AV nodal physiology.

A case of a patient with narrow QRS tachycardia and without structural heart disease is presented. The electrophysiologic study revealed an atrial tachycardia in the presence of dual atrioventricular (AV) nodal physiology and AV block at suprahisian level, the latter two leading to an unusual Wenckebach periodicity. The entire septal area was mapped as was the coronary sinus (CS) os and the earliest atrial activation was found at the apex of Koch's triangle in close vicinity to the His bundle (HB). Cryomapping at that point reproducibly terminated the tachycardia without impairing AV conduction. Cryoablation rendered the tachycardia non-inducible. Discontinuous AV conduction persisted but AV nodal reentrant tachycardia (AVNRT) was not inducible. Six months later the patient is arrhythmia-free.

[Catheter ablation for supraventricular tachycardia in children and congenital heart diseases]. / Supraventricularis tachycardiák katéterablatiója gyermekkorban és congenitalis szívhibákban.

INTRODUCTION: Recently catheter ablation has been accepted as standard therapy for symptomatic supraventricular tachycardia in children. Nature of childhood and the variability of congenital heart diseases and congenital heart surgery distinguishes pediatric catheter ablation from the adult practice. OBJECTIVES: The aim of the present study was to summarize a single-center experience of the first 30 consecutive patients regarding the electrophysiological studies and catheter ablations, moreover to report on the national adoption of these interventions for pediatric patients in Hungary. METHODS: Between April 1996 and September 2004 catheter ablation was offered for 30 children as treatment of their supraventricular tachycardia because of failure of pharmacological therapy or parents preference. RESULTS: The mean age of the patients was 13.7 years (2.3-18.0 years) and the mean weight was 52.0 kg (12.0-81 kg). Electrophysiology study revealed 33 arrhythmogenic substrates in 30 patients, 30 of those 33 were congenital while 3 were acquired. Catheter ablation was attempted in 27 patients with acute success in 24 cases (89%). Recurrence was observed in 2 patients and the redo ablation was effective in both, although a second recurrence occurred later in one of them. There were no major complications, but two minor ones (pseudoaneurysm of arteria femoralis, transient ventricular ectopy) occurred. CONCLUSIONS: Catheter ablation is safe and effective in children with congenital heart disease. Our results are comparable with the international data.