Faster, safer and better catheter ablation?

Undoubtedly the pace at which we are living increases step by step on a daily basis. Since this is a gradual process in general, this may go unnoticed to some, but the implications on healthcare are not to be taken too lightly. Interventional electrophysiology as a distinct entity is a relatively young discipline. It has gone through several groundbreaking changes in a short time span. Although the first measurements of cellular currents date from the late 1800s, in general the birth of invasive clinical electrophysiology, associated with the use of programmed electrical cardiac stimulation combined with intracardiac activation mapping by the groups of Durrer and Coumel, is said to be no earlier than 1967. After having been used for several years as a diagnostic tool to evaluate the effect of anti-arrhythmic drugs, the therapeutic options of electrophysiology emerged in the early 1980s with the ‘shock’ ablation of the His bundle. At roughly the same time the pacing branch of electrophysiology experienced a comparable ‘shock’ with the introduction of the first implantable automatic defibrillator. In the last decade, there has been a relentless innovation in the field of electrophysiology. The invasive electrophysiological armamentarium now consists of numerous diagnostic tools, multiple implantable devices aiming to pace, defibrillate or resynchronize the heart and a continuously growing number of manually and remotely navigated ablation catheters in various shapes and sizes

The magnetic navigation system allows safety and high efficacy for ablation of arrhythmias

Aims: We aimed to evaluate the safety and long-term efficacy of the magnetic navigation system (MNS) in a large number of patients. The MNS has the potential for improving safety and efficacy based on atraumatic catheter design and superior navigation capabilities. Methods and results: In this study, 610 consecutive patients underwent ablation. Patients were divided into two age- and sex-matched groups. Ablations were performed either using MNS (group MNS, 292) or conventional manual ablation [group manual navigation (MAN), 318]. The following parameters were analysed: acute success rate, fluoroscopy time, procedure time, complications [major: pericardial tamponade, permanent atrioventricular (AV) block, major bleeding, and death; minor: minor bleeding and temporary AV block]. Recurrence rate was assessed during follow-up (15 ± 9.5 months). Subgroup analysis was performed for the following groups: atrial fibrillation, isthmus dependent and atypical atrial flutter, atrial tachycardia, AV nodal re-entrant tachycardia, circus movement tachycardia, and ventricular tachycardia (VT). Magnetic navigation system was associated with less major complications (0.34 vs. 3.2%, P = 0.01). The total numbers of complications were lower in group MNS (4.5 vs. 10%, P = 0.005). Magnetic navigation system was equally effective as MAN in acute success rate for overall groups (92 vs. 94%, P = ns). Magnetic navigation system was more successful for VTs (93 vs. 72%, P < 0.05). Less fluoroscopy was used in group MNS (30 ± 20 vs. 35 ± 25 min, P < 0.01). There were no differences in procedure times and recurrence rates for the overall groups (168 ± 67 vs. 159 ± 75 min, P = ns; 14 vs. 11%, P = ns; respectively). Conclusions: Our data suggest that the use of MNS improves safety without compromising efficiency of ablations. Magnetic navigation system is more effective than manual ablation for VTs. Published on behalf of the European Society of Cardiology. All rights reserved

Robotic magnetic navigation-guided catheter ablation establishes highly effective pulmonary vein isolation in patients with paroxysmal atrial fibrillation when compared to conventional ablation techniques

Introduction: Pulmonary vein isolation (PVI) is a pivotal part of ablative therapy for atrial fibrillation (AF). Currently, there are multiple techniques available to realize PVI, including: manual-guided cryoballoon (MAN-CB), manual-guided radiofrequency (MAN-RF), and robotic magnetic navigation-guided radiofrequency ablation (RMN-RF). There is a lack of large prospective trials comparing contemporary RMN-RF with the more conventional ablation techniques. This study prospectively compared three catheter ablation techniques as treatment of paroxysmal AF. Methods: This multicenter, prospective study included patients with paroxysmal AF who underwent their first ablation procedure. Procedural parameters (including procedural efficiency), complication rates, and freedom of AF during 12-month follow-up, were compared between three study groups which were defined by the utilized ablation technique. Results: A total of 221 patients were included in this study. Total procedure time was significantly shorter in MAN-CB (78 ± 21 min) compared to MAN-RF (115 ± 41 min; p &lt;.001) and compared to RMN-RF (129 ± 32 min; p &lt;.001), whereas it was comparable between the two radiofrequency (RF) groups (p =.062). A 3% complication rate was observed, which was comparable between all groups. At 12-month follow-up, AF recurrence was observed in 40 patients (19%) and was significantly lower in the robotic group (MAN-CB 19 [24%], MAN-RF 16 [23%], RMN-RF 5 [8%] AF recurrences, p =.045) (multivariate hazard ratio of RMN-RF on AF recurrence 0.32, 95% confidence interval: 0.12–0.87, p =.026). Conclusion: RMN-guided PVI results in high freedom of AF in patients with paroxysmal AF, when compared to cryoablation and manual RF ablation. Cryoablation remains the most time-efficient ablation technique, whereas RMN nowadays has comparable efficiency with manual RF ablation.</p

Cardiac troponin I release after transcatheter closure of the interatrial septum: a prospective study

Objective -To identify cTnI rise after percutaneous ISD closure and to determine its prognostic significance. Background - Cardiac troponin-I (cTnI) is a very specific and sensitive marker of myocardial injury.A significant increase of cTnI levels after percutaneous interatrial septal defect (ISD) closure has been reported.status: publishe

Effect of magnetic navigation system on procedure times and radiation risk in children undergoing catheter ablation

Transcatheter ablation is an effective method to eliminate the arrhythmogenic substrate in symptomatic children with various types of arrhythmias. A reduction in the procedure and fluoroscopy time would decrease the hazardous effects of the ablation procedures. The magnetic navigation system (MNS) uses atraumatic catheters and facilitates accurate catheter placement in all regions of the heart for mapping and therapy delivery. We compared the efficacy and safety between a manual and MNS-guided approach for mapping and ablation of arrhythmias in a general pediatric arrhythmia population and in a subgroup of young children aged <10 years old. A total of 58 pediatric patients (mean age 12.2 +/- 3.2 years) were included in the present study. Of the 58 consecutive patients, 29 were treated with the MNS and 29 underwent conventional manual ablation. No demographic differences were present between the 2 groups. Acute success was achieved in 26 of 29 patients and 27 of 29 patients (p = NS). The mean procedure and fluoroscopy times were comparable in both study groups (168 +/- 56 minutes vs 183 +/- 52 minutes, p = NS; and 22 +/- 59 minutes vs 30 +/- 29 minutes, p = NS). In young children (aged <10 years), the success rate did not differ between the 2 groups (10 of 11 vs 6 of 8, p = NS). However, significant decreases in the procedure and fluoroscopy times were achieved (139 +/- 57 minutes vs 204 +/- 49 minutes and 13 +/- 7 minutes vs 31 +/- 28 minutes, respectively; p = 0.01 and p = 0.04). In conclusion, our data have strongly suggested that using the MNS for treating young children is advantageous, because it significantly reduced the procedure and fluoroscopy times without compromising efficacy. (C) 2010 Elsevier Inc. All rights reserved. (Am J Cardiol 2010;106:69-72

The presence of extensive atrial scars hinders the differential diagnosis of focal or macroreentrant atrial tachycardias in patients with complex congenital heart disease

Atrial tachycardias (ATs) frequently develop in patients with congenital heart defects (CHDs). This study aimed to evaluate the effects of extensive atrial scar formation on the total atrial activation time (TAAT) and its relation to the tachycardia cycle length (CL) to classify AT. Seventy-one patients were included and divided into two groups: patients without CHD (Group I, 35 patients) and with CHD (Group II, 36 patients). All patients underwent CARTO electroanatomical activation mapping. Two subgroups were created: centrifugal (CAT) or macroreentrant AT (MRAT). Total atrial activation time, CL, and mean bipolar signal amplitude (BiSA) were analysed. In Group I, 18 patients (51.4%) had CAT and 17 (48.6%) MRAT. The mean BiSA for Group I was 1.30 +/- 0.32 mV. Total atrial activation time/CL ratios were different between CAT and MRAT (28.4 +/- 16.9 vs. 66.6 +/- 14.3%, P &lt; 0.001). In Group II, 18 patients (50%) had CAT and 18 patients (50%) MRAT. The mean BiSA was 0.94 +/- 0.50 mV and was not different for CAT and MRAT subgroups (1.04 +/- 0.64 vs. 0.85 +/- 0.29, P = 0.243). Total atrial activation time/CL ratios were comparable between CAT and MRAT patients (69.0 +/- 40.4 vs. 83.6 +/- 8.3%, P = 0.243). A significant lower BiSA was found for CAT with TAAT/CL ratios above 40% (0.62 +/- 0.11 vs. 1.90 +/- 0.18 mV, P &lt; 0.001). A strong negative correlation was identified between the BiSA and the TAAT/CL ratio in patients with CAT in Group II (-0.742; P &lt; 0.001). Low mean BiSA values in CHD patients are associated with altered impulse propagation, making TAAT- and CL-based diagnostic tools inaccurate. Further diagnostic tests are needed to determine the correct mechanism of ATs

Initial experience with catheter ablation using remote magnetic navigation in adults with complex congenital heart disease and in small children

Background: The improved outcomes and increased availability of surgery for congenital heart disease (CHD) over the last three decodes have created a small but steadily increasing subset of patients with unique needs: children and adults with complex arrhythmias in the setting of structural cardiac abnormalities, Radiofrequency catheter ablation (RFCA) in these patients, and in small children with normal cardiac anatomy, is effective but challenging. An understanding of specific anatomical and electrophysiological characteristics of these patients and the technical challenges in addressing them are critical to the success of this therapy. Tools specifically designed for intracardiac diagnosis and therapy in anatomically complex and/or small hearts remain scarce. Aims: We report single-center results from an ongoing registry of all patients with congenital heart disease and all children with complex arrhythmias in which the Magnetic Navigation System (MNS) was used. Results: Included in this report are 12 patients with CHD in whom 17 tachyarrhythmias were treated, and 11 pediatric patients with normal cardiac anatomy who each had a single arrhythmia. The procedures' duration and the duration of fluoroscopy time as well as arrhythmia recurrence rates were comparable to those found in previous reports of procedures performed in adults with structurally normal hearts, and the incidence of complications was quite low. Discussion: In patients with complex congenital malformations, retrograde mapping of the pulmonary venous atrium was feasible, eliminating the need for puncture of the atrial septum, or surgically placed baffle in many cases. Moreover, the design of the catheter eliminated the need for multiple mapping and ablation catheters. Conclusion: Our findings suggest that RFCA using the MNS for arrhythmias after surgery for congenital heart disease and in pediatric patients is safe and effective