Intracardiac echocardiography-guided transseptal puncture for fluoroless catheter ablation of left-sided tachycardias

Initial experience with zero-fluoroscopy pulmonary vein isolation in patients with atrial fibrillation: single-center observational trial

Pulmonary vein isolation (PVI) stands as a widely practiced cardiac ablation procedure on a global scale, conventionally guided by fluoroscopy. The concurrent application of electroanatomical mapping systems (EAMS) and intracardiac echocardiography offers a means to curtail radiation exposure. This study aimed to compare procedural outcomes between conventional and our initial zero-fluoroscopy cases in patients with paroxysmal or persistent atrial fibrillation (AF), undergoing point-by-point PVI. Our prospective observational study included 100 consecutive patients with AF who underwent point-by-point radiofrequency PVI. The standard technique was used in the first 50 cases (Standard group), while the fluoroless technique was used in the subsequent 50 patients (Zero group). The zero-fluoroscopy approach exhibited significantly shorter procedural time (59.6 ± 10.7 min vs. 74.6 ± 13.2 min, p < 0.0001), attributed to a reduced access time (17 [16; 20] min vs. 31 [23; 34.5] min, p < 0.001). Comparable results were found for the number of RF applications, total ablation energy, and left atrial dwelling time. In the Zero group, all procedures were achieved without fluoroscopy, resulting in significantly lower fluoroscopy time (0 [0; 0] sec vs. 132 [100; 160] sec, p < 0.0001) and dose (0 [0; 0] mGy vs. 4.8 [4.1; 8.2] mGy, p < 0.0001). The acute success rate was 100%, with no major complications. Zero-fluoroscopy PVI is feasible, safe, and associated with shorter procedure times compared to the standard approach, even in cases without prior experience in zero-fluoroscopy PVI.

Intracardiac echocardiography in paediatric and congenital cardiac ablation shortens procedure duration and improves success without complications

AIMS

Common to adult electrophysiology studies (EPSs), intracardiac echocardiography (ICE) use in paediatric and congenital heart disease (CHD) EPS is limited. The purpose of this study was to assess the efficacy of ICE use and incidence of associated complications in paediatric and CHD EPS.

METHODS AND RESULTS

This single-centre retrospective matched cohort study reviewed EPS between 2013 and 2022. Demographics, CHD type, and EPS data were collected. Intracardiac echocardiography cases were matched 1:1 to no ICE controls to assess differences in complications, ablation success, fluoroscopy exposure, procedure duration, and arrhythmia recurrence. Cases and controls with preceding EPS within 5 years were excluded. Intracardiac echocardiography cases without an appropriate match were excluded from comparative analyses but included in the descriptive cohort. We performed univariable and multivariable logistic regression to assess associations between variables and outcomes. A total of 335 EPS were reviewed, with ICE used in 196. The median age of ICE cases was 15 [interquartile range (IQR) 12-17; range 3-47] years, and median weight 57 [IQR 45-71; range 15-134] kg. There were no ICE-related acute or post-procedural complications. There were 139 ICE cases matched to no ICE controls. Baseline demographics and anthropometrics were similar between cases and controls. Fluoroscopy exposure (P = 0.02), procedure duration (P = 0.01), and arrhythmia recurrence (P = 0.01) were significantly lower in ICE cases.

CONCLUSION

Intracardiac echocardiography in paediatric and CHD ablations is safe and reduces procedure duration, fluoroscopy exposure, and arrhythmia recurrence. However, not every arrhythmia substrate requires ICE use. Thoughtful selection will ensure the judicious and strategic application of ICE to enhance outcomes.

The Fluoroless Future in Electrophysiology: A State-of-the-Art Review

Fluoroscopy has always been the cornerstone imaging method of interventional cardiology procedures. However, radiation exposure is linked to an increased risk of malignancies and multiorgan diseases. The medical team is even more exposed to X-rays, and a higher incidence of malignancies was reported in this professional group. In the last years, X-ray exposure has increased rapidly, involving, above all, the medical team and young patients and forcing alternative fluoroless imaging methods. In cardiac electrophysiology (EP) and pacing, the advent of 3D electroanatomic mapping systems with dedicated catheters has allowed real-time, high-density reconstruction of both heart anatomy and electrical activity, significantly reducing the use of fluoroscopy. In addition, the diffusion of intracardiac echocardiography has provided high anatomical resolution of moving cardiac structures, providing intraprocedural guidance for more complex catheter ablation procedures. These methods have largely demonstrated safety and effectiveness, allowing for a dramatic reduction in X-ray delivery in most arrhythmias' ablations. However, some technical concerns, as well as higher costs, currently do not allow their spread out in EP labs and limit their use to only procedures that are considered highly complex and time-consuming and in young patients. In this review, we aim to update the current employment of fluoroless imaging in different EP procedures, focusing on its strengths and weaknesses.

Zero-fluoroscopy ablation with multielectrode pulse field ablation system: Case series

Pulse field ablation (PFA) is a novel nonthermal ablation modality for treatment of atrial fibrillation. While mostly lacking 3D electroanatomical mapping integration, reported radiation doses in procedures using multielectrode PFA catheters are relatively high. We report a first case series of three patients where a zero-fluoroscopy approach by intracardiac echocardiography was utilized and present a possible workflow for zero-fluoroscopy ablation with the Farapulse PFA system.

Intracardiac echocardiography is a promising strategy for guiding closure of the left atrial appendage

Background and Aims

Percutaneous transcatheter left atrial appendage (LAA) closure (LAAC) is an effective approach for preventing ischemic stroke in nonvalvular atrial fibrillation patients. Intracardiac echocardiography (ICE), a new imaging modality, is a promising strategy for guiding LAAC. This review highlights the various strategies for ICE-guided-LAAC as an option for clinical policy.

Methods

A comprehensive literature search was conducted of PubMed, ScienceDirect, Ovid Web of Science, SpringerLink, and other notable databases to identify recent peer-reviewed clinical trials, reviews, and research articles related to ICE and its application in the guidance of LAAC.

Results

Various methods are used to evaluate the spatial structure and dimensions of the LAA. The main techniques for guiding LAAC are transesophageal echocardiography (TEE), cardiac computed tomography (CTA), and ICE. Among these techniques, the advantages of ICE typically include (1) multiangle and real-time assessment of intracardiac structure, (2) a reduction in procedural fluoroscopy, (3) reduced operation time and improved workflow in the catheterization laboratory, and (4) the avoidance of general anesthesia and the early detection of complications.

Conclusion

ICE is a promising strategy for the guidance of LAAC. Among the most advanced and recent technological innovations in cardiovascular imaging in general and volume imaging in particular, ICE offers greater efficacy and safety.

Feasibility and safety of reprocessing of intracardiac echocardiography catheters for electrophysiology procedures - a large single center experience

PURPOSE

Intra-cardiac echocardiography (ICE) has become an important tool for catheter ablation. Adoption of ICE imaging is still limited because of its prohibitively high cost. Our aim was to study the safety and feasibility of ICE catheters reprocessing and its environmental and financial impact.

METHODS

This was a single center retrospective analysis of all consecutive electrophysiology procedures in which ICE catheters were used from 2015 to 2022. In total, 1128 patients were studied (70.6% male, mean age was 57.9 ± 13.2 years). The majority of procedures were related to atrial fibrillation ablation (84.6%).

RESULTS

For the whole cohort, 57 new ICE catheters were used. Consequently one catheter could be used for 19.8 procedures. New catheters were only used when the image obtained by reused probes was not satisfactory. There were no cases of ICE probe steering mechanism malfunction, no procedure related infections and no allergic reactions that could be attributed to the resterilization process. In total, there was 8.6% of complications not related to ICE imaging. Financially, ICE probe reprocessing resulted with 90% cost reduction (> 2 millions of Euros savings for the studied period) and 95% waste reduction (639.5 kg less, mostly non degradable waste was produced).

CONCLUSION

Our data suggests that ICE catheter reprocessing is feasible and safe. It seems that risk of infection is not increased. Significant economic and environmental savings could be achieved by ICE catheters reprocessing. Furthermore, ICE reprocessing could allow more extensive ICE usage resulting in safer procedures with a potential reduction of serious complications.

Zero-Fluoroscopy Catheter Ablation of Supraventricular Tachycardias in the Pediatric Population

Catheter ablation (CA) of supraventricular tachycardias (SVTs) is conventionally performed with the aid of X-ray fluoroscopy. Usage of a three-dimensional (3D) electro-anatomical mapping (EAM) system and intracardiac echocardiography (ICE) enables zero-fluoroscopy ablation, eliminating the harmful effects of radiation. We retrospectively analyzed the feasibility, effectiveness and safety of zero-fluoroscopy radiofrequency and cryoablation of various types of SVTs in pediatric patients. Overall, in 171 consecutive patients (12.5 ± 3.9 years), 175 SVTs were diagnosed and 201 procedures were performed. The procedural success rate was 98% (193/197), or more precisely, 100% (86/86) for AVNRT, 95.8% (91/95) for AVRT, 94.1% (16/17) for AT and 100% (2/2) for AFL. No complications were recorded. Follow-up was complete in 100% (171/171) of patients. During the mean follow-up period of 488.4 ± 409.5 days, 98.2% of patients were arrhythmia-free with long-term success rates of 98.7% (78/79), 97.5% (78/80), 100% (13/13) and 100% (2/2) for AVNRT, AVRT, AT and AFL, respectively. Zero-fluoroscopy CA of various types of SVTs in the pediatric population is a feasible, effective and safe treatment option.

Use of a new non-contrast-enhanced BOOST cardiac MR sequence before electrical cardioversion or ablation of atrial fibrillation-a pilot study

Introduction

Left atrial appendage (LAA) thrombus is the most common source of embolization in atrial fibrillation (AF). Transesophageal echocardiography (TEE) is the gold standard method for LAA thrombus exclusion. Our pilot study aimed to compare the efficacy of a new non-contrast-enhanced cardiac magnetic resonance (CMR) sequence (BOOST) with TEE for the detection of LAA thrombus and to evaluate the usefulness of BOOST images for planning radiofrequency catheter ablation (RFCA) compared with left atrial (LA) contrast-enhanced computed tomography (CT). We also attempted to assess the patients' subjective experiences with TEE and CMR.

Methods

Patients with AF undergoing either electrical cardioversion or RFCA were enrolled. Participants underwent pre-procedural TEE and CMR scans to evaluate LAA thrombus status and pulmonary vein anatomy. Patient experiences with TEE and CMR were assessed using a questionnaire developed by our team. Some patients scheduled for RFCA also had pre-procedural LA contrast-enhanced CT. In such cases, the operating physician was asked to subjectively define the quality of the CT and CMR scan on a scale of 1-10 (1 = worst, 10 = best) and comment on CMR's usefulness in RFCA planning.

Results

Seventy-one patients were enrolled. In 94.4%, both TEE and CMR excluded, and in 1 patient, both modalities reported the presence of LAA thrombus. In 1 patient, TEE was inconclusive, but CMR excluded LAA thrombus. In 2 patients, CMR could not exclude the presence of thrombus, but in 1 of those cases, TEE was also indecisive. During TEE, 67%, during CMR, only 1.9% of patients reported pain (p < 0.0001), and 89% would prefer CMR in case of a repeat examination. The quality of the left atrial contrast-enhanced CT scans was better compared with the image quality of the CMR BOOST sequence [8 (7-9) vs. 6 (5-7), p < 0.0001]. Still, the CMR images were useful for procedural planning in 91% of cases.

Conclusion

The new CMR BOOST sequence provides appropriate image quality for ablation planning. The sequence might be useful for excluding larger LAA thrombi; however, its accuracy in detecting smaller thrombi is limited. Most patients preferred CMR over TEE in this indication.

Zero fluoroscopy catheter ablation for atrial fibrillation: a systematic review and meta-analysis

Introduction

Catheter ablation for atrial fibrillation (AF) is the most frequently performed cardiac ablation procedure worldwide. The majority of ablations can now be performed safely with minimal radiation exposure or even without the use of fluoroscopy, thanks to advances in 3-dimensional electroanatomical mapping systems and/or intracardiac echocardiography. The aim of this study was to conduct a meta-analysis to compare the effectiveness of zero fluoroscopy (ZF) versus non-zero fluoroscopy (NZF) strategies for AF ablation procedures.

Methods

Electronic databases were searched and systematically reviewed for studies comparing procedural parameters and outcomes of ZF vs. NZF approaches in patients undergoing catheter ablation for AF. We used a random-effects model to derive the mean difference (MD) and risk ratios (RR) with a 95% confidence interval (CI).

Results

Our meta-analysis included seven studies comprising 1,593 patients. The ZF approach was found to be feasible in 95.1% of patients. Compared to the NZF approach, the ZF approach significantly reduced procedure time [mean difference (MD): -9.11 min (95% CI: -12.93 to -5.30 min; p < 0.01)], fluoroscopy time [MD: -5.21 min (95% CI: -5.51 to -4.91 min; p < 0.01)], and fluoroscopy dose [MD: -3.96 mGy (95% CI: -4.27 to -3.64; p < 0.01)]. However, there was no significant difference between the two groups in terms of total ablation time [MD: -104.26 s (95% CI: -183.37 to -25.14; p = 0.12)]. Furthermore, there was no significant difference in the acute [risk ratio (RR): 1.01, 95% CI: 1.00-1.02; p = 0.72] and long-term success rates (RR: 0.96, 95% CI: 0.90-1.03; p = 0.56) between the ZF and NZF methods. The complication rate was 2.76% in the entire study population and did not differ between the groups (RR: 0.94, 95% CI: 0.41-2.15; p = 0.89).

Conclusion

The ZF approach is a feasible method for AF ablation procedures. It significantly reduces procedure time and radiation exposure without compromising the acute and long-term success rates or complication rates.

Best Practices for the Catheter Ablation of Ventricular Arrhythmias

Techniques for catheter ablation have evolved to effectively treat a range of ventricular arrhythmias. Pre-operative electrocardiographic and cardiac imaging data are very useful in understanding the arrhythmogenic substrate and can guide mapping and ablation. In this review, we focus on best practices for catheter ablation, with emphasis on tailoring ablation strategies, based on the presence or absence of structural heart disease, underlying clinical status, and hemodynamic stability of the ventricular arrhythmia. We discuss steps to make ablation safe and prevent complications, and techniques to improve the efficacy of ablation, including optimal use of electroanatomical mapping algorithms, energy delivery, intracardiac echocardiography, and selective use of mechanical circulatory support.

Understanding the scope of intracardiac echocardiography in catheter ablation of ventricular arrhythmia

Over the last few decades, catheter ablation has emerged as the first-line treatment for ventricular arrhythmias. However, detailed knowledge of cardiac anatomy during the surgery remains the prerequisite for successful ablation. Intracardiac echocardiography (ICE) is a unique imaging technique, which provides real-time visualization of cardiac structures, and is superior to other imaging modalities in terms of precise display of cardiac tissue characteristics as well as the orientation of anatomical landmarks. This article aimed to introduce the various advantages and limitations of ICE in the ablation of ventricular arrhythmias.

Intracardiac echocardiography Chinese expert consensus

In recent years, percutaneous catheter interventions have continuously evolved, becoming an essential strategy for interventional diagnosis and treatment of many structural heart diseases and arrhythmias. Along with the increasing complexity of cardiac interventions comes ever more complex demands for intraoperative imaging. Intracardiac echocardiography (ICE) is well-suited for these requirements with real-time imaging, real-time monitoring for intraoperative complications, and a well-tolerated procedure. As a result, ICE is increasingly used many types of cardiac interventions. Given the lack of relevant guidelines at home and abroad and to promote and standardize the clinical applications of ICE, the members of this panel extensively evaluated relevant research findings, and they developed this consensus document after discussions and correlation with front-line clinical work experience, aiming to provide guidance for clinicians and to further improve interventional cardiovascular diagnosis and treatment procedures.

Safety and efficacy of zero-fluoroscopy catheter ablation for paroxysmal supraventricular tachycardia in Chinese children

Objectives

To compare the safety and efficacy of completely zero-fluoroscopy radiofrequency ablation (RFA) with that of conventional RFA guided by three-dimensional mapping in Chinese children with paroxysmal supraventricular tachycardia (PSVT).

Methods

The study had a single-center observational design and included 46 children aged 6–14 years who underwent RFA for PSVT at the Second Hospital of Hebei Medical University between March 2019 and September 2021. The children were divided according to whether they underwent zero-fluoroscopy RFA (zero-fluoroscopy group, n = 26) or routine RFA under X-ray guidance (conventional group, n = 20). Three-dimensional mapping was used in both groups. Baseline characteristics, total procedure time, RFA time, volume and duration of X-ray exposure, target mapping time, the immediate RFA success rate, incidence of complications, and recurrence rate were compared between the two groups.

Results

The children had a median age of 12 years (interquartile range 10, 13), 47.8% (22/46) were boys, and 52.2% (24/46) were girls. The mean body weight was 48.75 ± 15.26 kg. There was no significant between-group difference in the baseline data (P > 0.05). All children were followed up as outpatients at 1, 3, and 6 months postoperatively. The target mapping time was significantly longer in the zero-fluoroscopy group than in the conventional group (12.96 ± 2.24 min vs. 6.65 ± 2.56 min, P < 0.05); however, there was no significant between-group difference in the immediate success rate (100% vs. 100%), success rate at 6 months postoperatively (92.30% vs. 95.00%), complication rate (0% vs. 0.05%), recurrence rate (7.70% vs. 5.00%), RFA time (212.50 s vs. 214.00 s), or total procedure time (78.50 min vs. 74.00 min) (P > 0.05).

Conclusion

Zero-fluoroscopy catheter ablation can completely avoid fluoroscopy exposure in children without affecting the safety and efficacy of RFA.

Can intracardiac echocardiography completely replace transesophageal echocardiography to guide left atrial appendage closure?-The comparisons of intracardiac echocardiography with transesophageal echocardiography

Left atrial appendage closure (LAAC) is an effective means of preventing ischemic stroke in patients with nonvalvular atrial fibrillation. Transesophageal echocardiography (TEE) is the primary imaging technique to guide LAAC. Its shortcomings, namely the use of general anesthesia and tracheal intubation, inevitably increase procedural risks. Intracardiac echocardiography (ICE), a novel imaging modality for guiding LAAC, has proven more advantageous over TEE due to use of local anesthesia, shortened procedural time, and reduced radiation exposure. This review highlights the differences between ICE and TEE guided LAAC, aiming to provide a reference for clinical decision-making.

Transseptal puncture for left atrial ablation: risk factors for cardiac tamponade and a proposed causative classification system

Aims

Cardiac tamponade is a high morbidity complication of transseptal puncture (TSP). We examined the associations of TSP‐related cardiac tamponade (TRCT) for all patients undergoing left atrial ablation at our center from 2016 to 2020.

Methods and Results

Patient and procedural variables were extracted retrospectively. Cases of cardiac tamponade were scrutinized to adjudicate TSP culpability. Adjusted multivariate analysis examined predictors of TRCT. A total of 3239 consecutive TSPs were performed; cardiac tamponade occurred in 51 patients (incidence: 1.6%) and was adjudicated as TSP‐related in 35 (incidence: 1.1%; 68.6% of all tamponades). Patients of above‐median age [odds ratio (OR): 2.4 (1.19–4.2), p = .006] and those undergoing re‐do procedures [OR: 1.95 (1.29–3.43, p = .042] were at higher risk of TRCT. Of the operator‐dependent variables, choice of transseptal needle (Endrys vs. Brockenbrough, p > .1) or puncture sheath (Swartz vs. Mullins vs. Agilis vs. Vizigo vs. Cryosheath, all p > .1) did not predict TRCT. Adjusting for operator, equipment and demographics, failure to cross the septum first pass increased TRCT risk [OR: 4.42 (2.45–8.2), p = .001], whilst top quartile operator experience [OR: 0.4 (0.17–0.85), p = .002], transoesophageal echocardiogram [TOE prevalence: 26%, OR: 0.51 (0.11–0.94), p = .023], and use of the SafeSept transseptal guidewire [OR: 0.22 (0.08–0.62), p = .001] reduced TRCT risk. An increase in transseptal guidewire use over time (2016: 15.6%, 2020: 60.2%) correlated with an annual reduction in TRCT (R² = 0.72, p < .001) and was associated with a relative risk reduction of 70%.

Conclusions

During left atrial ablation, the risk of TRCT was reduced by operator experience, TOE‐guidance, and use of a transseptal guidewire, and was increased by patient age, re‐do procedures, and failure to cross the septum first pass.

Conventional fluoroscopy-guided versus zero-fluoroscopy catheter ablation of supraventricular tachycardias

Purpose

The aim of this study was to evaluate the safety and efficacy of zero-fluoroscopy (ZF) catheter ablation (CA) for supraventricular tachycardias (SVT).

Methods

584 consecutive patients referred to our institution for CA of SVT were analysed. Patients were categorised into two groups; zero-fluoroscopy (ZF) group and conventional fluoroscopy (CF) group. The ZF group was further divided into two subgroups (adults and paediatric). Patient characteristics, procedural information, and follow-up data were compared.

Results

The ZF group had a higher proportion of paediatric patients (42.2% vs 0.0%; p < 0.001), resulting in a younger age (30.9 ± 20.3 years vs 52.7 ± 16.5 years; p < 0.001) and lower BMI (22.8 ± 5.7 kg/m2 vs 27.0 ± 5.4 kg/m2; p < 0.001). Procedure time was shorter in the ZF group (94.2 ± 50.4 min vs 104.0 ± 54.0 min; p = 0.002). There were no major complications and the rate of minor complications did not differ between groups (0.0% vs 0.4%; p = 0.304). Acute procedural success as well as the long-term success rate when only the index procedure was considered did not differ between groups (92.5% vs 95.4%; p = 0.155; 87.1% vs 89.2%; p = 0.422). When repeated procedures were included, the long-term success rate was higher in the ZF group (98.3% vs 93.5%; p = 0.004). The difference can be partially explained by the operators' preferences.

Conclusion

The safety and efficacy of ZF procedures in adult and paediatric populations are comparable to that of CF procedures.

The First Evaluation of Remote Magnetic Navigation-Guided Pediatric Ventricular Arrhythmia Ablation

Catheter ablation (CA) is an important treatment option for ventricular arrhythmias (VA) in pediatric cardiology. Currently, various CA techniques are available, including remote magnetic navigation (RMN)-guided radiofrequency (RF) ablation. However, no studies evaluate RMN-guided ablative therapy outcomes in children with VA yet. This study aimed to compare procedural and long-term outcomes between RMN-guided and manual (MAN)-guided VA ablation in children. This single-center, retrospective study included all CA procedures for VA performed in children with or without structural heart disease from 2008 until 2020. Two study groups were defined by CA technique: RMN or MAN. Primary outcome was recurrence of VA. Baseline clinical, procedural and safety data were also evaluated. This study included 22 patients, who underwent 30 procedures, with a median age of 15 (IQR 14-17; range 1-17) years and a mean weight of 57 ± 20 kg. In total, 14 procedures were performed using RMN and 16 using MAN (22 first and 8 redo procedures). Regarding first procedures, recurrence rates were significantly lower in RMN compared to MAN (20% versus 67%, P = 0.029), at a mean follow-up of 5.2 ± 3.0 years. Moreover, fluoroscopy dosages were significantly lower in RMN compared to MAN [20 (IQR 14-54) versus 48 (IQR 38-62) mGy, P = 0.043]. In total, 20 patients (91%) were free of VA following their final ablation procedure. This is the first study to investigate the use of RMN in pediatric VA ablation. RMN showed improved outcomes compared to MAN, resulting in lower VA recurrence and reduced fluoroscopy exposure.

Fluoroless Catheter Ablation of Atrial Fibrillation: Integration of Intracardiac Echocardiography and Cartosound Module

Objective

To evaluate the feasibility, safety, and clinical efficacy of non-fluoroscopic radiofrequency catheter ablation of atrial fibrillation (AF) in comparison to traditional fluoroscopy-guided ablation in a local Canadian community cohort.

Methods

We retrospectively studied consecutive patients with paroxysmal and persistent AF undergoing pulmonary vein isolation (PVI) guided by intracardiac echocardiography (ICE) and Carto system (CartoSound module). ICE-guided PVI without fluoroscopy (Zero-fluoro group) was performed in 116 patients, and conventional fluoroscopy-guided PVI (Traditional group) was performed in 131 patients.

Results

Two hundred and forty-seven patients with AF (60.7% male; mean age: 62.2 ± 10.6 years; paroxysmal AF =63.1%) who underwent PVI were studied. Mean procedure times were similar between both groups (136.8±33.4 minutes in the zero-fluoro group vs. 144.3±44.9 minutes in the traditional group; p=0.2). Acute PVI was achieved in all patients. Survival from early AF recurrence was 85% and 81% in the zero-fluoro and traditional groups, respectively (p = 0.06). Survival from late AF recurrence (12-months) between the zero-fluoro and traditional groups was also similar (p=0.1). Moreover, there were no significant differences between complication rates, including hematoma (p = 0.2) and tamponade (p = 1),between both groups.

Conclusions

Zero-fluoroscopy ICE and CartoSound-guided AF ablation may be safe and feasible in patients undergoing PVI compared to conventional fluoroscopy-guided ablation.

Zero-fluoroscopy ablation in patients with cardiac electronic implantable devices

INTRODUCTION

Utilizing a three-dimensional (3-D) mapping system and intracardiac echocardiography (ICE) has allowed ablation procedures with less or without fluoroscopy; however, there is limited data for patients with cardiac electronic implantable device (CIED) leads regarding the suspected risk of lead injury. Therefore, we sought to explore technics to perform safe trans-septal approach and catheter manipulation technique in patients with CIED leads.

METHODS AND RESULTS

This study comprised 49 consecutive patients (59% males, median 73 years old) with CIED who underwent catheter ablation for supraventricular tachycardia requiring the trans-septal approach, 15 without fluoroscopy (zero-fluoro group), and 34 with fluoroscopy (conventional-fluoro group), between July 2019 and April 2021. All procedures were performed under a 3-D mapping system and ICE guidance. We compared the differences in treatment and development of complications between the two groups. The procedures were for atrial fibrillation (82%) and atrial tachycardia (76%). Coronary sinus catheter insertion and the trans-septal procedure were successfully performed in all patients. The median time from venipuncture to trans-septal procedure (zero-fluoro vs. conventional-fluoro group: 28 [18-37] min vs. 24 [21-31] min, p = .70), total procedure time (231 [142-274] min vs. 175 [163-225] min, p = .63), and the acute procedural success rate (100% vs. 97%, p = 1.00) did not differ between both groups. No patient showed lead-related complications in both groups.

CONCLUSION

This is the first study to show zero-fluoro ablation for supraventricular arrhythmia using 3-D mapping and ICE in patients with CIED leads was feasible under careful catheter manipulation.

Fluoroscopy-free ablation in congenital heart disease of moderate or great complexity

BACKGROUND

Fluoroscopy-free (FF) ablation has been demonstrated to be safe and successful in patients with structurally normal hearts, but has not been systematically evaluated in patients with congenital heart disease (CHD) of moderate or great (M/G) complexity. This study aimed to evaluate and compare feasibility, safety, and outcomes of FF ablation in patients with or without M/G-CHD.

METHODS

Consecutive patients undergoing electrophysiologic study and intended catheter ablation over a 24-month period were included. Subgroups were created based on presence and complexity of CHD-M/G-CHD or simple complexity/no CHD (S/N-CHD). Cases with total radiation dose of zero qualified as FF. Demographic and peri-procedural variables and outcome data were analyzed.

RESULTS

A total of 89 procedures were included with 62 comprising the S/N-CHD group and 27 comprising the M/G-CHD group. Of the M/G-CHD patients, 13 had CHD of great complexity (including 6 single ventricle/Fontan and 2 atrial switch patients). Patients with M/G-CHD were older, had higher BMI, had higher incidence of ventricular dysfunction, and greater incidence of complex arrhythmias. Fluoroscopy-free ablation was achieved in 59% of M/G-CHD and 69% of S/N-CHD patients. Both groups had similar rates of acute procedural success, recurrence, and complications. Fluoroscopy was primarily used to visualize pre-existing transvenous leads and peripheral venous anomalies or to guide transbaffle/transseptal puncture.

CONCLUSIONS

A fluoroscopy-free ablation approach is feasible, safe, and successful even in patients with M/G-CHD with comparable outcomes to those with S/N-CHD.

The impact of current strategy using intracardiac echocardiography, lesion index, and minimum substrate ablation on clinical outcomes after catheter ablation procedure for atrial fibrillation

PURPOSE

We developed the intracardiac echocardiography (ICE) technique to minimize radiation exposure and other recent technology during ablation procedure for atrial fibrillation (AF). The aim of this study was to validate the impact of the current strategy using the recent technology for AF ablation on outcomes after procedure.

METHODS

We evaluated the safety and efficacy of the current strategy in consecutive set of patients undergoing first-time ablation for AF (N = 233) compared with the conventional strategy in earlier consecutive set of patients (N = 223). The current strategy included the technique of ICE to reduce radiation exposure, Ablation Index®-guided pulmonary veins isolation, and minimum substrate ablation targeting only for induced AF. Outcome measures were radiation exposure, procedure time, in-hospital adverse outcomes, and event-free survival from tachyarrhythmias.

RESULTS

Puncture-to-ablation time was slightly, but significantly increased in the current strategy than in the conventional strategy (48.0 minutes vs 44.7 minutes, P = .002), although total procedure time was significantly decreased in the current strategy (143.9 minutes vs 156.9 minutes, P < .001). Likewise, radiation time and absorbed dose were significantly decreased in the current strategy (9.8 minutes vs 38.8 minutes, P < .001; 102.3 mGy vs 490.5 mGy, P < .001). The incidence of overall in-hospital adverse outcomes was 3.9% in the current strategy and each complication rate was comparable with the conventional protocol. The event-free survival from recurrent atrial tachyarrhythmias was not significantly different between two groups (72.3% vs 77.1% at 2-year, P = .32).

CONCLUSION

The current strategy using the recent technology with ICE, lesion index, and minimum substrate ablation was feasible and reduced total procedure time and radiation exposure. However, the arrhythmia-free survival could not be improved.

Minimising radiation exposure in catheter ablation of ventricular arrhythmias

Background

Conventional fluoroscopy guided catheter ablation (CA) is an established treatment option for ventricular arrhythmias (VAs). However, with the complex nature of most procedures, patients and staff bare an increased radiation exposure. Near-zero or zero-fluoroscopy CA is an alternative method which could substantially reduce or even eliminate the radiation dose. Our aim was to analyse procedural outcomes with fluoroscopy minimising approach for treatment of VAs in patients with structurally normal hearts (SNH) and structural heart disease (SHD).

Methods

Fifty-two (age 53.4 ± 17.8 years, 38 male, 14 female) consecutive patients who underwent CA of VAs in our institution between May 2018 and December 2019 were included. Procedures were performed primarily with the aid of the three-dimensional electro-anatomical mapping system and intra-cardiac echocardiography. Fluoroscopy was considered only in left ventricular (LV) summit mapping for coronary angiography and when epicardial approach was planned. Acute and long-term procedural outcomes were analysed.

Results

Sixty CA procedures were performed. Twenty-five patients had SHD-related VAs (Group 1) and 27 patients had SNH (Group 2). While Group 1 had significantly higher total procedural time (256.9 ± 71.7 vs 123.6 ± 42.2 min; p < 0.001) compared to Group 2, overall procedural success rate [77.4% (24/31) vs 89.7% (26/29); p = 0.20)] and recurrence rate after the first procedure [8/25, (32%) vs 8/27, (29.6%); p = 0.85] were similar in both groups. Fluoroscopy was used in 3 procedures in Group 1 where epicardial approach was needed and in 4 procedures in Group 2 where LV summit VAs were ablated. Overall procedure-related major complication rate was 5%.

Conclusions

Fluoroscopy minimising approach for CA of VAs is feasible and safe in patients with SHD and SNH. Fluoroscopy could not be completely abolished in VAs with epicardial and LV summit substrate location.

Intracardiac Echocardiography to Guide Non-fluoroscopic Electrophysiology Procedures

Intracardiac echocardiography (ICE) is the most practical method for online imaging during electrophysiological procedures. It allows guiding of complex catheter ablation procedures together with electroanatomical mapping systems, either with minimal or with zero fluoroscopy exposure. Besides safe and reproducible transseptal puncture, ICE helps to assess location and contact of the tip of the ablation catheter relative to specific anatomical structures. Another option is visualization of the arrhythmogenic substrate in patients with ventricular arrhythmias. This article describes the clinical utility of ICE in non-fluoroscopic electrophysiology procedures more in detail.