bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of early recurrences on late recurrences after pulmonary vein isolation with pulsed field ablation. A subanalysis from the EU-PORIA multicenter international registry
Authors: Bordignon S , Chun K R J , Neven K , Mulder B A , Kueffer T , Reichlin T , Hansen J , Blaauw Y , Ouss A , Reinsch N , Albrecht E , Boveda S , Schmidt B
Published: May 2024

Background

Early recurrences of atrial tachyarrhythmia (ERAT) are commonly observed after pulmonary vein isolation (PVI) with thermal energies. ERAT during the 90-day blanking period (BP) should not be considered therapy failure as the cardiac tissue is still healing and the long-term benefit of PVI may not be immediately apparent. With the introduction of pulsed field ablation (PFA), a non thermal, myocardial-specific ablation technology for atrial fibrillation (AF), the significance of ERAT following PVI is unclear.

Methods

EU-PORIA (EUropean real-world outcomes with Pulsed field ablatiOn in patients with symptomatic atRIAl fibrillation), a multicentre international registry, collected data from 1233 patients treated with the pentaspline PFA catheter. For the current analysis, patients with a previous AF ablation procedure, patients treated with lesions beyond PVI, and patients without complete follow up data (during and following the BP) were excluded. The rate and significance of ERAT following PFA PVI were analysed.

Results

This subanalysis included 1011 patients (38% female, 66±11 years old, 64% paroxysmal atrial fibrillation [PAF]). ERATs were recorded in 178/1011 (18%) of patients (16% in PAF and 21% in persAF, p=0,021). Notably, ERAT patients were older (67,1±11,4 Vs 65,4±10,9, p=0,015) and had a higher median CHA2DS2-VASc Score (2,5 [IQR:1-4] Vs 2 [IQR:1-3]; p=0,019). The 35-mm catheter was more often used in ERAT patients (48/178(27%) Vs 148/833(18%) – p=0,005). At a median follow-up of 365 days (IQR 347-390), 100/178(56%) of patients with ERAT had documented late recurrence (LR), compared to only 147/833(18%) of patients in sinus rhythm throughout BP (p<0,001). Kaplan Meier estimates for overall freedom from AF/AT outside of the BP was 77% at one year for all patients. Patients with ERAT had a significantly lower freedom from AF/AT compared to patients with no ERAT (42% vs 84%, log-rank p<0,001). The absence of ERAT was associated with long-term success independent of the type of AF (41% Vs 88% in PAF, 43% vs 74% in persistent AF; p<0,001 for both). Among ERAT patients, no additional predictors for LR were identified.

Conclusions

In this large multicentre international registry, early recurrence of atrial tachyarrhythmia following PFA PVI were recorded in 18% of patients. ERAT was associated with late recurrences in the majority of cases, independent of AF type. The need for a blanking period following non thermal energy ablation for atrial fibrillation should be further questioned.
Ultra-high density mapping for the evaluation of the antral scar extension after ablation with a radiofrequency balloon catheter in atrial fibrillation patients
Authors: Poggi S , Almorad A , Pandozzi C , Torri F , Strisciuglio T , Iuliano A , Russo M , Manfrin M , Galeazzi M , Bertagnolli L , Spiniello G , Stabile G , Chierchia G B
Published: May 2024

Background

The Heliostar radiofrequency (RF) balloon ablation catheter enables one-shot pulmonary veins isolation (PVI). The RF balloon by occluding the PV ostia creates an antral scar.

Purpose

We sought to investigate the extension of the antral scar by mean of ultra-high density mapping.

Methods

Paroxysmal and persistent atrial fibrillation (AF) patients undergoing first PVI ablation with the Heliostar catheter across 4 European centers were enrolled. Ultra-high density mapping of left atrium was performed with the Octaray catheter, a octa-spline mapping catheter before and after the ablation. All maps were acquired in sinus rhythm, patients in AF underwent electrical cardioversion before mapping. The bipolar voltage maps from each patients were analysed: the left atrial area < 0.2 mV was considered scar and was calculated before and after the ablation and the distance between left and right antral lesions at upper and inferior posterior wall were also calculated.

Results

Overall, 49 patients were enrolled, 82% were male, the mean age was 60±9 years, 66% had paroxysmal AF. PVI was achieved in 100% patients. The mean left atrial area was 209±44 cm2, the scar after the ablation was 9±4.6 %, with 49±11% of the posterior wall still viable (bipolar voltage > 0.5mV). The distance between left and right antral lesions at the upper posterior wall was 26.57 mm whereas at the inferior aspect was 29.59 mm.

Conclusions

The RF balloon catheter creates a wide antral scar during AF ablation although without compromising the integrity of the posterior wall.
Influence of audiovisual distraction on the feeling of stress, analgesic sedation and patient satisfaction during electrophysiological ablation procedures on the heart
Authors: Kupusovic J , Raschke R , Wakili R
Published: May 2024

Background

Distraction using audiovisual stimuli has mostly been researched in a paediatric population with the results showing an inhibiting effect on stress and anxiety as well as the subjective perception of pain.

Purpose

We designed a study to test if audiovisual distraction may reduce the level of sedatives and analgesics by reducing anxiety and stress during electrophysiological intervention (EP).

Methods

We conducted a clinical intervention pilot study that was carried out in a randomized controlled manner. Consecutive 70 patients undergoing EP with subsequent ablation were randomized 1:1 to control (CTL) or intervention group (AVD). In addition to standardized sedation, all patients in AVD group received audiovisual glasses. Feeling of fear and stress was assessed through blood pressure changes. The patient satisfaction was assessed with Client Satisfaction Questionnaire, ZUF-8. Numeric scale (NRS) was used to quantify the perceived pain during the procedure. The difference between the subjective estimated duration of the procedure and the actual duration of the procedure was compared.

Results

The study included predominantly male patients (58.6%) with a mean age of 56 years. Technical aptitude was well balanced between both groups with the majority of patients in both groups owning a smartphone or a tablet (86.1% vs 85.7% for CTL and AVD respectively, p=0.92), and majority of patients in both groups using a computer, laptop or tablet on a weekly basis (58% vs 57.1% for CTL and AVD group respectively, p=0.97). The baseline feelings of anxiety were well balanced within both groups (Figure 1). Our analysis revealed no significant difference between the mean blood pressure values of the CTL and AVD groups (systolic: 135 vs. 141 mmHg; p = 0.32; diastolic: 74 vs. 72 mmHg; p = 0.45). Patient satisfaction score was comparable in both groups (26.5 vs. 26.8 points, p = 0.36). Average response for perceived pain using NRS scale as well as perceived procedure duration was similar between the groups (Figure 2). AVD group required a lower dose of Midazolam than CTL group (0.005 mg/kg/h vs 0.007 mg/kg/h, p = 0.07). Majority of patients (31.4%) in AVD group stated: "The audiovisual glasses made me feel distracted at times." 10% of the AVD patients stated: "The audiovisual glasses made me feel completely distracted and more relaxed."

Conclusion

The use of audiovisual glasses has no influence on the patients’ feelings of anxiety and stress during EP. The use of audiovisual glasses can temporarily induce distraction during EP, while they do not seem to be sufficient in reducing pain intensity during ablation therapy. Patients undergoing EP do not seem to be the target patient group for AVD use.
Left atrial posterior wall isolation during catheter ablation with the pulsed field ablation in patients with persistent atrial fibrillation
Authors: Schiavone M , Dello Russo A , Tondo C , Iacopino S , Bianchi S , Schillaci V , Moltrasio M , Rossillo A , Maggio R , Casella M , Filannino P , Volpato G , Themistoklakis S , Malacrida M , Solimene F
Published: May 2024

Background

Few data are available on pulsed-field ablation (PFA) targeting left atrial posterior wall (LAPW) in persistent atrial fibrillation (PeAF) patients.

Purpose

We sought to explore the role of PFA in persistent AF patients beyond pulmonary vein isolation (PVI), extending the lesion set to obtain LAPW isolation.

Methods

We enrolled consecutive patients referred for persistent AF catheter ablation using the Farapulse PFA system at nine Italian centers. Complete 3D mapping was performed before and immediately after LAPW isolation to validate our workflow in all cases. To analyze lesions' formation and residual gaps, the line around each pair of PVs was divided into 7 distinct sections in accordance with the literature, while the roof line, the floor line, and the two longitudinal posterior wall lines were equally divided into three parts. The PW was overall divided into nine regions. This scheme has been illustrated in Figure 1, Panel A.

Results

Fifty patients meeting inclusion criteria were included. PVI was achieved in all 202 (100%) PVs (1 patient exhibited a left common trunk, 2 patients exhibited a right middle cardiac PV). One-hundred ninety-eight (98.0%) PVs were acutely isolated on first pass, as confirmed by both entrance and exit block on subsequent 3D-mapping with the mapping catheter. A total of 7 PV gaps were detected through 3D mapping: 4 at the RSPV, 2 at the RIPV and 1 at the LSPV. When considering LAPWI, overall LAPW ablated area was 20.0±6 cm2 with lesions being deployed with the PFA catheter maneuvered in the flower configuration from one LAPW area to another. First-pass roof area (sectors #1 to #3) block was achieved in 44 (88%), first-pass floor area (sectors #7 to #9) block in 43 (86%) and inner-area (sectors #3 to #6) block in 45 (90%). A total of 23 residual LAPW activity gaps were detected through validation using high-output pacing and 3D mapping. Remapping examples has been reported in Figure 1, panel B-C-D. Evaluation of individual segments of the LAPW via signals’ assessment from the PFA splines demonstrated an accuracy of 94.9% (437 out of 450 sectors), compared to the results of subsequent high-output pacing and 3D mapping. Following PFA consolidation in these areas, LAPW isolation was successfully achieved in all cases (100%) using PFA alone, with no need for radiofrequency touch-ups. No major procedure-related adverse events were reported.

Conclusion

A structured workflow with the novel Farapulse PFA system allowed for a reliable, safe, and fast LAPW isolation, as confirmed by ultra-high-density 3D mapping.
Safety and feasibility of zero-fluoroscopy technique in ablation-index guided pulmonary vein isolation: a prospective, single center trial
Authors: Torma D , Debreceni D , Janosi K F , Simor T , Kupo P
Published: May 2024

Introduction

Pulmonary vein isolation (PVI) represents the cornerstone of catheter ablation procedures in patients with symptomatic paroxysmal/persistent atrial fibrillation (AF). Conventionally, PVI is performed using fluoroscopy, but it can also be performed using the zero-fluoroscopy (ZF) technique with the assistance of electroanatomical mapping systems and intracardiac ultrasound, achieving fluoroscopy-free procedures.

Purpose

Our study aimed to compare procedural data of ablation-index guided point-by-point radiofrequency (RF) PVI performed with non-zero-fluoroscopy (NZF) vs. ZF approaches.

Methods

We enrolled 100 consecutive patients undergoing PVI for antiarrhythmic drug- refractory AF in our prospective observational study. In the first 50 cases, PVI was performed using the NZF technique, and in the other 50 cases, the ZF technique was applied. Procedural time, fluoroscopy exposure, ablation parameters, and the occurrence of complications were compared between the two groups.

Results

Compared to the NZF group, procedural time (59.6±10.7 min vs. 74.6±13.2 min, p<0.0001) was significantly shorter in the ZF group. This difference was mainly driven by the time from puncture to the beginning of left atrial mapping, which was significantly longer in the NZF group (17 [16; 20] min vs. 31 [23; 34.5] min, p<0.001). No differences were found between the two approaches in the number of RF applications (81 [73; 103] vs. 83 [71; 91], p=0.67), total ablation energy (54986 ± 13093 Ws vs. 55500 ± 11907 Ws, p=0.48), and the left atrial dwelling time (41.5 [36; 52.5] min vs. 40.5 [35; 46], p=0.14). No complications occurred in either group. In the ZF group, complete elimination of fluoroscopy was achieved in all cases, resulting in significant differences in 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) compared to the NZF technique. The acute success rate was 100% in the study population, and no complications occurred during the study period.

Conclusion

Ablation-index guided ZF PVI is feasible and safe. Using this technique, the procedure time can be shortened besides achieving a similar acute success rate without increasing complications.
Preventing vagal response during pulmonary vein isolation with pulsed field ablation: impact of the order of the targeted pulmonary veins
Authors: Del Monte A , Della Rocca D G , Pannone L , Vetta G , Cespon Fernandez M , Doundoulakis I , Marcon L , Monaco C , Bala G , Stroker E , Sieira J , Almorad A , Sarkozy A , Chierchia G B , De Asmundis C
Published: May 2024

Background

Vagal responses are frequently observed during pulmonary vein isolation (PVI). Radiofrequency ablation of the anterior right ganglionated plexus (ARGP) before PVI has been demonstrated to effectively prevent VR occurrence. Pulsed-field ablation (PFA) has emerged as an alternative energy source for PVI. Despite PFA being selective for the myocardium, intraprocedural VRs and reversible effects on ganglionated plexi (GP) have been documented during PVI.

Purpose

We aimed to investigate whether initiating PVI from the right superior pulmonary vein (RSPV) before any other pulmonary veins (PVs) could prevent VR occurrence via concomitant transient ARGP modulation.

Methods

60 consecutive paroxysmal atrial fibrillation patients undergoing PVI with the pentaspline PFA ablation catheter were prospectively included. In the first 30 patients, PVI was started from the left superior pulmonary vein (LSPV-first group). In the last 30 patients, the RSPV was targeted first, followed by the left PVs, and finally the right inferior PV (RSPV-first group). VR was defined as sinus bradycardia (<40 beats/min), asystole, or atrioventricular block (AVB). Heart rate (HR) was evaluated at baseline, during PVI, and post-ablation to assess GP modulation.

Results

Baseline characteristics were similar between the two study groups. VR during PVI occurred in 22 (73%) patients in the LSPV-first group and 3 (10%) in the RSPV-first group (Figure1, p<0.001). A higher rate of VRs was observed in patients in the LSPV-first group compared to patients in the RSPV-first group during ablation of the LSPV and LIPV (73% vs. 7%, p<0.001 and 27% vs. 0%, p=0.005, respectively), while no differences were found during ablation of the right PVs. Temporary pacing was employed in 10 (33%) patients in the LSPV-first group and 3 (10%) in the RSPV-first group (p=0.028). RSPV isolation induced similar acute HR increase in the two groups (13±9 bpm vs 13±10 bpm, p=0.9). However, no significant HR variation was documented in both groups at the end of the procedure compared to baseline (all p>0.05).

Conclusion

PVI with PFA is frequently associated with intraprocedural VRs when ablation is initiated from the LSPV. However, an RSPV-first approach determined transient HR increase and reduced VR occurrence.Figure 1
Functional substrate mapping characteristics during sinus rhythm predicts critical isthmus of scar related atrial tachycardia
Authors: Yorgun H , Coteli C , Kilic S , Aytemir K
Published: May 2024

Background

Atrial tachycardia (AT) is a common rhythm disorder in patients with underlying atrial scar due to previous atrial surgery or valvular heart disease. Data is scarce about the role of functional characteristics or conduction properties during sinus rhythm that may have role in the critical isthmus (CI) of re-entry.

Purpose

We aimed to evaluate the relationship between the functional substrate mapping (FSM) characteristics of right and left atrium and the CI of re-entrant ATs in patients with atrial low-voltage areas.

Methods

A total of 95 [mean age: 57 ± 13, gender: 57 (60%) female] symptomatic patients with history of left and right AT who underwent catheter ablation with 3-D high-density mapping were enrolled. Isochronal late activation mapping were created during sinus/paced rhythm to detect deceleration zones (DZ). After induction of AT, activation mapping was performed in all patients.

Results

In 95 patients, 96 left-ATs [49 (51%) ATs were macroreentry and 47 (49%) ATs were localized reentry] and 40 right-ATs [24 (60%) ATs were macroreentry and 16 (40%) ATs were localized reentry] were mapped. Atrial low voltage zones comprised 23.3 ± 13.0 % of total right atrium and 33.3 ± 21.2 % of total left atrium. The mean value of bipolar voltage, EGM duration, and conduction velocity during sinus rhythm corresponding to CI of ATs were 0.17 ± 0.10 mV, 121 ± 39 ms, and 0.09 ± 0.06 m/s, respectively. Total number of DZs were 125 and all CIs of reentry were colocalized with DZs detected during FSM. The positive predictive value of DZs to detect CI of inducible ATs is 87.2%. Freedom from ATa was 76.8% at 12 months follow-up.

Conclusion

Our findings demonstrated the utility of FSM during sinus rhythm to predict the successful termination sites for ATs. These areas displayed continuous-fragmented signal morphology in correlation with the CI of AT detected during activation mapping.
Differentiation of high frequency near field versus far-field potentials in low voltage zones during sinus rhythm improves discrimination of local sites of termination during ventricular tachycardia
Authors: Merino Fuentes D , Handayani A , Castrejon Castrejon S , Guido Lopez L , Martinez Cossiani M , Jauregui Abularach M , Sanchez Somonte P , Martinez Maldonado M E , Sanz Verdejo B , Merino Llorens J L
Published: May 2024

Background

Ventricular tachycardia (VT) with structural heart disease (SHD) is often bad tolerated or presents with several inducible morphologies, this support mapping the arrhythmic substrate during sinus rhythm (SR). Poor discrimination between near-field (NF) and far-field (FF) electrogram (EGM) components in low voltage (LV) areas is the main limitation. The peak frequency (PF) associated with bipolar EGMs may distinguish NF from FF EGMs (Panel D).

Objective

To evaluate if PF combined with voltage mapping during SR enhances discrimination of the region of VT termination by radiofrequency application (RFa).

Methods

Bipolar activation and voltage maps were generated with a 16-pole grid catheter (HD Grid) during SR (Panel B). PF maps were retrospectively computed (Panel C). The maps were only analyzed if acute termination was achieved by focal RFa within a boundary diameter <1.5cm (Panel A). The mapped surface area (SA) was sub-regioned in termination (T-ZONE) and non-termination (NT-ZONE) zones. The T-ZONE surface was centered about the termination site and was allowed to extend to a rectangular kernel >0.5cm and <1.5cm across perpendicular axes, with the NT-ZONE encompassing the remainder mapped SA. Sensitivity (SE) and specificity (SP) of discrimination of the T-ZONE vs. NT-ZONE were measured according to the %SA covered at different LV thresholds (0.1-1.0mV in increments of 0.1mV - Panel F). LV high PF (LVHF) areas at different PF cutoffs from 150Hz (LVHF150) to 300Hz (LVHF300) were also assessed.

Results

15 patients with SHD and sustained monomorphic VT were enrolled. 4 had 5 VT’s terminated by 1.4±0.9 focal RF lesions (60-74 y/o, 3 ischemic). All termination sites were located in a LVHF region mapped during SR (Panels B,C,E). The T-ZONE occupied 0.41±0.33cm /92.75±13.31cm global SA and consisted of 15±10 EGM points/1432±337 global points. T-ZONE voltage during SR (0.50±0.32mV) was significantly lower vs. global voltage (2.01±0.69mV, P<0.001), while T-ZONE PF was higher (324±51Hz) vs. global (270±37Hz, P<0.001). ROC discrimination of the T-ZONE yielded AUC’s of 0.79-LV alone, 0.87- LVHF150, 0.91-LVHF200 (Delta +12.2% vs LV alone, Panel F), 0.85-LVHF250 and 0.77-LVHF300. At a 0.7mV cutoff, LVHF200 yielded a balanced SE/SP of 0.89/0.87 vs. LV alone (0.90/0.63).

Conclusion

Assessment of regions with LVHF during SR improves SP for discrimination of sites of VT termination compared to LV alone.TV near field
Local impedance drop as a predictor of sucessful pulmonary vein isolation
Authors: Montilla Padilla I , Alfonso Almazan J M , Marin Garcia I , Lopez Rodriguez G , Ramos Maqueda J
Published: May 2024

1. Introduction

Pulmonary vein isolation (PVI) is the cornerstone of AF treatment. An accurate estimation of the lesion size and a optimal evaluation of the catheter-myocardium coupling is crucial for achieving an effective and safe radiofrequency (RF) ablation. A few studies have suggested that local impedance (LI) drop is a better predictor than general impedance drop in terms of lesion size, electrical coupling and therefore acute PVI success. An open-irrigated ablation catheter designed to measure contact force (CF) and LI drop while applying RF has been recently developed.

2. Purpose

The aim of this study is to evaluate if conduction GAPS are located in certain areas and if LI drop can predict the presence of conduction gaps in each of these segments.

3. Methods

Observational prospective study including 55 consecutive patients who underwent PVI. The RF lesions were delivered with 30 W (posterior wall) or 35 W (anterior wall) for a maximum of 30 seg with a CF > 5 g. The applications were stopped if a LI of 35 Ohm was reached on the posterior wall or 40 Ohm on the anterior wall.

PVs were divided into seven segments and ablation tags were assigned to a segment according to their anatomical position (figure 1) We categorized the tags included in each segment as successful or not according to the presence of conduction gaps detected with an Ultrahigh density mapping catheter once the WACA was completed. At the same time lesion by lesion were studied regardless of the segment where it was located.

4. Results

We analyzed 4002 lesion tags of 55 patients who underwent PVI. 53 Gaps were found in 19/55 (34.5%) left WACA and 16/54 (29,6%) right WACA and were localized predominantly in three PVI segments (L1, L6 and R3) 34(54.85%) vs 19 (35,8%) (L2-L5, L7, R1-R2, R4-R7) (p<0.001) (figure 1). They were mainly circumscribed to anterior segments in left PVs and posterior-superior segment in right PVs (figure1).

When examining lesions independently of their location we found a significant difference in LI drop among successful and unsuccessful lesions (24.22±8.31 vs 15.67±7.85) Ohm, p<0.001).

In the same line when studying lesions in those segments with > 10% of GAPS (L1, L6 R1 and R3) LI drop was greater in successful lesion tags: L1 25.2 ± 5.35 vs 16.8 ± 5.17 (p<0.001), L6 25.2±5.7 vs 16±5.48 (p<0.001), R1 27.9±4.78 vs 17.1±5.73 (p=0.03) and R3 18.5±5.4 vs 10.7±2.49 (p<0.001).

5. Conclusions

Gaps were located predominantly in anterior segments in left PVs and posterior-superior segment in right PVs. A low LI drop was an excellent predictor of conduction gaps, and it performs well regardless of the segment where it was analyzedFig. 1
Implementation of near zero fluoroscopy in supraventricular tachycardia ablation procedures: a single center experience
Authors: Lebreiro A , Pestana G , Madeira M , Alves Pinto R , Pinto R , Araujo P , Martins C , Adao L
Published: May 2024

Background

Supraventricular tachycardia (SVT) are common cardiac arrhythmias, and catheter ablation has proven to be a very effective treatment, but exposes patients and healthcare providers to radiation. "Near Zero Fluoroscopy" (NZF) techniques, utilizing advanced imaging, aim to reduce radiation exposure while maintaining efficacy.

Purpose

To present an analysis of near-zero fluoroscopy in SVT ablation procedures, in a tertiary center, since its implementation.

Methods

We prospectively enrolled 446 SVT-diagnosed patients for this study. All of them underwent NZF procedures using the same specific 3D mapping system, between January/19 and December/22. Patients with atrial fibrillation or macroreentrant atrial tachycardias or when a different mapping system was used, were excluded. All patients provided informed consent.

Results

Our population had 266 (60%) females and a median age of 39 (IQR 24-51) years.

AVNRT was the most frequent arrhythmia documented (229 cases, 51%), followed by Accessory Pathways (AP) (201 cases, 45%) and focal atrial tachycardia (AT) (16 cases, 4%). The ablation success rate was high (405/418, 97%). There was no ablation attempt in 12 patients (9 APs and 3 ATs) and the unsuccessful ablations (7/418 cases, 1,67%) were APs. Overall, fluoroscopy time was 1.1 minutes (IQR 0-2.6). There was no statistically significant difference in the distribution of fluoroscopy time among the types of SVT based on the Kruskal-Wallis test (p 0.14).

Observing trends of fluoroscopy use through time, we acknowledge the presence of a learning curve, leading towards shorter times of X-ray during procedures along the first 3 years of implementation of a near-zero strategy. Median times (IQR) of fluoroscopy were as follows: 2019 – 2.25 (0.45-3.4) min; 2020 – 1 (0-2.5) min; 2021 – 0 (0-1.9) min; 2022 – 0.55 (03.05) min. (see BoxPlot) Pairwise comparisons using the Wilcoxon rank-sum test with continuity correction revealed statistically significant differences in medians between all pairs of years, with p-values adjusted for multiple comparisons using the Bonferroni method (p<0.01). In 2022, fluoroscopy time increased, when compared to 2021. We believe this finding can be explained by the fact that in 2022, our department received a new fellow and a young EP consultant (coming from a center where NZF was not the standard for SVT ablation), both being in the lab on a daily basis, explaining this upward trend in fluoroscopy time.

There were no acute complications requiring hospital admission or active treatment.

Conclusion

Our results emphasize the potential of near-zero fluoroscopy techniques to enhance safety and reduce radiation exposure while maintaining a high level of procedural efficacy in the treatment of SVT cases. Absence of acute complications highlighted the safety of these approaches.
Activation map of koch triangle: a novel approach to AVNRT ablation using CARTO 3 v7
Authors: Chieffo E , Carrozzi C , Cacucci M , D'amore S , Dossena C , Landolina M E
Published: May 2024

Background

Ablation of slow pathway (SP) is the standard approach for atrioventricular nodal reentry tachycardia (AVNRT) treatment (1). Low-voltage bridge is an optimal target during mapping using low x-ray exposure (2,3).

Purpose

We want to assess a new tool to identify SP by activation mapping of Koch’s triangle using CARTO PRIME V7

Methods

Triangle of Koch 3D-activation map were obtained from intracardiac contact mapping during low x-ray CARTO 3 procedures (Figure 1). In 60 patients (39 % males, mean age 60.3 ± 14.7 years) undergoing ablation for AVNRT, an automatic activation map using a DECANAV mapping catheter and CARTO Confidense, Coherent, and FAM DX software modules were obtained.

Results

We indentified SP in all patients as the latest atrioventricular node activation area; RF catheter ablation (RFCA) elicited junctional beats. The mean dose-area product (DAP) was 16.5 ± 2.7 cGy/cm2, the mean fluoroscopy time exposure was 2.9 ± 2 min, the mean ablation index was 428.6 ± 96.6, and the mean contact force was 8 ± 2.8 g. There were no adverse event during the procedure and no AVNRT recurrences during a mean follow-up of 14.3 ± 8.3 months.

Conclusions

Ablation of the SP by automatic mapping using Confidense, Coherent, and FAM DX software modules is a new approach to AVNRT ablation. The CARTO3 V7 system defines a 3D map of the latest AV node activation area during sinus rhythm allowing a highly effective RFCA under low fluoroscopy time exposure without recurrences or AV blocks.Figure 1
The challenge of transseptal access for catheter ablation of left-sided arrhythmia substrate in infants and small children under 6 years of age
Authors: Nagy Z , Szabo A , Csakany L , Major T , Som Z , Foldesi C , Kornyei L
Published: May 2024

Background

Young age and small cardiac dimensions are increased risk factors for catheter ablation (CA), therefore ablation below 15 kg should be recommended only in selected drug-refractory cases. The need for a transseptal puncture (TSP) may be an additional risk factor. Persistent foramen ovale (PFO) in infants can mitigate this risk and paradoxically, decrease the complication rate in the very young.

Purpose

This study aimed to compare the results of left-sided CA in infants under 1 year and in children between 1-6 years of age.

Methods

Between January 2010 and September 2023, 1703 pediatric CAs were performed, of which 17 left-sided ablations in children under 6 years without structural heart disease were retrospectively evaluated. CA results below 1 year and between 1-6 years of age were compared in terms of body size, procedural parameters, left atrial (LA) access, complication, and success rate.

Results

The patient group below 1 year (Group 1, n=5) has a mean age=0.13±0.03 years, mean body weight=3.6±1.1 kg, mean height=52.3±3.6 cm. Patients between 1-6 years (Group 2, n=12) have mean age=5.0±1.1 years, mean body weight=17.9±2.2 kg, mean height=111.2±7.4 cm. The arrhythmia substrate was an overt pathway in 3 pts (17.6%), concealed accessory pathway in 7 pts (41.2%), and focal LA tachycardia in 7 pts (41.2%). Foramen ovale was persistent in all 5 children in Group 1 and TSP was not required. In Group 2, only 2 pts (16.7%) had PFO, and, all other procedures required TSP. TSP was successful in 9/10 cases (90%). No complications related to LA access or other adverse events occurred in Group 1. In Group 2, there was one case of pericardial effusion that spontaneously regressed and one case of mechanical-induced advanced AV block that resolved after six days. There were no significant differences in procedure time, fluoroscopic time, and radiation dose between the two groups (Group 1: 126.4±47.0 min, 6.4±4.5 min, 4.0±5.3 cGycm2 vs. Group 2: 162.6±49.2 min, 7.9±9.4 min, 9.0±12.4 cGycm2, p>0.05). All CAs were performed with RF energy. The acute success rate of the procedures was 100%.

Conclusion

CA of left-sided arrhythmias in infants and small children may offer a safe and effective therapeutic option in selected cases. The high prevalence of PFO may explain the paradoxically less complication under 1 year of age.
Safety and efficacy outcomes in 100 consecutive cases of pulsed field ablation
Authors: Murray P , O'hare D
Published: May 2024

Background

Pulsed field ablation (PFA) an emerging technology for ablation of atrial fibrillation (AF). This non-thermal ablation modality uses ultrarapid electrical pulses to destabilise cell membranes and can selectively ablate myocardial tissue. Successful pulmonary vein isolation (PVI) and reductions in procedure times compared to other modalities have been observed in initial studies.

Aim

To report initial outcomes and fluoroscopic times in the first 100 consecutive cases using PFA in AF ablation.

Methods

The first 100 consecutive PFA cases carried out by a single operator in a single centre were examined. All cases were performed under general anaesthesia, using ultrasound-guided vascular access and TOE-guided transseptal puncture. Outcomes were recorded from the first case in June 2022 to the present day. Electroanatomic mapping (EAM) was carried out using two proprietary systems.

Results

Procedural information and follow-up was achieved in all 100 patients (see table). The majority (77) were male. Mean age 61. Cardiovascular comorbidities included: hypertension (41), heart failure (12), ischaemic heart disease (10), stroke (4), diabetes mellitus (3). Antiarrhythmic drugs were used by 45 patients (Amiodarone in 22, Dronedarone in 18, Flecainide in 10, Sotalol in 8, Mexiletine in 1) with 55 taking beta blockers only or no rhythm control drugs. Persistent AF accounted for 57 cases, and 91 patients had no prior ablation procedure.

Median CHA2DS2VASC 1. Warfarin was used on 1 patient, the other 99 patients underwent ablation on uninterrupted DOAC, most commonly Apixaban. EAM was conducted in 59 patients. Stand-alone PVI was carried out in 68, while 30 underwent an additional posterior wall box isolation, and a mitral isthmus line was added in a further 2 who had atrial flutter (AFl) during the procedure following successful PVI.

There were no serious peri-procedural complications. (vascular access complications, pericardial effusion, stroke or death). All 100 patients were discharged following a one-night stay. Clinical pericarditis without effusion occurred in 1 patient on day 2, and resolved with a short course of Colchicine.

Mean fluoroscopy time was 9minutes, 12seconds, and reductions in fluoroscopy times correlated significantly with case number (see figure). Mean fluoroscopy time was 2mins, 30secs higher where EAM was used. Sinus rhythm was achieved in 100%. Atrial arrhythmia recurred in 12 patients, 7 with AF and 3 atrial flutter, 2 with typical symptoms which could not be documented. Two of the recurrences were within 24 hours of the procedure.

Conclusions

This registry data shows that PFA was used to achieve PVI safely, with effective additional substrate ablation also demonstrated. There were no serious peri-procedural complications, and procedural improvements in fluoroscopic times were observed throughout the 100 cases. Long term follow-up data is required to validate the safety and efficacy of this new technology.
Focal pulsed field ablation for organised atrial tachyarrhythmias: one to rule them all
Authors: Sikiric I , Jurisic Z , Breskovic T , Lisica L , Dagelic M , Katic J , Anic A
Published: May 2024

Background

Focal pulsed field ablation (fPFA) has emerged as a versatile and innovative strategy for ablating atrial tachyarrhythmias (1). The primary objective of this study is to present the short-term safety characteristics, feasibility and procedural outcomes of fPFA in the management of organised atrial tachyarrhythmias. This report focuses on the commercial use of an innovative pulsed field ablation (PFA) generator, utilized in conjunction with commercially available focal, solid-tip ablation catheters, and complemented by 3D electro-anatomical mapping (3D-EAM).

Methods

Patients with organised atrial tachycardia treated using fPFA between August 2022 and September 2023 at our center were included in this retrospective analysis. Tachycardia mechanisms were identified with high-definition, multi-electrode mapping catheter paired with 3D-EAM system. Ablation lines, when targeting macro-reentrant arrhythmias were strategicaly positioned to adress critical isthmi when recognised or they were empirically placed between the anatomical obstacles ( including LA roof, anterior, mitral isthmus, upper septal and cavotricuspid line as deemed appropriate). Positioning of the fPFA catheter was guided by 3D-EAM, intracardiac ultrasound, and fluoroscopy (Figure 1). Bidirectional block verification was performed using standard criteria to assess acute procedural success. Glyceryl trinitrate boluses were administered prior to ablation in proximity to coronary arteries.

Results

In a cohort of 36 patients (median age 62 years; 12 females), we effectively mapped and treated a total of 51 distinct organised atrial tachyarrhythmias. These included 18 typical flutters, 3 roof-dependent macro-reentries, 4 posterior-wall micro-reentries, 15 peri-mitral macro-reentries, 8 anterior-wall micro-reentries and 3 biatrial macro-reentries via Bachman bundle. Our ablation strategy involved creating 21 cavotricuspid isthmus lines, 3 roof lines, 18 posterior wall lines, 11 anterior lines, 8 septal lines, and 15 mitral isthmus lines (Figure 2). Impressively, first-pass acute isolation with bidirectional block was achieved in 93% (54 of 58) of isthmus ablations and 94% (17 of 18) of left posterior wall lines. No ST segment alterations or other complications were observed during the periprocedural period.

Conclusion

In our cohort fPFA proved as a feasible, effective, and safe approach for treating organised atrial tacharrhythmias. The primary reason for designating this setup as our preferred choice for redo procedures lies in its versatility in addressing a wide range of arrhythmias. As ultra-fast pulmonary vein isolation (PVI) procedures become more prevalent with the expansion of PFA, the demand for an ideal setup capable of effectively targeting various substrates will become even more pronounced (2). Notably, our findings suggest superior suitability and efficacy when compared to bulkier, single-shot design PFA devices (3).Figure 1Figure 2
Identification of deceleration zones during sinus rhythm for locating critical isthmuses in left atrial macroreentrant tachycardias
Authors: Martinez Cossiani M , Castrejon S , Sanroman-Junquera M , Guido L , Merino D , Relan J , Kim S , De La Vieja Alarcon J J , Jauregui Abularach M E , Sanchez Somonte P , Martinez Maldonado M E , Handayani A , Sanz Verdejo B , Escobar Cervantes C , Merino J L
Published: May 2024

Introduction

Ablation of left atrial (LA) macroreentrant tachycardias (LAMT) poses considerable challenges, with issues such as tachycardia cycle length variations, multiple reentrant circuits, and tachycardia termination during entrainment maneuvers. Evaluating deceleration zones (DZ) through atrial pacing during sinus rhythm, and their correlation with potential critical conduction isthmuses (CI) in LAMT, remains unexplored. This approach may facilitate LAMT ablation.

Objective

To investigate the presence of DZ through atrial pacing during sinus rhythm and their association with LAMT critical conduction isthmuses (CI).

Methods

Patients who underwent LAMT high-density activation mapping with a 16-pole grid catheter were included. Conventional mapping (activation, voltage and entrainment mapping during tachycardia) was performed to localize the CI. Atrial pacing with three atrial extrastimuli (S2/S3/S4 with 500/500/300 ms coupling interval) was performed during sinus rhythm from the distal coronary sinus (CS). Isochronal late activation mapping (ILAM) of the S3 and S4 cycles was compared. Deceleration zones (DZ) were defined as an offset in the color scale of the activation map in an area with at least a radius of 10 mm. ILAMs were evaluated blindly, and DZs were compared with CIs defined by conventional mapping during tachycardia and validated by radiofrequency application termination.

Results

18 p (60.50 ± 11.63 yo, 11 male) and 21 procedures were included. LAMT termination was successful in 18 out of 21 procedures (85.71%) and failed in 3 due to the epicardial component of the reentrant circuit. ILAM during CS pacing was achieved in 13 patients and was not possible in 5 p due to multiple LAMTs leading to empiric linear ablation in 1 and to recurrent induction of LAMT or AF during the pacing protocol. A DZ was identified in 13 out of 16 maps (81.25%) in the S3 map, which was more pronounced in the S4 map. In all these 13 maps, the final ablation site was within the DZ in the S4 map, terminating the tachycardia with focal RF applications in 11 and with extended in 2.

Conclusions

Deceleration zones identified through atrial pacing during sinus rhythm are prevalent in LAMT patients. These zones generally correspond to the critical conduction isthmus and offer a valuable method for mapping the reentrant circuit when mapping during stable LAMT is not feasible.
Validation of predictive models for lesion transmurality and steam-pop using ex-vivo porcine bipolar ablation model
Authors: Kamioka M , Makimoto H , Watanabe T , Watanabe H , Yokota A , Komori T , Kabutoya T , Imai Y , Kario K
Published: May 2024

Introduction

Bipolar ablation has been reported to create deeper myocardial ablation lesion as compared to unipolar ablation, however, there is currently no standardized strategy for bipolar ablation settings such as energy and ablation time.

Purpose

The aim of the present study is to test our hypothesis that both transmural lesion creation and steam-pop occurrence during bipolar ablation can be predicted by the settings of bipolar ablation and the myocardial tissue characteristics such as tissue thickness and initial impedance prior to RF.

Methods

Using porcine cardiac tissues, we conducted ex-vivo ablation experiments. Commercially available radiofrequency (RF) ablation catheters were utilized for the procedures. Each ablation catheter was positioned bilaterally on the myocardial slices at a 45-degree angle, maintaining a targeted contact force of 10g. We documented the occurrence of steam-pop under various conditions, modulating tissue thickness (5-20 mm), RF power (20, 30, 40, 50 Watt) and ablation duration (20 sec, 40 sec, 60 sec, 180 sec). Generalized linear models (GLM) were developed to forecast the creation of transmural lesion and steam-pop incidents, drawing on the bipolar ablation settings and myocardial tissue characteristics. Subsequently, we engaged in an additional series of experiments to validate the models.

Results

In total, 194 bipolar applications were utilized as training data. Transmural lesions and steam-pops were observed in 95 (49%), and 11 applications (5.7%), respectively. We constructed GLM using the RF energy (Watt), tissue thickness (mm), initial bipolar impedance (Ohm), impedance drop during the first 5 seconds of application (Ohm), and RF duration (seconds). For transmurality prediction the model validation was conducted with another independent 111 RF applications (102 transmural, and 25 steam-pops). The GLM, which utilized RF energy, tissue thickness, initial bipolar impedance, and RF duration, performed the best performance in predicting transmural lesion creation (AUC 0.94 [0.90-0.99], sensitivity 86 %, specificity 100 %). However, the exclusion of ‘tissue thickness’ from this model led to a significant decrease in its predictive performance (AUC 0.69 [0.48-0.89], sensitivity 47%, specificity 100%, P=0.0057). For pop prediction in validation data, the GLM utilizing RF energy, initial bipolar impedance and impedance drop showed the best performance (AUC 0.90 [0.83-0.97], sensitivity 76 %, specificity 92 %).

Conclusion

Our data show that accurate assessment of tissue thickness is pivotal for predicting transmural lesion creation. To predict lesion transmurality and steam-pop incidents through RF parameters and tissue characteristics within a beating heart, further research is warranted. This could facilitate the calibration of RF settings, potentially enhancing the safety of bipolar ablation procedures.
Associations between atrial epicardial fat quantified by semi-automated CT segmentation and gender, BMI, cholesterol levels in AF patients: results from the prospective AFAT study
Authors: Erhard N , Prommersberger S , Neuner B , Bahlke F , Englert F , Popa M A , Krafft H , Abdiu E , Reents T , Kottmaier M , Telishevska M , Lengauer S , Hessling G , Bourier F , Deisenhofer I
Published: May 2024

Background

Epicardial adipose tissue (EAT) is defined as adipose tissue (epicardial fat) between the myocardium and the visceral pericardium. Recent evidence suggests that EAT may play important roles in regard to atrial fibrillation (AF) burden as well as other cardiovascular diseases through complex inflammatory mechanisms. Current evidence regarding the relationship of atrial EAT and BMI, gender or cardiovascular risk factors is mixed.

Methods and Results

We conducted a prospective observational study (AFAT) at the German Heart centre in Munich with 200 patients aimed to be included. This represents an interim analysis of the first 75 patients enrolled in the AFAT study. All patients received delayed dual source cardiac computer tomography (CT) imaging which was analysed using 3D segmentation (Figure 1) to quantify left atrial (LA) and right atrial (RA) EAT prior to receiving catheter ablation for AF.

The mean age was 67 ± 8.7 years with 46.9 % being female (n=35) and the mean BMI was 28 ± 4.5. Mean LA EAT was 33.1 ml ± 13.2 ml and RA EAT was 32.7 ml ± 12.2ml with a total mean atrial EAT volume of 65.4 ml ± 10.2 ml. Volumes of the left- and right atrial EAT were significantly correlated in our sample (p < 0.001; Pearson correlation coefficient r=0.9). The mean total EAT Volume was significantly larger in males than in females (74 ml vs. 52 ml, p < 0.001) (Figure 2). Linear regression analysis adjusted for cofounders demonstrated significantly larger mean atrial EAT volumes in patients with higher body mass index (p = 0.001) and with increased age (p=0.006). Increased HbA1c levels or increased total cholesterol levels were not associated with higher total atrial EAT Levels (respectively, p=0.066 and p=0.22).

Conclusion

Semi-automated CT based atrial segmentation is a novel highly accurate and reproducible way to reliably identify atrial EAT. Left and right atrial EAT volumes are significantly intercorrelated. In this study BMI, Age and male gender were independently associated with higher EAT levels.Visualization of atrial EATGender differences in atrial EAT (ml)
New joint model for the dynamic prediction of heart failure in phospholamban (PLN) p.(Arg14del) positive individuals
Authors: Van Der Heide M Y C , Verstraelen T E , Van Drie E , De Brouwer R , Proost V M , Houweling A C , Dickhoff C , Germans T , Gimeno-Blanes J R , Te Riele A S J M , Van Spaendonck-Zwarts K Y , Cox G P J , Van Tintelen J P , Zwinderman A H , Wilde A A M
Published: May 2024

Background

PLN p.(Arg14del) positive individuals are at risk for developing arrhythmogenic cardiomyopathy which can cause severe heart failure. Future gene therapy could be lifesaving and is rapidly advancing. It is therefore of importance to identify eligible patients for this evolving treatment, with individuals risk prediction playing an imperative role in this process.

Purpose

To develop a dynamic prediction model for the individual risk prediction of heart failure in PLN p.(Arg14del) positive individuals.

Method

Data were collected of 564 PLN p.(Arg14del) positive individuals with no baseline history of heart failure or myocardial infarction. During a median follow-up of 6.3 years (interquartile range 2.9-10.0), 74 individuals experienced heart failure, defined as a composite endpoint of heart failure hospitalization, left ventricle assist device implantation, heart transplantation and heart failure-related death. For the individual prediction of time to heart failure we used a joint model which simultaneously estimates a longitudinal model for repeatedly measured left ventricle ejection fraction (LVEF) during follow-up and a Cox regression model for the hazards of the heart failure endpoint. Using the longitudinal model we predicted the LVEF-values of all patients at future time points using the estimated random-effects and these predicted LVEF values were used as a time-dependent covariate in the Cox model which also contained age at start of follow-up as predictor variable.

Results

The joint model trained in this study had a very good performance in discriminating the individuals at risk for heart failure, with the 5-year mean AUC of 0.86 and 10-year mean AUC of 0.84. The LVEF had a hazard ratio of 0.89 (95% confidence interval (CI) 0.86-0.93, p<0.001), and age at baseline 1.04 (95% CI 1.03-1.06], p<0.001), meaning a lower LVEF and higher age at presentation were associated with heart failure. Figure 1 shows an example of an individual risk prediction with on the x-axis the follow-up time in years, on the y-axis (left) the LVEF in % and on the y-axis (right) the predicted survival probability.

Conclusion

Individual risk prediction with a simple model including only LVEF and age is of great importance for identifying PLN p.(Arg14del) positive individuals who are at risk of developing heart failure. The introduction of this novel joint prediction model is the first step in identifying individuals at risk for heart failure and may aid patient selection for future gene therapy interventions.