bluuebunny/crossref_metadata_2025_split huggingface dataset:
P420Improved real time recordings using the third generation cryoballoon technology - detection of dual fascicle electrograms
Authors: Velagic V , Prepolec I , Pasara V , Kardum D , Pezo-Nikolic B , Puljevic M , Matasic R , Krpan M , Lovric-Bencic M , Puljevic D , Milicic D 
Published: June 2020

Abstract

Introduction
The third-generation cryoballoon has been designed with a 40% shortened tip length compared with the former second-generation CB device. Ideally, a shorter tip could result with an improved visualization of real-time (RT) recordings in the pulmonary vein (PV) due to a more proximal positioning of the inner lumen mapping catheter. Beside the high incidence of RT recordings, for the first time, we observed dual fascicle electrograms with different isolation time for each fascicle, when using the new device.

Purpose
We sought to analyze the rate of visualization of RT recordings and dual fascicle electrograms in our first series of patients with the third generation cryoballoon device.

Methods
All consecutive patients having undergone CB ablation using the third generation technology were analyzed. Procedures were performed under conscious sedation. A single transeptal puncture was preformed guided by intracardial ultrasound and a 28 mm cryoballoon was used. A single 180 seconds freeze strategy was employed.

Results
A total of 80 consecutive patients (77.5% male, 60.3 ± 10.8 years) were evaluated. Real-time recordings were detected in 275 of 320 PVs (85.9%). Specifically, RT recordings could be visualized in 68 left superior PVs (85%), 69 left inferior PVs (86.2%), 73 right superior PVs (91.2%), and 65 right inferior PVs (81.2%). Furthermore, in 14 of 320 PVs (4.3%) two different fascicles electrograms were detected. A distinctive isolation time for each fascicle could be observed both in sinus rhythm and in atrial fibrillation (Picture). Most commonly, dual fascicles were observed in left superior PV (7.5%) and right inferior PV (6.3%). In the rest of the veins this phenomenon was not so frequent. In 2.5% of right superior PV and in only 1.2% of left inferior PV dual fascicles could be observed.

Conclusion
The rate of visualization of RT recordings is significantly high during third generation CB ablation. Real-time recordings can be visualized in 85.9% of veins with this novel cryoballoon. Furthermore, for the first time, isolation of two different fascicles during a single cryoballoon lesion could be observed. Other that more proximal mapping catheter position, there is second possible explanation for the visualization of dual fascicles with this novel balloon. Shorter tip could result with poorer cryoballoon stability and weaker contact with the atrium wall, hence non-uniform freezing and isolation of different fascicles in different times.
Abstract Figure.
P451Optimizing the EP lab workflow in atrial fibrillation ablation - The use of Z stitch for groin access closure
Authors: Velagic V , Prepolec I , Pasara V , Pezo-Nikolic B , Puljevic M , Matasic R , Krpan M , Lovric-Bencic M , Puljevic D , Milicic D 
Published: June 2020

Abstract

Introduction
As catheter ablation became the standard therapy for atrial fibrillation (AF), the number of AF procedures has risen exponentially. Therefore, workflow optimization is crucial in order to meet the rising demands for EP interventions. Recently, instead of standard groin compression we have started using the "Z stitch" for introducers’ removal. This novel method does not necessitate protamine administration and often lengthy manual compression.

Purpose
We aim to demonstrate utilization of "Z stitch" for groin access closure in cryoballoon (CB) ablation and its impact on EP lab workflow.

Methods
We have analyzed all patients having undergone CB ablation utilizing the "Z stitch" (Z group) and the last 50 consecutive CB patients who received standard groin compression (non-Z group). Procedures were performed under conscious sedation. Both femoral veins were punctured and a single introducer was placed in each vein. A single transeptal puncture was preformed guided by intracardial ultrasound and a 28 mm cryoballoon was used. A single 180 seconds freeze strategy was employed.
In the past, protamine was slowly administered after ablation and at least 15 minute manual groin compression was applied until no visual bleeding could be detected. Elastic bandage was placed around both groins. Later on, the "Z stitch" was used around both introducers without the need for protamine administration, manual compression and bandage placement (Picture). The stitches were removed next morning.

Results
A total of 100 consecutive patients (79% male, 61.2 ± 10.6 years old) were evaluated, 50 in both groups. There was no difference in the mean procedure duration ("skin to skin") between two groups. However, a total lab time was significantly longer in non-Z group. There was no differences in complication rates, which consisted solely of phrenic nerve palsy and groin complications. There was no AV fistula or pseudoaneurysms detected in our cohort (Table).

Conclusion
Utilization of Z stitches for introduces’ removal seems safe and effective way to achieve hemostasis after cryoballoon ablation. It abolishes the need for protamine administration which can cause serious advert events. Manual compression is no longer required. Consequently, EP lab workflow is improved, since the total lab time utilization per patient is significantly shortened.
Results non-Z group Z group p Procedure duration (min) 69.4 ± 20.4 73.4 ± 24.8 0.380 Lab time (min) 129.9 ± 35.3 109.1 ± 30.6 0.002 Complications (N) 5 (2 hematoma) 4 (2 hematoma) NS
Abstract Figure. Z stich
741Pharmacological inhibition of the acetylcholine-regulated potassium channel (IK,ACh) prevents atrial arrhythmogenic changes in a rat model for obstructive sleep apnea
Authors: Linz B , Rombouts K , Thostrup A H , Hohl M , Wirth K , Linz D , Jespersen T 
Published: June 2020

Abstract

Background
In obstructive sleep apnea (OSA), intermittent hypoxemia and intrathoracic pressure fluctuations may increase vagal tone, resulting in an increased acetylcholine-regulated potassium current (IK,ACh). Here we elucidated acute atrial electrophysiological effects of obstructive respiratory events simulated by intermittent negative upper airway pressure (INAP) and the role of atrial IKACh activation.

Methods
In sedated spontaneously breathing rats (2% isoflurane), either IK,ACh-inhibitor (XAF-1407: 1mg/kg) or a buffer-based vehicle was perfused (Control). INAP was applied non-invasively by a negative pressure device 14 times throughout 70 minutes. Simulated apneas were maintained for one minute with a four minute resting period. Atrial effective refractory period (AERP), inducible atrial fibrillation (AF)-durations and atrial activation time were acquired by a programmed atrial pacing protocol before, during and after applied INAP throughout the study.

Results
During single INAP applications atrial activation times prolonged transiently in both groups (Control: INAP vs. pre-INAP p = 0.034; XAF-1407: INAP vs. pre-INAP p = 0.039). In control-rats, seventy minutes of repetitive INAP prolonged P-wave duration (+10.8 ± 2.7% vs. baseline, p = 0.008) and decreased AERP by 14.6 ± 3.1% (vs. baseline p = 0.001). AERP shortening correlated with the cumulative pressure applied per body weight (Pearson r= -0.773; p= 0.025). XAF-1407 could prevent P-wave prolongation and AERP shortening. Inducible AF-durations (CTR 0.94 ± 0.34s vs. XAF-1407 0.1 ± 0.09s p = 0.049) were shorter in XAF-1407 treated rats. Drops in oxygen saturation or applied INAP were comparable in control and XAF-1407 rats.

Conclusion
Short-term simulated OSA is associated with AF-related arrhythmogenic changes, which could be prevented by pharmacological IK,ACh inhibition. Moreover, the cumulative negative airway pressure applied determined aERP shortening and may represent a target for OSA treatment. These findings have important implications for the antiarrhythmic management of AF patients with OSA.
P1056Left atrial and left atrial appendage ejection fraction assessed by preprocedural cardiac CT are useful parameters for predicting the outcome of pulmonary vein isolation
Authors: Rezar R , Kaufmann R , Strohmer B , Wernly B , Lichtenauer M , Hitzl W , Hergan K , Granitz M 
Published: June 2020

Abstract

Introduction
Pulmonary vein isolation (PVI) is an effective but complex treatment option for atrial fibrillation (AF). Therefore preprocedural outcome prediction is of special interest. Left atrial volume (LAVmax) is a commonly used predictor for recurring arrhythmia. Several studies have investigated different parameters for the prediction of sustained rhythm control. We hypothesized that left atrial and left atrial appendage ejection fraction (LAEF & LAAEF) assessed by high-resolution CT-imaging are even more sensitive predictors of the outcome of PVI than LAVmax.

Methods
All patients who underwent PVI between 2015 and 2018 with available preinterventional cardiac CT were included in this retrospective study and separated into 2 groups: Group A comprises all patients with sinus rhythm (SR) at follow-up and group B all patients in whom recurrence of AF was observed. Volumetric analysis of the left atrium was performed in ventricular systole (30%-Phase of the cardiac cycle) and diastole (0%-Phase). Obtained data were used to calculate left atrial and left appendage ejection fractions (LAEF & LAAEF). Success of pulmonary vein isolation was defined as clinical freedom of symptomatic AF together with sinus rhythm on the available Holter-ECG recordings during follow-up examinations. Uni- and multivariate logistic regression models and NAMS RMLE tests were used to compare LAVmax to these functional parameters.

Results
In total 152 patients with symptomatic paroxsymal or persistent AF underwent PVI at our hospital from 2015 to 2018. Due to inconsistencies in archiving in our PACS-system, 98 patients had to be excluded from analysis. Four patients were excluded due to motion artifacts. 50 patients were included in the final study (41 patients without and 9 patients with recurring AF on average 254 days after ablation). Significant differences in means were found for all assessed parameters. LAEF (accuracy 94%, sensitivity 67%) and LAAEF (accuracy 90%, sensitivity 67%) had a higher sensitivity than LAVmax (accuracy 86%, sensitivity 33%), though not significant in this study population (p = 0.18). LAVmax and LAEF in combination improved sensitivity significantly from 33% to 78% (p = 0.046). Measurements on cardiac-CT showed an excellent interobserver-reliability.

Conclusion
Reduced LAEF and LAAEF were found to be significant predictors of the outcome of PVI. Furthermore we found a trend that these functional parameters might be more sensitive than LAVmax. Thus we propose that left atrial function, assessed with preprocedural cardiac CT, offers important prognostic information for successful PVI.
Abstract Figure. Surface rendering of LA and LAA
P1028Incidence and location of residual gaps identified by a high-density grid-style mapping catheter after PVI is confirmed by pacing the ablation lines
Authors: Giuggia M , Volpicelli M , Bottoni N , Gora P , Mantica M 
Published: June 2020

Abstract

Background
Durable pulmonary vein isolation (PVI) is critical to the clinical success of ablation for treatment of atrial fibrillation (AF). Pacing along the ablation line (often using the ablation catheter), is one technique that is commonly used for confirmation of PVI. While this technique is common in practice, it has not been systematically evaluated against other methods for confirming PVI. A high-density grid-style mapping catheter (HD Grid) enabling simultaneous recording of adjacent bipolar EGMs in two directions (HD Wave) is now available in multiple geographies. The sensitivity of this technology for periprocedural identification of gaps in PVI lines has not previously been compared to the technique of pacing the ablation lines.

Purpose
To assess the utility of a high-density grid-style catheter for confirming PVI, and to evaluate sensitivity for identification of gaps relative to a technique of pacing the ablation lines.

Methods
Self-reported procedural data was prospectively collected in atrial fibrillation ablation procedures. Cases in which pulmonary vein isolation was confirmed by pacing the ablation line and subsequently assessed with HD Grid were selected for analysis. Techniques for PVI confirmation were analyzed and the incidence and location of residual gaps following PVI confirmation via pacing was quantified.

Results
A total of 22 AF ablation procedures (age 60.1 ± 9.0 years, LVEF 59.3 ± 5.7%, CHADS 1.5 ± 1.4, hypertension 45.5%) across 5 centers in Italy and the United States were analyzed. De novo and repeat ablations represented 72.7% and 22.7% of cases, respectively (4.5% not reported). PVI was confirmed by pacing along the ablation line with an average output of 8.8 ± 1.9mV and pulse width of 2.2 ± 0.7ms (10mv at 2ms utilized in 59.1%). Subsequent PVI assessment was performed with HD Grid using the HD Wave configuration in all cases. PVI confirmation techniques included exit block confirmation (90.9%), voltage mapping (59.1%), loss of pace capture along ablation lines (40.9%), entrance block confirmation (18.2%), and activation mapping (4.5%); note: total exceeds 100% as more than one technique may be employed in a single case. The HD Grid identified a total of 30 gaps in 15 (68.2%) patients, which were initially missed by pacing along the ablation lines. No adenosine or isoproterenol use was documented in any case.
Conclusion(s): Use of the HD Grid appears to increase substantially, the sensitivity for identifying gaps in PVI lesion sets relative to a technique of pacing the ablation line. Limitations of this analysis include small sample size and workflows which consistently assessed PVI with the HD grid following confirmation of isolation by pacing the ablation lines. Despite these limitations, the high prevalence of residual gaps is quite provocative and may warrant additional study.
Abstract Figure.
P1023Comparison of gap identification using three technologies for confirmation of pulmonary vein isolation
Authors: Porterfield C , Wystrach A , Rossi P , Rillo M , Sebag F , Dorszewski A , Gora P , Nilsson K 
Published: June 2020

Abstract

Background
Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Tools and techniques used for confirmation of PVI vary greatly, and it is unclear whether the use of any particular combination of tools and techniques provides greater sensitivity for identifying gaps periprocedurally. A high-density mapping catheter enabling simultaneous recording of adjacent bipolar EGMs in two directions is now available in multiple geographies, and it has been suggested that this technology may provide improved sensitivity for gap identification.

Purpose
To identify trends in the incidence of gaps identified in de novo PVI lines using three diagnostic catheter technologies, which may be suggestive of improved sensitivity for gap identification.

Methods
Self-reported procedural data was prospectively collected in de novo atrial fibrillation ablation cases utilizing one of three technologies to confirm PVI: 10-pole circular mapping catheter (CMC10), 20-pole circular mapping catheter (CMC20), and Advisor HD Grid catheter (HD Grid). Techniques for PVI confirmation were analyzed for each group, and the incidence and location of gaps identified by each technology was quantified.

Results
Data was collected in 99 cases across 11 centers in Europe and the United States. PVI was confirmed via entrance and/or exit block in all cases. CMC10 was utilized in 30 cases, CMC20 in 36, and HD Grid in 33. Use of adenosine varied across groups (CMC10: 6.7%; CMC20: 86.1%; HD Grid: 41.7%), as did application of a waiting period (CMC10: 96.7%; CMC20: 2.8%; HD Grid: 11.1%). Gaps were identified in in 36.7%, 38.9%, and 81.8% of cases using CMC10, CMC20, and HD Grid, respectively. HD Grid identified significantly more gaps than the other two technologies (p = 0.015), identifying an average of 49.0% and 139.1% more gaps per patient than CMC20 and CMC10, respectively (HD Grid: 2.15/patient; CMC20: 1.44/patient; CMC10: 0.9/patient). The location and incidence of gaps identified by each technology is shown in Figure 1.

Conclusions
Significantly more gaps were identified by the Advisor HD Grid catheter, as compared to a 10-pole or 20-pole circular mapping catheter. While this does not represent a direct comparison of the sensitivity for identification of gaps across these three technologies, and results could be impacted by other factors (e.g., operator, ablation technique, PVI confirmation technique, etc.), the strong trend toward an increased number of gaps identified with the HD Grid is striking. This may warrant further study including direct comparison of gap identification across technologies, and the resulting impact on long-term clinical outcomes when these additional gaps are ablated during the index procedure.
Abstract Figure.
910Noise-related malfunctions in modern ICDs during oncologic radiotherapy: a multicentre, real-time, in-vitro observation
Authors: Di Girolamo E , Appignani M , Marini M , De Filippo P , Leidi C , Di Girolamo F , Delana A , Barbareschi A , Andreoli S , Genovesi D , Falco M D 
Published: June 2020

Abstract

Funding Acknowledgements
None

Background
Direct photon exposure of implantable cardioverter-defibrillators (ICDs) during radiotherapy is still considered not recommended, or even unsafe, by manufacturers and guidelines. The effects of photon beams on ICDs are unpredictable, depending on multiple factors, and electromagnetic interferences (EMIs) may present during exposure.

Purpose
To evaluate transient ICD malfunctions by direct exposure to doses up to 10 Gy during low-energy radiotherapy, 36 contemporary wireless-enabled ICDs, with at least 4 months to elective replacement indicator (E.R.I.) were evaluated in a realtime in-vitro session.

Methods
All ICDs had baseline interrogation. Single chamber devices were programmed in the VVI/40 mode and dual or triple chamber devices were programmed in the DDD/40 mode. Rate response function and antitachycardia therapies were disabled, with the ventricular tachycardia (VT)/ventricular fibrillation (VF) detection windows still working. A centering computed tomography was performed to build the corresponding treatment plan and the ICDs were blinded randomized to receive either 2, 5 or 10 Gy exposure by a low photon-energy linear accelerator (6MV) in a homemade water phantom (600 MU/min). The effective dose received by the ICDs was randomly assessed by an in-vivo dosimetry. During radiotherapy course, the devices were observed in a real-time session using manufacturer specific programmer, and ICD function (pacing, sensing, programmed parameters, detection) was recorder by the video camera in the bunker throughout the entire photon exposure. All ICDs had an interrogation session immediately after exposure.

Results
During radiotherapy course, almost all ICDs (90.9%) recorded major or minor transient EMIs. On detail, 16 ICDs (44.4%) reported EMI-related atrial and/or ventricular oversensing, with base-rate-pacing inhibition and VT/VF detection. 16 ICDs (44.4%) recorded not clinically relevant minor EMIs, and no detections were observed. Only 4 ICDs (11.2%) reported neither transient malfunction nor minor EMIs, withstanding direct radiation exposure. At immediate post-exposure interrogation, the ICDs that recorded major real-time malfunctions had VT/VF detections stored in the device memory. In none of the ICDs spontaneous changes in parameter settings were reported. EMI-related malfunctions occurred regardless of either 2, 5 or 10 Gy photon beam exposure.

Conclusions
Transient EMIs were observed in most of the contemporary ICDs. To avoid potentially life-threatening ICD malfunctions such as pacing inhibition or inappropriate shock delivery, magnet application on the pocket site or reprogramming in the asynchronous mode are still suggested in ICD patients ongoing even low energy radiotherapy exposure.
P1409Effectiveness of atrial fibrillation ablation using a contact force stability module with contact force or non-contact force catheter
Authors: Khaykin Y , Alipour P , Azizi Z , Avoulov A , Jansen C , Donegan S , Morris S , Nath S , Tamjidi S , Varah N , Pantano A , Verma A , Weaver B , Hunter T D 
Published: June 2020

Abstract

Funding Acknowledgements
This study was funded by Biosense Webster, Inc.

Background
Catheter ablation is a mainstream treatment option for atrial fibrillation (AF). Recently, contact force (CF) enabled ablation catheters and a stability module were developed to allow for real-time CF sensing and improvement of catheter-tissue stability, which is important for achieving an optimal clinical outcome. We assessed the relative effectiveness of these new technologies, as well as the optimal CF stability parameters, in a real-world setting.

Purpose
To compare the clinical effectiveness of AF ablations performed with a CF catheter using location stability settings of 2.5 mm maximum distance for 12 s minimum (2.5/12) vs. a non-CF catheter with settings of 3 mm for 7 s (3/7).

Methods
Within 1/14–4/18, 176 de novo AF ablations using either a CF catheter with stability settings of 2.5/12 (n = 92, 5/16–4/18) or a non-CF catheter with stability settings of 3/7 (n = 84, 1/14–3/14) were performed by a single operator at a Canadian medical center. Patients routinely wore 48 hour Holter monitors every three months through the first year. The primary measures of effectiveness were Kaplan-Meier (KM) survival estimates of freedom from AF/atrial tachycardia (AT)/atrial flutter (AFL) recurrence after a 3-month blanking period and reablation.

Results
The CF group was 62.9 ± 10.0 years old, 57.6% male, and 66.3% paroxysmal (PAF). The non-CF group was 61.6 ± 9.9 years old, 63.1% male, and 76.2% PAF. Procedural complications consisted of a single vascular access complication in the non-CF group. The 12-month estimate of freedom from AF/AT/AFL recurrence was 79.4% in the CF group vs. 64.8% in the non-CF group (p = 0.058 for difference in survival over time). 12-month freedom from reablation was 90.4% in the CF group vs. 70.5% in the non-CF group (p = 0.002).

Conclusion
CF ablation with more stringent stability settings of 2.5/12 was more effective than non-CF ablation with stability settings of 3/7, likely attributable to the CF catheter enabling visualization of catheter-tissue contact and the stability module facilitating maintenance of CF stability during ablation.
Abstract Figure.