bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effectiveness of various radiofrequency ablation catheters in the treatment of typical atrial flutter
Authors: Gorantla A , Alsaiqali M , Sivakumar S , Francois J , Freytes-Santiago L , Jallad A , Budzikowski A 
Published: October 2022

Abstract

Introduction
Although ablation of typical atrial flutter (AFL) can be easily achieved with radiofrequency energy (RF), there are no studies that compare effectiveness of different ablation catheters. Our study aimed to compare the effectiveness of various types of ablation catheters in the treatment of AFL.

Methods
We analysed patients with AFL who underwent RF ablation by a single operator at our institution. Successful ablation was evidenced by presence of bidirectional conduction block (trans-isthmus conduction time ≥130 ms, or doubling of baseline conduction time, or presence of double potentials ≥90ms). Logistic regression was used to compare success rate and linear regression to compare lesion time.

Results
Out of the 222 patients, only 6 patients did not meet success criteria (2.7%). Catheters used were 8 mm tip in 16 patients, internally irrigated (Chili II Boston Scientific) in 47 patients, externally irrigated (non-force sensing) catheters (CoolPath, Abbott) in 40 patients. Externally irrigated force sensing catheter (Tacticath, Abbott) was used with &gt;10 gm of force and (LPLD) setting (30W-45°C-60 sec) in 50 patients, and high-power short duration (HPSD) setting (50W-43°C −12 sec,) in 70 patients. No complications were encountered. Catheter type had no statistically significant association with ablation success. In terms of lesion time, HPSD catheter statistically significantly shortened lesion time by 758.3s, [CI −1128.29, −388.35s] followed by LPLD by 419.0s [CI −808.49, −29.47s]. Table 1 shows the lesion time difference for the catheters used as compared with 8 mm tip.

Conclusions
Typical atrial flutter radiofrequency ablation procedure had a high success rate, not influenced by type of ablation catheter. Contact force ablation catheter on HPSD is associated with shorter total lesion time.

Funding Acknowledgement
Type of funding sources: None.
Prognostic impact of cavotricuspid isthmus ablation for typical atrial flutter in patients with heart failure and reduced ejection fraction
Authors: Boxhammer E , Bellamine M , Szendey I , Kletzer J , Foresti M , Kraus J , Danmayr F , Topf A , Jirak P , Bonsels M , Lichtenauer M , Hoppe U C , Strohmer B , Motloch L J , Larbig R 
Published: October 2022

Abstract

Background
The CASTLE-AF trial in 2018, showed that pulmonary vein isolation provides a survival benefit and a reduced hospitalization rate in patients with heart failure and concomitant atrial fibrillation. Typical atrial flutter (AFL) can also induce heart failure (tachymyopathy) or, if cardiomyopathy of other origin is prevalent, can further worsen it. Cavotricuspid isthmus ablation (CTI) is a simple, invasive electrophysiological procedure that can effectively treat AFL. Prognostic data on the impact of CTI in patients with heart failure and reduced ejection fraction (HFrEF) is lacking.

Purpose
This study focused on the analysis of the clinical impact of CTI vs. medical therapy in patients with HFrEF.

Methods
The present retrospective, international, multi-center study included 104 patients &lt;85 years with AFL and heart failure (LVEF &lt;50%). 64 patients underwent an electrophysiological study with successful CTI (ablation group), whereas 40 patients received medical therapy alone with frequency or rhythm control and guideline-compliant heart failure therapy (medical therapy group). Patients were followed up for a total of 2 years, with particular emphasis on recording the change in LVEF over time. The primary endpoints were cardiovascular mortality and hospitalization for cardiac causes.

Results
Patients after CTI showed a significant increase in LVEF after 1 year (with the exception of valvular cardiomyopathy). The optimization of LVEF was also reflected in the Kaplan-Meier curves, as the ablation group had a significantly lower 2-year, cardiovascular mortality (p&lt;0.001). The hospitalization rate for cardiac causes in the overall cohort showed a tendency towards reduced hospitalizations (p=0.072). Elderly patients also benefited from CTI in this study. Specifically, Patients ≥70 years of age showed a significantly lower re-hospialization rate after CTI (p=0.043) as well as a significantly reduced mortality after 2 years (p=0.012).

Conclusions
CTI in patients with AFL and HFrEF was associated with significant optimization of LVEF and lower rates of hospitalization and mortality after 2 years. Patient age should not be a primary exclusion criterion for CTI because in this study, patients ≥70 years also benefited significantly from intervention in terms of mortality and hospitalization.

Funding Acknowledgement
Type of funding sources: None.
Outcomes of catheter ablation for typical atrioventricular nodal reentrant tachycardia with low power energy
Authors: Kim M , Oh J K , Yoon Y H , Park H W , Roh J H , Lee J H 
Published: October 2022

Abstract

Background
Atrioventricular nodal reentrant tachycardia (AVNRT) is most common supraventricular tachycardia with acceptable outcome of catheter ablation. However, the serious complication of atrioventricular block (AVB) can occur and affects 0.2% to 2.3% of patients during or after procedures.

Purpose
We hypothesized that slow pathway ablation with 20 watt (W) energy would facilitate acceptable clinical outcomes and low procedure related AVB needed permanent pacemaker.

Methods
Prospective single center trial was performed. Slow pathway ablation was performed in 212 patients (mean age 56.5±18.4 years, 131 women) from January 2017 to May 2020. Twenty watt energy was delivered at the posterior region of the triangle of Koch until accelerated junctional rhythm was obtained.

Results
A total of 212 patients who underwent ablation for typical AVNRT were included. The acute success rate, the mean radiofrequency pulses applied per patient were 98.1% and 8.6±6.6, respectively. Transient AVB occurred in 5 patients (2.4%) and no permanent AVB requiring permanent pacemaker implantation occurred. Those who failed 20 W ablation were younger (success group age vs failed group age 58.2±17.4 vs 31.8±17.9 years, p=0.005) and had a faster heart rate just before slow pathway ablation (success group heart rate vs failed group heart rate 69.2±11.3 vs 76.8±5.6 bpm, p=0.59). The recurrence rate of 20 W ablation was 2.6% and the follow-up period was 18.3±4.1 months.

Conclusion
The low power approach for slow pathway ablation is highly effective and safe. If the heart rate just before ablation is lesser than 70 bpm, slow pathway ablation with 20 W energy could be considered. Further well-designed large-randomized studies are needed to define the role and effect of catheter ablation for typical AVNRT with low power energy.

Funding Acknowledgement
Type of funding sources: None.
Pulsed field ablation for atrial fibrillation: acute procedural efficacy and safety of an initial German multicenter experience
Authors: Gunawardene M A , Lemoine M , Deneke T , Wakili R , Steven D , Schaeffer B , Rillig A , Nentwich K , Siebermair J , Filipovic K , Simu G , Riesinger L , Sultan A , Willems S , Metzner A 
Published: October 2022

Abstract

Background
Pulsed field ablation (PFA) is a novel non-thermal energy source to conduct catheter ablation of atrial fibrillation (AF). However, real-world multi-center data regarding acute procedural efficacy and safety is sparse.

Purpose
To study acute procedural success and safety in patients undergoing PFA for catheter ablation of AF in a multicenter registry.

Methods
Consecutive paroxysmal and persistent AF patients undergoing PFA-based catheter ablation using a multispline catheter were enrolled. The cohort included first and repeat ablation procedures. Procedural parameters, acute success and in-hospital safety were evaluated. A follow-up of all patients was conducted.

Results
Five German centers enrolled a total of 154 patients undergoing PFA in this study. Mean age was 68±12 years, median CHA2DS2-VASc Score was 3 (Q1-Q3: 2–4).
Patients suffered from paroxysmal AF (n=55; 36%), persistent AF (n=93; 60%) and consecutive atrial tachycardias (AT) due to previous CA (n=6; 4%).
The median left atrial (LA) PFA and total procedure times were 33 (Q1-Q3: 24–53) and 90 (Q1-Q3: 73–116) minutes, respectively. Mean LA PFA fluoroscopy and total fluoroscopy times were 12.1±5.5 and 20.2±8.7 minutes. Of all 154 procedures, 130 (84%) were index ablation procedures with isolation of pulmonary veins (PVI) only and 24 (16%) were repeat procedures (including re-PVI and ablation of consecutive AT).
Acute PV reconnection following primary PVI and the initial set of PFA-applications was found in 20/130 (15%) patients, necessitating additional PFA ablation. Finally, successful PFA-guided PVI was achieved in all patients.
Additional PFA lesion sets (including LA posterior wall isolation, anterior ablation, mitral isthmus ablation) were applied in 17/154 (11%) patients.
Complications occurred in a total of 6/154 (3.8%) patients (including three groin site complications, two pericardial tamponades, one transient coronary spasm without sequela). The follow up data is still being assessed and will be provided by the time of the ESC 2022 meeting.

Conclusion
PFA performed in patients with atrial fibrillation demonstrates high acute procedural success rates and a favorable safety profile in this first real-world multicenter registry.

Funding Acknowledgement
Type of funding sources: None.
Early rapid local impedance drop is associated with acute lesion efficacy during pulmonary vein isolation using a novel contact force sensing catheter
Authors: Perge P , Sallo Z , Petrovic N , Piros K , Nagy K V , Osztheimer I , Merkely B , Geller L , Szegedi N 
Published: October 2022

Abstract

Introduction
The predictive role of adequate local impedance drop in lesion formation using a novel contact force sensing ablation catheter for pulmonary vein isolation was recently described. The purpose of our study was to assess the temporal characteristics of local impedance drop during ablation and its correlation with acute lesion efficacy.

Methods
Point-by-point radiofrequency pulmonary vein isolation was performed in power-controlled mode with 50 W energy setup. The efficacy of applications was determined by pacing along the circular ablation line. The successful lesions were estimated if loss of capture was achieved. Local impedance, contact force and catheter position data of the applications with 5 msec resolution was analysed. The local impedance of successful and unsuccessful applications was compared at baseline and 2, 4, 6, 8, 10 and 12 sec time points, respectively. We characterized the local impedance for each time point with the mean of the 5 impedance value closest in time. The sum of the range of catheter position in x, y and z dimensions was also compared to assess stability during the application.

Results
643 applications were analysed, 559 were successful and 84 were unsuccessful. Mean contact force was lower (p=0.04), while the sum of catheter position range was higher (p&lt;0.001) in unsuccessful applications during ablation, suggesting worse catheter stability. The successful applications were characterized by a higher baseline local impedance (p&lt;0.001), and a larger local impedance drop at the 2, 4, 6, 8 and 10 sec time points (p&lt;0.001, for all). In case of unsuccessful applications, after a moderate but significant drop from baseline to the 2 sec time point (baseline: 153 Ohm vs 2 sec: 145 Ohm, p&lt;0.001) local impedance did not change further over time (2 sec: 145 Ohm vs 12 sec: 143 Ohm; p=0.99). While on the other hand, in case of successful applications, the local impedance further decreased significantly up to the 10 sec timepoint, respectively (baseline: 161 Ohm vs 2 sec: 150 Ohm vs 10 sec: 141 Ohm, p&lt;0.001 for all). The optimal cut-point for the local impedance drop indicating unsuccessful application was &lt;9 Ohms at the 4 second time point [AUC=0.73 (0.67–0.76), p&lt;0.001]. Failing to reach at least 9 Ohm impedance drop at the 4 second time point predicted unsuccessful applications [(p&lt;0.001; OR: 3.82 (2.34–6.25)].

Conclusion
Rapid and enduring drop of the local impedance may predict effective lesion formation, while slightly changing or unchanged local impedance is associated with unsuccessful applications. In case of a moderate local impedance drop during the first 4 seconds of radiofrequency application, it might be reasonable to stop the application and start a new one after catheter repositioning.

Funding Acknowledgement
Type of funding sources: None.
Inflammation begets isolated atrioventricular conduction disturbances in young an observation from indian registry data
Authors: Moukthika K V N , Krishnappa D , Patloori Sirish Chandra S , Bhole C , Deshpande S , Roshan J , Barthur A , Parameshwaran S , Mehta R , Padmanabhan D 
Published: October 2022

Abstract

Background
High grade AV block is less commonly encountered in patients &lt;60 years. The aetiological role of inflammatory conditions is not well studied in this group of patients.

Purpose
To determine the prevalence of myocardial inflammation in young patients presenting with High grade AV block and assess its response to immunosuppression.

Methodology
This is a prospective, registry based, observational study conducted at two centers from Jan 2020 to Dec 2021. Myocardial inflammation was detected using Cardiac PET, and/or histopathological examination. Those with evidence of inflammation were started on graded immunosuppression.

Results
318 patients were enrolled. Mean EF was 55.2±7.0%. Cardiac PET was performed in 87/318 (27.3%). Myocardial inflammation was seen in 57/87 (65%). LV basal septum was most commonly involved. 44/57 (77%) were started on immunosuppressive therapy after excluding indolent tuberculosis.8 patients died during follow-up with all deaths being sudden in nature. 5/44 (11.3%) had reversal of CHB with resolution of cPET findings.

Conclusion
Significant proportion of young patients with High grade AV block have segmental myocardial inflammation. Immunosuppression helps restore AV conduction in some of these patients. Long-term studies are required to assess adverse impact of inflammation on cardiac contractile function.

Funding Acknowledgement
Type of funding sources: None.
Opposite evolution on voltage and thickness from paroxysmal to persistent AF
Authors: Silva Garcia E , Banez V , Gonzalez M , Puche J E , Gomez A , Cano L , Fernandez R , Fernandez M , Fernandez-Armenta J 
Published: October 2022

Abstract

Background
There is a controversy about correlation between voltage and thickness in the atrial myocardium and their evolution from paroxysmal to persistent atrial fibrillation (AF).

Purpose
This is an observational study to compare voltage and thickness of different areas on the left atrium in paroxysmal and persistent atrial fibrillation.

Methods
Twenty-one patients underwent atrial fibrillation ablation. Points with electrical information from an electroanatiomical map in sinus rhythym were acquiered during the ablation procedure covering the whole atrial surface. CT was acquired in all patients before the procedure and endo- and epicardium from the atrium was segmented for the atrial thickness calculation. All the points from the electromecanical map were projected on the thickness map to have both information on the same location. 3D atrium was segmented in 5 areas for the analysis: Lateral, Anterior, Septal, Inferior-Posterior and Superior-Posterior (Figure 1). Voltage and thickness values among different areas and between AF type were compared.

Results
11 paroxysmal and 10 persistent AF patients were analyzed acquiring 452±207 points per patient and 1897±750 points per area. There was no linear correlation between voltage and thickness comparing all the patients nor among different areas nor between AF type (R&lt;0.2 in all cases).
Regarding paroxysmal AF patients, septum showed significatly lower voltage compared with the other segments, posterior, lateral, anterior and roof (1.3±1.4, 2±1.8, 2±1.6, 1.7±1.5, 2±1.6, P&lt;0.001). Posterior segment showed the highest voltage. The thickness analysis showed the septum segment as thinner segment and lateral as thicker segment (1.3±1.5,1.7±0.8, P&lt;0.001) (Figure 2).
Regarding persisten AF patients: septum showed significatly lower voltage compared with the other segments, posterior, lateral, anterior and roof who shows higher voltage (1±0.8*, 1.5±1.2, 1.9±1.7, 1.5±1.4, 2±1.6) (Figure 2). The thickness analysis showed the anterior segment as thinner segment and lateral as the thickest segment (1.6±0.8, 1.9±0.9 (P&lt;0.001), different like on paroxysmal AF population.
Comparing voltage and thicknes between paroxysmal and persistent AF, all the segments on persistent population showed lower voltage values, with significant differences on septal, posterior and anterior walls (1±0.8 vs 1.3±1.4, 1.5±1.2 vs 2±1.8, 1.5±1.4 vs 1.7±1.5, P&lt;0.001). On the other hand, all segments on persistent population showed statisticaly signignificant thicker myocardium in camparison with paroxysmal population (Figure 2).

Conclusions
According to our findings, there is no linear correlation between voltage and thickness. Persistent AF atria show thicker walls but with lower voltages in comparison with paroxysmal AF atria.

Funding Acknowledgement
Type of funding sources: None.
Dapagliflozin but not empagliflozin prevents atrial fibrillation in an experimental whole-heart model
Authors: Frommeyer G , Uphoff J , Wolfes J , Eckardt L , Ellermann C 
Published: October 2022

Abstract

Background
The SGLT2 inhibitors dapagliflozin and empagliflozin have an evolving role in heart failure therapy. Observational data suggest a lower risk of atrial fibrillation (AF) for patients on SGLT2 inhibitors. So far, it is unclear whether this is related to a direct antiarrhythmic potential of SGLT2 inhibitors or just a marker of improved heart function. Experimental data on the impact of SGTL2 inhibitors on atrial electrophysiology is scarce.

Purpose
This study aimed at evaluating the effects of the two SGLT2 inhibitors dapagliflozin and empagliflozin on atrial electrophysiology.

Methods
25 rabbit hearts were explanted and retrogradely perfused employing the Langendorff-setup. Two catheters were placed on both atria to record monophasic action potentials. Hearts were paced at three different cycle lengths (350ms, 250ms, 150ms), thereby obtaining cycle-length dependent atrial action potential durations (aAPD90) and effective refractory periods (aERP). Atrial post-repolarization (aPRR) refractoriness was determined by the difference between aERP and aAPD90. AF was induced in the presence of acetylcholine (ACh, 1μM) and isoproterenol (Iso, 1μM). Thereafter, hearts were treated with dapagliflozin (n=13, 3 μM) or empagliflozin (n=12, 3 μM).

Results
Ach/Iso abbreviated aAPD90, aERP and prolonged aPRR in both groups (dapagliflozin group: aAPD90: −49 ms, p&lt;0.01; aERP: −33 ms, p&lt;0.01; aPRR: +18 ms, p=0.06; empagliflozin group: aAPD90: −40 ms, p&lt;0.01; aERP: −25 ms, p&lt;0.05; aPRR: +18 ms, p=0.05). Further treatment with dapagliflozin increased aAPD90 (+13 ms, p&lt;0.01), aERP (+34 ms, p&lt;0.05) and aPRR (+6 ms, p=ns). Additional administration of empagliflozin had no significant effect on aAPD90 (−8 ms, p=ns), aERP (−1 ms, p=ns) or aPRR (+9 ms, p=ns). Vulnerability to AF was assessed by a standardized protocol consisting of several trains of burst pacing. Ach/Iso increased the vulnerability to AF episodes in both groups (dapagliflozin group: 71 episodes vs. 1 under baseline conditions, p&lt;0.01; empagliflozin group: 27 episodes vs. 2 under baseline conditions, p=0.08). Additional perfusion of dapagliflozin significantly reduced the occurrence of AF (to 30 episodes, p&lt;0.05) while additional empagliflozin treatment had no significant antiarrhythmic effect (32 episodes, p=ns).

Conclusion
Dapagliflozin and empagliflozin had opposing effects on atrial electrophysiology. Dapagliflozin prolonged aAPD90 and aERP, thereby preventing AF. In contrast, empagliflozin did not change aAPD90 or aERP, resulting in no antiarrhythmic effect. Our findings hint at a potential antiarrhythmic benefit of dapagliflozin.

Funding Acknowledgement
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Hans and Gertie Fischer-Foundation (to C.E.)
Sodium-glucose cotransporter 2 inhibitors not only suppress recurrence after atrial fibrillation ablation but also cause atrial reverse remodeling
Authors: Mine T , Kitagaki R , Fukuhara E , Ishihara M 
Published: October 2022

Abstract

Background
Sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown fewer heart failure (HF) hospitalization and cardiovascular death in patients with type-2 diabetes mellitus (DM). Atrial fibrillation (AF) is associated with both HF and DM, and we reported SGLT2 suppressed AF recurrence after catheter ablation (CA) than dipeptidyl peptidase-4 (DPP4) inhibitor.

Purpose
We evaluated whether SGLT2 itself induces atrial reverse remodeling.

Methods
This is a sub-analysis of a prospective randomized controlled open-label clinical study for comparing the suppressive effect of SGLT2 inhibitor with DPP4 inhibitor on AF recurrence after CA. Eighty AF patients with type-2 DM were randomized to Tofogliflozin group or Anagliptin group with a computer-generated random sequence, which was stratified by left atrial diameter and AF type at screening. Primary outcome is AF recurrence at 12 months after CA, and secondary outcomes include the echocardiographic findings.

Results
70 patients (70.3±8.1 years, 58 male, 30 paroxysmal AF, 38 Tofogliflozin) were analyzed. Recurrent AF was detected in 24 patients (34.3%), and the AF recurrence ratio was higher in the Anagliptin group than the Tofogliflozin group. In 46 patients without AF recurrence (17 Anagliptin, 29 Tofogliflozin), LAVI has shrunk in 12 months compared to the baseline (42.8±11.9 to 36.6±11.2ml/m2) and the reduction of LAVI was larger in Tofogliflozin group than Anagliptin group (−8.6±2.0ml/m2 vs. −2.0±2.6ml/m2, P=0.0471).

Conclusion
Tofogliflozin not only suppressed AF recurrence after CA but also caused atrial reverse remodeling than Anagliptin in type-2 DM patients.

Funding Acknowledgement
Type of funding sources: None.