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Background: The automated NavX Ensite Precision latency-map (LM) algorithm aims to identify atrial tachycardia (AT) mechanisms. However, data on a direct comparison of this algorithm with conventional mapping are scarce. Methods: Patients scheduled for AT ablation were randomized to mapping with the LM- algorithm (LM group) or to conventional mapping (conventional only group: ConvO), using entrainment and local activation mapping techniques. Several outcomes were exploratively analyzed. Primary endpoint was intraprocedural AT Termination. If AT termination with only automated 3D-Mapping failed, additional conventional methods were applied (conversion). Results: A total of 63 patients (mean 67 years, 34 % female) were enrolled. In the LM group (n = 31), the correct AT mechanism was identified in 14 patients (45 %) using the algorithm alone compared to 30 patients (94 %) with conventional methods. Time to termination of the first AT was not different between groups (LM group 34 ± 20 vs. ConvO 43.1 ± 28.3 min; p = 0.2). However, when AT termination did not occur with LM algorithm, time to termination prolonged significantly (65 ± 35 min; p = 0.01). After applying conventional methods (conversion), procedural termination rates did not differ between LM group (90 %) vs. ConvO (94 %) (p = 0.3). During a follow-up time of 20 ± 9 months, no differences were observed in clinical outcomes. Conclusion: In this small prospective, randomized study, the use of the LM algorithm alone may lead to AT termination, but less accurate than conventional methods.

Abstract Pulmonary vein stenosis (PVS) after radiofrequency energy‐mediated percutaneous pulmonary vein isolation as a treatment option for atrial fibrillation is a serious complication and the prevalence in historical reports varies between 0% and 42%. Symptoms of PVS are nonspecific and can include general symptoms such as dyspnea, cough, recurrent pneumonia, and chest pain. Pathophysiologically it increases the postcapillary pressure in the pulmonary circuit and may result in pulmonary hypertension (PH). Misdiagnosis and delayed treatment are common. We here report a case of a 59‐year‐old female with a history of pulmonary vein ablation followed by progressive dyspnea (New York Heart Association IV), right heart failure, CPR, and the need for extracorporeal membrane oxygenation (ECMO). Further treatment strategy includes pulmonary vein dilatation and stenting of both the left superior pulmonary vein and left inferior pulmonary vein, as well as balloon dilatation of RIPV under temporary ECMO support. Symptomatic, severe PVS is a rare complication after catheter ablation of atrial fibrillation. PVS can result in life‐threatening complications such as PH with acute right heart failure. Early diagnosis is crucial but challenging. Mechanical cardiopulmonary support by veno‐arterial ECMO for bridging to angioplasty could be a lifesaving option.

Background: Recent animal and human studies have shown antiarrhythmic effects inhibiting inducibility of atrial fibrillation through low-level transcutaneous electrical stimulation at the auricular branch of the vagus nerve (ABVN). Objective: The present study investigated effects of acupuncture at the ABVN on the autonomic cardiac nervous system in humans through analysis of heart rate and heart rate variability (HRV) parameters. Methods: We enrolled 24 healthy male volunteers and compared acupuncture at the ABVN to placebo-acupuncture performed at the Ma-35 point (an acupuncture point used in traditional Chinese medicine to treat pain caused by gonarthrosis). An additional measurement without acupuncture served as control. We analyzed the following heart rate and HRV parameters: standard deviation of normal-to-normal intervals (SDNN), root mean square of successive R-R interval differences (RMSSD), high frequency (HF), low frequency (LF), LF/HF ratio. Results: In comparison to placebo acupuncture, acupuncture at the ABVN led to a significant reduction in heart rate (approximately 4%–6%, P < .05) and an increase in overall HRV demonstrated by SDNN (approximately 19%, P < .05). RMSSD and power spectral density parameters (HF, LF, LF/HF) showed statistical trends (P < .1) induced by auricular acupuncture in favor of vagal tone. No relevant difference was shown between control and placebo group. Conclusion: Acupuncture of the region innervated by the ABVN may activate the parasympathetic nervous system, as suggested by reduction in heart rate and increase in SDNN. However, given the lack of clear significant changes in other HRV parameters, this effect seems modest and its evaluation requires further investigation.

Much of our understanding of the mechanisms of macro re-entrant atrial tachycardia comes from study of cavotricuspid isthmus (CTI) dependent atrial flutter. In the majority of cases, the diagnosis can be made from simple analysis of the surface ECG. Endocardial mapping during tachycardia allows confirmation of the macro re-entrant circuit within the right atrium while, at the same time, permitting curative catheter ablation targeting the critical isthmus of tissue located between the tricuspid annulus and the inferior vena cava. The procedure is short, safe and by demonstration of an electrophysiological endpoint - bidirectional conduction block across the CTI - is associated with an excellent outcome following ablation. It is now fair to say that catheter ablation should be considered as a first line therapy for patients with documented CTI-dependent atrial flutter.

Abstract Introduction  AP localization can be predicted by analyzing the polarity of the delta wave, QRS polarity, and R/S ratio in patients with Wolff–Parkinson–White syndrome. However, the estimation of AP location is limited in patients with concealed pathways during atrioventricular reentrant tachycardias (AVRT). Thus, we analyzed retrograde P-wave polarity during orthodromic AVRT and developed an algorithm to predict the localization of concealed accessory pathways (AP). Methods and Results  A total number of 131 patients with a single AP and inducible orthodromic AVRT were included. The initial 61 patients were analyzed retrospectively for algorithm development, whereas 70 patients were evaluated prospectively. The retrograde P-wave polarity was analyzed by subtracting the superimposing T-wave during orthodromic AVRT using custom-designed software. Four leads of the surface electrocardiogram (ECG) were identified to accurately distinguish AP locations assigned to four different regions around each AV annulus: I, aVR, aVL, and V1. Lead V1 was used to differentiate right (negative or isoelectric) from left (solely positive) APs. Retrograde P-wave in lead I was negative in left posterior APs exclusively and became more positive with an AP location shifting towards right anterior. P-wave polarity in lead aVR demonstrated a shift from a positive polarity from left APs to isoelectric in right APs. The opposite direction (shift from positive to isoelectric) was observed for lead aVL. The subsequently developed algorithm for concealed AP localization using these surface ECG leads demonstrated a high sensitivity, specificity, and positive predictive value particularly for common AP localizations (left posterior and inferior, and right septal) when applied in a prospective fashion. Conclusion  Concealed AP localization can be accurately predicted by the analysis of retrograde P-wave polarity during orthodromic AVRT using the algorithm derived from the presented study. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary vein (PV) isolation for the curative treatment of atrial fibrillation using conventional radiofrequency ablation (RF) catheters with the point by point technique is time consuming and carries a remaining risk for thrombembolic complications.Aims of the Study: Aim of the present in vivo study was to evaluate feasibility and safety of a novel multipolar irrigated ablation catheter designed to create contiguous lesions encircling the PV ostium in a single ablation position.Methods: The entire ablation section (tripolar, length of each electrode 22 mm, interelectrode distance 2 mm, helix radius: 9 and 10 mm) of the 7F RF catheter (Encirclr, Medtronic, MN, USA) was covered by a porous membrane (pore size 30 micron) providing continuous irrigation. The helical formed catheter was used in two different experimental settings. Initially, a thigh muscle preparation has been performed in 7 anesthetized sheep in order to evaluate the development of lesions at different power level (40–80 W) and RF duration (30–90 sec). The ablation catheter was placed at the surface of the thigh muscle in a perpendicular position (0.1 N contact pressure) and perfused with heparinized blood (250 ml/min, 37C°). Irrigation was provided with a flow rate of 10 ml/min. The resulted lesion morphology was evaluated with regard to coagulum or crater formation and lesion depth and diameter. Subsequently in 9 anesthetized sheep intracardiac ablation has been achieved with 50 W and an irrigation flow of 10 ml/min. Transseptal puncture and RF ablations were guided using fluoroscopy and intracardiac echocardiography (ICE, Acuson, USA). Endpoint of the intracardiac RF applications was the reduction of local electrogram amplitude >50%. RF applications were achieved at both atrial appendages and in the orifices of the coronary sinus (CS), the vena cava inferior (VCI) and PV. Following RF ablation all animals were sacrificed and following in vivo staining (2% TTC) macroscopically and histologically investigations of the lesions were performed.Results: At the thigh muscle preparation 57 RF applications have been performed. The lesion depth was homogeneous without gaps between the ablation electrodes. There was a significant increase comparing 30 with 90 sec of RF duration for 40, 50 and 60 W applications respectively: 40 W: 1.1 ± 0.4 vs. 3.6 ± 0.5; 50 W: 1.2 ± 0.3 vs. 4.6 ± 0.4 mm and 60 W: 2.6 ± 0.6 vs. 4.8 ± 0.5 mm. All applications with 80 W (n = 3) had to be terminated due to immediate increase of impedance >150 ω . Late impedance rises (>60 sec) without occurrence of coagulum formation have been observed in 1 out of 4 RF applications with 60 W.A total of 85 RF applications could be achieved intracardiacally in the right atrium (right atrial appendage n = 18, ostium of the coronary sinus n = 12, ostium of the inferior caval vein: n = 12) and in the left atrium (left atrial appendage: n = 15, ostium of the PV: n = 28). ICE guided positioning of the catheter and showed during all applications no coagulum formation at the electrode or impedance rise (>150 Ω). Reduction of local electrograms (>50%) were observed following 48 out 85 (56%) RF applications. The lesions showed a homogeneous depth of 4 ± 2 mm and a width 5 ± 2 mm at the surface. No charring or crater formation could be observed in any of the lesions.Conclusions: In the present in vivo studies it could be demonstrated that long irrigated ablation electrodes induce continuous lesions without the risk of thrombus formation at the electrode. Increase of RF duration from 30 to 90 seconds with power setting of 40–60 W, respectively, created deeper lesions without the risk of thrombus formation. Thus, the helical formed irrigated ablation catheter appears to be appropriate for simplified PV isolation. [ABSTRACT FROM AUTHOR]

Background: Complex ablation for persistent atrial fibrillation (AF) aims to modify the arrhythmogenic substrates to become incapable to perpetuate the arrhythmia. Ablation-associated determinants of atrial tachycardia (AT) rather than AF recurrences are unknown. The aim of the study was to evaluate the association between the type of arrhythmia recurrence and electrophysiological findings during redo procedures. Methods: A total number of 384 consecutive patients with persistent AF underwent complex ablation consisting of PV isolation (PVI), biatrial electrogram-guided ablation, and linear ablation with the desired procedural endpoint of AF termination. Electrophysiological findings during redo procedures and its relation to AR type are the subject of this study. Results: Overall, 177 (46%) patients underwent a second procedure. Patients with AT recurrences had significantly more often persistent PVI (47 vs. 25%; P = 0.002). Moreover, a higher number of recovered PVs were associated with AF recurrence (3 PVs recovered, AF = 16.1% vs. AT = 5.2%; P = 0.02; 4 PVs recovered, AF = 18.5% vs. AT = 6.3%; P = 0.01), regardless of the extent of substrate ablation during the first procedure. Conclusions: Durable PV isolation but not the extent of atrial substrate ablation determines the type of arrhythmia recurrence. Thus, the PVs may represent dominant perpetuators (and not only triggers) of persistent AF even in the presence of a significantly modified atrial substrate. [ABSTRACT FROM AUTHOR]

The article focuses on the atrial fibrillation (AF) mapping technology called RETRO-Mapping, it analyzes activation patterns during AF using a multipolar catheter. It reports that the wavefront activation directions and demonstrates that activation patterns can predict subsequent wavefront patterns, providing insights into the complexities of AF activation patterns and potentially improving treatment approaches.

This document is a thank you message from the journal "Thoracic & Cardiovascular Surgeon" to the 157 reviewers who contributed to the journal in 2023. The reviewers were commended for their voluntary contributions and dedication to maintaining the high standards of the peer review process. The document also expressed gratitude to the members of the cardiac and thoracic Select Crowd Review crowds for their valuable input. The message concluded by acknowledging the Thieme Publishing Group's partnership with "Publons" to officially recognize and credit reviewers for their contributions. [Extracted from the article]

The article presents the discussion on catheter ablation being a highly effective treatment for most cardiac arrhythmias. Topics include well‐established efficacy showing a detailed understanding of the biophysiological processes in lesion development with RF ablation; and single‐shot balloon device, cryo‐ablation, laser energy, and high‐intensity focused ultrasound (HIFU).

The article comments on the structure of the coronary sinus Marshall ligament/vein in different atrial arrythmias, citing a study on the amount and distribution of low voltage atrial tissue induced by vein of Marshall ethanol infusion combined with radiofrequency ablation. It points out strengths of the study including data on distribution of lesion sets and distinct fingerprint lesion pattern of VOM ethanol effusion. It considers consequences of VOM ethanol effusion in persistent AF ablation.

The article offers information on the May 2021 issue of the "Journal of Cardiovascular Electrophysiology" including the members of the editorial staff, the copyright details, and the delivery terms and legal title.

The author reflects on the study on catheter ablation on chronic atrial fibrillation (CAF) conducted by Thomas Rostock and colleagues. He states that this study by Rostock and his colleagues is a significant contribution to the arising literature on the use of extensive ablation approaches for treating patient s with more established type of AF.

Furthermore we would like to extend our gratitude to all the members of our cardiac B Select Crowd Review b crowd. We would like to extend our most sincere thanks to the 185 reviewers listed below. [Extracted from the article]

The article presents the masthead and the table of contents for the current issue of the publication, with topics that include electrophysiology, COVID-19 pandemic, and catheter ablation of atrial fibrillation.

An editorial is presented on residual carina conduction after attempted circumferential pulmonary vein isolation. Topics discussed include interventional treatment of atrial fibrillation (AF), the electrophysiology community debated whether electrical isolation of the pulmonary veins (PV) should be attempted as an electrophysiological endpoint; and interventional electrophysiologists and medical engineering focused their research on the development of appropriate methods and techniques.

Background: Oral anticoagulation therapy in individuals with atrial fibrillation (AF) reduces the risk of thromboembolic events at cost of an increased bleeding risk. Whether anticoagulation-related outcomes differ between patients with paroxysmal and sustained AF receiving anticoagulation is controversially discussed.Methods: In the present analysis of the prospective multi-center cohort study thrombEVAL, the incidence of anticoagulation-related adverse events was analyzed according to the AF phenotype. Information on outcome was centrally recorded over 3 years, validated via medical records and adjudicated by an independent review panel. Study monitoring was provided by an independent institution.Results: Overall, the sample comprised 1089 AF individuals, of whom n = 398 had paroxysmal AF and n = 691 experienced sustained AF. In Cox regression analysis with adjustment for potential confounders, sustained AF indicated an independently elevated risk of clinically relevant bleeding compared to paroxysmal AF [hazard ratio (HR) 1.40 (1.02; 1.93); P = 0.038]. For clinically relevant bleeding, a significant interaction of the pattern of AF type with concomitant heart failure (HF) was detected: HRHF 2.45 (1.51, 3.98) vs. HRno HF 0.85 (0.55, 1.34); Pinteraction = 0.003. In HF patients, sustained AF indicated also an elevated risk of major bleeding [HR 2.25 (1.26, 4.20); P = 0.006]. A simplified HAS-BLED score incorporating only information on age (> 65 years), bleeding history, and HF with sustained AF demonstrated better discriminative performance for clinically relevant bleeding than the original version: AUCHAS-BLED: 0.583 vs. AUCsimplifiedHAS-BLED: 0.642 (P = 0.004).Conclusions: In HF patients receiving oral anticoagulation, sustained AF indicates a substantially elevated risk of bleeding.Clinical Trial Registration: https://clinicaltrials.gov, identifier: NCT01809015. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The aim of this study was to evaluate a spatial correlation between active atrial fibrillation (AF) drivers measured by electrocardiographic imaging and complex fractionated atrial electrograms (CFAEs) in patients with persistent AF. Methods: Sixteen patients with persistent AF were included. A biatrial geometry relative to an array of 252‐body‐surface‐electrodes was obtained from a noncontrast computed tomography scan. The reconstructed unipolar AF electrograms were signal‐processed (ECVUE™, CardioInsight Technologies Inc., Cleveland, OH, USA) to identify AF drivers. Before driver ablation, a biatrial mapping using the NavX system (St. Jude Medical, St. Paul, MN, USA) was performed to identify CFAEs. CFAE and driver regions were then quantified and compared. Results: AF was terminated by driver ablation in 11/16 (70%) patients. The mean number of ablated driver regions was 4 ± 1 per patient. The most frequent driver locations were the inferior left atrium and coronary sinus, the right pulmonary veins, and the right atrium. In 49/63 (78%) of the driver locations, more than 75% of the driver site showed CFAEs. The mean ablated driver area was 58 ± 24 cm2 (19 ± 11% of total surface area). The mean CFAE area was 178 ± 59 cm2 (49 ± 16%). The percentage of non‐ablated CFAE area was 76 ± 13% of total CFAEs. In 9/11 patients with AF termination, the termination site showed CFAEs. Conclusions: There is a significant overlap between AF driver regions identified by the ECVUE™ system and CFAE areas identified by the NavX system. AF driver regions are smaller and mostly embedded in larger CFAE areas. Selective ablation of drivers in CFAE areas seems sufficient to terminate persistent AF in the majority of patients. [ABSTRACT FROM AUTHOR]

Aims: Different cardiac arrhythmias have been suggested to be associated with Danon disease, e.g. Wolff-Parkinson-White syndrome. However, a systematic electrophysiological investigation of patients with Danon disease is lacking thus far.Methods and Results: Seven patients with Danon disease (4 males, 35.8 ± 10.8 years; 3 females, 51.3 ± 19.9 years) from 3 different families were studied. In all patients, the presence of Danon disease was confirmed by western blot of biopsy material or genetic testing. The patients were characterized by 12-lead electrocardiogram (ECG), Holter ECG, echocardiography, and serial implantable cardioverter defibrillator (ICD) interrogations (in ICD recipients). All male patients underwent electrophysiological investigation (EP study). Asymptomatic ventricular tachyarrhythmias were documented in six of the seven patients. Moreover, 5 of the 7 patients suffered from atrial fibrillation (AF), with 1 of them experiencing thromboembolic stroke at the age of 30 years. In male patients, the initial QRS complex was characterized by a slurring upstroke and shortened PQ interval mimicking ventricular pre-excitation. One male patient showed initial QRS complex slurring with prolonged PR interval. However, the presence of an accessory pathway was excluded by an EP study in all patients. In female patients, initial QRS complex slurring was significantly less distinct. In four patients, ICD implantation was performed for primary prevention of sudden cardiac death. However, sustained ventricular arrhythmias were not documented in any of the patients.Conclusions: The present study indicates that the distinct surface ECG pattern in Danon disease is not associated with ventricular pre-excitation. Atrial fibrillation is frequently observed in these patients and may be associated with thromboembolic events in the young, while sustained ventricular arrhythmias occur less frequently than previously reported. [ABSTRACT FROM AUTHOR]

Background: Dabigatran etexilate, a direct thrombin inhibitor and non-vitamin K antagonist oral anticoagulant (NOAC), has been shown to effectively prevent thromboembolic events in patients with non-valvular atrial fibrillation (AF). However, there is a paucity of data on the antithrombotic efficacy and safety of dabigatran in the resolution of left atrial appendage (LAA) thrombi in AF patients. Objective: The primary objective of the RE-LATED AF trial is to assess whether dabigatran results in a faster complete LAA thrombus resolution as compared to vitamin K antagonist phenprocoumon. Secondary objectives are to assess the impact of dabigatran on complete LAA thrombus resolution rate within 6 weeks of treatment and change in LAA thrombus volume under treatment. Furthermore, this study aims to assess and compare safety and tolerability of dabigatran vs. phenprocoumon. Methods: The study is designed as a prospective, randomized, open-label, controlled, explorative, blinded endpoint (PROBE) trial. Patients with AF and left atrial appendage thrombus confirmed by transoesophageal echocardiography (TEE) will be randomized to receive either dabigatran (150 mg bid) or phenprocoumon (INR 2-3) for the resolution of LAA thrombus formation for at least 21 days. Thrombus resolution will be determined by TEE 3 weeks after treatment initiation and subsequently at weeks 4 and 6, if the LAA thrombus has not been resolved before. A total of 110 patients are planned to be randomized. Conclusion: This is the first prospective, multicentre, randomized controlled clinical trial investigating safety and efficacy of a NOAC for the resolution of LAA thrombi in patients with non-valvular AF. [ABSTRACT FROM AUTHOR]

Primary Persistent AF. Introduction: Persistent atrial fibrillation (persAF) can occur either as a sustained arrhythmia that has progressed from initially paroxysmal AF or as primary persAF without a history of any spontaneously terminated episode. There is a paucity of data differentiating between the 2 different persAF entities. Thus, we prospectively evaluated baseline characteristics, electrophysiological features, and ablation outcome in these 2 patient cohorts. Methods and results: A total number of 154 consecutive persAF patients (63 ± 10 years, f = 42, longstanding persAF = 60) were characterized in terms of having primary persAF (P-persAF group) or persAF that secondarily progressed from paroxysmal AF (S-persAF group). All patients underwent de novo catheter ablation using the stepwise approach. PersAF entities were characterized by detailed patient history, sequential Holter monitoring, and reports of documented modes of AF conversion, respectively. The P-persAF group had a higher number of young patients (<50 years), a shorter AF history, and a higher number of congestive heart failure. The HATCH score did not differ between the groups. Procedural AF termination rate was significantly higher in S-persAF than in P-persAF patients (n = 55 [81%] vs. n = 58 [68%], P = 0.043). At 1-year follow-up, the arrhythmia-free survival after a single procedure was significantly lower in patients with P-persAF (26% vs. 43%, P = 0.016). Categorization to P-persAF was the strongest independent predictor of arrhythmia recurrence. Conclusions: P-persAF seems to be a specific arrhythmia entity that is associated with a lower AFtermination rate and a worse outcome after catheter ablation as compared to S-persAF. [ABSTRACT FROM AUTHOR]

Audible Steam Pops During Left Atrial Catheter Ablation Introduction Open irrigated radiofrequency (RF) ablation catheters with a porous tip (56 holes, TC-SF) permit delivering RF energy in a temperature-controlled mode without temperature rise. This prospective observational study investigated the association of different catheter parameters on the occurrence of audible steam pops during left atrial (LA) ablation. Methods and Results A total of 226 patients underwent TC-SF catheter ablation for atrial fibrillation. RF power delivery, impedance and catheter tip temperature were continually recorded throughout the ablation. Pulmonary vein isolation was performed with a maximum of 27 W and LA electrogram-guided or linear ablation with a maximum of 30 W. A total of 59 audible steam pops occurred, 2 of them resulting in pericardial tamponade. In the initial 89 patients, with an irrigation flow rate of 10 mL/min, 18 steam pops with one tamponade occurred in 12 (14%) patients. Subsequently, the irrigation flow rate was increased to 20 mL/min in the following 137 patients, resulting in the occurrence of 41 steam pops including one case of tamponade in a total of 30 (22%) patients. The maximal power was significantly higher in RF applications associated with a pop than those that did not. In only 12 (20%) steam pops, a significant impedance change occurred immediately before pop occurrence (4 [7%] impedance rise >10 ohm, 8 [13%] impedance drop >15 ohm). Conclusions The TC-SF catheter does not provide sufficient feedback from the ablated tissue to prevent steam popping. [ABSTRACT FROM AUTHOR]