Pre-Excited Atrial Fibrillation in Wolff-Parkinson-White (WPW) Syndrome: A Case Report and a Review of the Literature.

Wolff-Parkinson-White (WPW) syndrome is defined by specific electrocardiogram (ECG) changes resulting in ventricular pre-excitation (the so-called WPW pattern), related to the presence of an accessory pathway (AP), combined with recurrent tachyarrhythmias. WPW syndrome is characterized by different supraventricular tachyarrhythmias (SVT), including atrioventricular re-entry tachycardia (AVRT) and atrial fibrillation (AF) with rapid ventricular response, with AVRT being the most common arrhythmia associated with WPW, and AF occurring in up to 50% of patients with WPW. Several mechanisms might be responsible for AF development in the WPW syndrome, and a proper electrocardiographic interpretation is of pivotal importance since misdiagnosing pre-excited AF could lead to the administration of incorrect treatment, potentially inducing ventricular fibrillation (VF). Great awareness of pre-excited AF's common ECG characteristics as well as associated causes and its treatment is needed to increase diagnostic performance and improve patients' outcomes. In the present review, starting from a paradigmatic case, we discuss the characteristics of pre-excited AF in the emergency department and its management, focusing on the most common ECG abnormalities, pharmacological and invasive treatment of this rhythm disorder.

Sex differences among subcutaneous implantable cardioverter-defibrillator recipients: a propensity-matched, multicentre, international analysis from the i-SUSI project.

AIMS: Women have been historically underrepresented in implantable cardioverter-defibrillator (ICD) trials. No data on sex differences regarding subcutaneous ICDs (S-ICD) carriers have been described. Aim of our study was to investigate sex-related differences among unselected S-ICD recipients. METHODS AND RESULTS: Consecutive patients enrolled in the multicentre, international i-SUSI registry were analysed. Comparisons between sexes were performed using a 1:1 propensity matching adjusted analysis for age, body mass index (BMI), left ventricular function, and substrate. The primary outcome was the rate of appropriate shocks during follow-up. Inappropriate shocks and other device-related complications were deemed secondary outcomes. A total of 1698 patients were extracted from the i-SUSI registry; 399 (23.5%) were females. After propensity matching, two cohorts of 374 patients presenting similar baseline characteristics were analysed. Despite similar periprocedural characteristics and a matched BMI, women resulted at lower risk of conversion failure as per PRAETORIAN score (73.4% vs. 81.3%, P = 0.049). Over a median follow-up time of 26.5 [12.7-42.5] months, appropriate shocks were more common in the male cohort (rate/year 3.4% vs. 1.7%; log-rank P = 0.049), while no significant differences in device-related complications (rate/year: 6.3% vs. 5.8%; log-rank P = 0.595) and inappropriate shocks (rate/year: 4.3% vs. 3.1%; log-rank P = 0.375) were observed. After controlling for confounders, sex remained significantly associated with the primary outcome (aHR 1.648; CI 0.999-2.655, P = 0.048), while not resulting predictor of inappropriate shocks and device-related complications. CONCLUSION: In a propensity-matched cohort of S-ICD recipients, women are less likely to experience appropriate ICD therapy, while not showing higher risk of device-related complications. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT0473876.

Impact of ventricular tachycardia ablation in subcutaneous implantable cardioverter defibrillator carriers: a multicentre, international analysis from the iSUSI project.

AIMS: Catheter ablation (CA) of ventricular tachycardia (VT) has become an important tool to improve clinical outcomes in patients with appropriate transvenous implantable cardioverter defibrillator (ICD) shocks. The aim of our analysis was to test whether VT ablation (VTA) impacts long-term clinical outcomes even in subcutaneous ICD (S-ICD) carriers. METHODS AND RESULTS: International Subcutaneous Implantable Cardioverter Defibrillator (iSUSI) registry patients who experienced either an ICD shock or a hospitalization for monomorphic VT were included in this analysis. Based on an eventual VTA after the index event, patients were divided into VTA+ vs. VTA- cohorts. Primary outcome of the study was the occurrence of a combination of device-related appropriate shocks, monomorphic VTs, and cardiovascular mortality. Secondary outcomes were addressed individually. Among n = 1661 iSUSI patients, n = 211 were included: n = 177 experiencing ICD shocks and n = 34 hospitalized for VT. No significant differences in baseline characteristics were observed. Both the crude and the yearly event rate of the primary outcome (5/59 and 3.8% yearly event rate VTA+ vs. 41/152 and 16.4% yearly event rate in the VTA-; log-rank: P value = 0.0013) and the cardiovascular mortality (1/59 and 0.7% yearly event rate VTA+ vs. 13/152 and 4.7% yearly event rate VTA-; log-rank P = 0.043) were significantly lower in the VTA + cohort. At multivariate analysis, VTA was the only variable remaining associated with a lower incidence of the primary outcome [adjusted hazard ratio 0.262 (0.100-0.681), P = 0.006]. CONCLUSION: In a real-world registry of S-ICD carriers, the combined study endpoint of arrhythmic events and cardiovascular mortality was lower in the patient cohort undergoing VTA at long-term follow-up. CLINICALTRIALS.GOV IDENTIFIER: NCT0473876.

Atrial fibrillation recurrences during the blanking period after catheter ablation with the laser balloon technique.

INTRODUCTION: Regardless of the catheter ablation (CA) for atrial fibrillation (AF) strategy, the role of early recurrences during the blanking period (BP) is still unclear. Our aim was to evaluate atrial tachyarrhythmias (ATAs) recurrences during the BP after CA with the laser-balloon (LB) technique. METHODS: Consecutive patients undergoing LBCA were enrolled. Primary outcome of the study was the overall crude ATA recurrence rate during the BP. ATA recurrences after the BP and in-hospital readmissions during the BP were deemed secondary outcomes. RESULTS: Two hundred and twenty-four patients underwent CA with the LB. Median age was 63.0 (55.5-69.5) years and 74.1% were males. 28.6% were persistent AF patients, and 34.8% of patients were followed up with a loop recorder. 15.6% of patients experienced at least an ATA recurrence during the BP. Male sex, chronic heart failure, persistent AF, and recurrences during the BP were found to be associated with long-term ATA recurrences. Recurrences during the BP remained associated with the outcome of interest at multivariate analysis (hazard ratio [HR] = 12.393, 95% confidence interval [95% CI] = 3.699-41.865, p < .001). An association over time was found between early and late recurrences, with 73.7%, 45.5%, and 10.8% of patients presenting with recurrences at 1-, 2-, and 3-month follow-up being free from recurrences after the BP, respectively. 8.0% of patients were readmitted during the BP: 4.5% for AF electrical cardioversion, and 1.8% for CA of other atrial arrhythmias; no redo CA was performed. CONCLUSION: After adjusting for confounders, ATA recurrences during the BP represent the most significant predictor of ATA recurrences after the BP, regardless of AF pattern.

Prevalence of atrial fibrillation and procedural outcome in patients undergoing catheter ablation for premature ventricular complexes.

INTRODUCTION: Atrial fibrillation (AF) and premature ventricular complexes (PVC) are common arrhythmias. We aimed to investigate AF prevalence in patients with PVC and its impact on PVC ablation outcomes. METHODS: Consecutive patients undergoing PVC ablation at a single institution between 2016 and 2019 were included and prospectively followed for 2 years. Patients with severe valvular heart disease, hyperthyroidism, malignancy, alcohol use disorder and advanced renal/hepatic diseases were excluded. Twelve-lead electrocardiograms were used to diagnose AF and assess PVC morphology. All PVCs were targeted for ablation using 4-mm irrigated-tip catheters at standardized radiofrequency power guided by 3-D mapping and intracardiac echocardiography. Patients were followed with remote monitoring, device interrogations and office visits every 6 months for 2 years. Detection of any PVCs in follow-up was considered as recurrence. RESULTS: A total of 394 patients underwent PVC ablation and 96 (24%) had concurrent AF. Patients with PVC and AF were significantly older (68.2 ± 10.8 vs. 58.3 ± 15.8 years, p < .001), had lower LV ejection fraction (43.3 ± 13.3% vs. 49.6 ± 12.4%, p < .001), higher CHA2 DS2 -VASc (2.8 ± 1.3 vs. 2.0 ± 1.3, p < .001) than those without. PVCs with ≥2 morphologies were detected in 60.4% and 13.7% patients with vs without AF (p < .001). At 2-year follow-up, PVC recurrence rate was significantly higher in patients with vs without AF (17.7% vs. 9.4%, p = .02). CONCLUSION: AF was documented in 1/4 of patients undergoing PVC ablation and was associated with lower procedural success at long-term follow-up. This was likely attributed to older age, worse LV function and higher prevalence of multiple PVC morphologies in patients with concurrent AF.

Incidence of ventricular arrhythmias related to COVID infection and vaccination in patients with Brugada syndrome: Insights from a large Italian multicenter registry based on continuous rhythm monitoring.

INTRODUCTION: Brugada syndrome (BrS) has a dynamic ECG pattern that might be revealed by certain conditions such as fever. We evaluated the incidence and management of ventricular arrhythmias (VAs) related to COVID-19 infection and vaccination among BrS patients carriers of an implantable loop recorder (ILR) or implantable cardioverter-defibrillator (ICD) and followed by remote monitoring. METHODS: This was a multicenter retrospective study. Patients were carriers of devices with remote monitoring follow-up. We recorded VAs 6 months before COVID-19 infection or vaccination, during infection, at each vaccination, and up to 6-month post-COVID-19 or 1 month after the last vaccination. In ICD carriers, we documented any device intervention. RESULTS: We included 326 patients, 202 with an ICD and 124 with an ILR. One hundred and nine patients (33.4%) had COVID-19, 55% of whom developed fever. Hospitalization rate due to COVID-19 infection was 2.76%. After infection, we recorded only two ventricular tachycardias (VTs). After the first, second, and third vaccines, the incidence of non-sustained ventricular tachycardia (NSVT) was 1.5%, 2%, and 1%, respectively. The incidence of VT was 1% after the second dose. Six-month post-COVID-19 healing or 1 month after the last vaccine, we documented NSVT in 3.4%, VT in 0.5%, and ventricular fibrillation in 0.5% of patients. Overall, one patient received anti-tachycardia pacing and one a shock. ILR carriers had no VAs. No differences were found in VT before and after infection and before and after each vaccination. CONCLUSIONS: From this large multicenter study conducted in BrS patients, followed by remote monitoring, the overall incidence of sustained VAs after COVID-19 infection and vaccination is relatively low.

Temporal association between drops in thoracic impedance and malignant ventricular arrhythmia: A longitudinal analysis of remote monitoring trends.

INTRODUCTION: Thoracic impedance (TI) drops measured by implantable cardioverter-defibrillators (ICDs) have been reported to correlate with ventricular tachycardia/fibrillation (VT/VF). The aim of our study was to assess the temporal association of decreasing TI trends with VT/VF episodes through a longitudinal analysis of daily remote monitoring data from ICDs and cardiac resynchronization therapy defibrillators (CRT-Ds). METHODS AND RESULTS: Retrospective data from 2384 patients were randomized 1:1 into a derivation or validation cohort. The TI decrease rate was defined as the percentage of rolling weeks with a continuously decreasing TI trend. The derivation cohort was used to determine a TI decrease rate threshold for a ≥99% specificity of arrhythmia prediction. The associated risk of VT/VF episodes was estimated in the validation cohort by dividing the available follow-up into 60-day assessment intervals. Analyses were performed separately for 1354 ICD and 1030 CRT-D patients. During a median follow-up of 2.0 years, 727 patients (30.4%) experienced 3298 confirmed VT/VF episodes. In the ICD group, a TI decrease rate of >60% was associated with a higher risk of VT/VF episode in a 60-day assessment interval (stratified hazard ratio, 1.42; 95% confidence interval (CI), 1.05-1.92; p = .023). The TI decrease preceded (40.8%) or followed (59.2%) the VT/VF episodes. In the CRT-D group, no association between TI decrease and VT/VF episodes was observed (p = .84). CONCLUSION: In our longitudinal analysis, TI decrease was associated with VT/VF episodes only in ICD patients. Preventive interventions may be difficult since episodes can occur before or after TI decrease.

Cardiac resynchronization therapy: present and future.

Cardiac resynchronization therapy (CRT) via biventricular pacing (BVP) is a well-established therapy for patients with heart failure with reduced ejection fraction and left bundle branch block, who remain symptomatic despite optimal medical therapy. Despite the long-standing clinical evidence, as well as the familiarity of cardiac electrophysiologists with the implantation technique, CRT via BVP cannot be achieved or may result ineffective in up to one-third of the patients. Therefore, new alternative techniques, such as conduction system pacing and left ventricular pacing, are emerging as potential alternatives to this technique, not only in case of BVP failure, but also as a stand-alone first choice due to several potential advantages over traditional CRT. Specifically, due to its procedural characteristics, left bundle branch area pacing appears to be the most convincing technique, showing comparable efficacy outcomes when compared with traditional CRT, not increasing short-term device-related complications, as well as improving procedural times. However, transvenous leads remain a major limitation of all these pacing modalities. To overcome this limit, a leadless left ventricular endocardial pacing has been developed as an additional tool to achieve a left endocardial activation, although being still associated with non-negligible pitfalls, limiting its current use in clinical practice. This article focuses on the current state and latest progresses in cardiac resynchronization therapy.

HeartLogic™: real-world data-efficiency, resource consumption, and workflow optimization.

Heart failure (HF) is a major and still growing medical problem and is characterized by episodes of acute decompensation that are associated with a negative prognosis and a significant burden on the patients, doctors, and healthcare resources. Early detection of incipient HF may allow outpatient treatment before patients severely decompensate, thus reducing HF hospitalizations and related costs. The HeartLogic™ algorithm is an automatic, remotely managed system combining data directly related to HF pathophysiology into a single score, the HeartLogic™ index. This index proved to be effective in predicting the risk of incipient HF decompensation, allowing to redistribute resources from low-risk to high-risk patients in a timely and cost-saving manner. The alert-based remote management system seems more efficient than the one based on scheduled remote transmission in terms of caregivers' workload and alert detection timing. The widespread application of the HeartLogic™ algorithm requires the resolution of logistical and financial issues and the adoption of a pre-defined, functional workflow. In this paper, we reviewed general aspects of remote monitoring in HF patients, the functioning and pathophysiological basis of the HeartLogic index, its efficiency in the management of HF patients, and the economic effects and the organizational revolution associated with its use.

Protection against Ischemic Heart Disease: A Joint Role for eNOS and the KATP Channel.

Genetic susceptibility may influence ischemic heart disease (IHD) predisposition and affect coronary blood flow (CBF) regulation mechanisms. The aim of this study was to investigate the association among single nucleotide polymorphisms (SNPs) of genes encoding for proteins involved in CBF regulation and IHD. A total of 468 consecutive patients were enrolled and divided into three groups according to coronary angiography and intracoronary functional tests results: G1, patients with coronary artery disease (CAD); G2, patients with coronary microvascular dysfunction (CMD); and G3, patients with angiographic and functionally normal coronary arteries. A genetic analysis of the SNPs rs5215 of the potassium inwardly rectifying channel subfamily J member 11 (KCNJ11) gene and rs1799983 of the nitric oxide synthase 3 (NOS3) gene, respectively encoding for the Kir6.2 subunit of ATP sensitive potassium (KATP) channels and nitric oxide synthase (eNOS), was performed on peripheral whole blood samples. A significant association of rs5215_G/G of KCNJ11 and rs1799983_T/T of NOS3 genes was detected in healthy controls compared with CAD and CMD patients. Based on univariable and multivariable analyses, the co-presence of rs5215_G/G of KCNJ11 and rs1799983_T/T of NOS3 may represent an independent protective factor against IHD, regardless of cardiovascular risk factors. This study supports the hypothesis that SNP association may influence the crosstalk between eNOS and the KATP channel that provides a potential protective effect against IHD.

Left Atrial Appendage Closure: A Current Overview Focused on Technical Aspects and Different Approaches.

Several studies in literature have shown that 90% of emboli related to non-valvular atrial fibrillation originate from left atrial appendage. Percutaneous closure or surgical exclusion of left atrial appendage in patients with high bleeding and high cardioembolic risk is currently a well established procedure in literature, clinical practice and guidelines. Knowledge of different techniques of left atrial appendage closure is necessary to individualize the procedure according to the patient anatomy and pre-procedural imaging evaluations. In this review the authors will evaluate different left atrial appendage closure systems and the different pre and intra procedural imaging methods.

Leadless Pacemaker Implantation in the Emergency Bradyarrhythmia Setting: Results from a Multicenter European Registry.

Background. Data on leadless pacemaker (LPM) implantation in an emergency setting are currently lacking. Objective. We aimed to investigate the feasibility of LPM implantation for emergency bradyarrhythmia, in patients referred for urgent PM implantation, in a large, multicenter, real-world cohort of LPM recipients. Methods. Two cohorts of LPM patients, stratified according to the LPM implantation scenario (patients admitted from the emergency department (ED+) vs. elective patients (ED−)) were retrieved from the iLEAPER registry. The primary outcome of the study was a comparison of the peri-procedural complications between the groups. The rates of peri-procedural characteristics (overall procedural and fluoroscopic duration) were deemed secondary outcomes. Results. A total of 1154 patients were enrolled in this project, with patients implanted due to an urgent bradyarrhythmia (ED+) representing 6.2% of the entire cohort. Slow atrial fibrillation and complete + advanced atrioventricular blocks were more frequent in the ED+ cohort (76.3% for ED+ vs. 49.7% for ED−, p = 0.025; 37.5% vs. 27.3%, p = 0.027, respectively). The overall procedural times were longer in the ED+ cohort (60 (45−80) mins vs. 50 (40−65) mins, p < 0.001), showing higher rates of temporary pacing (94.4% for ED+ vs. 28.9% for ED−, p < 0.001). Emergency LPM implantation was not correlated with an increase in the rate of major complications compared to the control group (6.9% ED+ vs. 4.2% ED−, p = 0.244). Conclusion. LPM implantation is a feasible procedure for the treatment of severe bradyarrhythmia in an urgent setting. Urgent LPM implantation was not correlated with an increase in the rate of major complications compared to the control group, but it was associated with longer procedural times.

Intraprocedural PRAETORIAN score for early assessment of S-ICD implantation: A proof-of-concept study.

INTRODUCTION: The PRAETORIAN score (PS) was developed to assess the implant position and predict defibrillation success of the subcutaneous implantable cardioverter defibrillators (S-ICD). The main critique moved to the routine use of PS has been its postprocedural timing, that limits its usefulness on procedure guidance. The aim of this proof-of-concept study was to assess the feasibility of an intraprocedural use of PS. METHODS: Forty consecutive patients undergoing S-ICD implantation were enrolled. Intraprocedural PS (IP-PS) obtained with fluoroscopy before closure of the pocket and postprocedural PS (PP-PS) obtained with two-views chest X-ray were compared. Intraprocedural data and PS were compared with the historic cohorts of the involved institutions. RESULTS: When assessing IP-PS and PP-PS, a complete overall agreement was observed (100%, 1.00-κ; p < .001). When assessing a per-step agreement, a very high-degree of concordance in evaluating Step 1 of the PS was observed (95%, 0.81-κ; p < .001). A complete agreement in Step 2-3 (100%, 1.00-κ; p < .001) of the PS was reported. In comparison with our historical cohort, procedural time in the IP-PS cohort did not increase (45 [41-52] vs. 45 [39-49] min; p = .351) while the expected increase in fluoroscopy time resulted scarce (15 [10-15] s). CONCLUSION: An IP-PS can be reliably obtained using fluoroscopy guidance during S-ICD implantation, without a significant increase in procedural duration and may serve as guidance for implanting physicians, to avoid postprocedural S-ICD repositioning, leading to patient discomfort and significantly enhancing infective risks. IP-PS showed a very high agreement with the PP-PS obtained from two-views chest X-ray.

Etiology and device therapy in complete atrioventricular block in pediatric and young adult population: Contemporary review and new perspectives.

Complete atrioventricular block (CAVB) is a total dissociation between the atrial and ventricular activity, in the absence of atrioventricular conduction. Several diseases may result in CAVB in the pediatric and young-adult population. Permanent right ventricular (RV) pacing is required in permanent CAVB, when the cause is neither transient nor reversible. Continuous RV apical pacing has been associated with unfavorable outcomes in several studies due to the associated ventricular dyssynchrony. This study aims to summarize the current literature regarding CAVB in the pediatric and young adult population and to explore future treatment perspectives.

Clinical presentation, diagnosis, and treatment of atrioesophageal fistula resulting from atrial fibrillation ablation.

BACKGROUND: Atrioesophageal fistula (AEF) is a worrisome complication of atrial fibrillation (AF) ablation. Its clinical manifestations and time course are unpredictable and may contribute to diagnostic and treatment delays. We conducted a systematic review of all available cases of AEF, aiming at characterizing clinical presentation, time course, diagnostic pitfalls, and outcomes. METHODS: The digital search retrieved 150 studies containing 257 cases, 238 (92.6%) of which with a confirmed diagnosis of AEF and 19 (7.4%) of pericardioesophageal fistula. RESULTS: The median time from ablation to symptom onset was 21 days (interquartile range [IQR]: 11-28). Neurological abnormalities were documented in 75% of patients. Compared to patients seen by a specialist, those evaluated at a walk-in clinic or community hospital had a significantly greater delay between symptom onset and hospital admission (median: 2.5 day [IQR: 1-8] vs. 1 day [IQR: 1-5); p = .03). Overall, 198 patients underwent a chest scan (computed tomography [CT]: 192 patients and magnetic resonance imaging [MRI]: 6 patients), 48 (24.2%; 46 CT and 2 MRI) of whom had normal/unremarkable findings. Time from hospital admission to diagnostic confirmation was significantly longer in patients with a first normal/unremarkable chest scan (p < .001). Overall mortality rate was 59.3% and 26.0% survivors had residual neurological deficits at the time of discharge. CONCLUSIONS: Since healthcare professionals of any specialty might be involved in treating AEF patients, awareness of the clinical manifestations, diagnostic pitfalls, and time course, as well as an early contact with the treating electrophysiologist for a coordinated interdisciplinary medical effort, are pivotal to prevent diagnostic delays and reduce mortality.

Clinical impact of defibrillation testing in a real-world S-ICD population: Data from the ELISIR registry.

BACKGROUND: Current guidelines recommend defibrillation testing (DT) performance in patients with a subcutaneous implantable cardioverter defibrillator (S-ICD), theoretically to reduce the amount of ineffective shocks. DT, however, has been proven unnecessary in transvenous ICD and real-world data show a growing trend in avoidance of DT after S-ICD implantation. METHODS: All patients undergoing S-ICD implant at nine associated Italian centers joining in the ELISIR registry (ClinicalTrials.gov Identifier: NCT04373876) were enrolled and classified upon DT performance. Long-term follow-up events were recorded and compared to report the long-term efficacy and safety of S-ICD implantations without DT in a real-world setting. RESULTS: A total of 420 patients (54.0 ± 15.5 years, 80.0% male) were enrolled in the study. A DT was performed in 254 (60.5%) patients (DT+ group), while in 166 (39.5%) was avoided (DT- group). Over a median follow-up of 19 (11-31) months, a very low rate (0.7%) of ineffective shocks was observed, and no significant differences in the primary combined arrhythmic outcome were observed between the two groups (p = .656). At regression analysis, the only clinical predictor associated with the primary combined outcome was S-ICD placement for primary prevention (odds ratio: 0.42; p = .013); DT performance instead was not associated with a reduction in primary outcome (p = .375). CONCLUSION: Implanting an S-ICD without DT does not appear to impact the safety of defibrillation therapy and overall patients' survival.

Atrioventricular and intraventricular blocks in the setting of acute coronary syndromes: a narrative review.

Acute coronary syndromes (ACS) might be complicated by atrioventricular (AV) and intraventricular (IV) blocks in a significant number of cases, and often represent a diagnostic and a therapeutic challenge. These conduction disturbances are predictors of adverse prognosis, with complete AV blocks presenting the most severe outcomes, showing an increased in-hospital mortality. With the advent of emergency percutaneous coronary intervention (PCI) and the end of the thrombolysis era, the incidence of both AV and IV blocks has surely decreased, but their prognosis in this setting still remains a matter of debate. The aim of this review is to evaluate the current knowledge on AV and IV blocks in the AMI setting with or without ST segment elevation.

Atrioventricular synchronous leadless pacemaker: state of art and broadened indications.

Leadless pacemakers (LLPMs) have become a major breakthrough in the management of bradyarrhythmia as an attractive alternative to the standard transvenous pacemakers (TV-PMs). Recently, the introduction of a second-generation LLPMs (Micra AV-MC1AVR1) has expanded pacing modes to obtain atrioventricular (AV) synchronous pacing, providing an interesting alternative in the actual scenario of leadless pacing. Nevertheless, actual reports have highlighted some concerns regarding those devices. In this review, we sought to provide an overview of this technology based on its approval studies and major reports.

Second-generation laser balloon ablation for the treatment of atrial fibrillation assessed by continuous rhythm monitoring: the LIGHT-AF study.

AIMS: Balloon-based technologies have been developed to simplify catheter ablation of atrial fibrillation (AF), to improve the clinical outcome of the procedure and to achieve durable pulmonary vein isolation (PVI). The objective of this study is to evaluate the safety and efficacy of second-generation laser balloon (LB2) ablation in the treatment of AF using a continuous cardiac rhythm monitoring strategy. Atrial tachyarrhythmias (ATas) recurrences were assessed with implantable cardiac monitors (ICMs) or devices. METHODS AND RESULTS: All patients underwent LB2 ablation procedure. The primary endpoint was the first recurrence of any, >5.5 and >24 h duration ATas after the blanking period (90 days). In-hospital visits were performed at 3, 6, and 12 months. Seventy-three patients (68% male, mean age 59.8 ± 11.3) were included in the study. The average procedure, fluoroscopy, and laser ablation times were 81.5 ± 30.1, 21.5 ± 12.4, and 33.8 ± 9.7, respectively. All PVs were isolated using the LB2 with no need of touch-up using focal catheters. No major complications occurred during or after the procedures. The one-year freedom from recurrences was 66.9% (95% CI: 57.0-76.7%), 81.0% (69.5-88.5%), and 86.8% (76.1-92.9%) considering any, 5.5-h and 24-h cut-off duration, respectively. At 3, 6, and 12 months, any ATas was recorded in 22%, 32%, and 25% of patients, with a ≥5% arrhythmic burden documented in 4%, 5%, and 3%, respectively. Few patients reported AF-related symptoms (7%, 8%, and 5%). CONCLUSION: LB2 ablation is a safe and effective procedure, showing a high freedom from recurrences and low arrhythmic burden as documented by a continuous rhythm monitoring strategy.

Targeting non-pulmonary vein triggers in persistent atrial fibrillation: results from a prospective, multicentre, observational registry.

AIMS: We evaluated the efficacy of an ablation strategy empirically targeting pulmonary veins (PVs) and posterior wall (PW) and the prevalence and clinical impact of extrapulmonary trigger inducibility and ablation in a large cohort of patients with persistent atrial fibrillation (PerAF). METHODS AND RESULTS: A total of 1803 PerAF patients were prospectively enrolled. All patients underwent pulmonary vein antrum isolation (PVAI) extended to the entire PW. A standardized protocol was performed to confirm persistent PVAI and elicit any triggers originating from non-PV sites. All non-PV triggers initiating sustained atrial tachyarrhythmias were ablated. Ablation of non-PV sites triggering non-sustained runs (<30 s) of atrial tachyarrhythmias or promoting frequent premature atrial complexes (≥10/min) was left to operator's discretion. Overall, 1319 (73.2%) patients had documented triggers from non-PV areas. After 17.4 ± 8.5 months of follow-up, the cumulative freedom from atrial tachyarrhythmias among patients without inducible non-PV triggers (n = 484) was 70.2%. Patients with ablation of induced non-PV triggers had a significantly higher arrhythmia control than those whose triggers were not ablated (67.9% vs. 39.4%, respectively; P < 0.001). After adjusting for clinically relevant variables, patients in whom non-PV triggers were documented but not ablated had an increased risk of arrhythmia relapse (hazard ratio: 2.39; 95% confidence interval: 2.01-2.83; P < 0.001). CONCLUSION: Pulmonary vein antrum isolation extended to the entire PW might provide acceptable long-term arrhythmia-free survival in PerAF patients without inducible non-PV triggers. In our population of PerAF patients, non-PV triggers could be elicited in ∼70% of PerAF patients and their elimination significantly improved outcomes.