Feasibility and safety of zero-fluoroscopy left bundle branch pacing: An initial experience.

INTRODUCTION: Left bundle branch pacing (LBBP) has emerged in recent years as a new pacing modality, providing patients with a narrower paced QRS than conventional pacing and stable pacing parameters. At the same time, there is a growing concern about the use of fluoroscopy in pacemaker implantations, given its harmful effects on both patients and operators. However, there are no prior experiences of zero-fluoroscopy in LBBP procedure. METHODS: We conducted an observational prospective study recruiting consecutive patients that underwent zero-fluoroscopy LBBP pacemaker implantation. A 6-month follow-up visit was programmed for every patient. The main goal of our study was to assess the efficacy, feasibility, and safety of the procedure. RESULTS: From January 2021 to February 2022, we included 10 patients, 8 males. The average age was 63 ± 4 years. The procedure was successful in all patients. We observed a significant reduction in paced QRS width compared with basal QRS width (149 ± 31.9 vs. 116 ± 15.6 ms, p = .02). All device parameters remained stable at 6-month follow-up: no significant differences in mean impedance (700.5 ± 136.4 vs. 494 ± 72.7 Ohm, p = .09), capture threshold (0.67 ± 0.2 vs. 0.83 ± 0.2 V @ 0.4 ms, p = .27) or endocardial V-wave amplitude (10.6 ± 5.2 vs. 13.9 ± 6.3 mV, p = .19). No complications were reported in any case. CONCLUSION: Zero-fluoroscopy LBBP is feasible and safe, and it may be considered in cases where radiation exposure is contraindicated or especially undesirable. Future randomized clinical trials are needed for the widespread use of this new technique.

Clinical impact of remote heart failure management using the multiparameter ICD HeartLogic alert.

INTRODUCTION AND OBJECTIVES: The multiparametric implantable cardioverter-defibrillator HeartLogic index has proven to be a sensitive and timely predictor of impending heart failure (HF) decompensation. We evaluated the impact of a standardized follow-up protocol implemented by nursing staff and based on remote management of alerts. METHODS: The algorithm was activated in HF patients at 19 Spanish centers. Transmitted data were analyzed remotely, and patients were contacted by telephone if alerts were issued. Clinical actions were implemented remotely or through outpatient visits. The primary endpoint consisted of HF hospitalizations or death. Secondary endpoints were HF outpatient visits. We compared the 12-month periods before and after the adoption of the protocol. RESULTS: We analyzed 392 patients (aged 69±10 years, 76% male, 50% ischemic cardiomyopathy) with implantable cardioverter-defibrillators (20%) or cardiac resynchronization therapy defibrillators (80%). The primary endpoint occurred 151 times in 86 (22%) patients during the 12 months before the adoption of the protocol, and 69 times in 45 (11%) patients (P<.001) during the 12 months after its adoption. The mean number of hospitalizations per patient was 0.39±0.89 pre- and 0.18±0.57 postadoption (P<.001). There were 185 outpatient visits for HF in 96 (24%) patients before adoption and 64 in 48 (12%) patients after adoption (P<.001). The mean number of visits per patient was 0.47±1.11 pre- and 0.16±0.51 postadoption (P<.001). CONCLUSIONS: A standardized follow-up protocol based on remote management of HeartLogic alerts enabled effective remote management of HF patients. After its adoption, we observed a significant reduction in HF hospitalizations and outpatient visits.

Spanish catheter ablation registry. 23rd official report of the Heart Rhythm Association of the Spanish Society of Cardiology (2023).

INTRODUCTION AND OBJECTIVES: We report the results of the 2023 Spanish catheter ablation registry. METHODS: Procedural data were collected and incorporated into the REDCap platform by all participating centers through a specific form. RESULTS: There were 104 participating centers in 2023 compared with 103 in 2022. In 2023, the total number of ablation procedures was 26 207, indicating a stabilization of the increase observed in 2022 following the pandemic. The increase was mainly due to procedures for atrial fibrillation (AF), with a total of 9942 ablations, representing 38% of all substrates. Notably, pulse-field ablation represented 10.3% of all AF ablation procedures, leading single-shot ablation strategies to outnumber point-by-point AF ablation for the first time in the history of the registry. Cavotricuspid isthmus ablation remained the second most targeted substrate (19% of all substrates, n=5067). The overall acute success rate remained high (97%), with a downward trend in the complication rate (1.6% vs 1.8% in 2022) and mortality rate (0.03%; n=7). Compared with 2022, there was a significant increase in procedures performed using electro-anatomical mapping and zero-fluoroscopy techniques for cavotricuspid isthmus ablation (52% vs 26%), AV node re-entrant tachycardia (48% vs 34%), and accessory pathways (62% vs 22%). We registered 466 ablations in pediatric patients. CONCLUSIONS: The data indicate a stabilization in the post-pandemic increase in ablation procedures, with an absolute and relative increase in AF as the predominant substrate. Success rates remained stable with a modest reduction in complication and mortality rates.

Local impedance and contact force guidance to predict successful cavotricuspid isthmus ablation with a zero-fluoroscopy approach.

Introduction: A new technology capable of monitoring local impedance (LI) and contact force (CF) has recently been developed. At the same time, there is growing concern regarding catheter ablation performed under fluoroscopy guidance, due to its harmful effects for both patients and practitioners. The aim of this study was to assess the safety and effectiveness of zero-fluoroscopy cavotricuspid isthmus (CTI) ablation monitoring LI drop and CF as well as to elucidate if these parameters can predict successful radiofrequency (RF) applications in CTI ablation. Methods: We conducted a prospective observational study recruiting 50 consecutive patients who underwent CTI ablation. A zero-fluoroscopy approach guided by the combination of LI drop and CF was performed. In each RF application, CF and LI drop were monitored. A 6-month follow-up visit was scheduled to assess recurrences. Results: A total of 767 first-pass RF applications were evaluated in 50 patients. First-pass effective RF applications were associated with greater LI drops: absolute LI drops (30.05 ± 6.23 Ω vs. 25.01 ± 5.95 Ω), p = 0.004) and relative LI drops (-23.3 ± 4.9% vs. -18.3 ± 5.6%, p = 0.0005). RF applications with a CF between 5 and 15 grams achieved a higher LI drop compared to those with a CF below 5 grams (29.4 ± 8.76 Ω vs. 24.8 ± 8.18 Ω, p < 0.0003). However, there were no significant differences in LI drop between RF applications with a CF between 5 and 15 grams and those with a CF beyond 15 grams (29.4 ± 8.76 Ω vs. 31.2 ± 9.81 Ω, p = 0.19). CF by itself, without considering LI drop, did not predict effective RF applications (12.3 ± 7.54 g vs. 11.18 ± 5.18 g, p = 0.545). Successful CTI ablation guided by a zero-fluoroscopy approach was achieved in all patients. Only one patient experienced a recurrence during the 6-month follow-up. Conclusions: LI drop (absolute and relative values) appears to be a good predictor of successful RF applications to achieve CTI conduction block. The optimal CF to achieve a good LI drop is between 5 and 15 g. A zero-fluoroscopy approach guided by LI and CF was feasible, effective, and safe.

Results of catheter ablation with zero or near zero fluoroscopy in pediatric patients with supraventricular tachyarrhythmias.

INTRODUCTION AND OBJECTIVES: Ionizing radiation exposure in catheter ablation procedures carries health risks, especially in pediatric patients. Our aim was to compare the safety and efficacy of catheter ablation guided by a nonfluoroscopic intracardiac navigation system (NFINS) with those of an exclusively fluoroscopy-guided approach in pediatric patients. METHODS: We analyzed catheter ablation results in pediatric patients with high-risk accessory pathways or supraventricular tachycardia referred to our center during a 6-year period. We compared fluoroscopy-guided procedures (group A) with NFINS guided procedures (group B). RESULTS: We analyzed 120 catheter ablation procedures in 110 pediatric patients (11±3.2 years, 70% male); there were 62 procedures in group A and 58 in group B. We found no significant differences between the 2 groups in procedure success (95% group A vs 93.5% group B; P=.53), complications (1.7% vs 1.6%; P=.23), or recurrences (7.3% vs 6.9%; P = .61). However, fluoroscopy time (median 1.1minutes vs 12minutes; P <.0005) and ablation time (median 96.5seconds vs 133.5seconds; P=.03) were lower in group B. The presence of structural heart disease was independently associated with recurrence (P=.03). CONCLUSIONS: The use of NFINS to guide catheter ablation procedures in pediatric patients reduces radiation exposure time. Its widespread use in pediatric ablations could decrease the risk of ionizing radiation.

His-Bundle Pacing in a Patient With Tricuspid and Mitral Prosthetic Valves Without Suitable Coronary Veins for Lead Placement.

Atrioventricular block in patients with a prosthetic tricuspid valve and a pacemaker with a dysfunctional epicardial lead is not uncommon. In such instances, coronary sinus lead placement is the preferred option, but it has a failure rate of 10%-15%. An atrial transseptal left ventricular lead placement has been proposed as an alternative, but this approach is not feasible in patients with a prosthetic mitral valve. This analysis represents the first reported case of His-bundle pacing from the atria in a patient with prosthetic tricuspid and mitral valves, with no suitable coronary veins for lead placement.

Le bloc auriculo-ventriculaire n'est pas rare chez les patients ayant reçu une valve tricuspide prothétique et porteurs d'un stimulateur cardiaque dont la sonde épicardique est dysfonctionnelle. Dans de tels cas, le positionnement de la sonde sur le sinus coronaire est l'option à privilégier, mais son taux d'échec varie entre 10 et 15 %. L'implantation de la sonde sur le ventricule gauche par la voie transsetale a été proposée à titre de solution de rechange, mais cette approche n'est pas envisageable chez les patients ayant reçu une valve mitrale prothétique. La présente analyse constitue le premier cas de stimulation du faisceau de His à partir des oreillettes chez un patient ayant reçu des valves tricuspides et mitrales prothétiques, en l'absence de veines coronaires se prêtant à l'implantation de la sonde.

[Atrial fibrillation predictors in patients with embolic stroke of undetermined source]. / Predictores de fibrilación auricular en pacientes con ictus embólico de origen indeterminado.

BACKGROUND AND OBJECTIVES: Atrial fibrillation (AF) detection in patients with embolic stroke of underdetermined source (ESUS) entails a change of medical treatment and a significant decrease in the incidence of new strokes. It is necessary to determine which patients would benefit more from prolonged electrocardiographic monitoring. Our aim was to find electrocardiographic and echocardiographic AF predictors in patients with ESUS. METHODS: We performed a cohort study that included 95 consecutive patients admitted to the hospital because of an ESUS. An electrocardiogram, each subject in the study underwent a 24-hour Holter-electrocardiogram (Holter-ECG) and an echocardiogram. A 2-year follow up was also conducted, with a 24-hour Holter-ECG every 3months for the first year, and every 6months during the second one. RESULTS: During the follow-up, AF was detected in 11 patients (11.6%), with a detection rate of 3.2% at 6months, 7.4% at 12months, and 11.6% at 18months as well as at 24months. The variables that were independently related to AF detection included moderate or severe left atrium dilation (P=.02), interatrial advanced block (P=.04) and more than 1000 premature atrial beats on 24-hour Holter-ECG (P=.01). CONCLUSIONS: Moderate or severe atrial dilation, interatrial advanced block, and the presence of more than 1000 premature atrial beats on 24-hour Holter-ECG behave as AF predictors in patients with ESUS.

Syncope and bifascicular block in the absence of structural heart disease.

The treatment of patients with bifascicular block (BFB) and syncope in the absence of structural heart disease (SHD) is not well defined. The objective of our study is to compare pacemaker empirical implantation with the use of electrophysiological studies (EPS). This is a prospective cohort study that included 77 patients with unexplained cardiogenic syncope and BFB without structural heart disease between 1997 and 2012. Two groups: 36 patients received empirical pacemakers (Group A) and 41 underwent EPS (Group B) to guide their treatment. The incidence of syncope recurrence and atrioventricular block was lower in group A. Mortality and complication rates were similar between both groups. Multivariate analysis demonstrated a higher number of events (combined endpoint) in group B. Our study shows that treatment according to EPS does not improve the results of a treatment strategy based on empirical pacemaker.