Pace-Pacing and Clinical Electrophysiology最新文献

Background and aims: A novel multielectrode variable loop catheter (VLC) has been introduced for atrial fibrillation (AF) ablation enabling 3D electroanatomic mapping and concomitant pulsed field ablation (PFA). This study sought to investigate the VLC under routine clinical conditions for AF ablation.

Methods: Consecutive patients with symptomatic AF undergoing first-time AF ablation were prospectively enrolled. All procedures were carried out using the VLC. Electroanatomic mapping pre and post-ablation was conducted with the VLC and a high-density multipolar mapping catheter. The general ablation protocol consisted of four ablation pulses per pulmonary vein (PV). All procedures were conducted in conscious sedation.

Results: Forty-five patients (mean age 66.3 ± 6.1 years, 68.9% paroxysmal AF) were analyzed. Procedure duration was 66.3 ± 13.1 min. Acute pulmonary vein isolation (PVI) was achieved in 45 patients without periprocedural complications. Remapping after the initial 16 ablation pulses revealed sustained electrical conduction to at least one PV in six patients (13.3%). Repeat ablation was conducted and with an average of 7.5 ± 4.5 additional pulses. PV intubation during mapping was achieved in 168/180 PVs with the VLC (93.3%) and in 180/180PVs (100%) with the high-density mapping catheter (p < 0.001). Incomplete PV intubation during mapping did not result in incomplete PVI, as demonstrated by remapping utilizing the high-density mapping catheter. Adequate correlation between left atrial post-ablation remapping of low voltage areas and ablated regions was demonstrated in all patients.

Conclusion: PFA-guided AF ablation using the novel VLC is safe and effective. The integration into a 3D-electroanatomic mapping system enables adequate mapping during PFA procedures.

Introduction: Right bundle branch block (RBBB) following cardiac device extraction has not been previously reported but may have catastrophic consequences.

Methods and results: We present two cases of young male patients who developed RBBB following the extraction of single chamber TV ICD systems where the coil was adherent close to the superior tricuspid valve annulus. Both patients had a subcutaneous ICD (SICD) implanted but suffered an inappropriate shock due to T-wave oversensing, requiring very early SICD removal for one patient.

Conclusion: The development of RBBB following the extraction of a TV ICD is a previously unreported complication and may cause significant sensing problems if an SICD is implanted subsequently. Placement of the ICD lead tip in the right ventricular outflow tract or high on the intraventricular septum may predispose to this complication.

Most studies have followed patients with persistent atrial fibrillation (PeAF) using 12-lead or 24-h Holter electrocardiography, but this may overestimate the effectiveness of pulsed field ablation (PFA) in the treatment of PeAF. This study aimed to investigate the feasibility of PFA in patients with PeAF and follow-up using insertable cardiac monitoring that can provide information on the actual status of atrial arrhythmia (AA) recurrence after PFA. We prospectively enrolled 49 patients with PeAF who underwent PFA strategy comprising superior vena cava isolation, pulmonary vein isolation, and posterior wall box isolation between December 2022 and January 2024. After median follow-up of 14.1 months, 30 patients (61.22%) had zero AA burden. Kaplan-Meier analysis show that the freedom from recurrence increased with arrhythmia duration thresholds, from 59.54% to 80.50% (duration < 2 min vs. duration > 48 h, p = 0.040). Safety events occurred in two patients (one transient ischemic attack and one pseudoaneurysm). PFA is an effective modality for the treatment of patients with PeAF.

Background: The relationship between the burden of atrial fibrillation (AF) and the risk of ischemic stroke is crucial yet complex. This study examines this relationship to enhance stroke prediction in patients with AF.

Methods: The CABANA trial study from 2009 to 2016 analyzed the relationship between AF load, stroke, and anticoagulation. We matched age, gender, and race, as well as the control and case groups, at 1:4. Non-invasive electrocardiogram monitoring recorded load events and included the total cumulative load in the calculation. Next, we compared the net load between the stroke and control groups, and the relationship between net AF load and stroke was analyzed using univariate and multivariate logistic regression. This study also explored the interplay between stroke, AF load, and anticoagulation.

Results: The first independent predictor of ischemic stroke risk is the net AF load (OR = 8.72, 95% CI: 3.11-24.4, p < 0.001). Stratified by the CHA2DS2VASc score, no significant change in net AF load between the high-risk and low-risk groups was observed (p = 0.96). Finally, we categorized all patients into adequate and inadequate anticoagulation groups based on whether they received adequate anticoagulation. The net AF load in the adequate anticoagulation group was higher than in the inadequate anticoagulation group (p < 0.001).

Conclusion: AF burden is significantly associated with the risk of ischemic stroke. Determining the threshold of AF burden can improve stroke prevention strategies, indicating the need for targeted research on risk stratification and management of patients with AF.

Background: Our understanding of lesion transmurality and continuity of non-occlusive cryoballoon ablation (NOCA) is limited. In the present study, lesion dimensions under different conditions during NOCA were assessed.

Methods: Simulated NOCA was performed on freshly harvested canine left ventricular myocardial using the cryoballoon. We conducted experiments to evaluate the effects of (1) flow rate (0, 1, and 1.5 L/min) and freezing time (120, 150, and 180 ) on lesion dimensions during segmental NOCA and (2) overlapping manners between two sequential cryoablations (overlaps of half and two-thirds the balloon area) on lesion continuity during linear NOCA. Lesion formation was assessed after 3-5 h using tetrazolium chloride staining.

Results: (1) Experiments of segmental NOCA No differences were observed in maximal lesion depths among different flow rates (0, 1, and 1.5 L/min) across cryoballoon. For ablation duration, 120-s cryotherapy was able to penetrate to a maximal lesion depth of 6.45 ± 0.80 mm, significantly smaller than those for 150 and 180-s (p < 0.001). (2) Experiments of linear NOCA: Maximal lesion depths of 2 × 120-s linear NOCA were similar between two-thirds and half-size overlaps (p = 0.192). However, non-transmural lesions were more frequently observed in half-size than two-thirds overlap (56.3% vs. 6.3%, p = 0.002).

Conclusions: When performing NOCA, lesion depths did not vary significantly with convective flow around the CB. A 120-s cryoapplication seemed to yield enough lesion depth and longer cryotherapy should be applied cautiously at a place in close anatomical contact with the esophagus. Additionally, a series of sequential applications in a half-size overlapping manner might lead to non-transmural lesions in the ablation line.

Background: Transseptal puncture (TSP) is a widely utilized technique for left-sided electrophysiological studies (EPS), interventions in left heart lesions, or creating interatrial shunts in congenital heart diseases (CHD). This study aims to evaluate the outcome of TSP in children under 20 kg.

Methods: This retrospective study analyzed TSP procedures in infants and children <20 kg between December 2015 and January 2023. TSPs were performed with a biplane angiography system in the catheter angiography laboratory. A Brockenbrough needle (BRK Transseptal Needle; Abbott/St. Jude Medical, Inc.) was used for TSP. In patients whose Brockenbrough needles could not cross the interatrial septum, TSP was performed by applying cautery energy over the Brockenbrough needle.

Results: Nineteen patients were studied (seven females, median age 2.3 years, median weight 10.3 kg), and 63% required TSP for CHD. The CHD group had younger patients (median age: 6.25 months) with smaller weights (median: 5.3 kg) than the catheter ablation group. There was no difference between groups in terms of gender and success rates. Procedure and fluoroscopy times were shorter in the ablation group (p < 0.05). Radiofrequency energy was used without complications in three cases when traditional methods failed. In four patients, the septum could not be traversed. The median weight of patients in whom TSP failed was 2.9 kg. The only major complication was pericardial tamponade developed in two patients diagnosed with hypoplastic left heart syndrome.

Conclusion: TSP is a safe option when carefully selected but carries higher risks in complex CHD with abnormal cardiac anatomy compared to patients with normal anatomy used for electrophysiology procedures.

Intermittent P-wave non-tracking in pacemaker electrograms is an infrequent observation in routine clinical practice. While this finding may suggest significant device malfunction, it can also represent a benign response to advanced pacemaker algorithms. This article presents a differential diagnosis of intermittent P-wave non-tracking, with the aim of facilitating accurate interpretation and minimizing unnecessary diagnostic procedures.

Background: Periprocedural electrophysiological (EP) testing may be useful to predict high degree atrioventricular block (HAVB) risk in patients undergoing transcatheter aortic valve replacement (TAVR).

Objective: To determine whether pre- and immediate post-TAVR ECG and HV interval findings are predictive of HAVB.

Methods: Consecutive TAVR patients without prior pacemaker (PM) implantation underwent ECG and standardized HV interval measurements pre- and post-TAVR using the quadripolar catheter for rapid pacing. The primary outcome was HAVB >24 h after TAVR or ventricular pacing need RESULTS: Out of 97 included patients, 8 experienced the primary outcome (7 with HAVB and 1 with PM need). On univariate analysis, pre- and post-TAVR PR, post-TAVR HV, and Delta-HV intervals were predictors of the primary outcome. A Delta-HV interval ≥18 ms predicted HAVB with sensitivity = 50% and specificity = 90% (AUC = 0.708, PPV = 31%), while an HV interval ≥60 ms after TAVR had sensitivity = 63% and specificity = 79% (AUC = 0.681, PPV = 21%). None of the patients with a PR interval ≤180 ms post-TAVR experienced the primary outcome. Among patients with new-onset LBBB, an HV interval post-TAVR >65 ms was the only predictor of HAVB (AUC = 0.776, PPV = 33%, and NPV = 97%).

Conclusion: The yield of periprocedural EP assessment during TAVR is limited considering that about half of the at-risk patients fail to be identified. However, early periprocedural risk stratification may be more useful in the subset of patients with new-onset LBBB. Among ECG findings, a post-TAVR PR interval ≤180 ms identifies a subgroup at very low risk, independently of QRS interval and morphology.