Heart rhythm最新文献

Background: Although pulsed field ablation (PFA) is generally considered safe, the mechanisms underlying both symptomatic and silent embolic events remain unclear.

Objectives: This study aimed to investigate the timing, number, size, and characteristics of microembolic signals (MES) during each step of the pentaspline PFA procedure using real-time carotid Doppler monitoring.

Methods: MES were assessed during ablation procedures in 32 patients, including 27 who underwent pulmonary vein isolation (PVI) with the pentaspline PFA system and 5 control patients who received radiofrequency ablation limited to the right atrium.

Results: The PFA group showed significantly more MES than the control group. MES were detected throughout the PFA procedure, with the highest counts observed during PFA delivery to the right pulmonary veins (RPVs). Bubble signals were seen in all procedural steps. In contrast, high-intensity transient signals, which are mainly composed of solid components, were more common during PFA energy delivery. All 303 overcurrent errors-events in which energy delivery is stopped due to overcurrent detection-occurred during basket-type PFA applications and were associated with a marked increase in MES. Basket-configuration energy delivery resulted in a significantly higher number of MES than the flower-configuration, particularly in the RPVs. The size of MES was significantly larger during PFA energy delivery than during catheter or sheath manipulation.

Conclusions: This study demonstrated the characteristic timing, frequency, and morphology of MES during pentaspline PFA procedures, providing insights that may help reduce embolic risks in future practice.

Background: Pulsed field ablation (PFA) has emerged as a tissue-selective modality for atrial fibrillation (AF) ablation. Early recurrence of any atrial tachyarrhythmia (ERAT) during the blanking period are considered transient, however their association with late recurrence of any atrial tachyarrhythmias (LRAT) remains unclear.

Objective: The present meta-analysis aimed to elucidate the association between ERAT and LRAT post-PFA for different blanking cut-offs.

Methods: A search of MEDLINE, Scopus, and Cochrane (up to January 12, 2026) identified observational or randomized studies of PFA with ≥1-year follow-up. Double independent study selection, data extraction and quality assessment were performed. Random-effects frequentist models were used to pool odds ratios (OR), hazard ratios (HR), proportions and diagnostic accuracy measures with 95% confidence intervals (CI).

Results: Seven observational studies (3003 patients) were analyzed. ERATs within 0-90 days were strongly associated with LRATs (OR=8.98, 95%CI=[5.61,14.37]; I²=68%; 7 studies), without subgroup differences by AF type, use of event recorders or PFA technology. The positive predictive value (PPV) of ERATs was 0.66 (95%CI=[0.55,0.76]; I²=75%; 7 studies) within 0-90 days, 0.73 (95%CI=[0.63,0.81]; I²=23%; 3 studies) within 0-60 days and 0.56 (95%CI=[0.16,0.90]; I²=85%; 2 studies) within 0-30 days. ERATs within 0-90 days demonstrated high specificity (0.93, 95%CI=[0.90,0.95]) and positive likelihood ratio (5.83, 95%CI=[4.09,8.32]) for LRATs. Age, heart failure and non-pulmonary vein ablation were significant effect modifiers in metaregression analysis.

Conclusions: ERATs within 0-90 days and 0-60 days post-PFA are robust LRAT predictors, whereas first-month ERATs remain insufficiently investigated. Further studies are required to define the optimal blanking period post-PFA.

Background: Accurate assessment of arrhythmia propagation can help identify ablation targets, but current methods are limited by local activation time (LAT) variability, catheter orientation dependence, and inconsistent sampling density.

Objective: This study aimed to extend LAT-independent omnipolar technology to catheters with arbitrary electrode arrangements, compare estimates with LAT-derived equivalents, and demonstrate a weighted resampling algorithm that produces clear and robust visualizations of wavefront propagation.

Methods: Omnipolar estimates of conduction velocity (CV), activation direction (AD), and voltage were computed from electroanatomic mapping data from 34 scar-related reentrant atrial tachycardias and 1 ventricular tachycardia mapped with PENTARAY and OCTARAY catheters. Estimates were compared with conventional analogs to assess concordance, both globally and after stratification by anatomic region. To overcome sampling nonuniformity, a distance-weighted vector estimation, resampling, and smoothing algorithm (VERSA) was devised to render propagation metrics (CV and AD) into intuitive visualizations. Resulting VERSA maps were assessed qualitatively for their ability to convey local propagation and their agreement with conventional activation maps.

Results: Across all cases, omnipolar CV was higher than LAT-based CV, whereas differences in AD were negligible. Omnipolar voltages were significantly higher than the corresponding maximum bipolar voltages. The proposed VERSA maps intuitively depicted wavefront propagation, agreed broadly with activation maps, and illustrated conduction block, conduction breakthrough, and overall patterns of reentry.

Conclusion: Extending omnipolar technology to arbitrary electrode arrangements and visualizing measurements in VERSA maps can elucidate wavefront propagation in reentrant tachycardias without the need for LAT annotation. These methods could facilitate better interpretation of complex arrhythmia patterns and more effective ablation.

Ambulatory electrocardiogram (ECG) monitoring frequently identifies incidental arrhythmias, but their prevalence in community-based atrial fibrillation (AF) screening remains uncertain. For this systematic review, we searched PubMed, Embase, Cochrane, and CINAHL through January 2025 for studies on ECG abnormalities in community-based screening. Eligible studies included randomized trials or observational cohorts without prior AF that used ≥24-hour continuous rhythm monitoring and reported at least 1 incidental non-AF finding. We included 25 publications (17 cohorts, 136,344 participants; mean age 41-80 years, 0%-100% female). Non-AF abnormalities occurred in 4%-96%, including supraventricular and ventricular arrhythmias and conduction defects. Meta-analyses demonstrated substantial heterogeneity in the reported prevalences of most potentially serious incidental findings, and other non-AF abnormalities. Sustained ventricular tachycardias were the only exception, showing low heterogeneity (I² = 0.00%) and low pooled prevalence (0.2%). Overall, the prevalence of non-AF incidental findings during continuous ambulatory ECG screening in AF-free primary care and community-based cohorts varied widely, largely reflecting differences in definitions and reporting practices. This highlights the need for uniform reporting and further research into the prevalence and clinical relevance of these findings.

Background: Coronary revascularization is frequently undertaken to reduce ischemia in patients with ischemic left ventricular (LV) dysfunction. Whether revascularization modulates the substrate for ventricular arrhythmia is unclear.

Objective: The study aimed to assess the effects of revascularization on arrhythmic substrate in ischemic LV dysfunction and the association of the latter with changes in ischemia and scar.

Methods: Patients were enrolled if they had a LV ejection fraction (LVEF) ≤40%, extensive coronary disease (British Cardiovascular Intervention Society jeopardy score >6/12) and were scheduled to undergo percutaneous coronary intervention or coronary artery bypass surgery. Scar and ischemic burden were assessed via stress-perfusion cardiac magnetic resonance, calculated as a percentage of total LV myocardial volume. Arrhythmic substrate was characterized by non-invasive electrocardiographic imaging metrics, primarily LV activation recovery interval (ARI). Electrocardiographic imaging and perfusion cardiac magnetic resonance were repeated 3 months after revascularization. The primary outcome was change in LV ARI dispersion.

Results: Of 30 patients (age 67 ± 10 years, 87% male, LVEF 29 ± 7%), 12 (40%) underwent coronary artery bypass surgery, 18 (60%) had percutaneous coronary intervention. Following revascularization, LVEF increased (+8 ± 8%), ischemic burden reduced (-34 ± 24%), P < .01) and scar burden was unchanged. Mean LV ARI dispersion was unchanged; however, individual changes in LV ARI dispersion correlated with individual changes in ischemic burden (r = 0.51, P < .01). LV volumes and scar burden at baseline and change in indexed LV end-systolic volume and ischemia predicted improvement.

Conclusion: Arrhythmic substrate correlated with scar burden and was unaltered by revascularization in this cohort. There was marked heterogeneity in residual ischemia which correlated with residual arrhythmic substrate. Further work is needed to personalize risk stratification in relation to ischemia reduction and residual arrhythmic risk.