Circulation. Arrhythmia and electrophysiology最新文献

Background: Atrial fibrillation (AF) is a common cardiac arrhythmia. Its detection rates vary significantly across ethnic groups, impacting epidemiological and clinical outcomes. We aim to explore ethnic differences in self-reported versus hospital-reported AF using the MESA (Multi-Ethnic Study of Atherosclerosis).

Methods: Six thousand seven hundred seventy-five adults aged 45 to 84 years, free from baseline AF and major cardiovascular events, were monitored over 8.4 years (2000-2012) across 6 US locations. AF incidence was measured via hospital discharge International Classification of Diseases codes and self-reported data, validated by follow-up questionnaires. AF incidence per 1000 person-years was assessed by ethnic group and reporting method. Incidence rate ratios and adjusted hazard ratios were calculated with White participants as the referent group.

Results: The study comprised 2611 White, 800 Chinese, 1485 Hispanic, and 1879 Black participants, with a mean age of 62.15 (10.24) years; 47.1% were male. Chinese had significantly lower incidence rate ratio (0.40 [95% CI, 0.19-0.75]; P=0.009) for AF reported only during hospitalization, whereas Hispanic group had significantly lower incidence rate ratio (0.29 [95% CI, 0.15-0.51]; P<0.001) for AF only via self-reporting. The combined overall reported AF incidence was 6.4%, or 7.72 per 1000 person-years, highest in the White group (10.69 per 1000 person-years) and lower in in Chinese (6.43 [95% CI, 4.61-8.71]; P=0.003), Hispanics (4.79 [95% CI, 3.61-6.24]; P<0.001), and Blacks (6.39 [95% CI, 5.16-7.84]; P<0.001).

Conclusions: The reported incidence of AF varies with the inclusion of self-reported data and across ethnic and racial groups. The inclusion of self-reported data increased the reported incidence of AF the most among Chinese individuals and the least among Hispanic participants. In the MESA study, the inclusion of self-reported data reveals heterogeneous changes across ethnic and racial groups, which may be due to differences in true incidence, methods of ascertainment, symptom perception, or health care access, and deserves further exploration.

Pulsed field ablation (PFA) has been developed as a largely nonthermal ablation technology with a unique biophysical profile to treat atrial fibrillation. Existing evidence has shown that PFA offers a safe and efficient atrial fibrillation ablation procedure. Among different PFA technologies, the pentaspline FARAPULSE system has been the most extensively used and investigated; however, notable variability exists in workflow, fluoroscopy time, and lesion durability. While innovations such as 3-dimensional electroanatomic mapping systems and intracardiac echocardiography can enhance procedural precision in catheter ablation, fluoroscopy remains the primary imaging modality for guiding pentaspline PFA in many electrophysiology labs worldwide. This is particularly true in centers where limitations in cost, infrastructure, or training may preclude the routine use of advanced imaging technologies. This article summarizes general practical considerations and presents a primarily fluoroscopy-based, refined workflow developed by a group of experts. The goal is to provide a procedural foundation and practical guide for using the pentaspline FARAPULSE PFA system in atrial fibrillation ablation procedures. Developing a fluoroscopy-based practical guide would: (1) Democratize access to PFA technology, enabling safe and effective implementation across a broader range of clinical settings, including those without intracardiac echocardiography or 3-dimensional mapping support; (2) Reduce procedural heterogeneity by offering reproducible best practices; (3) Facilitate meaningful intercenter comparisons of procedural efficacy and safety, aiding in the identification of optimal approaches and improving the quality of clinical data for ongoing research, registries, and real-world performance monitoring of PFA technologies; and (4) Ultimately improve patient outcomes through standardized, accessible, and evidence-based practices.

Background: Cryoballoon pulmonary vein isolation has become an established treatment for atrial fibrillation (AF). However, data on long-term outcomes beyond 5 years are scarce. This prospective analysis aimed to evaluate the long-term outcome after cryoballoon pulmonary vein isolation.

Methods: Data from consecutive patients treated with cryoballoon pulmonary vein isolation for symptomatic AF between 2012 and 2018 in 13 institutions were analyzed. Patients with ≥5-year follow-up after the index procedure were included. Arrhythmia recurrence was defined as AF or atrial tachycardia lasting >30 seconds beyond a 3-month blanking period.

Results: A total of 1330 patients were enrolled (28.4% female patients, mean age was 60.1±10.5 years). Patients with paroxysmal AF accounted for 73.1%; the median history of AF was 36.0 (13.0-75.0) months. The rate of AF/atrial tachycardia recurrences progressively increased over time (event rate: 52.5% [49.4%-55.8%] at 8-year follow-up). A low incidence of progression to permanent AF was seen in the entire cohort (7.0%). Importantly, 15.7% of patients underwent a redo ablation for AF during follow-up; in 45.9% of these cases, all PVs were isolated at the redo procedure, with a median number of PVs isolated after the index procedure being 3 (1-4) veins. Independent predictors of arrhythmia recurrences were AF type (persistent AF: hazard ratio, 1.36 [95% CI, 1.14-1.62]; P<0.001) and chronic kidney disease (hazard ratio, 1.77 [95% CI, 1.12-2.81]; P=0.016) in multivariate analysis.

Conclusions: Cryoballoon pulmonary vein isolation as the index procedure for AF ablation resulted in a favorable long-term outcome in patients with symptomatic AF, with limited progression towards permanent AF during follow-up. Persistent AF was the strongest predictor of recurrences at long-term follow-up.

Background: Blocking a line depends not only on the ablation but also on the validation technique. We sought to compare the performance of different pacing modes for roof line validation.

Methods: Fifty consecutive patients underwent atrial fibrillation ablation, which included a roof line and a floor line. Floor line block was mandatory for clear evaluation of the roof line, the block of which was demonstrated by a box isolation of the dome. Before floor line creation, first-pass roof line evaluation was based on high-density mapping while pacing from either: (1) the left appendage; (2) just above the line; or (3) with an overlapping multispline catheter.

Results: Roof line mapping was feasible in all patients (100%) during left appendage and nearby pacing, and in 45 (90%) patients during overlap pacing. Left appendage pacing sensitivity for true gaps was significantly lower than nearby (48% versus 97%; P<0.001) and overlap (48% versus 93%; P<0.001) pacing. Left appendage pacing negative predictive value for true block was significantly lower than nearby (50% versus 94%; P=0.001) and overlap (50% versus 89%; P=0.004) pacing. Double potentials during left appendage pacing were shorter than during nearby pacing (63±20 ms versus 103±22 ms; P<0.001). In 1 patient, a slow conduction gap was unmasked only after floor line block. Final box isolation of the dome was achieved in 47 (94%) patients.

Conclusions: The longer the activation delay from one side of a line to the other, the greater the chance to unmask a slow conduction gap across the line. Nearby pacing thus better identifies roof line gaps than left appendage pacing. Overlap pacing offers a simple and fast alternative with similar performance.

Background: Mitral isthmus (MI) gap conduction is common despite ethanol infusion into the vein of Marshall (EI-VOM) and endocardial ablation of the MI. This study aimed to investigate the characteristics of electrograms of the distal coronary sinus (CSd) to guide the identification of the gap location in the MI.

Methods: A total of 187 patients who underwent EI-VOM and MI ablation were included in the study. After routine completion of EI-VOM and endocardial MI ablation, the characteristics of the electrogram in the CSd during left atrial appendage pacing were analyzed in unblocked MI conduction.

Results: Among the 187 patients, 43.3% (81/187) had unblocked MI following EI-VOM and linear lesion creation in the endocardium. In patients with unblocked MI, 84.0% (68/81) showed double potentials in the CSd during left atrial appendage pacing, among whom 80.9% (55/68) presented with an earlier high-frequency near-field potential followed by a low-frequency far-field potential, suggesting an epicardial gap, whereas 19.1% (13/68) presented with a far-field potential followed by a near-field potential, suggesting an endocardial gap. In patients with single potentials in the CSd (16.0%, n=13), simple activation mapping of the endocardium and CSd revealed the gap location. Intracoronary sinus ablation was necessary in 77.8% (63/81) of the patients, with a mean of 1.3±1.7 sites and 1.1±0.4 minutes of ablation. Eventually, 95.7% (179/187) of the patients achieved MI block. These findings were confirmed in an external validation cohort, which demonstrated the effectiveness and efficiency of CSd potential-guided gap identification.

Conclusions: The characteristics of the electrograms in the CSd could aid in the prompt identification of the gap location(s) in the MI in patients with unblocked MI conduction.

Background: Reentry (macro or localized) is historically described as multiple pathways that are separated by barriers (either anatomic or functional) and involve active and passive loops (identified by electro-anatomic and entrainment mapping, EAM/ETM). Some reentrant atrial tachycardia (AT) cases are characterized by challenging activation patterns and unexpected ablation responses. A recent translational study, focusing on topology (TOP) and the role of boundaries, suggests that thinking topology within EAM/ETM might offer extra control during mapping and ablation of reentrant AT. We aimed to propose and prospectively validate a workflow (EAM/ETM+TOP) in which we integrate topological thinking within an EAM/ETM workflow for mapping and ablation of left-sided (left atrium) AT.

Methods: The integrated workflow was performed in 88 left atrium reentrant AT cases. After EAM/ETM, the number of loops and potential ablation strategy were verified against the number of critical and noncritical boundaries (critical boundary [CB], non-CB). Linear radiofrequency lesions were deployed to connect both CBs, preferably by one direct CB-CB line.

Results: EAM/ETM+TOP-based mapping was feasible in all cases and led to a diagnosis of a 2B topology with single-loop activation in 33 cases and a≥3B topology with dual-loop activation in 55 cases. In 87 out of 88 cases, subsequent ablation via a direct CB-CB approach (n=75), an indirect CB-non-CB-CB (n=9), or an indirect CB-non-CB-non-CB-CB approach (n=3) led to successful termination of AT. No unexpected changes in tachycardia cycle length occurred. After a median follow-up of 356 (inter-quartile range, 228-537) days, 16 patients experienced recurrence of AT (18%).

Conclusions: Thinking topology within an EAM/ETM workflow may offer extra control during mapping and ablation of left-sided reentrant AT.

Background: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by α-Gal A (α-galactosidase A) deficiency, resulting in multiorgan accumulation of sphingolipid, namely globotriaosylceramide. This triggers ventricular myocardial hypertrophy, fibrosis, and inflammation, driving arrhythmia and sudden death. Atrial fibrillation is common, yet the cellular mechanisms accounting for this are unknown.

Methods: To address this, we conducted ECG analysis from a large cohort of 115 adults with FD at varying cardiomyopathy stages. ECG P-wave characteristics were compared with non-FD controls. Cellular contractile and electrophysiological function were examined in a novel atrial cellular FD model developed and imputed into in silico atrial models to provide insight into mechanisms of arrhythmia. Induced pluripotent stem cells were genome-edited using Clustered Regularly Interspaced Short Palindromic Repeats-Cas9 to introduce the GLA p.N215S variant and differentiated into induced pluripotent stem cell-derived atrial cardiomyocytes (iPSC-CMs). Contraction, calcium handling, and electrophysiology experiments were conducted. Bi-atrial in silico models were developed with cellular changes as in GLA p.N215S iPSC-CMs.

Results: ECG analysis demonstrated P-wave duration and PQ interval shortening in FD adults before the onset of cardiomyopathy. Patients with FD exhibited a higher incidence of premature atrial contractions and increased risk of atrial fibrillation compared with healthy controls. GLA p.N215S iPSC-CMs were deficient in α-Gal A and exhibited globotriaosylceramide accumulation. Atrial GLA p.N215S iPSC-CMs demonstrated a more positive diastolic membrane potential, faster action potential upstroke velocity, greater incidence of delayed afterdepolarizations, greater contraction force, and alterations in calcium handling compared with wild-type iPSC-CMs. Simulations with these changes in the in silico models resulted in similar P-wave morphology changes to those seen in early FD cardiomyopathy and increased atrial fibrillation vulnerability.

Conclusions: These findings provide novel insights into underpinning mechanisms for atrial arrhythmia and a rationale for early P-wave changes in FD. These may be targeted to develop therapeutic strategies to reduce the arrhythmic burden in FD.

Background: Accurate delineation of scar patterns is valuable for guiding catheter ablation of ventricular tachycardia. We hypothesized that scar and its pattern of distribution can be determined from intracardiac electrograms using computational signal processing and that further improvements in classification can be achieved with a convolutional neural network.

Methods: A total of 5 sheep underwent anteroseptal infarction (plus 1 healthy control) with electroanatomic mapping (129±12 days post-infarct). A whole-heart histological model of the postinfarction scar was created and coregistered to ventricular electrograms. Electrograms were matched to scar pattern categories; no scar, at least endocardial scar: at least intramural scar (intramural scar sparing the endocardium), or epicardial-only scar (epicardial scar sparing the endocardium/intramural space). A suite of signal-processing features was extracted from bipolar electrograms. Furthermore, bipolar and unipolar electrograms were used to train a time series convolutional neural network (InceptionTime).

Results: A total of 11 551 electrograms were matched to 451 biopsies. Bipolar and unipolar voltage alone were poor classifiers of scar patterns. For each of the scar labels, 20 bipolar electrogram features (predominantly within the frequency domain) yielded an area under the curve of 0.815, 0.810, 0.704, and 0.681 to predict no scar, at least endocardial scar, at least intramural scar, and epicardial-only scar, respectively. Substantial improvement was achieved with a convolutional neural network trained on unipolar electrograms: areas under the curve and accuracy (averaged across wavefronts) were 0.977 and 0.929 for no scar, 0.970 and 0.919 for at least endocardial scar, 0.909 and 0.959 for at least intramural scar and 0.926 and 0.958 for epicardial-only scar.

Conclusions: Convolutional neural network-derived analysis of unipolar electrogram data has excellent predictive value for determination of scar patterns. Computational analyses of electrogram data beyond voltage and other time-domain features are necessary to improve the identification of arrhythmogenic sites in the ventricle.