Circulation. Arrhythmia and electrophysiology最新文献

Background: Pulsed field ablation (PFA) is a promising treatment for atrial fibrillation. We report 1-year freedom from atrial arrhythmia outcomes using monopolar PFA delivered through 3 commercial, contact force-sensing focal catheters.

Methods: ECLIPSE AF (Safety & Clinical Performance Study of Catheter Ablation With the Centauri System for Patients With Atrial Fibrillation; NCT04523545) was a prospective, single-arm, multicenter study evaluating acute and chronic safety and performance using the CENTAURI system to deliver focal PFA with TactiCath SE, StablePoint, and ThermoCool ST. Patients with paroxysmal or persistent atrial fibrillation underwent pulmonary vein (PV) isolation under deep sedation or general anesthesia and returned for remapping at 90 days to evaluate chronic durability. Freedom from atrial arrhythmia was evaluated continuously through 12 months using standard rhythm monitoring for symptomatic episodes and 24-hour Holter at 6 and 12 months.

Results: Eighty-two patients (74% male, 51.2% paroxysmal, and 58.5% deep sedation) were treated. PV isolation was achieved in 100% of targeted veins (322/322) with first-pass isolation in 92.2% (297/322). There were 4 primary safety events in 4 patients (4.9%, 4/82); 1 nonembolic stroke due to exacerbated cardiac tamponade secondary to catheter perforation and 3 hemorrhagic vascular access complications. There were no incidences of adverse event fistula, diaphragmatic paralysis, myocardial infarction, pericarditis, thromboembolism, PV stenosis, transient ischemic attack, or death. Eighty patients (98%) underwent remapping. Optimized PFA cohorts 3, 4, and 5 showed per-patient isolation rates of 60%, 73%, and 81% and per-PV isolation rates of 84%, 90%, and 92%, respectively. One-year freedom from atrial arrhythmia was 80.2% (95% CI, 69.7%-87.4%) for the entire patient sample, including 41 patients who underwent repeat focal PFA with the CENTAURI system at remapping.

Conclusions: This study demonstrated that optimization of focal PFA with 3 contact force-sensing, solid-tip ablation catheters resulted in the progressive improvement of PV isolation durability at 3-month remapping and high freedom from atrial arrhythmia survival rates, providing a promising focal PFA treatment option integrated with current ablation workflows.

Complex ventricular tachycardias involving the fascicular system (fascicular ventricular tachycardias [FVTs]) can be challenging. In this review, we describe our approach to the diagnosis and ablation of these arrhythmias with 10 illustrative cases that involve (1) differentiation from supraventricular tachycardia; (2) assessment for atypical bundle branch reentry and other interfascicular FVTs; (3) examination of P1/P2 activation sequences in sinus rhythm, pacing, and tachycardia; and (4) entrainment techniques to establish the tachycardia mechanism and aid circuit localization. To summarize, 5 cases had prior ablation with 2 previously misdiagnosed as supraventricular tachycardia. A short His-ventricular interval supported ventricular tachycardia. Atrial stimulation could initiate and entrain 4 FVTs. P1 potentials were recorded in all cases of left posterior FVT. Entrainment at P1 and P1 to P2 connection sites at the mid-septal region, and the postablation emergence of a late P1 with decremental properties, is consistent with the left septal fascicle being the slowly conducting, retrograde limb of the left posterior FVT circuit. Ablation targeting the mid-septal left septal fascicle and P1 to P2 connection sites successfully eliminated left posterior FVT. Right ventricular apical pacing was useful in differentiating bundle branch reentry and focal FVTs from reentrant FVTs. Two cases exhibited bundle branch reentry and other interfascicular FVTs. Three cases were postinfarct FVTs involving the LPF, where pacing and entrainment at sites of conduction system potentials were able to localize sites critical for ablation, in contrast to previously unsuccessful substrate modification. In conclusion, several ventricular tachycardia mechanisms involving the fascicular system can occur in both structurally normal and abnormal hearts. A high index of suspicion is required given their rarity and potential for misdiagnosis. Once identified, we emphasize a structured approach to the diagnosis and management of FVTs to confirm the mechanism and localize suitable ablation targets involving careful recording of conduction system potentials and pacing/entrainment maneuvers.

Background: Brugada syndrome (BrS) is associated with ventricular fibrillation (VF). Different VF mechanisms have been described, and repolarization gradients were associated with VF in a BrS model. The aim of this study is to map VF in BrS with ECG imaging. Furthermore, spatial correlation between sinus rhythm maps and VF maps was evaluated.

Methods: Inclusion criteria were (1) BrS diagnosis and (2) VF mapped with ECG imaging during right ventricle outflow tract ablation. VF mechanism was classified into (1) rotational, (2) focal, and (3) irregular. For comparison, 6 controls were enrolled. The following sinus rhythm maps were performed: activation, recovery time, and activation-recovery interval time. Spatial overlap between steep repolarization gradients (cliffs) at recovery time and activation-recovery interval time maps and initiating VF rotational activity was evaluated with photogrammetry.

Results: A total of 28 VF maps in 21 patients with BrS were analyzed. In the first ≈7 seconds of VF, rotational, focal, and irregular mechanisms were found. In 19 patients with BrS (90.5%) and none of the controls, a right ventricle outflow tract repolarization cliff only was found. In all these patients, the singularity point of the first initiating rotational VF activity spatially overlapped with the right ventricle outflow tract cliff. Abolition of right ventricle outflow tract repolarization cliffs was confirmed in all but 2 patients (94.3%). In one patient with recurrence, VF was mapped on the anterior right ventricle over a cliff that was not targeted at the first ablation procedure.

Conclusions: In patients with BrS, repolarization heterogeneity has a critical role in VF. Repolarization cliffs might be a therapeutic target in VF ablation.

Background: Pulsed field ablation (PFA) has gained attention in cardiac electrophysiology, but data on its application to paroxysmal supraventricular tachycardia are limited. This study aimed to assess the feasibility and safety of PFA and its combination with radiofrequency ablation for treating paroxysmal supraventricular tachycardia.

Methods: A prospective, multicenter, single-arm study was conducted across 8 centers in China. Patients with atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia, or Wolff-Parkinson-White syndrome underwent ablation using a focal point dual-mode PFA/radiofrequency ablation catheter. PFA was used to achieve acute ablation success, with consolidation using PFA for atrioventricular nodal reentrant tachycardia or near-His accessory pathways and radiofrequency ablation for far-His accessory pathways. Primary and secondary end points were acute ablation success and 180-day follow-up success, respectively.

Results: A total of 158 patients (77 with atrioventricular nodal reentrant tachycardia, 63 with atrioventricular reentrant tachycardia, 16 with Wolff-Parkinson-White, and 2 with both atrioventricular nodal reentrant tachycardia and atrioventricular reentrant tachycardia) completed the trial. Acute ablation was successful in 157 patients (99.37%). The skin-to-skin procedure time was 89.9±35.5 min. The median number of PFA discharges was 12 (8-19) with a median effective PFA discharge time of 4.6 (3.2-6.4) ms. Five patients (4 with atrioventricular reentrant tachycardia and 1 with Wolff-Parkinson-White syndrome) experienced paroxysmal supraventricular tachycardia recurrence during the 180-day follow-up period. One patient had a transient first-degree atrioventricular block resolving in 12 hours, and one patient had a transient third-degree atrioventricular block resolving in 24 hours. No permanent atrioventricular block or other adverse events occurred during the ablation procedure or 180-day follow-up period.

Conclusions: PFA demonstrated the feasibility of the treatment of SVT. Reversible first- and third-degree atrioventricular blocks were observed following ablation in one patient each. The preliminary results indicated the safety and feasibility of a combination of PFA and radiofrequency ablation treatment for atrioventricular accessory pathways although it is impossible to determine the relative contribution of PFA.

Background: Atrial fibrillation (AF) recurrence is common after catheter ablation. Pulmonary vein (PV) isolation is the cornerstone of AF ablation, but PV remodeling has been associated with the risk of AF recurrence. We aimed to evaluate whether artificial intelligence-based morphological features of primary and secondary PV branches on computed tomography images are associated with AF recurrence post-ablation.

Methods: Two artificial intelligence models were trained for the segmentation of computed tomography images, enabling the isolation of PV branches. Patients from Cleveland Clinic (N=135) and Vanderbilt University (N=594) were combined and divided into 2 sets for training and cross-validation (D₁, n=218) and internal testing (D₂, n=511). An independent validation set (D₃, N=80) was obtained from University Hospitals of Cleveland. We extracted 48 fractal-based and 12 shape-based radiomic features from primary and secondary PV branches of patients with AF recurrence (AF+) and without recurrence after catheter ablation of AF (AF-). To predict AFrecurrence, 3 Gradient Boosting classification models based on significant features from primary (M_p), secondary (M_s), and combined (M_c) PV branches were built.

Results: Features relating to primary PVs were found to be associated with AF recurrence. The M_p classifier achieved area under the curve values of 0.73, 0.71, and 0.70 across the 3 datasets. AF+ cases exhibited greater surface complexity in their primary PV area, as evidenced by higher fractal dimension values compared with AF- cases. The M_s classifier results revealed a weaker association with AF+, suggesting higher relevance to AF recurrence post-ablation from primary PV branch morphology.

Conclusions: This largest multi-institutional study to date revealed associations between artificial intelligence-extracted morphological features of the primary PV branches with AF recurrence in 809 patients from 3 sites. Future work will focus on enhancing the predictive ability of the classifier by integrating clinical, structural, and morphological features, including left atrial appendage and left atrium-related characteristics.

Background: The pentaspline pulsed field ablation catheter achieves pulmonary vein isolation using 8 stacked, pose-specific applications with rotation. The morphology of pose-specific, single or double applications has not been described.

Methods: One or 2 applications were delivered to select veins and discrete atrial and ventricular sites in 9 swine. General anesthesia with neuromuscular paralysis ensured a stable position. Preablation, postablation, and serial intraprocedural mappings were performed to characterize electrical vein isolation and dynamic voltage changes. Upon euthanize at 2 days (7 of 9 swine), hearts were subject to pathological examination.

Results: Six superior vena cavae received single or double applications in basket pose without rotation. Despite incomplete dosing, acute electrical isolation occurred in 4 of 6 veins. None recovered conduction over 40 minutes, but all 3 isolated veins that were remapped at 2 days had reconnected. Lesions were linear (15-16 mm) with gaps and significantly wider with double versus single applications (8.2±2.8 versus 6.1±2.0 mm; P=0.02). Similar lesions, with acute isolation and subsequent reconnection, were observed in 3 of 4 ablated pulmonary veins. Double flower pose applications to the posterior atrium created wide (≈40×30 mm) confluent lesions, whereas single applications resulted in curvilinear lesions with variable gaps. Flower pose lesions (single or double) in the right ventricle were flower-shaped, linear with gaps, and with depths up to ≈5 mm.

Conclusions: The pentaspline catheter in the basket pose creates perivenous linear lesions with gaps. Single applications in flower pose generate narrow linear lesions with variable gaps, whereas double applications result in wide, confluent lesions.