UNASSIGNED: Few large-scale, real-world studies have compared the efficacy and safety of non-antivitamin K anticoagulants (NOACs) with that of warfarin in catheter ablation (CA) for atrial fibrillation (AF).
UNASSIGNED: This retrospective, cross-sectional study used a nationwide administrative claims database, to compare complication-incidence rates following CA for AF between NOAC-treated patients and warfarin-treated matched cohorts in the real-world. Among the 32,797,540 records between June 2011 and August 2020 from 426 hospitals, 41,347 patients (38,065 on NOACs and 3,282 on Warfarin) were considered eligible. After performing propensity matching, 6,564 patients (3,282 per group) were analyzed.
UNASSIGNED: The overall complication incidence was significantly lower in the NOACs group than in the warfarin group (2.3 % vs. 4.0 %; P < 0.001, odds ratio [OR]: 0.55, 95 % confidence interval [CI]: 0.41-0.74). Although no significant differences in the incidence of cardiac tamponade (1.0 % vs. 1.1 %; P = 0.90, OR: 0.97, 95 % CI: 0.60-1.56) and major bleeding (0.6 % vs. 0.7 %; P = 0.54, OR: 0.83, 95 % CI: 0.44-1.52) were noted, blood transfusion requirements (0.6 % vs. 1.2 %; P = 0.02, OR: 0.52, 95 % CI: 0.30-0.88) and vascular complications (0.2 % vs. 0.5 %; P = 0.02, OR: 0.33, 95 % CI: 0.12-0.79) were significantly lower in the NOACs group than in the warfarin group. Furthermore, the thromboembolic event incidence was significantly lower in the NOACs group than in the warfarin group (0.5 % vs. 1.2 %; P < 0.001, OR: 0.36, 95 % CI: 0.19-0.64).
UNASSIGNED: NOACs should be considered as a first-line therapy for periprocedural anticoagulation in patients undergoing CA for AF.

UNASSIGNED: The relationship between atrial fibrillation (AF) and heart failure with depressed ejection fraction (EF) is complex. AF-related tachycardia-mediated cardiomyopathy (TMC) can lead to worsening EF and clinical heart failure. We sought to determine whether a hybrid team ablation approach (HA) can be performed safely and restore normal sinus rhythm in patients with TMC and heart failure and to delineate the effect on heart failure.
UNASSIGNED: We retrospectively analyzed patients with nonparoxysmal (ie, persistent and long-standing persistent) AF-related TMC with depressed left ventricular EF (LVEF ≤40%) and heart failure (New York Heart Association [NYHA] class ≥2) who underwent HA between 2013 and 2018 and had at least 1 year of follow-up. Pre-HA and post-HA echocardiograms were compared for LVEF and left atrial (LA) size. Rhythm success was defined as <30 seconds in AF/atrial flutter/atrial tachycardia without class I or III antiarrhythmic drugs. Results are expressed as mean ± SD and 95% confidence interval (CI) of the mean.
UNASSIGNED: Forty patients met the criteria for inclusion in our analysis. The mean patient age was 67 ± 9.4 years. The majority of patients had long-standing persistent AF (26 of 40; 65%), and the remainder had persistent AF (14 of 40; 35%). All patients had NYHA class II or worse heart failure (NYHA class II, 36 of 40 [90%]; NYHA class III, 4 of 40 [10%]). The mean time in AF pre-HA was 5.6 ± 6.7 years. All patients received both HA stages. No deaths or strokes occurred within 30 days. Three new permanent pacemakers (7.5%) were placed. Rhythm success was achieved in >60% of patients during a mean 3.5 ± 1.9 years of follow-up. LVEF improved significantly by 12.0% ± 12.5% (95% CI, 7.85%-16.0%; P < .0001), and mean LA size decreased significantly by 0.40 cm ± 0.85 cm (95% CI, 0.69-0.12 cm; P < .01), with a mean of 3.0 ± 1.5 years between pre-HA and post-HA echocardiography. NYHA class improved significantly after HA (mean pre-HA NYHA class, 2.1 ± 0.3 [95% CI, 2.0-2.2]; mean post-HA NYHA class, 1.5 ± 0.6 [95% CI, 1.3-1.7]; P < .0001).
UNASSIGNED: Thoracoscopic HA of AF in selected patients with TMC heart failure is safe and can result in rhythm success with structural heart changes, including improvements in LVEF and LA size.

UNASSIGNED: A novel catheter technology (direct sense, DS) enables periprocedural local impedance (LI) measurement for estimation of tissue contact during radiofrequency ablation (RFA) for real-time assessment of lesion generation. This measure reflects specific local myocardial conduction properties in contrast to the established global impedance (GI) using a neutral body electrode. Our study aimed to assess representative LI values for the cardiac chambers, to evaluate LI drop in response to RF delivery and to compare those values to established GI measures in patients undergoing RFA procedures.
UNASSIGNED: Seventy-three patients undergoing RFA with the DS technology were included. Within the cardiac chambers, baseline LI was significantly different, with the highest values in the left atrium (LA 107.5 ± 14.3 Ω; RV 104.6 Ω ± 12.9 Ω; LV 100.7 Ω ± 11.7 Ω, and RA 100.5 Ω ± 13.4 Ω). Baseline LI was positively correlated to the corresponding LI drop during RF delivery (R2 = 0.26, p = 0.01) representing a promising surrogate of lesion generation. The observed mean LI drop (15.6 ± 9.5 Ω) was threefold higher as GI drop (4.9 ± 7.4 Ω), p < 0.01. We evaluated the clinical outcome in a subgroup of patients undergoing DS-guided pulmonary vein isolation, which was comparable regarding arrhythmia recurrence to a conventional ablation cohort (57 % vs 50 %, p = 0.2).
UNASSIGNED: We provide detailed information on LI measures in electrophysiological procedures with significant differences within the cardiac chambers highlighting that RFA-related LI drop can serve as a promising surrogate for real-time assessment of lesion generation. Guiding the electrophysiologist in RFA procedures, this additional information promises to improve safety profile and success rates in the interventional treatment of arrhythmias.

A 10-year-old girl experienced cardiac failure due to atrial tachycardia originating from a left atrial appendage. Surgical appendectomy was done after a recurrence of the atrial tachycardia just after the first attempt at catheter ablation. A second ablation attempt was avoided because of the risk of cardiac perforation. (Level of Difficulty: Intermediate.).

We present a case of persistent dual AV node conduction during AV node reentry tachycardia as a new clinical manifestation of 2-for-1 AV node conduction. The interpretation of the complex physiology ponders the possibility of an accessory pathway mediated atrioventricular reentry existing with more ventricular than atrial events.

Focal atrial tachycardia arising from the right atrial appendage (RAAT) may be misdiagnosed as sinus tachycardia. The electrocardiogram from this case demonstrates a negative notched P-wave in leads V1 and V2 during RAAT compared with a beat of sinus rhythm. RAAT was confirmed and eliminated with mapping and ablation. (Level of Difficulty: Advanced.).

A 12-lead electrocardiogram of a regular narrow complex tachycardia with electrocardiographic characteristics used to help elucidate the arrhythmia mechanism. (Level of Difficulty: Intermediate.).

Primary cardiac angiosarcomas are rare malignant tumors with a very poor prognosis. We present a case of a 48-year-old man with no previous cardiac history who developed an incessant focal atrial tachycardia complicated by tachycardia-mediated cardiomyopathy as a consequence of cardiac angiosarcoma. (Level of Difficulty: Beginner.).

At 22 years following heart transplantation, a patient presented with incessant atrial flutter. During electrophysiologic study, 2 simultaneous atrial arrhythmias were mapped, 1 from the donor and 1 from the recipient\'s heart. High-density mapping allowed for rapid identification of electrically abnormal areas, which were successfully ablated, thus restoring sinus rhythm. (Level of Difficulty: Advanced.).

UNASSIGNED: Automated electrocardiogram (ECG) interpretations may be erroneous, and lead to erroneous overreads, including for atrial fibrillation (AF). We compared the accuracy of the first version of a new deep neural network 12-Lead ECG algorithm (Cardiologs®) to the conventional Veritas algorithm in interpretation of AF.
UNASSIGNED: 24,123 consecutive 12-lead ECGs recorded over 6 months were interpreted by 1) the Veritas® algorithm, 2) physicians who overread Veritas® (Veritas® + physician), and 3) Cardiologs® algorithm. We randomly selected 500 out of 858 ECGs with a diagnosis of AF according to either algorithm, then compared the algorithms\' interpretations, and Veritas® + physician, with expert interpretation. To assess sensitivity for AF, we analyzed a separate database of 1473 randomly selected ECGs interpreted by both algorithms and by blinded experts.
UNASSIGNED: Among the 500 ECGs selected, 399 had a final classification of AF; 101 (20.2%) had ≥1 false positive automated interpretation. Accuracy of Cardiologs® (91.2%; CI: 82.4-94.4) was higher than Veritas® (80.2%; CI: 76.5-83.5) (p < 0.0001), and equal to Veritas® + physician (90.0%, CI:87.1-92.3) (p = 0.12). When Veritas® was incorrect, accuracy of Veritas® + physician was only 62% (CI 52-71); among those ECGs, Cardiologs® accuracy was 90% (CI: 82-94; p < 0.0001). The second database had 39 AF cases; sensitivity was 92% vs. 87% (p = 0.46) and specificity was 99.5% vs. 98.7% (p = 0.03) for Cardiologs® and Veritas® respectively.
UNASSIGNED: Cardiologs® 12-lead ECG algorithm improves the interpretation of atrial fibrillation.