Current Real-World Status of Off-Label Under- and Over-Dose of Direct Oral Anticoagulants After Atrial Fibrillation Ablation.

Background: Off-label under- and overdosing of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) is not uncommon in real-world practice.

Objective: This study aimed to identify efficacy and safety of off-label DOACs dose after AF ablation.

Methods: The RYOUMA registry was a prospective multicenter study of Japanese patients who underwent AF ablation between 2017 and 2018.

A Novel Wave-speed Mapping Method for Visualizing Accessory Pathways in Wolff-Parkinson-White Syndrome.

Introduction: Catheter ablation (CA) is the first-line treatment with a high success rate for patients with symptomatic Wolff-Parkinson-White syndrome, while three-dimensional (3D) mapping systems enable the identification of accessory pathways (APs). We aimed to develop a novel mapping method using wave-speed mapping (WSM) to determine AP locations and CA outcomes.

Methods And Results: This study included 19 patients diagnosed with atrioventricular (AV) reciprocating tachycardia.

Unidirectional reconnection of an inter-atrial epicardial connection with wide right atrial insertion site: a case report.

Background: The epicardial connections (ECs) via intercaval fibres connecting the right-sided pulmonary veins (PVs) and right atrium (RA) can preclude isolation of the right-sided PVs. Such ECs occasionally have a unidirectional conduction property.

Case Summary: A 62-year-old man was referred to our institution for catheter ablation of paroxysmal atrial fibrillation (PAF).

The benefits of ablation using TactiFlex compared with TactiCath in an ex vivo model: a face-to-face experimental comparison study.

Background: TactiFlex is a next-generation catheter that is being used increasingly in ablation-treatment strategies. The purpose of this study was to investigate the differences in ablation lesions when the ablation power, time, and perfusion flow are varied with TactiFlex and TactiCath catheters.

Methods: The TactiFlex and TactiCath catheters were contacted perpendicularly/obliquely/parallel to the swine myocardium at varying powers (30, 40, and 50 W), time points (10, 15, 20, 25, 30, and 40 s), and forces (5, 10, 15, 20, and 30 g); the depth, width, and area of each lesion were measured, and the number of steam pops that occurred was counted.

Prediction of heart failure events based on physiologic sensor data in HINODE defibrillator patients.

Aims: Hospitalizations are common in patients with heart failure and are associated with high mortality, readmission and economic burden. Detecting early signs of worsening heart failure may enable earlier intervention and reduce hospitalizations. The HeartLogic algorithm is designed to predict worsening heart failure using diagnostic data from multiple device sensors.

An inherited life-threatening arrhythmia model established by screening randomly mutagenized mice.

Inherited arrhythmia syndromes (IASs) can cause life-threatening arrhythmias and are responsible for a significant proportion of sudden cardiac deaths (SCDs). Despite progress in the development of devices to prevent SCDs, the precise molecular mechanisms that induce detrimental arrhythmias remain to be fully investigated, and more effective therapies are desirable. In the present study, we screened a large-scale randomly mutagenized mouse library by electrocardiography to establish a disease model of IASs and consequently found one pedigree that exhibited spontaneous ventricular arrhythmias (VAs) followed by SCD within 1 y after birth.

Impact of High-Voltage Device Implantation in Elderly Japanese Patients With Heart Failure as Primary Prevention - Post Hoc Analysis of HINODE.

Background: Despite an increased incidence of chronic heart failure (HF) and sudden cardiac death (SCD), the use of implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT) is much lower in Japan than in Western countries. The HF Indication and SCD Prevention Trial Japan (HINODE) prospectively assessed the mortality rate, appropriately treated ventricular arrhythmias (VA), and HF in Japanese patients with a higher risk of HF.

Methods and results: HINODE consisted of ICD, CRT-defibrillator (CRT-D), pacing, and non-device treatment cohorts.

Immediate pharmacotherapy intensification after cardiac resynchronization therapy: incidence, characteristics, and impact.

Aims: Cardiac resynchronization therapy (CRT) is an established treatment for drug-refractory heart failure (HF) in patients with left bundle branch block (LBBB). Acute haemodynamic improvement after CRT implantation may enable the intensification of HF medication soon thereafter. Immediate pharmacotherapy intensification (IPI) after CRT implantation achieves a synergetic effect, possibly leading to a better prognosis.

Late life-threatening arrhythmia in patients with Brugada syndrome: Results from long-term follow-up in a large Japanese cohort.

Introduction: Most patients with Brugada syndrome (BrS) are first diagnosed in their 40s, with sudden cardiac death (SCD) often occurring in their 50s. Ventricular fibrillation (VF) may occur in some patients with BrS despite having been asymptomatic for a long period. This study aimed to assess the incidence and risk factors for late life-threatening arrhythmias in patients with BrS.

Management of refractory intramural left ventricular summit ventricular arrhythmia: Acute success using bipolar radiofrequency catheter ablation with recurrence.

Bipolar radiofrequency catheter ablation (RFCA) is a novel strategy for refractory or recurrent ventricular arrhythmias (VAs) resistant to conventional ablation methods. Lesions created during bipolar RFCA are larger than those created during sequential unipolar ablation. We present a case of refractory LV summit VAs, which identified the origin using a 2.

Balloon surface temperature-controlled ablation using a second-generation radiofrequency HotBalloon: an in vivo feasibility study.

Aims: The first-generation radiofrequency HotBalloon (RHB) is a size-adjustable single-shot device used in atrial fibrillation. The energy output is determined by its central temperature and not by its balloon surface temperature (BST), thus limiting its efficacy and safety. Therefore, a second-generation RHB was developed to monitor BST and enable BST-controlled ablation.

Triggers of Ventricular Fibrillation in Patients With Inferolateral J-Wave Syndrome.

Background: There are few data on ventricular fibrillation (VF) initiation in patients with inferolateral J waves.

Objectives: This multicenter study investigated the characteristics of triggers initiating spontaneous VF in inferolateral J-wave syndrome.

Methods: A total of 31 patients (age 37 ± 14 years, 24 male) with spontaneous VF episodes associated with inferolateral J waves were evaluated to determine the origin and characteristics of triggers.

The R Wave Amplitude in Lead aVL Could Predict Successful Catheter Ablation of Ventricular Arrhythmias Originating below the His Bundle Region of the Right Ventricle.

Radiofrequency catheter ablation (RFCA) to treat ventricular arrhythmias (VAs) originating below the His bundle (HB) region of the right ventricular (RV) septum could impair the atrioventricular node conduction. This study aimed to clarify the parameters of the 12-lead electrocardiography that predict successful RFCA of VAs originating from this region. This study included 20 consecutive patients (13 men; mean age, 68 ± 7 years) with monomorphic VAs in whom the earliest ventricular activation during the VA was below the HB region of the RV septum.

Randomized crossover trial of 2-week Garment electrocardiogram with dry textile electrode to reveal instances of post-ablation recurrence of atrial fibrillation underdiagnosed during 24-hour Holter monitoring.

Background: Atrial fibrillation (AF) is the most common arrhythmia and often recurs despite catheter ablation. The recurrence of AF is often underdiagnosed by standard 24-hour electrocardiogram (ECG) because of its transient and silent nature. A garment-style ECG with a highly conductive textile electrode made of poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate)(PEDOTPSS) and nanofiber (Garment ECG) has been developed that can provide longer-term continuous monitoring.

Initial multicenter clinical experience with the first-generation endoscopic guided laser balloon in Japan.

Background: Isolation of the pulmonary veins (PVs) is the golden standard for atrial fibrillation (AF) ablation. To achieve a permanent PV isolation, the endoscopic guided HeartLight laser balloon system was invented. We analyzed the safety and efficacy of this laser balloon system.

Electrical, structural, and autonomic atrial remodeling underlies atrial fibrillation in inflammatory atrial cardiomyopathy.

Background: There is growing evidence indicating a close relationship between inflammation and atrial fibrillation (AF). Although underlying inflammatory atrial cardiomyopathy may contribute to the development of AF, the arrhythmogenic remodeling caused by atrial inflammation has not been elucidated in detail. Herein, we examined electrical, structural, and autonomic changes in the atria in a mouse model of autoimmune myocarditis.