Lesion characteristics of long application time ablation using unipolar half-normal saline irrigation and bipolar normal saline irrigation.

Introduction: Unipolar radiofrequency (RF) ablation using half-normal saline irrigation (UNIP-HNS) and bipolar RF ablation using normal saline irrigation (BIP-NS) are effective to treat arrhythmias from inside thick myocardium. However, differences between these two ablations when using a long application time had not fully been studied.

Methods: UNIP-HNS, BIP-NS and unipolar RF ablation using normal saline irrigation (UNIP-NS) were applied for 120 s (30 W and 20-g contact) to porcine endocardial wall (≧15.

Differences in coagulation responses to vascular injury between uninterrupted dabigatran and apixaban: A clinical prospective randomized study.

Background: The coagulation response during vascular injury with uninterrupted administration of direct oral anticoagulants has not been elucidated.

Objective: Our aim was to evaluate differences in coagulation responses after vascular injury between uninterrupted direct thrombin inhibitor and direct factor Xa inhibitor recipients.

Methods: Patients scheduled for catheter ablation for atrial fibrillation were randomly assigned to receive dabigatran or apixaban in this prospective, randomized, comparative, parallel-group study.

Predictors of long-term survival in Japanese patients with heart failure with reduced ejection fraction (HFrEF) treated with cardiac resynchronization therapy-defibrillators (CRT-D).

Background: Reports on the factors predicting long-term survival of CRT-D cases from Western countries are increasing, however, those from Asia including Japan are still sparse. We aimed to clarify the factors predicting long-term survival of Japanese CRT-D cases.

Methods: We retrospectively analyzed consecutive 133 patients who underwent CRT-D implantation between 2006 and 2021.

Clinical impact of nocturnal ventricular tachyarrythmias in electrical storm.

Background: The incidence of electrical storm (ES) is significantly higher during the daytime. However, the association between nocturnal ventricular tachyarrythmias during ES and prognosis remains unclear. Therefore, this study aimed to investigate the clinical characteristics and outcomes of ES with midnight ventricular tachyarrythmias.

Clinical impact of ECG changes on oversensing of subcutaneous implantable cardioverter-defibrillators.

Background: Inappropriate shocks delivered by subcutaneous implantable cardioverter-defibrillators (S-ICDs) are most frequently caused by cardiac oversensing. However, the predictors for oversensing of S-ICD remain unclear.

Objective: We aimed to investigate the predictors for oversensing of S-ICD, especially clinical impact of an electrocardiographic (ECG) change.

The Risk of Ventricular Tachyarrhythmias in Patients with Antimitochondrial Antibodies-Related Noncardiac Diseases.

Antimitochondrial antibodies (AMA) are serum autoantibodies specific to primary biliary cholangitis and are linked to myopathy and myocardial damage; however, the presence of AMA as a risk factor for ventricular tachyarrhythmias (VTs) has remained unknown. This study aimed to elucidate whether the presence of AMA-related noncardiac diseases indicates VTs risk.This cohort study enrolled 1,613 patients (883 females) who underwent AMA testing to assess noncardiac diseases.

Platypnea-orthodeoxia Syndrome Due to Right Ventricular Inflow Tract Obstruction Caused by an Elongated Ascending Aorta: Usefulness of Three-dimensional Cardiac Computed Tomography Imaging in the Sitting Position.

An 84-year-old woman presented with dyspnea in the sitting position. Platypnea-orthodeoxia syndrome (POS) was suspected based on arterial desaturation when her posture changed from the supine to the sitting position. Transesophageal echocardiography showed right-to-left shunting enhancement through a patent foramen ovale (PFO) in the sitting position.

Efficacy of antitachycardia pacing alert by remote monitoring of implantable cardioverter-defibrillators for out-of-hospital electrical storm.

Background: Remote monitoring (RM) has been shown to reduce all-cause mortality in patients with implantable cardioverter-defibrillators or cardiac resynchronization therapy defibrillators (ICD/CRT-D). Not all devices transmit an alert for antitachycardia pacing (ATP) therapy, and it is unknown whether differences of RM alert affect the outcomes of electrical storm (ES).

Methods: We enrolled 42 patients with ICD/CRT-D whose out-of-hospital ES were detected by RM between 2013 and 2020.

Progressive increase in activation delay during premature stimulation is related to ventricular fibrillation in Brugada syndrome.

Introduction: The local conduction delay has been deemed to play an important role in the perpetuation of ventricular fibrillation (VF) in Brugada syndrome (BrS). We evaluated the relationship between the activation delay during programmed stimulation and cardiac events in BrS patients.

Methods: This study included 47 consecutive BrS patients who underwent an electrophysiological study and received implantable cardiac defibrillator therapy.

J point elevation in high precordial leads associated with risk of ventricular fibrillation.

Introduction: The significance of high precordial electrocardiograms in idiopathic ventricular fibrillation (IVF) is unknown.

Method: This study included 50 consecutive patients (48 men; age, 42 ± 18 years) who had spontaneous ventricular fibrillation not linked to structural heart disease and received implantable cardiac defibrillator therapy. IVF was diagnosed in 35 patients and Brugada syndrome was diagnosed in other 15 patients.

Early repolarization and risk of lone atrial fibrillation.

Introduction: Early repolarization syndrome is a recently proposed condition characterized by an early repolarization pattern in the electrocardiogram (ECG) and ventricular fibrillation in the absence of structural heart abnormalities. Although some studies have suggested that early repolarization is associated with frequency of atrial fibrillation, the association of early repolarization with atrial fibrillation is not well known.

Hypothesis: Early repolarization indicates the substrate for atrial fibrillation in addition to that for ventricular fibrillation.