Subclinical sinus node dysfunction in patients with atrial fibrillation-Insight from ultrahigh-resolution mapping of human sinoatrial exits.

Background: Even a short duration of paroxysmal episodes of atrial fibrillation (AF) is associated with sinus node (SN) remodeling and a reduced SN reserve or dysfunction. The number of earliest atrial activation sites (EASs) during sinus rhythm decreases according to the decrease in the SN reserve.

Objective: We sought to evaluate the EASs during sinus rhythm using an ultrahigh-density mapping system.

Evaluation of cryoballoon pulmonary vein isolation lesions during the acute and chronic phases using a high-resolution mapping system.

Background: An acute cryothermal ablation lesion contains both reversible and irreversible elements. However, differences in lesions created with cryoballoon pulmonary vein isolation (PVI) between the acute and chronic phases have not been fully elucidated.

Methods: We retrospectively analyzed 23 consecutive patients with atrial fibrillation who underwent cryoballoon PVI during the initial procedure followed by a second ablation procedure.

Evaluation of interatrial conduction pattern after pulmonary vein isolation using an ultrahigh-resolution electroanatomical mapping system.

Interatrial conduction consists of various muscular bundles, including the Bachmann bundle. In this study, we investigated interatrial activation patterns using ultrahigh-resolution left atrial endocardial mapping. This study investigated 58 patients who underwent catheter ablation of atrial arrhythmia via an ultrahigh-resolution mapping system (Rhythmia) at our hospital from May 2020 to January 2021.

Conduction delay across the cavotricuspid isthmus block line caused by the gap near the inferior vena cava: the role of conduction block in the lower lateral right atrium.

The electrophysiological properties of the gap associated with the cavotricuspid isthmus (CTI) block line near the inferior vena cava (IVC) are not fully elucidated. Of 143 patients who underwent CTI block line ablation between September 2020 and April 2021, high-resolution CTI gap mapping was performed for 15 patients. Four patients were identified as having a gap near the IVC (IVC-side gap) despite wide double potentials (DPs) with > 90 ms intervals at the block line.

Early diastolic mitral regurgitation in left ventricular aneurysm.

Diastolic mitral regurgitation is a type of functional mitral regurgitation that develops via a reversal of the left atrioventricular pressure gradient during diastole. This study aimed to explore the mechanism underlying early diastolic mitral regurgitation (EDMR) in patients with left ventricular (LV) aneurysms after anterior myocardial infarction (AMI) by assessing the intraventricular pressure difference using vector flow mapping. We enrolled 23 consecutive patients with LV aneurysms (with and without EDMR) and 15 healthy men as controls.

Safety and durability of cavo-tricuspid isthmus linear ablation in the current era: Single-center 9-year experience from 1078 procedures.

Cavo-tricuspid isthmus (CTI) linear ablation is performed not only for atrial flutter (AFL) but empirically during atrial fibrillation (AF) ablation in real-world practice.  PURPOSE: We sought to evaluate the safety and durability of the CTI ablation.  METHODS: This retrospective study included 1078 consecutive patients who underwent a CTI ablation.

Premature ventricular contraction originating from the distal left anterior fascicle: The usefulness of a multipolar catheter with small electrodes in mapping presystolic Purkinje potential and pace mapping.

Mapping and localizing presystolic Purkinje potentials are crucial for determining the optimal ablation site for fascicular premature ventricular contractions (PVCs). Here we present a case of PVCs originating from the distal left anterior fascicle (LAF). Activation mapping using a multipolar catheter with small electrodes demonstrated early presystolic Purkinje potentials during the PVCs.

Ultra-high resolution mapping of reverse typical atrial flutter: electrophysiological properties of a right atrial posterior wall and interatrial septum activation pattern.

Purpose: We aimed to elucidate the right atrial posterior wall (RAPW) and interatrial septum (IAS) conduction pattern during reverse typical atrial flutter (clockwise AFL: CW-AFL).

Methods: This study included 30 patients who underwent catheter ablation of CW-AFL (n = 11) and counter-clockwise AFL (CCW-AFL; n = 19) using an ultra-high resolution mapping system. RAPW transverse conduction block was evaluated by the conduction pattern on propagation maps and double potentials separated by an isoelectric line.

Cardiac rehabilitation after catheter ablation of atrial fibrillation in patients with left ventricular dysfunction.

Few studies have examined the efficacy and safety of cardiac rehabilitation in patients with atrial fibrillation (AF) who underwent AF ablation. We explored the feasibility of additional cardiac rehabilitation after AF ablation in patients with a reduced left ventricular ejection fraction (LVEF). Fifty-four patients with heart failure (HF) and a reduced LVEF (HFrEF) (LVEF < 50%; 67.

Ultrahigh resolution electroanatomical mapping of the transverse conduction of the right atrial posterior wall in cases with and without typical atrial flutter.

Introduction: The right atrial posterior wall (RAPW) is known to form a conduction barrier during typical atrial flutter (AFL). We evaluated the transverse conduction properties of RAPW in patients with and without typical AFL using an ultrahigh resolution electroanatomical mapping system.

Methods And Results: This study included 41 patients who underwent catheter ablation of AF, typical or atypical AFL, in whom we performed RAPW mapping with an ultrahigh resolution mapping system during typical AFL and coronary sinus ostial pacing with three different pacing cycle lengths (PCLs) (1) PCL1: PCL within 40 ms of the AFL cycle length in patients with typical AFL or 250-300 ms for those without, (2) PCL2: 400 ms, (3) PCL3: PCL just faster than the sinus rate.

Extended Sedentary Time Increases the Risk of All-Cause Death and New Cardiovascular Events in Patients With Diabetic Kidney Disease.

Background: Sedentary behavior may be an independent risk factor for cardiovascular events. This study aimed to clarify the effects of extended sedentary time in patients with diabetic kidney disease (DKD) on the risk of all-cause death and new events.

Methods and results: A prospective cohort study was performed over 39 months.

A case of outflow tract premature ventricular contractions with very distant exit sites suspected to have a single origin.

Outflow tract premature ventricular contractions sometimes demonstrate multiple exit sites in the right and left outflow tracts with preferential pathways. Here we present a case of outflow tract premature ventricular contractions, which were eliminated by ablation from the right ventricular outflow tract accompanied by additional ablation from the very distant endocardial left ventricular outflow tract. The findings during the ablation indicated there was a single origin with multiple exit sites rather than multiple origins for each QRS morphology.

Phrenic nerve stimulation during right ventricular outflow tract pacing: A rare but possible complication.

Phrenic nerve stimulation (PNS) caused by a right ventricular (RV) lead is an uncommon complication of pacemaker implantations. We demonstrated a case of left PNS caused by an RV lead placed in the RV outflow tract (RVOT). The PNS was dependent on ventricular capture.