Publications by authors named "Shu Yamashita"
Article Synopsis
- Typical atrial flutter (AFL) is characterized by a macroreentrant tachycardia, specifically with electrocardiographic features like a negative sawtooth wave in inferior leads and a positive F wave in lead V1.
- This study analyzed 10 patients undergoing radiofrequency catheter ablation for AFL, using electroanatomical mapping to investigate the origins of the F wave changes during entrainment from the right atrial appendage (RAA).
- Results showed that the positive F wave in lead V1 fluctuated with RAA entrainment, revealing an area of antidromic capture that collided with the orthodromic wave, confirming its role as the source of the F wave changes during typical AFL.
Background: Since the local impedance (LI) of the ablation catheter reflects tissue characteristics, the efficacy of higher power (HP) compared to lower power (LP) in LI-guided ablation may differ from other index-guided ablations.
Objective: This study aimed to assess the efficacy of HP ablation in LI-guided ablation of atrial fibrillation (AF).
Methods: A prospective observational study was conducted, enrolling patients undergoing de novo ablation for AF.
Backgrounds: Catheter ablation for non-paroxysmal atrial fibrillation (non-PAF) remains challenging and more effective strategy has been required to reduce postoperative arrhythmia recurrences. This study aims to investigate the efficacy and safety of a novel extensive ablation strategy for non-PAF, that is based on a combination of cryoballoon (CBA), radiofrequency (RFA), and Marshall-vein ethanol ablations (EA-VOM).
Methods: The study was a single-center, retrospective observational study.
Article Synopsis
- The study investigates whether the angle of tines on the Micra leadless pacemaker affects their engagement with the heart muscle during implantation.
- Researchers analyzed data from 93 patients and found that tines with angles less than 10 degrees were always engaged, while higher angles made engagement unpredictable.
- The findings suggest that measuring the angle of the tines before testing can help predict whether they are securely anchored to the myocardium.
We herein report a case of pulmonary veno-occlusive disease (PVOD) induced by allo-hematopoietic stem cell transplantation (HSCT) in a 48-year-old man who was diagnosed with acute myeloid leukemia. Five months after transplantation, he developed dyspnea and was diagnosed with pulmonary hypertension based on right heart catheterization. Although he received treatment with pulmonary vasodilators, diuretics, and corticosteroids, his pulmonary artery pressure did not decrease, and his pulmonary edema worsened.
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- Leadless pacemaker implantation has a lower risk of cardiac perforation when placed in the septum, but the effects on success rates and complications based on implantation site are not fully understood.
- A study analyzed 67 patients who had post-procedural CT scans to compare outcomes between those with septal and non-septal placements, revealing that the non-septal group had better pacemaker performance but faced higher complication rates.
- The findings suggest while septal placements may reduce cardiac injury risks, they could lead to poorer pacemaker performance compared to non-septal placements.
Background: Subselection inner catheters (Inner-Cath) are used adjunctively with outer guiding catheters (Outer-Cath) during cardiac resynchronization therapy (CRT) device implantation. This study aims to investigate the feasibility and efficacy of left ventricular lead placement (LV-LP) guided by Inner-Cath alone.
Methods: A total of 74 patients undergoing de novo CRT implantation were investigated.
Endovascular treatment (EVT) for lower-limb peripheral artery disease patients reduces blood pressure (BP) and improves prognosis. This study retrospectively examined hemodynamics during EVT to clarify the mechanism. Systemic vascular resistance (SVR) was measured using a noninvasive continuous cardiac output monitoring system during EVT.
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- This study investigates how changes in brain natriuretic peptide (BNP) levels before and after catheter ablation for atrial fibrillation (AF) affect patient outcomes, specifically in those also dealing with heart failure (HF).
- In the analysis of 162 patients, those with AF at baseline showed a significant decrease in BNP levels post-ablation, while those in sinus rhythm saw an increase, with poor BNP reduction being linked to worse long-term outcomes like HF hospitalization and increased mortality.
- The findings suggest that monitoring BNP levels can help identify high-risk patients after sinus rhythm is restored, even though the recurrence rates of AF were similar among different BNP response groups.
Utility of a ripple map for the interpretation of atrial propagation during atrial tachycardia.
J Interv Card Electrophysiol
December 2019
Purpose: Ripple map (RM) is a novel method for displaying activation pattern on the surface of a cardiac chamber. The aim of this study was to determine the utility of the RM in interpreting the atrial propagation in atrial tachycardia (AT) in comparison with a conventional local activation (LAT) map.
Methods: Three-dimensional electroanatomical mapping and ablation of AT were performed using multielectrode catheters and the CARTO3 ConfiDENSE Module (Biosense Webster).
Background: Little is known about the long-term outcome and recurrent form recurrence after catheter ablation of atrial fibrillation (AF) in patients with long-standing persistent AF.
Methods: Two hundred thirty-six patients with persistent AF (193 men; age, 61.5±10.
We present a case of a 37-year-old female who complained of frequent palpitations caused by an atrial tachycardia and atrial premature contractions. Angiography revealed that the coronary sinus was occluded at the ostium and connected to a persistent left superior vena cava. An electrophysiological study and three-dimensional mapping revealed that the origin of the atrial tachycardia and atrial premature contractions was at the coronary sinus ostium in the right atrium.
View Article and Find Full Text PDFTolvaptan, a vasopressin type 2 receptor antagonist, does not affect kidney circulation or cause worsening of renal function (WRF) in patients with acute decompensated heart failure (ADHF). Bioelectrical impedance analysis (BIA) can be used to evaluate intravascular volume by calculating the ratio of extracellular water (ECW) to intracellular water (ICW). There have been no reports examining the mechanisms of tolvaptan-induced diuresis using BIA.
View Article and Find Full Text PDFBackground: Efficacy of catheter ablation (CA) of asymptomatic persistent atrial fibrillation (AF) remains unclear. We assessed the quality of life (QOL), exercise performance (EP), and plasma B-type natriuretic peptide (BNP) levels following CA in patients with asymptomatic AF.Methods and Results:We enrolled 34 patients with asymptomatic persistent AF.
View Article and Find Full Text PDFBackground: Atrial fibrillation (AF) often coexists with Wolff-Parkinson-White (WPW) syndrome. We compared the efficacy of Kent bundle ablation alone and additional AF ablation on accompanying AF, and examined which patients would still have a risk of AF after successful Kent bundle ablation.
Methods: This retrospective multicenter study included 96 patients (56±15 years, 72 male) with WPW syndrome and AF undergoing Kent bundle ablation.