A5088403960- Cardiac electrophysiology and arrhythmias
- Cardiac Arrhythmias and Treatments
- Atrial Fibrillation Management and Outcomes
- Cardiac pacing and defibrillation studies
- Ion channel regulation and function
- Heart Rate Variability and Autonomic Control
- ECG Monitoring and Analysis
- Cardiovascular Syncope and Autonomic Disorders
- Cardiovascular Effects of Exercise
- Cardiovascular Function and Risk Factors
- Blood Pressure and Hypertension Studies
- Cardiac Imaging and Diagnostics
- Cardiac Fibrosis and Remodeling
- Antiplatelet Therapy and Cardiovascular Diseases
- Electrochemical Analysis and Applications
- Neuroscience and Neural Engineering
- Analytical Methods in Pharmaceuticals
- Neuroscience and Neuropharmacology Research
- Cardiovascular Disease and Adiposity
- Botulinum Toxin and Related Neurological Disorders
- Cardiac Valve Diseases and Treatments
- Coronary Artery Anomalies
- Venous Thromboembolism Diagnosis and Management
- Natural Products and Biological Research
- Protease and Inhibitor Mechanisms
Akebono Clinic
2017-2022
University of Toyama
2009-2019
Tohoku Medical and Pharmaceutical University
1994-2005
Chiba University
1997
Introduction: In Brugada syndrome, ventricular fibrillation (VF) occurs mainly during sleep, and ECG signs are intensified by parasympathomimetic drugs; therefore, vagal activity could be a precipitating factor of VF. The aim the present study was to elucidate relation between spontaneous augmentation ST elevation changes in autonomic nervous activities daily life patients with syndrome. Methods Results: Twenty‐three consecutive syndrome were studied. Group VF(+) consisted 7 symptomatic 3...
ST Segment Elevation by Class IC Drugs. We evaluated two patients without previous episodes of syncope who showed characteristic ECG changes similar to Brugada syndrome following administration drugs, flecainide and pilsicainide, but not IA drugs. Patient 1 had frequent paroxysmal atrial fibrillation resistant After treatment with flecainide, the a marked elevation in leads V 2 , 3 coved‐type configuration segment lead . A signal‐averaged late potentials that became more prominent after...
Allopurinol and Atrial Fibrillation . Aims: Oxidative stress could be a possible mechanism therapeutic target of atrial fibrillation (AF). Xanthine oxidase (XO) inhibition reduces oxidative stress, but the effects XO inhibitor on AF have not been evaluated. Hence, we assessed inhibitor, allopurinol, progression vulnerability in dogs associated with tachycardia‐induced cardiomyopathy. Methods Results: The were subjected to tachypacing (ATP, 400 bpm) without atrioventricular block for 4 weeks....
Effects of enalapril on a canine model atrial pacing-induced fibrillation (AF) with rapid ventricular responses were determined. Methods: Four weeks pacing was performed twenty-four beagles pretreated placebo (Group I, n = 14) or 1 mg/kg II, 10). Atrial effective refractory period (ERP), P-wave width, duration AF, and left ejection fraction (LVEF) evaluated every week. AF cycle length determined by spectral analyses waves. Quantitative analysis histology added. Results: After 4 pacing, width...
The electrocardiographic parameters relating occurrence of ventricular fibrillation (VF) episodes in patients with idiopathic VF (IVF) are still unknown. aim this study was to clarify efficacy pharmacological therapy IVF respect repolarization dynamics. group consisted 8 men (age 43.6 +/- 9.1 years) (Brugada type 5 patients, prominent J wave the inferior leads 3 patients) who had documented spontaneous VF, 7 whom implantable cardioverter defibrillators. relation between QT and RR interval...
VT originating from the right ventricular outflow tract (RVOT) is prone to occur when sympathetic nervous activity increased. β‐Blockade is, therefore, effective in suppressing this VT. The purpose of study was determine role sympathovagal balance assessed by heart rate variability (HRV) spontaneous initiation repetitive premature contractions (PVCs) and (five or more consecutive PVCs) arising RVOT seven patients without structural diseases. Frequency‐domain measures HRV were determined...
Introduction: This study tested whether bepridil, a multichannel blocker, would reverse electrical remodeling induced by persistent atrial tachycardia. Methods and Results: Fourteen dogs were subjected to rapid pacing at 400 bpm for 6 weeks after atrioventricular block was created control the ventricular rate. During period, seven given placebo (Control group), 3 weeks, followed of bepridil (10 mg/kg/day, Bepridil group). The effective refractory period (ERP) inducibility duration...
Background The aim of this study was to evaluate pharmacological cardioversion long-lasting persistent atrial fibrillation (AF) using bepridil in terms recovery mechanical function and maintenance sinus rhythm. Bepridil alone or combination with aprindine is effective for termination AF. Methods Results group comprised 38 consecutive patients (24 men, 58.8±9.3 years) successful conversion AF lasting >1 month either pharmacologically (Group I) electrically II). Fast Fourier transform analysis...
The aim of this study was to investigate the mechanism spontaneous termination atrial fibrillation (AF) by comparing it with drug-induced on basis changes in cycle length (FCL). Fast Fourier transform analysis carried out electrocardiogram (ECG) records 27 patients paroxysmal AF without organic heart disease. In 8 AF, spectral data from surface ECG lead V1 performed before and after class I antiarrhythmic drug infusion for 10 min. 19 used Holter recordings at min termination. FCL calculated...
Introduction: We evaluated the characteristics of QT‐RR and QaT (apex T wave)‐RR relationships in patients with idiopathic ventricular fibrillation (IVF) compared control subjects. hypothesized that IVF have unique repolarization dynamics related to a reduced fast Na current prominent transient outward current. Methods Results: The study group consisted 9 men (age 47 ± 10 years) (6 Brugada type 3 non‐Brugada type) who had experienced nocturnal episodes VF. 28 healthy age‐matched 44 12...
Introduction: Myocardial cooling can induce J point elevation (Osborn wave) as seen on ECG of the Brugada syndrome by activating transient outward current (I to ) and causing a spike‐and‐dome configuration monophasic action potential (MAP) in ventricular epicardium isolated canine wedge preparations. We determined effect regional epicardial right outflow tract (RVOT) surface vulnerability dog. Methods Results: In 12 dogs, device (20‐mm diameter) was attached RVOT epicardium, ECG, MAP,...
Idiopathic ventricular fibrillation (IVF) with early repolarization (ER) has recently been reported; however, ER is a common finding in healthy subjects and also found sporadically patients Wolff-Parkinson-White (WPW) syndrome. The present study was designed to evaluate the prevalence clinical significance of WPW syndrome.One hundred eleven syndrome were studied retrospectively. Early defined as QRS slurring or notching J-point elevation ≥ 1 mm. determined before after successful catheter...
The aim of this study was to use fast Fourier transform analysis clarify the characteristics human atrial fibrillation (AF) waves with respect duration AF and effect class I antiarrhythmic drugs. Twenty-two patients (10 paroxysmal AF, 12 persistent AF) without organic heart disease were studied by conventional electrophysiological methods. Electrograms recorded from right free wall during spectral performed for 35s (16 consecutive 4096-ms epochs 50% overlap) cycle length (FCL) calculated...
Background In patients with Brugada syndrome (BS), ventricular fibrillation (VF) occurs mainly during sleep; therefore, not only vagal activity but also bradycardia dependent changes in ECG may relate to the nighttime occurrence of VF. The present study aimed examine difference bradycardia-dependent symptomatic and asymptomatic BS patients. Methods Results Twenty-one were categorized into (n=9) (n=12) groups. During electrophysiologic study, evaluated at RR intervals 400, 600, 750, 1,000...
Anticoagulation control quality affects the incidence of thromboembolic events in atrial fibrillation (AF) patients. However, effects anticoagulation on prothrombotic state AF patients are unclear.Ninety-five who had been treated with warfarin were prospectively followed-up for 449 ± 92 days. We analyzed whether time therapeutic range (TTR) international normalized ratio (INR) prothrombin time, percentage INR values (%INR), and coefficient variation (CV-INR) related to D-dimer levels. The...
Background The aim of this study was to investigate whether drug-induced changes in fibrillation wave characteristics can predict pharmacological conversion long lasting persistent atrial (AF). Methods and Results group comprised 23 consecutive patients with AF ≥1 month. Patients first received bepridil (200 mg/day) for 2-4 weeks. When sinus rhythm not restored bepridil, oral aprindine (40 or 60 added bepridil. Fast Fourier transform analysis waves using lead V1 performed calculate the cycle...
Introduction : In patients with Brugada syndrome, the circadian variation of ST elevation could be modulated by autonomic nervous activity and RR interval. Recently, glucose‐induced insulin secretion was also reported to contribute fluctuation elevation. Therefore, we assessed effects taking meals on ST‐RR relationship in daily life syndrome. Methods Results: Twenty‐eight who had type I elevation, were categorized into 12 symptomatic 16 asymptomatic patients. Unipolar lead (V 2 ) Holter ECG...