bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical Efficacy of Bepridil for Class I Antiarrhythmic Drug‐Induced Atrial Flutter in Patients with Paroxysmal Atrial Fibrillation
Authors: Hayashi Hidemori , Sumiyoshi Masataka , Suwa Satoru , Sakurai Hidehiko , Kawano Yasunobu , Sekita Gaku , Tokano Takashi , Nakazato Yuji , Daida Hiroyuki 
Published: August 2012

Background: Class I antiarrhythmic drugs can promote the organization of atrial fibrillation (AF) and sometimes converts AF into atrial flutter (AFL) concomitant with difficulty of rate control. We studied the usefulness of Bepridil, which exhibits a class III‐like effect, for class I drug‐induced AFL in patients with paroxysmal AF.Methods: The study population consisted of 17 consecutive patients (15 men, mean age 65 ± 8 years) with AFL converted from paroxysmal AF following oral treatment of class IA or IC antiarrhythmic agents including pilsicainide (n = 8), cibenzoline (n = 5), flecainide (n = 2), aprindine (n = 1), and propafenone with cibenzoline (n = 1). After the occurrence of AFL, class I drug was replaced by bepridil with a dose of 100–200 mg per day in all patients.Results: After the treatment with bepridil, 15 (88%) out of the 17 patients restored sinus rhythm after 1 to 68 days (average of 21 days). In 12 (80%) of the 15 patients, sinus rhythm was maintained for an average of 23.6 months (range of 1 to 62 months) follow‐up period. Although torsade de pointes was not recognized, a marked QT prolongation (0.60 sec) was observed in one patient during the administration of bepridil at a daily dose of 200 mg. In this patient, QT interval was normalized (0.45 sec) after reduction of bepridil to 150 mg daily.Conclusion: Bepridil treatment may be safe and effective for class I drug‐induced AFL in patients with paroxysmal AF to restore and maintain sinus rhythm as an alternative therapy for catheter ablation. However, the QT interval must be carefully monitored during this medication.
Attenuating Effects of Anti‐Arrhythmic Agents on Changes in Fibrillation Cycle Length in Very Early Phase Paroxysmal Atrial Fibrillation —Spectral Analysis of Fibrillation Waves in Surface ECG—
Authors: Fukaya Hidehira , Niwano Shinichi , Sasaki Takeshi , Kiryu Michiro , Kurokawa Sayaka , Hatakeyama Yuko , Sato Daisuke , Yumoto Yoshihiro , Moriguchi Masahiko , Niwano Hiroe , Fujiki Akira , Izumi Tohru 
Published: August 2012

Background: Antiarrhythmic agents may affect electrical remodeling but little is known regarding clinical cases. We evaluated fibrillation cycle length (FCL) of atrial fibrillation (AF) by spectral analysis of fibrillation waves (FW) in surface ECG for patients on antiarrhythmic agents.Methods and Results: 18 patients (14 males; 58 ± 2 year‐old) with paroxysmal AF (pAF) lasting over 30 minutes recorded by Holter ECG were enrolled. FW was purified by subtraction of QRS‐T, and calculated by fast Fourier transformation analysis. FCL was defined as reciprocal of mean peak frequency. Temporal variability was expressed as FCL coefficient of variation (FCL‐CV). FCL and FCL‐CV were calculated at 0, 1, 5, 10, and 30 minutes after the onset of AF. We evaluated three groups: control group (6 patients with no medication), class I group (6 patients with pilsicainide or flecainide), and bepridil group (6 patients with bepridil). FCL showed quick‐shortening at first minute in control group (p < 0.001), and relatively slow‐shortening in class I group. In bepridil group, FCL was not significantly shortened within 30 minutes. FCL‐CV did not change, but was significantly larger in bepridil group.Conclusions: FCL of pAF showed significant shortening in control group, but FCL shortening was suppressed and FCL‐CV was larger in bepridil group. This result may indicate the specific effect of bepridil for electrical changes in early phase of pAF.
Clinical Background and Evaluation of Drug‐Induced Prolongation of QT Interval
Authors: Katoh Takao 
Published: August 2012

Prolongation of QT/QTc interval during medical treatment can occur not only with cardiovascular drugs but also with non‐cardiovascular drugs. It may result in ventricular tachyarrhythmia, a high‐risk condition which may trigger sudden cardiac death. Thus, to avoid drug‐induced long QT syndrome and serious complications careful attention should be paid in the clinical setting.Moreover, in the last several years objective evaluation by strictly applying electrocardiogram (ECG) data has been strongly recommended for the development of all new drugs in discussions held at the International Conference on Harmonization (ICH). This recommendation has already been adopted in the USA and the EU and is expected to be announced shortly in our country.Not only the drugs but a variety of patient background factors may influence ECG parameters, especially the QT/QTc interval. It is necessary to introduce an appropriate study protocol that can evaluate the risk for QT/QTc prolongation related to the drug. Additionally, an adequate system to record, measure, and evaluate ECG with high objectivity must be applied to all clinical trials.
Prevention of Torsade de Pointes during the Pharmacologic Treatment of Atrial Fibrillation
Authors: Mitamura Hideo 
Published: August 2012

AbstractPotassium channel blockers are sometimes effective in the rhythm management of persistent atrial fibrillation. However, on rare occasions, a life‐threatening episode of torsade de pointes develops during treatment with these agents. Among several precautions against this tragedy, preventing exaggerated QT prolongation is of paramount importance. One of the difficulties in monitoring the QT interval during atrial fibrillation is the fact that its length varies depending not only on the fluctuating preceding intervals, but on other factors such as neurohumoral activation. In fact, even at the same preceding RR interval, the QT interval may vary from day to night, between atrial fibrillation and sinus rhythm. Accordingly, the QTc interval may not be a reliable parameter for predicting proarrhythmic events. As the result, close monitoring of the QT interval itself, just like INR monitoring during warfarin treatment, is mandatory both before and during treatment with these agents.
A Case of Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia Using Transseptal Approach, Guided by Electro‐Anatomical Mapping System
Authors: Higuchi Takafumi , Takenaka Kotoe , Yamauchi Ryoko , Haruna Yoshizumi , Takenaka Hiroyuki , Ozaki Masaaki , Kitaguchi Shouji 
Published: August 2012

AbstractA 65 year‐old female was admitted to our hospital because of syncope. She has been previously diagnosed with dilated cardiomyopathy. Twelve‐lead electrocardiogram (ECG) presented narrow QRS tachycardia. Electrophysiological study and radiofrequency catheter ablation was performed. Under isoproterenol infusion, supraventricular tachycardia (SVT) was easily induced followed by critical AH interval. The mechanism of SVT was diagnosed with slow‐fast atrioventricular nodal reentrant tachycardia (AVNRT). We tried slow‐pathway ablation from venous approach targeted at the triangle of Koch using electrogram guide and anatomical approach. Slow‐pathway conduction was not eliminated, however, and SVT still could be easily induced. Therefore we delivered radiofrequency (RF) from the left atrial (LA) septum by transseptal approach using an electro‐anatomical mapping (EAM) system. After RF application at mid‐septum from the LA, the slow‐pathway conduction was modified and SVT could not be induced.
Efficacy and Safety of Bepridil for Patients with Persistent Atrial Fibrillation after Failed Electrical Cardioversion
Authors: Egami Yasuyuki , Nishino Masami , Taniike Masayuki , Makino Nobuhiko , Kato Hiroyasu , Shutta Ryu , Tanouchi Jun , Yamada Yoshio 
Published: August 2012

AbstractIntroduction: Bepridil is effective for atrial fibrillation (AF), but it can induce torsades de pointes. Thus we examined the efficacy and safety of bepridil when started at 100 mg/day for AF after failed electrical cardioversion (EC).Methods and Results: We studied 28 consecutive patients (58 ± 12 years old) with failed EC. After administration of bepridil, we examined the time to restore the sinus rhythm, the duration of the maintained sinus rhythm. Our patients were divided into the two groups and various clinical factors were compared, including medication and echocardiographic and electrocardiographic parameters: the SR group who maintained sinus rhythm during followup period and the AF group who still had AF. Sixteen patients (57%) could maintain sinus rhythm (SR group). Adverse arrhythmic events were not observed. There were no significant differences in any clinical factors between the two groups before and after bepridil.Conclusions: Bepridil was effective and safe for persistent AF with failed EC.
An Asymptomatic Case of Wolff‐Parkinson‐White Syndrome with Right‐sided Free‐wall Accessory Pathway and Left Ventricular Dysfunction
Authors: Mine Takanao , Kodani Takeshi , Hamaoka Mamoru , Masuyama Tohru 
Published: August 2012

AbstractA 16‐year‐old girl with a known history of asymptomatic Wolff‐Parkinson‐White syndrome exhibited signs of left ventricular (LV) septal akinesia and LV dysfunction during routine follow‐up. A 12‐lead surface ECG showed pre‐excitation, a predominantly negative delta wave in V1 and left axis deviation, which was consistent with the presence of a right free‐wall accessory pathway. Radiofrequency ablation of the anterolateral right atrium around the local shortest atrium‐to‐ventricle interval created the accessory pathway block. An echocardiogram taken one month after the procedure revealed that LV septal wall motion had normalized and that LV ejection fraction had improved from 50% before the ablation to 64% after the ablation. Most previous reports of asymptomatic patients of WPW with LV septal dyskinesia and dysfunction have described right septal or posteroseptal accessory pathways. This patient reported here represents a rare case with right free‐wall accessory pathway and LV dysfunction without tachycardia.
Postural Orthostatic Tachycardia Syndrome (POTS)
Authors: Mizumaki Koichi 
Published: August 2012

Postural orthostatic tachycardia syndrome (POTS) is defined as the development of orthostatic symptoms associated with a rapid (within 10 minutes) increase in heart rate by more than 30 beats per minute or to a heart rate that exceeds 120 beats per minute without orthostatic hypotension. The symptoms of orthostatic intolerance are due to brain hypoper fusion and sympathetic overaction. Patients are usually female and aged 15 to 50 years. POTS represents a category of disease rather than a single distinct illness. Patients with POTS can experience difficulty with daily routines including housework, shopping, eating, and attending work or school. Reports of patients with “POTS‐like symptoms” have been made for over 100 years.The pathophysiologic mechanisms of POTS include peripheral denervation, β‐receptor supersensitivity, hypovolemia and impaired cerebral auto regulation. Prolonged deconditioning may also interact with these mechanisms to exacerbate symptoms. Although 3 types of POTS (low‐flow, normal‐flow, and high‐flow POTS) have been distinguished based on differences in peripheral blood flow and peripheral arterial resistance, thoracic hypovolemia is the common final pathophysiologic mechanism.Therapies are directed at relieving the central hypovolemia or at compensating for the circulatory dysfunctions. Treatments include use of water, saline infusion, α‐agonists, β‐antagonists, and other agents that may correct the central hypovolemia. These have resulted in varying degrees of success, and they are often used in combination.
Impact of Antiarrhythmic Drugs on Complex Fractionated Atrial Electrograms
Authors: Kumagai Koichiro , Toyama Hideko 
Published: August 2012

Background: Ablation of complex fractionated atrial electrograms (CFAE) is now performed in patients with persistent atrial fibrillation (AF). However, extensive ablation is often necessary to eliminate all CFAE or to terminate AF. The purpose of this study was to evaluate the effects of antiarrhythmic drugs (AAD) on CFAE.Methods and Results: Sixty patients, including 38 with longstanding persistent AF and 22 with persistent AF, underwent box isolation. After box isolation, CFAE maps were created before and after infusion of a pure Na+ blocker, pilsicainide (1 mg/kg), in 30 patients or a pure IKr blocker, nifekalant (0.3 mg/kg), in 30 patients. Nifekalant had a greater effect on AF termination than pilsicainide (33.3% versus 6.7%, P = 0.01). Both AADs similarly reduced CFAE. Ablation of CFAE localized by nifekalant and pilsicainide terminated AF in 26.7% and 20% of the patients, respectively. After a single ablation procedure, patients in whom AF was terminated by CFAE ablation had a lower recurrence rate than those in whom AF was not terminated despite CFAE ablation (19.2% vers us 35.3%, P = 0.04).Conclusions: Both pilsicainide and nifekalant reduce CFAE, and nifekalant has a greater effect on AF termination than pilsicainide. Ablation of only CFAE localized with AAD may be sufficient for clinical efficacy.
Hyperbolicity in the volume-preserving scenario
Authors: ARBIETO ALEXANDER , CATALAN THIAGO 
Published: August 2012

AbstractExtending a result of Mañé, Hayashi proved that every diffeomorphism$f$which has a$C^1$-neighborhood$\mathcal {U}$where all periodic points of any$g\in \mathcal {U}$are hyperbolic is an Axiom A diffeomorphism. Here we prove the analogous result in the volume-preserving scenario.
Transition to turbulence at the bottom of a solitary wave
Authors: Blondeaux Paolo , Pralits Jan , Vittori Giovanna 
Published: August 2012

AbstractA linear stability analysis of the laminar flow in the boundary layer at the bottom of a solitary wave is made to determine the conditions leading to transition and the appearance of turbulence. The Reynolds number of the phenomenon is assumed to be large and a ‘momentary’ criterion of instability is used. The results show that the laminar regime becomes unstable during the decelerating phase, when the height of the solitary wave exceeds a threshold value which depends on the ratio between the boundary layer thickness and the local water depth. A comparison of the theoretical results with the experimental measurements of Sumer et al. (J. Fluid Mech., vol. 646, 2010, pp. 207–231) supports the analysis.
Linear global instability of non-orthogonal incompressible swept attachment-line boundary-layer flow
Authors: Pérez José Miguel , Rodríguez Daniel , Theofilis Vassilis 
Published: August 2012

AbstractFlow instability in the non-orthogonal swept attachment-line boundary layer is addressed in a linear analysis framework via solution of the pertinent global (BiGlobal) partial differential equation (PDE)-based eigenvalue problem. Subsequently, a simple extension of the extended Görtler–Hämmerlin ordinary differential equation (ODE)-based polynomial model proposed by Theofilis et al. (2003) for orthogonal flow, which includes previous models as special cases and recovers global instability analysis results, is presented for non-orthogonal flow. Direct numerical simulations have been used to verify the analysis results and unravel the limits of validity of the basic flow model analysed. The effect of the angle of attack, $\mathit{AoA}$, on the critical conditions of the non-orthogonal problem has been documented; an increase of the angle of attack, from $\mathit{AoA}= 0$ (orthogonal flow) up to values close to $\lrm{\pi} / 2$ which make the assumptions under which the basic flow is derived questionable, is found to systematically destabilize the flow. The critical conditions of non-orthogonal flows at $0\leq \mathit{AoA}\leq \lrm{\pi} / 2$ are shown to be recoverable from those of orthogonal flow, via a simple algebraic transformation involving $\mathit{AoA}$.
Compound capillary rise
Authors: Weislogel Mark M. 
Published: August 2012

AbstractIrregular conduits, complex surfaces, and porous media often manifest more than one geometric wetting condition for spontaneous capillary flows. As a result, different regions of the flow exhibit different rates of flow, all the while sharing common dynamical capillary pressure boundary conditions. The classic problem of sudden capillary rise in tubes with interior corners is revisited from this perspective and solved numerically in the self-similar ${\ensuremath{\sim} }{t}^{1/ 2} $ visco-capillary limit à la Lucas–Washburn. Useful closed-form analytical solutions are obtained in asymptotic limits appropriate for many practical flows in conduits containing one or more interior corner. The critically wetted corners imbibe fluid away from the bulk capillary rise, shortening the viscous column length and slightly increasing the overall flow rate. The extent of the corner flow is small for many closed conduits, but becomes significant for flows along open channels and the method is extended to approximate hemiwicking flows across triangular grooved surfaces. It is shown that an accurate application of the method depends on an accurate a priori assessment of the competing viscous cross-section length scales, and the expedient Laplacian scaling method is applied herein toward this effect.
A pulse-based diet is effective for reducing total and LDL-cholesterol in older adults
Authors: Abeysekara Saman , Chilibeck Philip D. , Vatanparast Hassanali , Zello Gordon A. 
Published: August 2012

Our purpose was to determine the effects of a pulse-based diet in individuals 50 years or older for reducing CVD risk factors. A total of 108 participants were randomised to receive pulse-based foods (two servings daily of beans, chickpeas, peas or lentils; about 150 g/d dry weight) or their regular diet for 2 months, followed by a washout of 1 month and a cross-over to the other diet for 2 months. Anthropometric measures, body composition and biochemical markers (i.e. serum LDL-cholesterol (LDL-C), as the primary outcome, and other lipids, glucose, insulin and C-reactive protein) were assessed before and after each diet phase. A total of eighty-seven participants (thirty males and fifty-seven females; 59·7 (sd6·3) years, body mass 76 (sd16) kg) completed the study. Compared with the regular diet, the pulse-based diet decreased total cholesterol by 8·3 % (pulse, 4·57 (sd0·93) to 4·11 (sd0·91) mmol/l; regular, 4·47 (sd0·94) to 4·39 (sd0·97) mmol/l;P < 0·001) and LDL-C by 7·9 % (pulse, 2·93 (sd0·84) to 2·55 (sd0·75) mmol/l; regular, 2·96 (sd0·86) to 2·81 (sd0·83) mmol/l;P = 0·01). In a sub-analysis of individuals with high lipid levels at baseline (twenty individuals with high cholesterol), the pulse-based diet reduced cholesterol by 6 % compared with the regular diet (pulse, 5·62 (sd0·78) to 5·26 (sd0·68) mmol/l; regular, 5·60 (sd0·91) to 5·57 (sd0·85) mmol/l;P = 0·05). A pulse-based diet is effective for reducing total cholesterol and LDL-C in older adults and therefore reduces the risk of CVD.
In vitro investigations of the potential health benefits of Australian-grown faba beans (Vicia faba L.): chemopreventative capacity and inhibitory effects on the angiotensin-converting enzyme, α-glucosidase and lipase
Authors: Siah Siem D. , Konczak Izabela , Agboola Samson , Wood Jennifer A. , Blanchard Christopher L. 
Published: August 2012

The functional properties, including antioxidant and chemopreventative capacities as well as the inhibitory effects on angiotensin-converting enzyme (ACE), α-glucosidase and pancreatic lipase, of three Australian-grown faba bean genotypes (Nura, Rossa and TF(Ic*As)*483/13) were investigated using an array of in vitro assays. Chromatograms of on-line post column derivatisation assay coupled with HPLC revealed the existence of active phenolics (hump) in the coloured genotypes, which was lacking in the white-coloured breeding line, TF(Ic*As)*483/13. Roasting reduced the phenolic content, and diminished antioxidant activity by 10–40 % as measured by the reagent-based assays (diphenylpicrylhydrazyl, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) and oxygen radical absorbance capacity) in all genotypes. Cell culture-based antioxidant activity assay (cellular antioxidant activity) showed an increase of activity in the coloured genotypes after roasting. Faba bean extracts demonstrated cellular protection ability against H2O2-induced DNA damage (assessed using RAW264.7 cells), and inhibited the proliferation of all human cancer cell lines (BL13, AGS, Hep G2 and HT-29) evaluated. However, the effect of faba bean extracts on the non-transformed human cells (CCD-18Co) was negligible. Flow cytometric analyses showed that faba bean extracts successfully induced apoptosis of HL-60 (acute promyelocytic leukaemia) cells. The faba bean extracts also exhibited ACE, α-glucosidase and pancreatic lipase inhibitory activities. Overall, extracts from Nura (buff-coloured) and Rossa (red-coloured) were comparable, while TF(Ic*As)*483/13 (white-coloured) contained the lowest phenolic content and exhibited the least antioxidant and enzyme inhibition activities. These results are important to promote the utilisation of faba beans in human diets for various health benefits.
Metabolism and performance during extended high-intensity intermittent exercise after consumption of low- and high-glycaemic index pre-exercise meals
Authors: Bennett Christine B. , Chilibeck Philip D. , Barss Trevor , Vatanparast Hassanali , Vandenberg Albert , Zello Gordon A. 
Published: August 2012

The metabolic and performance benefits of prior consumption of low-glycaemic index (GI) meals v. high-GI meals were determined in extended high-intensity intermittent exercise. Participants (ten males and four females, aged 25·8 (sd 7·3) years) completed two testing days (each consisting of back-to-back 90-min intermittent high-intensity treadmill running protocols separated by 3 h) spaced by at least 7 d. Using a randomised counterbalanced cross-over design, low-GI, lentil-based meals (GI about 42) or high-GI, potato-based meals (GI about 78) matched for energy value were consumed 2 h before, and within 1 h after, the first exercise session. Performance was measured by the distance covered during five 1-min sprints (separated by 2·5 min walking) at the end of each exercise session. Peak postprandial blood glucose was higher by 30·8 % in the high-GI trial compared with the low-GI trial, as was insulin (P = 0·039 and P = 0·003, respectively). Carbohydrate oxidation was lower by 5·5 % during the low-GI trials compared with the high-GI trials at the start of the first exercise session (P < 0·05). Blood lactate was significantly higher (6·1 v. 2·6 mmol/l; P = 0·019) and blood glucose significantly lower (4·8 v. 5·4 mmol/l; P = 0·039) at the end of the second exercise session during the high-GI trial compared with the low-GI trial. Sprint distance was not significantly different between conditions. A low-GI meal improved the metabolic profile before and during extended high-intensity intermittent exercise, but did not affect performance. Improvements in metabolic responses when consuming low-GI meals before exercise may be beneficial to the long-term health of athletes.