bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphological Properties of Atrial Fibrillation Waves in Patients with Left Ventricular Dysfunction—Spectral Analysis of Atrial Fibrillation Waves in Dilated Cardiomyopathy—
Authors: Sasaki Takeshi , Niwano Shinichi , Fukaya Hidehira , Sasaki Sae , Imaki Ryuta , Yuge Masaru , Hirasawa Shoji , Satoh Daisuke , Moriguchi Masahiko , Fujiki Akira , Izumi Tohru 
Published: August 2012

AbstractIntroduction: Although the atrial fibrillation cycle length (FCL) is considered to shorten in persistent atrial fibrillation (AF) as a result of electrical remodeling, whether a long‐term change remains in FCL in patients with left ventricular (LV) dysfunction is uncertain. Morphological properties of AF waves were analyzed in patients with dilated cardiomyopathy (DCM). Methods and Results: The study population consisted of 43 patients with persistent AF, and they were divided into a DCM group (n = 14) and a control group (n = 29). Fibrillation waves from surface ECG lead V1 were purified by subtracting the QRS‐T complex template. Power spectral analysis was performed by Fast Fourier Transformation, and the mean FCL was determined by the peak power frequency in 20 epochs at each recording. The LV ejection fraction was lower in the DCM group (50 ± 18%) than the control (63 ± 8%, p = 0.001). The mean FCL was shorter in the DCM group (132 ± 14 ms) than the control (151 ± 23 ms, p = 0.007) and there was a significant correlation between the FCL and LV dimensions (p = 0.03). Conclusion: In patients with persistent AF and LV dysfunction, FCL was shorter in comparison with the control, and seemed to be influenced by LV dimensions.
Surgical Treatment of Chronic Atrial Fibrillation—Unipolar Radiofrequency Ablation versus Cryoablation, and Left Atrial versus Bi‐atrial Maze Procedures
Authors: Yoshikawa Masaharu , Usui Akihiko , Ueda Yuichi 
Published: August 2012

AbstractThis study evaluated the efficacy of the left atrial Maze procedure (Lt‐maze) and unipolar radiofrequency (RF) ablation as an additional procedure for the surgical treatment of atrial fibrillation (AF) in patient with other cardiac disease.Methods and Results: The Maze procedure was performed in 100 consecutive patients with AF: Lt‐maze, 71 patients; bi‐atrial Maze (Bi‐maze), 29 patients. Cryoablation and RF ablation were used in 82 and 18 patients, respectively. There were no in‐hospital or early deaths. Fourteen patients (14%) experienced postoperative complications. Seventy‐five patients (75%) were in sinus rhythm (SR) at discharge, 4 patients were in junctional rhythm, and 21 patients had AF. Two patients (2%) required permanent pacemaker implantation. The AF‐free rate at discharge was 79%, and the AF‐free rate at hospital discharge did not differ significantly between cryoablation and unipolar RF ablation (78% and 82%, respectively). There were no significant differences between these two groups in operative results, in terms of the aortic cross‐clamp time, cardiopulmonary bypass time, and AF‐free rate, with the AFfree rate not differing significantly in those who received single valve surgery (73% and 75% in the cryoablation and unipolar RF ablation groups, respectively). The equipment cost of the two procedures differed greatly: 14,000 yen/patient for cryoablation and 250,000 yen/patient for RF ablation. The AF‐free rate did not differ significantly between Lt‐maze (76%) and Bi‐maze (86%), including in those who received single valve surgery (72% and 79%, respectively). The significant predictors of AF recurrence in a univariate analysis were left atrial diameter (p = 0.03), duration of AF (p < 0.01), fibrillation amplitude on ECG (p = 0.02), and cardiothoracic ratio (p < 0.01), with the duration of preoperative AF being the only significant predictor of AF in a multivariate analysis.Conclusion: In this series, unipolar RF ablation for the Maze procedure was as effective as cryoablation at eliminating AF, and Lt‐maze and Bi‐maze were equipotent at restoring SR at discharge.
Late Post‐operative Perforation of the Right Ventricle by a Tined Pacing Lead—Report of a Case—
Authors: Noma Mio , Enomoto Yoshiharu , Matsushita Shounosuke , Hiramatsu Yuji , Shigeta Osamu , Toyama Masahiro , Sakakibara Yuzuru 
Published: August 2012

AbstractMyocardial perforation by a pacing lead occurred 12 days after implantation. The lead was propelled into the myocardium of the anterior wall of ventricles without passing through the left ventricular cavity, and finally protruded into the pericardial cavity. Computed tomography of the chest was helpful for confirming the perforation by the pacing lead.
Catheter Ablation for Three Focal Atrial Tachycardias in a Patient with Prior Fontan Surgery for Tricuspid Atresia
Authors: Kofune Masayoshi , Watanabe Ichiro , Ashino Sonoko , Okumura Yasuo , Hashimoto Kenichi , Okubo Kimie , Tokai Koichiro , Shindo Atsushi , Sugimura Hidezou , Nakai Toshiko , Saito Satoshi 
Published: August 2012

AbstractA 28‐year‐old woman who had undergone Fontan surgery for tricuspid atresia at 6 years of age was admitted to Nihon University Hospital due to syncope. Supraventricular tachycardia at 141 beats/min was induced with isoproterenol infusion during a tilt table test. The patient showed atresia of the right atrial orifice of the coronary sinus with persistent drainage into the left superior vena cava. Electrophysiological study was performed. Atrial tachycardia (AT) was induced by rapid atrial pacing. The AT originated in the lower lateral right atrium and electroanatomical mapping showed a focal origin. After successful ablation of the AT, two additional ATs were induced. These ATs were also shown to be of focal origin and were successfully ablated without recurrence during follow‐up.
Long‐term Efficacy of Combination Therapy with Anti‐arrhythmic Agents and Pravastatin in Patients with Paroxysmal Atrial Fibrillation
Authors: Komatsu Takashi , Tachibana Hideaki , Sato Yoshihiro , Ozawa Mahito , Ohshima Kyoko , Nakamura Motoyuki , Horiuchi Daisuke , Kobayashi Takao , Okumura Ken 
Published: August 2012

Objective: To investigate the long‐term effects of combination therapy with antiarrhythmic agents and pravastatin (10 mg/day) in maintaining sinus rhythm in patients with paroxysmal atrial fibrillation (AF) and hyperlipidemia.Method and Results: In all, 318 patients (mean age: 69 ± 12 years) with paroxysmal AF were divided into 2 groups, one receiving pravastatin for hyperlipidemia (pravastatin (+) group, N = 41) and the other not (pravastatin (−) group, N = 277). At 60 months, the survival rate for patients free from conversion to permanent AF was significantly greater in the pravastatin (+) group than in the pravastatin (−) group. The percentage of patients who eventually developed permanent AF despite anti‐arrhythmic therapy was significantly lower in the pravastatin (+) group than in the pravastatin (−) group (9.8% vs. 25.3%). Left atrial dimensions were significantly increased in the pravastatin (−) group during the follow‐up period (from 34.8 ± 6.6 mm to 37.6 ± 7.0 mm: p < 0.01). In contrast, in the pravastatin (+) group, left atrial dimensions remained unchanged between baseline and after treatment (34.4 ± 7.3 mm vs 35.5 ± 6.6 mm).Conclusion: In patients with paroxysmal AF and hyperlipidemia, addition of pravastatin to anti‐arrhythmic agents seems to enhance the efficacy of these agents in maintaining sinus rhythm and preventing the development of structural remodeling in the myocardium.
Quality of Life and Psychological Factors in Patients with Implantable Cardioverter Defibrillator
Authors: Suyama‐Chishaki Akiko , Miyazono Mami , Tsuchihashi‐Makaya Miyuki , Chishaki Hiroaki , Inoue Syujiro , Mukai Yasushi , Takemoto Masao , Kaji Ryoichi , Koike George , Maruyama Toru , Sunagawa Kenji , Arimura Tatsuyuki , Kubo Chiharu 
Published: August 2012

INTRODUCTION: As indication for implantable cardioverter defibrillators (ICDs) has expanded, prophylactic implantations have increased. It has been well understood that some ICD recipients have psychological problems. Some of those problems are recognized as maladjustment syndromes.METHODS: We studied 35 ICD recipients regularly followed at outpatient department of Kyushu University Hospital in order to clarify the psychological distress and the quality of their daily lives (QOL). By using questionnaire instruments (SF‐8, Beck Depression Inventory, Impact of Event Scale Revised, and State‐Trait Anxiety Inventory), we studied their psychological status.RESULTS: Depression, anxiety, and post‐stress syndromes existed in 45.5% of the ICD recipients and their QOL was compromised. Female ICD recipients reacted to the stress related to ICD implantation differently from male recipients. Elder ICD recipients had a different way of adjustment from the younger recipients. Various ICD related psychological problems were noted in terms of magnitude and diversity.CONCLUSION: To support ICD recipients both physically and mentally, not only the cardiologists but also specialists from other fields such as psychologists and nurse specialists are needed. Ancillary care must be provided through the support team. Cardiologists who determine whether ICD implantation is required must keep in mind potential psychological sequelae.
Efficacy and Safety of Strict Voltage‐based Substrate Mapping and Radiofrequency Catheter Ablation in Electrical Storms—Review of Substrate‐mapping Guided Ablation in Frequent Appropriate Shocks
Authors: Arimoto Takanori , Tada Hiroshi , Sekiguchi Yukio , Koyama Takashi , Igarashi Miyako , Yamasaki Hiro , Machino Takeshi , Kuroki Kenji , Kuga Keisuke , Aonuma Kazutaka 
Published: August 2012

Background: We investigated the efficacy and safety of strict voltage‐based substrate mapping and radiofrequency catheter ablation (SV‐substrate‐map ablation) in patients with electrical storm.Methods and Results: SV‐substrate‐map ablation was performed in 15 patients suffering from multiple appropriate shocks (6.0 ± 3.8/day) from implantable cardioverter defibrillators (ICDs). Strict voltage criteria were defined as: non‐arrhythmogenic areas, >0.6mV; low voltage areas, >0.1 to ≤0.6 mV; and scar, ≤0.1 mV. Using an electroanatomic mapping system, catheter ablation was performed at every possible arrhythmogenic region inside the low voltage areas. Further, we presented a review of the literature and investigated the published data on substrate‐mapping guided ablation for electrical storm. After repeat endocardial ablation procedures in 4 patients and an epicardial approach in one, the targeted ventricular tachycardias (VTs) were successfully ablated, and the electrical storms were completely controlled in all. During a mean follow‐up period of 801 ± 409 days, only one VT followed by an appropriate ICD shock was observed. No potential complications occurred during the procedure or follow‐up. Our results were comparable or better than that of previous substrate‐mapping guided ablation studies.Conclusion: SV‐substrate‐mapping ablation may be effective and safe for resolving serious clinical situations and prolonging the longevity of ICD devices in patients with electrical storms.
The Utility of Transtelephonic Electrocardiograms for Detecting Arrhythmia Recurrences after Radiofrequency Catheter Ablation for Atrial Fibrillation
Authors: Senga Michiharu , Fujii Eitaro , Sugiura Shinya , Yamazato Shoichiro , Nakamura Mashio , Ito Masaaki 
Published: August 2012

Background: Extensive encircling pulmonary vein isolation (EEPVI) is effective for atrial fibrillation (AF). However, the definition of success following ablation is commonly based on the lack of symptoms. The purpose of this study was to determine the incidence of recurrences of AF by daily transtelephonic electrocardiogram (T‐ECG), as compared with Holter ECG, after ablation of AF.Methods: Twenty‐two patients with AF underwent EEPVI. Holter ECG tests were performed at one, three, and six months, in addition to a daily T‐ECG for the first 180 days after ablation.Results: A total of 6012 T‐ECGs were obtained. Of these, 18.9% (1136) showed AF. Patients with AF were asymptomatic for 41.4% (470) of the episodes. Additionally, in 64% (14 of 22) of the patients, AF recurrences were recorded by T‐ECG, whereas Holter ECG tests did not detect AF recurrences in 50% of the patients (7 of 14).Conclusions: T‐ECG is better than Holter ECG in detecting AF relapses. The absence of symptoms should not be interpreted as absence of AF.
Antithrombotic Therapy According to the Guidelines Issued by the Japanese Circulation Society in Patients with Nonvalvular Paroxysmal Atrial Fibrillation without Thromboembolic Risk Factors
Authors: Ozawa Mahito , Komatsu Takashi , Tachibana Hideaki , Sato Yoshihiro , Orii Makoto , Kunugita Fusanori , Nakamura Motoyuki 
Published: August 2012

Aim and method: There have been few reports about the risk of ischemic stroke in elderly patients with non‐valvular paroxysmal atrial fibrillation (NVPAF). The aim of this study was to evaluate the validity of the guidelines issued by the Japanese Circulation Society to prevent ischemic stroke for NVPAF in patients without a high risk of ischemic stroke. The risk evaluation was made based on the CHADS2 Score. However, we excluded age in this study, but included coronary disease. This study investigated a total of 150 patients with paroxysmal atrial fibrillation (AF) who did not have a high risk of stroke (117 men and 33 women, mean age 68 ± 12 years). The patients were divided into three groups according to age: the patients who were less than 60 years old (Group I, N = 58, Antithrombic therapy (+) = 18), those who were between 60 and 75 years old (Group II, N = 68, Antithrombic therapy (+) = 36) and those who were more than 75 years old (Group III, N = 24, Antithrombic therapy (+) = 7). The annual rates of thromboembolism among three groups were retrospectively analyzed. The mean follow‐up periods were 56 ± 37 months.Results: (1) The annual rate of thromboembolism in Group III (4.0%) was significantly higher than in Group I (1.4%) and Group II (1.8%) (P < 0:05). (2) The annual rates of thromboembolism in patients without antithrombotic therapy were 2.1% in Group I, 1.3% in Group II and 3.9% in Group III. The annual rate was significantly lower in Group II than in Group III (P < 0:05). (3) The annual rates of thromboembolism with aspirin treatment (80‐ 100 mg/day) were 0% in Group I, 3.0% in Group II and 8.4% in Group III. There was a significant difference in the annual rate among the three groups (P < 0:05). (4) The annual rate of thromboembolism in patients with warfarin treatment was 0% in Group I, 1.5% in Group II and 0% in Group III (P = NS among 3 groups). Conclusion: Antithrombic therapy is required in elderly patients with NVPAF to prevent ischemic stroke. Antithrombic therapy with Warfarin, but not aspirin, reduces ischemic stroke in patients with NVPAF regardless of their age.
Effects of Bepridil on Atrial Electrical Remodeling in Short‐Term Rapid Pacing
Authors: Tsuchiya Hiroto , Nakazato Yuji , Hayashi Hidemori , Suzuki Takeshi , Sekita Gaku , Daida Hiroyuki 
Published: August 2012

Introduction: Bepridil is a multi‐ion channel blocker similar to amiodarone. Recent clinical studies have indicated that bepridil shows a favorable efficacy for the treatment of atrial fibrillation (AF). The purpose of this study is to evaluate the effectiveness of bepridil for electrical remodeling induced by rapid atrial stimulation particularly in the acute‐phase.Methods and Results: We studied 18 pigs subjected to right atrial appendage rapid pacing at 500 beats/min for 3 hours that were randomly assigned to the absence or presence of bepridil administration for 14 days. They were divided into 2 groups, an atrial pacing only group (PG; n = 10) and an atrial pacing plus bepridil group (PBG; n = 8). We measured the effective refractory period (ERP) at the right atrial free wall (RAFW), the right atrial appendage (RAA) and the left atrial free wall (LAFW), as well as the monophasic action potential duration at 90% (MAPD90) in RAA during the rapid pacing phase and recovery phase.In the PG, the ERP decreased gradually at all atrial sites during the 3 hour phase of rapid pacing. In contrast, the shortening of the ERP was suppressed significantly at the RAFW and LAFW in the PBG. The MAPD90 was also shortened by rapid atrial pacing in the PG. This shortening was suppressed significantly in the PBG.We evaluated the effect of bepridil on the inducibility of AF during all time spans. The mean number of AF occurrences in the PBG was significantly fewer than in the PG. (2:1 ± 2:4 vs. 8:5 ± 7:0, p < 0:05)Conclusions: Bepridil prevented the shortening of the ERP and MAPD90 induced by rapid atrial pacing in the acute phase. The results of this study might explain the efficacy of bepridil for preventing the recurrence of paroxysmal AF.
Variation in Lead Impedance according to Pacemaker Analyzing Systems
Authors: Ichiyanagi Hiroshi , Shiga Yoshiko , Ooiwa Noriaki , Nishiki Kazue , Hara Kimiko , Sato Yuki , Hayashi Hiroki , Inden Yasuya 
Published: August 2012

Background: The pacing lead system is electrically evaluated by a pacing system analyzer (PSA) during device implantation. However, it remains unknown whether measured data vary according to the PSA or the implantable device. We estimated differences in lead impedance measured by different PSAs and devices using a laboratory model.Methods: Five pacing and 3 defibrillation leads were used. We fixed the lead tip to a piece of meat immersed in physiologic saline and measured lead impedance using 4 PSA and 13 implantable device models.Results: The mean impedance of the 5 pacing leads as measured by PSAs was 735 to 611 ohms and the difference between the maximum and minimum values was 126 ohm. The maximum difference according to PSAs was 222 ohm. The mean impedance of the 5 pacing leads as measured by the implantable generators was 770 to 606 ohms, the difference was 175 ohms and the maximum difference was 309 ohms. The 3 defibrillation lead impedances varied from 427 to 1091 ohms and the mean impedance was 706 to 557 ohms. The differences were 149 ohm as measured by the PSAs and 157 ohms by the implantable cardioverter defibrillator (ICD) generators. The maximum differences were 241 ohms by the PSAs and 281 ohms by the ICD generators.Conclusion: Lead impedance varied according to analyzing systems.
Management of Patients Receiving Warfarin during Invasive Procedures and the Adverse Effects of Warfarin
Authors: Watanabe Norikazu , Tanno Kaoru , Ito Haruyuki , Onuki Tatsuya , Miyoshi Fumito , Minoura Yoshino , Kawamura Mitsuharu , Asano Taku , Katagiri Takashi , Kobayashi Youichi 
Published: August 2012

Aim: The aim of this study was to assess the frequency and characteristics of complications in patients on anticoagulant therapy who were to undergo invasive procedure.Methods and Results: We sent a questionnaire to 2758 doctors who were on the mailing list of the Japanese Society of Cardiac Pacing and Electrophysiology in August 2004. We received 614 questionnaires (response rate, 22.3%). Out of the 614 doctors, 19 (3.1%) reported that their patients had embolic events upon the interruption of warfarin therapy during dental extraction. In patients undergoing invasive procedures such as surgery, endoscopy, pacemaker implantation, and catheterization, 168 (27.4%) of the 614 doctors reported embolic events after the interruption of warfarin therapy. Further, 255 (41.5%) of the 614 doctors reported bleeding episodes when warfarin therapy was continued during the invasive procedures.Conclusion: Several complications of different types were reported to occur in patients receiving warfarin therapy who underwent elective invasive procedures, regardless of whether warfarin administration was interrupted or continued at the time of the invasive procedure. Therefore, it is necessary to make careful decisions about the management of patients on warfarin therapy who will be undergoing invasive procedures.
Rapid Improvement and Long‐term Stability of Pacing Threshold with Active‐fixation Screw‐in Lead
Authors: Sekita Gaku , Nakazato Yuji , Hayashi Hidemori , Hirano Keiko , Sugihara Masami , Yamase Miki , Komatsu Kaoru , Suzuki Takeshi , Kawano Yasunobu , Tokano Takashi , Sumiyoshi Masataka , Daida Hiroyuki 
Published: August 2012

Background: Active‐fixation screw‐in leads are associated with initially high thresholds. However, pacing thresholds have been shown to improve within several minutes after screwin. The aim of this study is to investigate the long‐term stability of rapidly improved pacing thresholds following the implantation of active‐fixation screw‐in leads.Methods: We performed a prospective observational study on 68 consecutive patients, who were referred for an initial pacemaker or implantable cardioverter defibrillator implantation. Pacing thresholds, sensing amplitudes, and lead impedances were measured immediately after screw‐in. If the initial pacing threshold was higher than 2.0 volts, lead reposition was performed. If the initial pacing threshold was lower than 1.0 volts, the lead position was considered adequate. If the initial pacing threshold was slightly high, i.e., between 1.0 and 2.0 volts, all parameters were measured again 5 minutes after screw‐in without lead repositioning, and 1 week, 1 month, 6 months, and 1 year after the procedure.Results: Fifty‐three atrial leads and 59 ventricular leads were implanted using activefixation screw‐in leads. The initial pacing threshold was slightly high, i.e., between 1.0 and 2.0 volts in 16 (30%) atrial leads and 28 (47%) ventricular leads. Pacing thresholds significantly improved after 5 minutes in both atrial and ventricular leads as follows: 1:5 ± 0:2 to 0:9 ± 0:3 volts (p < 0:05) in atrial leads and 1:5 ± 0:3 to 0:9 ± 0:3 volts (p < 0:05) in ventricular leads. These improved pacing thresholds remained stable during the first year and were 0:8 ± 0:3 volts in atrial leads and 0:8 ± 0:2 volts in ventricular leads after the initial year. P‐ and R‐wave amplitudes did not change significantly during the follow‐up. Lead impedances decreased 1 week after the procedure and remained stable in both atrial and ventricular leads.Conclusions: Slightly high pacing thresholds using active‐fixation screw‐in leads improved rapidly and remained stable in the long term. An acute pacing threshold of <2:0 volts immediately after screw‐in may change to an acceptable value without lead repositioning.
Summary of the Abstracts Contents at Cardiostim 2010
Authors: Ritter Philippe 
Published: August 2012

Cardiostim is a congress dedicated to devices, interventional electrophysiology and noninvasive electrophysiology. It was born in 1978, and imagined by Dr Jacques Mugica for educational purposes, and is held traditionally in Nice, French Riviera, on even years. This 2010 edition had 5700 participants coming from 92 countries. A large Japanese attendance was present and two joint sessions were organized with the Japanese Heart Rhythm Society.The program was divided into three sections: updates, education, and presentations based on selected submitted abstracts.Following is a summary of these selected abstracts, which does reflect the trends of our specialty, and of technological advances. For devices, telemedicine, MRI compatibility, full automaticity were the main topics. In cardiac pacing, respect of spontaneous AV conduction is confirmed as being essential, and positioning of the right ventricular lead remains an issue. For ICDs, better definition of candidates, utility of DFT testing, and reduction in inappropriate shocks are the main concerns. In CRT, extension of indications toward earlier stages of HF, implementation of hemodynamic sensors, and new approaches to the left ventricle are at the first row.Ablation techniques benefit from new technologies: interest and limits of cryo‐ablation, new radio‐frequency catheters, visualization of ablative lesions, contact control, and use of imaging techniques. The goals are: to speed up procedures, make them safer, and more efficient.