bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ablation of Idiopathic Ventricular Tachycardia with a Left Bundle‐Branch Block Morphology Originating from the Pulmonary Artery
Authors: Ogi Hiroshi , Nakano Yukiko , Oda Noboru , Miyoshi Miwa , Chayama Kazuaki , Ishibashi Ken , Hirai Yuko , Okimoto Tomokazu 
Published: August 2012

AbstractWe successfully performed radiofrequency catheter ablation (RFCA) in 2 cases involving patients with idiopathic ventricular tachycardias (VTs) and premature ventricular contractions (PVCs) originating from the pulmonary artery (PA). The QRS morphology of the VTs and PVCs in the two cases exhibited a left bundle‐branch block (LBBB) morphology with an inferior axis. Activation and pace mappings were performed in the right ventricular outflow tract (RVOT) and above the pulmonary valve to determine the origin of the VTs and PVCs. In both cases, the earliest ventricular activation was recorded in the PA above the pulmonary valve. Applications of radiofrequency current at those sites in the PA resulted in the elimination and noninducibility of the VT and PVC. During the follow‐up, the VT or PVC did not recur without any antiarrhythmic drug administration.
Sinus Bradycardia with Heart Rate Lower than the Programmed Lower Rate Limit in a Patient with an Implanted VDD Pacemaker
Authors: Suzuki Satoru , Hashizume Kenichi , Kanki Hideaki , Harada Shigeru 
Published: August 2012

AbstractThe authors present a case report of a patient with an implanted VDD pacemaker whose postoperative ECG revealed sinus bradycardia, showing the heart rate remarkably lower than the programmed lower rate limit. Upon assessing some pacemaker manufacturers' mechanisms to set the lower rate limit in VDD mode, it was found that they can be classified into four types. The mechanisms are based on keeping atrioventricular (AV) synchronous pacing in VDD mode or maintaining the lower rate limit in VVI mode. AV synchronous pacing results in producing an actual heart rate which is lower than the programmed lower rate limit. The classification also depends on whether the pacemakers are operating on either atrial‐based or ventricular‐based lower rate timing. Therefore, the actual heart rate can be lower than the programmed lower rate limit, depending on the VDD pacemaker model.
Diagnosis and Treatment of Syncope
Authors: Kobayashi Youichi 
Published: August 2012

AbstractAccurate diagnosis of syncope is essential because it ranges from cardiac syncope with a very poor prognosis to neurally‐mediated syncope (NMS) with a relatively favorable prognosis. Diagnosis of syncope, however, is difficult in many patients even by HUT, so a new loading method for HUT or implanted Holter ECG monitoring will be required in the future. The prognosis of NMS itself may be favorable, but it may cause the aggravation of complications.
Long‐Term Follow‐Up of Endocardial Pacing Leads Implanted with Extrathoracic Subclavian Venous Approach
Authors: Ohnuki Masahiro , Miyataka Kazuhiko , Nakamura Takehiko , Ohnishi Yoshinobu , Kohnoike Yoshizumi , Tsujimoto Masayuki , Shirayama Reirou 
Published: August 2012

AbstractThe extrathoracic subclavian venous approach is a new approach with the aim to exclude the disadvantages of the conventional subclavian venous approach that carries a risk of pneumothorax and may result in lead damage. We investigated long‐term survival of the leads implanted by this new approach between May 1995 and June 2005. A total of 482 leads implanted in 309 patients were analyzed. In cases of patient death, meeting criteria for lead failure or difficulty of continuing follow‐up for other reasons, the follow‐up was terminated at that time. Therefore, the follow‐up was complete for 358 leads (74.3%) and the mean followup time was 55.0 ± 32.1 months (range 1–122 months). The overall lead survival rate was 100% at 5 years and 98.3% at 7 years. This finding suggested that this approach might reduce the incidence of lead failure.
Common Trunk of the Inferior Pulmonary Veins in a Patient with Paroxysmal Atrial Fibrillation
Authors: Miyanaga Satoru , Date Taro , Yamane Teiichi , Inada Keiichi , Shibayama Kenri , Matsuo Seiichiro , Miyazaki Hidekazu , Kanzaki Yasuko , Sugimoto Ken‐ichi , Mochizuki Seibu 
Published: August 2012

AbstractHerein we report a case of a patient presenting with paroxysmal atrial fibrillation (PAF) in whom the pulmonary veins (PVs) had a common inferior trunk and PV isolation at the common inferior trunk was successfully performed to prevent recurrence of PAR A 58‐year‐old man with drug‐resistant PAF was referred to undergo curative treatment at our institution. A three‐dimensional image of the PVs re‐constructed by contrast‐enhanced multi‐detector computed tomography before the operation revealed a common inferior trunk of the PVs (24mm diameter). Segmental ostial PV isolation with the guidance of a circular mapping catheter was performed for both superior PVs and the common inferior PV trunk. All three PV ostia were successfully isolated from the LA, and the patient has been free from PAF thereafter for 18 months. Preprocedural multi‐detector computed tomography or magnetic resonance imaging to evaluate the anatomy of PVs (the number, size, and shape) is thus considered to be useful for performing safe and smooth catheter ablation in patients with PAR
Arrangement of the Autonomic Nerves Around the Pulmonary Vein‐Left Atrial Junctions —Histologic and Immunohistochemical Analyses—
Authors: Matsuyama Taka‐aki , Inoue Shin , Kobayashi Youichi , Makino Mutsuki , Sakai Tetsuo , Saito Tsukasa , Asano Taku , Tanno Kaoru , Katagiri Takashi , Ota Hidekazu 
Published: August 2012

Introduction: Imbalanced autonomic activity in the area of the pulmonary veins (PVs) can result in spontaneous atrial fibrillation (AF). Histologic characteristics of the PV sleeve musculature and associated autonomic nerve are not fully understood. We investigated the arrangement of autonomic nerve fibers around PV‐left atrium (LA) junctional musculature.Methods: Thirteen autopsied adult hearts (9 men and 4 women; mean age at death, 66.2 years were studied. The atria were removed from each heart, along with all PV stalks, and cut longitudinally to each PV myocardial sleeve. After treatment with azan‐Mallory stain and immunohistochemical staining for S‐100 and tyrosine hydroxylase (TH), autonomic nerve distribution was assessed by counting the numbers of TH‐positive (adrenergic and ‐negative (non‐adrenergic) fibers within S‐100‐positive fibers (>50 mm in diameter) in the anterior, posterior, and septal junctions.Results: TH‐positive adrenergic fibers, consisting of sympathetic nerves, were most predominant in the anterior and septal junctions. In the anterior junction, these fibers were packed tightly among myocardial sleeve fascicles. In the posterior junction, the numbers of adrenergic and non‐adrenergic fibers were fewer. In the septal junction, the number of THnegative non‐adrenergic fibers (predominantly parasympathetic nerves) was greater, concomitant diffuse ganglionic nodule distribution in the interatrial fat pad.Conclusions: In each PV‐LA junction, autonomic nerves were localized on the anterior and septal walls. Heterogeneous distribution of TH‐positive and TH‐negative fibers and ganglion nodules around each PV opening appears to represent the major histologic characteristic in these areas.
QT Interval Revisited —Not Just the Matter of “Interval,” but “Dynamics, Variability and Morphology” Matter!—
Authors: Saikawa Tetsunori , Nakagawa Mikiko , Takahashi Naohiko 
Published: August 2012

Recently, the effects of QT interval prolongation have received more attention among clinicians, industry, and official regulatory agencies. Some have advocated the total elimination or discontinuing development of drugs which prolong the QT interval. In this review, we will give a brief overview of the pathophysiology and the dynamic variability and morphology of the QT interval. From the view point of arrhythmogenesis, QT interval prolongation with increased heterogeneity of ventricular repolarization is critical. The problem is how to detect such an abnormal repolarization. To detect heterogeneity, a new index should be developed and validated, and it must incorporate QT variability and morphology of the T wave. The heart rate correction of the QT interval is also an important issue, and disclosing conflict‐corrected QT intervals depend on the formulae used.Not just QT interval prolongation is important; what also matters is the heterogeneity of ventricular repolarization.
Efficacy and Safety of Catheter Ablation for Persistent or Permanent Atrial Fibrillation
Authors: Muraoka Soichi , Mitsutake Chiharu , Takashima Hideo , Nakashima Hideko , Yasuda Tomoo , Matsumoto Naomichi , Kumagai Koichiro , Saku Keijiro 
Published: August 2012

Introduction: Radiofrequency catheter ablation (RFCA) that targets pulmonary veins (PV) is an established treatment for paroxysmal atrial fibrillation (PAF). Recent studies have demonstrated that RFCA can eliminate PAF in over 90% of patients. However, the effectiveness for persistent or permanent AF has not been clarified.Methods and Results: 27 patients (29%) had persistent or permanent AF. RFCA including PV antrum isolation (PVAI) was performed using a circular mapping catheter in the patients with persistent or permanent AF. Four patients (15%) underwent only PVAI. Thirteen patients (48%) underwent PVAI and left atrium roof and/or mitral isthmus linear ablation. Ten patients (37%) underwent PVAI and RFCA to an area with complex fractionated atrial electrograms. All patients were observed for over a year. After repeat ablation at mean followup of 16 ± 5 months, 23 patients (85%) had normal sinus rhythm and were free of symptomatic AF or atrial flutter. Three patients required antiarrhythmic drugs to maintain sinus rhythm during follow‐up period. One patient had a transient phrenic nerve injury. Two patients were documented with sustained atrial tachycardia (AT). Mapping in 2 patients showed a macro reentry AT due to gaps in the ablation lines and further ablation was needed. No other complications including PV stenosis occurred.Conclusions: The present study demonstrated that RFCA is an effective and feasible treatment for persistent or permanent AF.
Atrioventricular Pacemaker Lead Reversal
Authors: Aktas Mehmet K , Shah Abrar H , Akiyama Toshio 
Published: August 2012

AbstractDuring cardiac surgery temporary epicardial atrial and ventricular leads are placed in case cardiac pacing is required postoperatively. We present the first reported series of patients with reversal of atrioventricular electrodes in the temporary pacemaker without any consequent deleterious hemodynamic effect. We review the electrocardiographic findings and discuss the findings that lead to the discovery of atrioventricular lead reversal.
Efficacy and Safety of Intravenous Amiodarone Infusion in Japanese Patients with Hemodynamically Compromised Ventricular Tachycardia or Ventricular Fibrillation
Authors: Katoh Takao , Ogawa Satoshi , Yamaguchi Iwao , Kasanuki Hiroshi , Hayakawa Hirokazu 
Published: August 2012

Introduction: Amiodarone infusion has been recommended for life‐threatening ventricular arrhythmias. However its effectiveness in Japanese patients has not yet been determined.Methods: This was an uncontrolled, open‐label trial involving patients with hemodynamically unstable ventricular tachycardia (VT) or ventricular fibrillation (VF). Intravenous amiodarone was delivered as a 125 mg bolus followed by infusion of 50 mg/h for 6 hours, then 25 mg/h for 42 hours. The primary endpoint for efficacy was the proportion of patients free from hemodynamically unstable VT/VF at 48‐hour. Secondary endpoints included: event frequency; proportion of patients event‐free, treatment outcome, and safety.Results: Forty‐seven patients were enrolled. Forty‐one patients were evaluated for efficacy and safety parameters were assessed for all 47 patients. The proportion of patients free from hemodynamically unstable VT/VF was 53.9%; the proportion of patients free from hemodynamically unstable VT/VF relapse or whose treatment was discontinued was 48.8%. Eight patients died; all deaths were judged, by the investigator, as being unrelated to amiodarone. No cases of torsades de pointes were reported. Mild abnormal thyroid function was noted in one patient. No cases of interstitial lung disease or pulmonary fibrosis were observed.Conclusion: Amiodarone infusion provides a useful tool in preventing acute relapse of lifethreatening ventricular arrhythmias in Japanese patients.
Critical Slow Conduction Zone Located between the Tricuspid Annulus and a Myocardial Infarct Scar in a Patient with Multiple Ventricular Tachycardia Late after Myocardial Infarction
Authors: Nakano Emi , Harada Tomoo , Nakazawa Kiyoshi , Osada Keizou , Takagi Akihiko , Sasaki Toshio , Yoneyama Kihei , Wakimoto Hirofumi , Tanaka Osamu , Mizuno Kouichi , Azuma Nobuyuki , Kishi Ryouji , Miyake Fumihiko 
Published: August 2012

A patient underwent an electrophysiological study (EPS) and catheter ablation (CA) for ventricular tachycardia (VT) that developed 11 years after myocardial infarction.Entrainment mapping (EM) of the left ventricle did not identify the origin of the VT during induction. Electro‐anatomical mapping revealed a low voltage area from the anterior to the inferior left ventricular wall. Another EPS was performed for right ventricular mapping.A basket catheter was placed in the right ventricle to evaluate impulse propagation and we attempted to identify the VT circuit with EM during the same VT (complete left bundle branch block configuration, inferior axis) as the previous EPS.Eight different VT appeared, three of which were sustained during CA. The reentry circuit exit was identified on the tricuspid annulus (TA) at the 9:00 site and radiofrequency (RF) ablation was performed, but the axis transformed from the inferior to the superior and another VT appeared. Despite RF ablation to the VT circuit exit at the 5:00 site, another sustained VT appeared. Finally, it was terminated by ablation to a critical slow conduction zone (SCZ) located near the 7:00 site one year later. Electro‐anatomical voltage mapping detected a critical isthmus between TA and right ventricle infarct scar.Here, we describe a rare SCZ proximal to the TA in a patient with VT late after myocardial infarction.
Long‐term Prognosis for Non‐ischemic Heart Disease Patients with Premature Ventricular Contraction and Non‐sustained Ventricular Tachycardia
Authors: Komoriya Masakazu , Imai Shinobu , Aoyama Hiroshi , Yagi Hideki , Nagashima Masaaki , Enomoto Mitsunobu , Suzuki Kazutaka , Yamaji Satoshi , Takase Hidehito , Matsudaira Kagari , Takahashi Naoyuki , Saito Fumio , Yagi Hiroshi , Kushiro Toshio , Nagao Ken , Hirayama Atsushi 
Published: August 2012

There are few long‐term reports of patients with frequent PVCs in the absence of ischemic heart disease. In 86 patients without ischemic heart disease, who had 1000 or more PVCs in 24‐hour Holter ECG, the number of PVCs during 24‐hours Holter ECG and echocardiographic parameters were followed at least 1 year (66.5 ± 39.7 months). PVC was significantly reduced in the patients with or without underlying diseases (UD). The reduction rate in the number of PVCs was prominent in patients with UD. PVC was significantly reduced in patients under medication, but not in patients without medication. In the comparison between the initial and follow up observation using Wilcoxon's rank test, the number of PVC was significantly reduced (P < 0.05), and EF was also improved (P < 0.05) in angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) group, and in β‐blocker group. In Ca‐antagonist group and antiarrhythmic drug group, the number of PVCs was also significantly reduced (P < 0.05). Multivariate analysis revealed significantly higher incidence (60% or more with PVC reduction) in ACEI/ARB group.These results suggest that the administration of ACEI/ARB may contribute to the reduction of PVC in non‐ischemic heart disease cases with multiple PVC.
Noncontact Mapping‐Guided Catheter Ablation of Posterosuperior Right Atrial Tachycardia Associated with Sick Sinus Syndrome
Authors: Yasuda Shioto , Nakamura Hirofumi , Karashima Eiji , Ueda Jin , Nakaji Gen , Shimazu Hideki , Hiramatsu Shin‐ichi , Odashiro Keita , Maruyama Toru , Kaji Yoshikazu 
Published: August 2012

Focal atrial tachycardia (AT) is sometimes associated with sick sinus syndrome. A 57‐year‐old female complained of palpitation, fatigue and presyncope. Ambulatory monitoring demonstrated frequent segments of AT and subsequent sinus arrests. P wave morphology of ectopic beats was similar to that of sinus rhythm. After obtaining diagnosis of bradycardia tachycardia syndrome, she underwent electrophysiologic study (EPS) and radiofrequency (RF) catheter ablation to eliminate AT.Conventional EPS could not be performed due to frequent spontaneous ectopic beats. EnSite mapping demonstrated that AT originates from posterosuperior right atrium (RA) and that local electrogram of ectopic focus precedes the onset of P wave in surface ECG by 40 msec. After EnSite‐guided RF ablation to the target area, ambulatory monitoring detected no AT or sinus arrest. EPS performed one week after RF ablation showed atropine‐induced partial restoration of sinus node dysfunction.Her symptoms were resolved remarkably and permanent pacemaker implantation has not been necessary to date. RF ablation guided by EnSite mapping was useful to eliminate AT arising from limited ectopic focus and this case implies existence of “pacemaker‐avoidable” bradycardia tachycardia syndrome.
Prolonged Asystole during Head‐Up Tilt Test in a Patient with Malignant Neurocardiogenic Syncope
Authors: Tokano Takashi , Nakazato Yuji , Sasaki Akitoshi , Sekita Gaku , Yasuda Masayuki , Sumiyoshi Masataka , Daida Hiroyuki 
Published: August 2012

A 27 year‐old man was taken to our emergency room after collapsing during a conference. The patient had a history of syncope twice since age 15. A marked sinus bradycardia and asystole were induced causing the patient to collapse when tested to stand up in the emergency room. Cardioinhibitory type neurocardiogenic syncope was considered to be the cause of the syncope. Therefore the patient was treated with oral disopyramide at a daily dose of 150 mg. Three weeks later, a head‐up tilt test was performed for evaluation of drug effectiveness. However, a prolonged asystole for 24 seconds due to sinus arrest without escape beat was induced 7 minutes after starting the tilt at 80 degrees. Although the tilt table was returned to the flat position immediately, it took an additional 30 seconds for complete recovery of the patient's consciousness.Malignant cardioinhibitory type neurocardiogenic syncope with a prolonged asystole such as was found in this patient has rarely been observed. Treatment options should be discussed if the patient refuses pacemaker implantation.
Current status of implantable defibrillator devices in patients with left ventricular dysfunction — The first report from the online registry database
Authors: Shimizu Akihiko , Nitta Takashi , Kurita Takashi , Imai Katsuhiko , Kimura Takeshi , Kobayashi Yoshinori , Soejima Kyoko , Niwano Shinichi , Watanabe Shigeyuki , Abe Haruhiko 
Published: August 2012

Background: The current status of the efficacy of implantable cardioverter‐defibrillator (ICD. and cardiac‐resynchronization therapy with implantable defibrillator (CRT‐D. in patients with left ventricular dysfunction needs to be clarified.Methods and Results: From the Japanese Cardiac Device Treatment Registry database, a total of 1,584 patients who had an LVEF ≦ 40% and had an ICD or CRT‐D were selected as subjects in this study. The difference in the clinical characteristics between the primary and secondary prevention groups and the transition of the indications for device implantation over time were examined. Primary prevention gradually increased up to about 50% in all patients. The implantations of ICD/CRT‐D for primary prevention in ischemic hear disease was significantly lower than that in dilated cardiomyopathy (33% vs 51%; p < 0.0001). The number of implantations for CRT‐D for primary prevention increased dramatically over a one‐year period.Conclusions: In Japan, the implantable defibrillator devices for primary prevention was significantly lower in ischemic heart disease compared with dilated cardiomyopathy. Further, an extension of the indications for ICD/CRT‐D implantations has recently been occurring, especially with CRT‐D devices for primary prevention.
Effect of nifekalant on life‐threatening ventricular arrhythmias in patients with cardiopulmonary resuscitation or during the perioperative state
Authors: Hirasawa Shoji , Niwano Shinichi , Kishihara Jun , Kiryu Michirou , Imaki Ryuta , Izumi Tohru 
Published: August 2012

Background: Nifekalant is a unique class III anti‐arrhythmic agent with a strong effect on prolonging the myocardial refractoriness, but its clinical effect is still unclear. In this study, we evaluated the effect of nifekalant on life‐threatening ventricular arrhythmias and compared the clinical background between the effective and non‐effective patients in order to clarify the clinical factors which may have an influence on the efficacy of nifekalant.Methods: The study population consisted of 47 consecutive patients who underwent nifekalant administration for life‐threatening ventricular arrhythmias (VT/VF). Their clinical characteristics and ECG parameters were retrospectively compared between patients with and without an effective result with the nifekalant administration.Results: Nifekalant was effective for refractory VT/VF in 26/47 patients. There was no significant difference in the age, gender or left ventricular ejection fraction, but the incidence of ischemic heart disease was higher in the effective group (17/26) than non‐effective group (9/21, p = 0.004). The incidence of in‐hospital events was higher in the effective group than non‐effective group (20/26 vs 10/21, p = 0.037). A significant prolongation in the QTc interval was observed in all patients and the degree of QTc prolongation was greater in the effective group than in the non‐effective group (0.46 ± 0.04 vs 0.43 ± 0.02 sec1/2, p = 0.026).Conclusion: Nifekalant was effective in 55% of the patients for refractory VT/VF. It was considered that nifekalant was more effective for patients with ischemic heart disease, during the perioperative period or in those experiencing in‐hospital events. The prolongation of the QTc interval might also be useful as an index for the efficacy of nifekelant administration.