Search Results
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Kikuchi Hirotoshi H Department of Internal Medicine, Teikyo University School of Medicine , 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605 , - - 2003
Abstract We describe the case of a 29-year-old woman with systemic lupus erythematosus (SLE), who developed congestive heart failure and severe axonal polyneuropathy after 9 months of treatment with alfacalcidol for the prevention of corticosteroid-induced osteoporosis. There was no evidence for the exacerbation of SLE. Moreover, both congestive heart failure ...
Wu Zhong-Kai - - 2003
OBJECTIVE: The authors sought to establish whether regional ischemic preconditioning (IP) reduces ischemic reperfusion arrhythmias in patients who undergo off-pump coronary artery bypass grafting (OPCAB). DESIGN: A controlled, randomized, prospective study. SETTING: A university hospital. PARTICIPANTS: Thirty-two patients with left anterior descending coronary artery (LAD) or 2-vessel heart disease (including ...
Leenhardt Antoine - - 2003
This study was performed to examine precursors of ventricular tachyarrhythmias in patients who experienced a sustained ventricular tachyarrhythmia and received appropriate therapy by ICD. From an overall consecutive population of 77 patients, 18 patients (1 woman, mean age 61.7 +/- 10.8 years) were selected for having experienced a sustained ventricular ...
Kouakam Claude - - 2003
The incorporation of antitachycardia pacing (ATP) into implantable cardioverter defibrillators (ICDs) has provided a better tolerated alternative to shocks. ATP has been shown to be effective in terminating approximately 80% to 90% of spontaneous ventricular tachycardia (VT) episodes. Although ATP is routinely used, little is known about predictors of ATP ...
Valderrábano Miguel - - 2003
BACKGROUND: Multiple excitation wavelets are present during ventricular fibrillation (VF). The underlying wavelet organization of VF is unclear. Phase singularities (PSs)-locations of ambiguous activation state-underlie reentry and wavelet splitting and represent the sources of VF. Understanding the mechanisms of PS formation might be important in the development of effective therapies ...
Reddy Vivek Y - - 2003
OBJECTIVES: We evaluated the safety and acute procedural efficacy of a combined electrophysiologic and anatomic approach to ablation of all inducible ventricular tachycardias (VT) during sinus rhythm using an irrigated radiofrequency (RF) ablation catheter. BACKGROUND: Ventricular tachycardia associated with chronic myocardial infarction (MI) is frequently hemodynamically intolerable and associated with ...
Hohnloser Stefan H - - 2003
OBJECTIVES: This study was designed to evaluate the ability of microvolt-level T-wave alternans (MTWA) to identify prospectively patients with idiopathic dilated cardiomyopathy (DCM) at risk of ventricular tachyarrhythmic events and to compare its predictive accuracy with that of conventional risk stratifiers. BACKGROUND: Patients with DCM are at increased risk of ...
Gerstenfeld Edward P - - 2003
OBJECTIVES: The purpose of this study was to objectively quantify the similarity of 12-lead electrocardiogram (ECG) waveforms using two quantitative metrics, the correlation coefficient (CORR) and the mean absolute deviation (MAD). BACKGROUND: Comparison of the 12-lead ECG morphology between ventricular tachycardia (VT) and a pace-map is frequently performed; however, there ...
Veenhuyzen G D - - 2003
Traditionally, myocardial ischemia, electrolyte disorders, and proarrhythmic drug reactions have been considered transient and correctable causes of life threatening ventricular tachyarrhythmias. Recent evidence suggests that patients whose ventricular tachyarrhythmias are attributed to these "causes" have a poor outcome. This overview reviews the available literature examining ischemia, electrolyte disorders and pro-arrhythmic ...
Pappone Carlo - - 2003
Biventricular pacing (BVP) improves hemodynamics and symptoms in patients with heart failure with bundle branch block. Patients with a left ventricular ejection fraction <0.35 and ventricular tachyarrhythmias are at risk of sudden cardiac death, and they benefit most from implantable cardioverter defibrillators (ICDs). No study has evaluated the efficacy of ...
Kassotis John - - 2003
Most wide-complex tachycardias encountered in the emergency department (ED) are ventricular in origin, most commonly associated with structural heart disease. Ventricular tachyarrhythmias range in severity from life-threatening rhythms (eg, ventricular fibrillation and hemodynamically compromising ventricular tachycardia [VT]) to idiopathic forms of VT, which have a benign clinical course and a ...
Xing Dezhi - - 2003
INTRODUCTION: The aim of this study was to determine if the stable antiarrhythmic peptide (AAP) analogue ZP123 increases gap junctional intercellular conductance and prevents reentrant ventricular tachycardia (VT) during coronary artery occlusion. METHODS AND RESULTS: Voltage clamp experiments demonstrated that 10 nM ZP123 improved gap junctional intercellular conductance by 69% ...
Terai Hidenobu - - 2003
Malignant ventricular tachyarrhythmia (VT) and sudden death are serious events in hypertrophic cardiomyopathy (HCM). However, the pathophysiology of this condition is not well understood. The objective of this study was to evaluate the relationship between cardiac sympathetic nerve activity and the occurrence of VT in HCM patients. Methods and results ...
Morita Hiroshi - - 2003
INTRODUCTION: It has been believed that electrophysiologic abnormality of the epicardial region of the right ventricular free wall may play an important role in arrhythmogenesis of phase 2 reentry in Brugada syndrome, but clinical evidence of the occurrence of ventricular arrhythmias at the right ventricular free wall has not been ...
Saba Samir - - 2003
BACKGROUND: End-stage heart failure (HF) patients are at high risk of sudden cardiac death. This study evaluates the role of implantable cardiac defibrillators (ICDs) in HF patients awaiting cardiac transplantation. METHODS: We identified 194 consecutive patients (age 51 +/- 12 years) with New York Heart Association Class 3 or 4 ...
Gopalakrishnan Meera - - 2003
Cardiac arrhythmias are undesirable electrical activity in the heart. Ventricular fibrillation (VF) is a fatal cardiac arrhythmia and is characterized by the breakdown of organized electrical activity in the ventricular myocardium. However, little is known about VF, partially because it is difficult to study and understand an apparently disorganized activity. ...
Brunckhorst Corinna B - - 2003
OBJECTIVES: This study sought to characterize the relationship of conduction delays detected by pace-mapping, evident as a stimulus to QRS interval (S-QRS) delay >or=40 ms, to ventricular tachycardia (VT) re-entry circuit isthmuses defined by entrainment and ablation. BACKGROUND: Areas of slow conduction and block in old infarcts cause re-entrant VT. ...
Al-Khatib Sana M - - 2003
BACKGROUND: In many patients, ventricular arrhythmias will develop early after acute myocardial infarction. We studied the incidence, timing, and outcomes of such arrhythmias in the international Global Utilization of Streptokinase and TPA (alteplase) for Occluded Coronary Arteries (GUSTO)-III trial. METHODS: We identified independent predictors of inhospital ventricular fibrillation (VF) and ...
Kozák Milan - - 2003
A circadian distribution has been demonstrated in episodes of sudden cardiac death, acute myocardial infarction, ventricular premature complexes, heart rate variability, and ventricular tachyarrhythmias. The aim of this study was to evaluate the circadian distribution of ventricular tachyarrhythmia episodes in a population of ICD patients. Data were gathered from 72 ...
Zaitsev Alexey V - - 2003
Both fixed and dynamic heterogeneities were implicated in the mechanism of wavebreak (WB) generation during ventricular fibrillation (VF). However, their relative roles remain unclear. We hypothesized that during ischemic VF, the WBs are produced primarily because of a fixed heterogeneity; namely, the gradient of refractoriness across the ischemic border zone ...
Bailin Steven J - - 2003
INTRODUCTION: Despite continuing advances, inappropriate implantable cardioverter defibrillator (ICD) therapies in response to nonventricular tachyarrhythmias continue to cause patient discomfort and increased follow-up demands. METHODS AND RESULTS: We investigated the performance of a new dual-chamber ICD (Photon DR, St. Jude Medical), with specific attention to its arrhythmia discrimination and detection ...
Cavusoglu Yuksel - - 2003
Reversible myoglobinuric renal failure following rhabdomyolysis that was related to repeated countershocks delivered for the treatment of refractory recurrent VT and VF attacks during acute myocardial infarction is presented in this case report, in which scan with technetium-99m pyrophosphate has been used for in the diagnosis of extensive skeletal muscle ...
Naik Nitish - - 2003
Recognising ventricular origin of a broad QRS tachycardia helps to appropriately identify and manage patients with ventricular tachycardia (VT) in the emergency. Relatively simple clinical and ECG clues help in reaching the correct diagnosis in the majority of patients. Management strategies vary with the clinical diagnosis and an implantable cardioverter ...
Kawahara Koichi - - 2003
INTRODUCTION: The relationship between vulnerability to reperfusion-induced ventricular tachyarrhythmias, such as ventricular tachycardia (VT) and fibrillation (VF), and the endogenous activity of nitric oxide synthase (NOS) has not been well documented. The objective of the present study was to clarify whether the vulnerability to reperfusion-induced VT/VF changes with preishemic, sustained ...
Kudaiberdieva Gulmira - - 2003
The authors investigate incidence of ventricular tachycardia/ventricular fibrillation (VT/VF) in relationship with combination of noninvasive arrhythmia risk markers as left ventricular ejection fraction (LVEF), late potentials (LP), and QT variability index (QTVI) and compare the utility of their combination in association with sustained ventricular arrhythmias in patients after myocardial infarction ...
Dixit Sanjay - - 2003
INTRODUCTION: The superior right ventricular outflow tract (RVOT) septum and free wall are common locations of origin for outflow tract ventricular tachycardias (VT). We hypothesized that (1) unique ECG morphologies of pace maps from septal and free-wall sites in the superior RVOT could be identified using magnetic electroanatomic mapping for ...
Rojo-Alvarez J L - - 2003
AIMS: Ventricular activation onset is faster in supraventricular beats than in ventricular rhythms. The aim of this study was to evaluate a criterion to differentiate supraventricular (SVT) from ventricular tachycardia (VT) based on the analysis of the initial voltage changes in ICD-stored morphology electrograms. METHODS: Far field ICD-stored EGMs were ...
Kautzner Josef - - 2003
One challenge encountered during catheter ablation of postinfarction ventricular tachycardia (VT) is the inducibility of multiple VT morphologies associated with variable hemodynamic instability. The clinical usefulness and safety of a three-dimensional electroanatomical mapping in guiding radiofrequency (RF) catheter ablation of VT, used in parallel with a multichannel recording system, was ...
Grimm Wolfram - - 2003
This study investigated the relation between heart rate variability (HRV) measured as standard deviation of normal to normal RR intervals (SDNN) on baseline 24-hour ambulatory electrocardiogram (ECG) and subsequent appropriate implantable cardioverter defibrillator (ICD) interventions in 70 patients with idiopathic dilated cardiomyopathy (IDC) in whom ICDs were implanted prophylactically in ...
Burke Martin C - - 2003
We are developing a subcutaneous cardiac arrest monitor and alarm with electrodes that have spacing of a few centimeters. We hypothesize that closely spaced bipolar electrodes that provide QRS amplitudes of a millivolt or more in sinus rhythm (SR) will not provide similar amplitudes during ventricular tachyarrhythmia (VT/VF), and that ...
Fauchier Laurent - - 2003
Biventricular pacing is a new form of treatment for patients with dilated cardiomyopathy and ventricular dyssynchrony. Limited information is available regarding the relationship between ventricular dyssynchrony and risk markers of ventricular arrhythmias in idiopathic dilated cardiomyopathy (IDC). In 103 patients with IDC, Fourier phase analysis of both ventricles was performed ...
Laohakunakorn P - - 2003
Experience concerning radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) in pediatric patients is limited. In adults, success rates vary widely based on the etiology of the VT. Highest success rates have been achieved in patients without structural heart disease. Between March 1998 and December 1999, five young patients (age, ...
Nogami Akihiko - - 2002
Idiopathic left ventricular tachycardia (VT) has been classified into three subgroups according to mechanism: verapamil-sensitive, adenosine-sensitive, and propranolol-sensitive types. VT can be categorized also into left fascicular VT and left outflow tract VT. Although the mechanism of fascicular VT is verapamil-sensitive reentry, the mechanism of left outflow tract VT is ...
Jekova Irena - - 2002
The recent development and increased application of automatic external defibrillators have prescribed very strong requirements towards ventricular fibrillation (VF) and fast ventricular tachycardia (VT > 180 bpm) detection from the surface electrocardiogram (ECG). We attempted to use informative parameters from several existing analysis methods and from a method developed in-house. ...
Okajima Katsunori - - 2002
The clinical significance of induced nonclinical ventricular tachycardia (NCVT) in nonischemic dilated cardiomyopathy (DCM) remains controversial. Twenty-eight patients with sustained VT or ventricular fibrillation related to DCM underwent programmed ventricular stimulation (PVS) to induce VT. However, VT was not induced in four patients. Based on the morphology of induced ventricular ...
Lacroix Dominique - - 2002
VT late after myocardial infarction usually originates from the endocardial surface; subepicardial substrates are also possible. The identification of these atypical locations with endocardial mapping remains unresolved even with new mapping technologies. This study compared isopotential maps, signal morphology, and activation patterns around left endocardial breakthroughs recorded in VTs originating ...
Gupta Anoop K - - 2002
Fascicular VT and RVOT tachycardia are sometimes difficult to induce by programmed electrical stimulation (PES), despite pharmacologic provocation. In such instances, catheter mapping is hampered and efficacy of catheter ablation is difficult to judge. The study included nine patients who presented with incessant idiopathic VT and were directly taken to ...
Igawa Masayuki - - 2002
In recent clinical trials, class III anti-arrhythmic drugs were found to reduce arrhythmic deaths in patients after myocardial infarction. The purpose of this study was to assess the electrophysiologic properties and anti-arrhythmic efficacy for inducible sustained ventricular tachycardias (VTs) of the pure class III agent nifekalant hydrochloride (MS-551) in comparison ...
Gold Michael R - - 2002
INTRODUCTION: Discrimination of ventricular and supraventricular arrhythmias remains one of the major challenges for appropriate implantable defibrillator (ICD) therapy delivery. The electrogram vector timing and correlation (VTC) algorithm was developed for such rhythm discrimination. The VTC algorithm differentiates normally conducted supraventricular beats from abnormally conducted ventricular beats by comparing the ...
von Oppell Ulrich Otto - - 2002
OBJECTIVES: To review 26 consecutive patients with sustained monomorphic ventricular tachycardia (VT) of left ventricular origin, who underwent direct VT surgery. METHODS: Economic factors precluded the use of an implantable cardioverter defibrillator (ICD) in the majority of these patients, and the indication for surgery in 81% of patients was for ...
Kühlkamp Volker - - 2002
Implantable cardioverter defibrillator (ICD) therapy is used frequently in patients with "slow" ventricular tachycardia (VT). Hence, the tachycardia detection interval is programmed within the range of the physiologic heart rate, but this may cause serious problems. If a fast VT is converted to sinus tachycardia with a cycle length shorter ...
Swarup Vijendra - - 2002
Characterization of the substrate and mechanism of epicardial ventricular tachycardia (VT) associated with idiopathic nonischemic dilated cardiomyopathy is limited. We report a case of successful mapping and ablation of an epicardial VT by a percutaneous transthoracic approach in a patient with idiopathic dilated cardiomyopathy, frequent VT, and previously unsuccessful endocardial ...
Korhonen Petri - - 2002
BACKGROUND: Delayed electrical activity necessary for re-entrant ventricular tachycardia (VT) is detectable noninvasively with high resolution techniques. We compared high resolution signal-averaged analysis of magnetocardiography (MCG), body surface potential mapping (BSPM), and orthogonal three-lead ECG (SA-ECG) in the identification of patients prone to VT after myocardial infarction (MI). METHODS: Patients ...
Koyama Jiro - - 2002
The significance of heart-rate turbulence (HRT) in patients with chronic heart failure (CHF) was evaluated to examine whether it is sensitive to the risk of ventricular tachycardia (VT). HRT is reported to predict the prognosis after myocardial infarction (MI), but its prognostic value in patients with CHF remains unknown. HRT ...
Soejima Kyoko - - 2002
BACKGROUND: We hypothesized that delineating electrically unexcitable scar (EUS) within low-voltage infarct regions will locate reentry circuit isthmuses by defining their borders. The pacing threshold and electrogram amplitude that best determines EUS is unknown. METHODS AND RESULTS: The change in dimension of the virtual electrode was estimated in 11 patients ...
Kitamura Hidetsuna - - 2002
INTRODUCTION: Gap junction alterations recently have been implicated in chronic heart failure, but direct evidence between gap junction manifestation in nonischemic dilated cardiomyopathy (DCM) is lacking. The current study examines whether qualitative changes or altered distribution of gap junctional connexin43 (Cx43) are related to global ventricular function and ventricular arrhythmia ...
Healy Edward - - 2002
A 58-year-old man with an ischemic cardiomyopathy underwent ICD implantation after having an electrophysiological study positive for inducible, sustained monomorphic VT. Approximately 1 week later he experienced a shock. Inspection of stored electrograms revealed that a run of nonsustained VT had initiated his ICD to charge. The episode spontaneously terminated, ...
Vittrup Axel - - 2002
OBJECTIVE: Holter monitoring is one option in risk-stratification after acute myocardial infarction (MI). Measurements of heart rate variability (HRV), ventricular tachycardia (VT) and ST-segment elevation (ST upward arrow ) have been useful in predicting clinical outcome. We investigated if a combination of different Holter variables could optimize risk-stratification. DESIGN: One ...
Lee Shih-Huang - - 2002
The aim of the study was to define the factors that may predict the outcomes of radiofrequency ablation from the right ventricular outflow tract (RVOT) in patients with idiopathic VT with a QRS morphology of LBBB. Endocardial mapping and RF ablation from the RVOT were performed in 35 patients (14 ...
Duke Christopher - - 2002
This report describes an adolescent who presented with ventricular tachycardia (VT) originating from the right ventricular apex, with no apparent underlying cause. Cardiac sarcoidosis was identified only at postmortem examination after sudden death. There must be a high index of suspicion for subtle forms of primary myocardial abnormalities in such ...
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