Search Results
Results 401 - 450 of 1869
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Kühlkamp Volker - - 2002
An implantable defibrillator with dual chamber pacing may have advantages for pacing, sensing, and detection of brady- and tachyarrhythmias. This study evaluates the safety and performance of a dual chamber implantable cardioverter defibrillator that incorporates an algorithm to discriminate supraventricular from ventricular arrhythmias. The 300 patients in this study had ...
Menozzi Carlo - - 2002
BACKGROUND: In patients with syncope and structural heart disease, syncope is suspected to be attributable to a primary cardiac arrhythmia, but little is known of its mechanism when electrophysiologic study is unremarkable. METHODS AND RESULTS: We applied an implantable loop recorder in 35 patients with overt heart disease at risk ...
Germano Joseph J - - 2002
The case of an 87-year-old woman with a significant history of coronary artery disease illustrates the challenge associated with intractable ventricular tachycardias, and demonstrates the various options available for terminating and controlling the potentially fatal arrhythmia. A favorable outcome was obtained using advanced cardiac life support guidelines, current pharmacological regimens, ...
Boriani Giuseppe - - 2002
OBJECTIVE: To assess the haemodynamic effects of short-term treatment with dofetilide in comparison with sotalol in patients with ischaemic heart disease. METHODS: Twelve patients with ischaemic heart disease and sustained ventricular tachycardia were treated with dofetilide [500 microg twice daily (b.i.d.)] or sotalol (160 mg b.i.d., randomised sequence separated by ...
Grosse-Meininghaus D - - 2002
The implantable defibrillator (ICD) is an established therapy in the prevention of sudden cardiac death by defibrillation of ventricular fibrillation. Another specific feature of the ICDs is antitachycardia pacing (ATP) of ventricular tachycardia. Several studies report success rates of ATP in 83 to 98% of cases. In clinical practice the ...
Della Bella P - - 2002
AIMS: The role of a novel non-contact mapping system (ESI 3000, Endocardial Solutions) to guide radiofrequency catheter ablation of untolerated ventricular tachycardia was investigated in 17 patients; 11 with prior myocardial infarction, three with arrhythmogenic right ventricular dysplasia, and three with idiopathic dilated cardiomyopathy. METHODS: Twenty-seven monomorphic ventricular tachycardias were ...
Napolitano Carlo - - 2002
Pathogenesis of familial inherited arrhythmias is being progressively clarified thanks to the insights provided by molecular biology and by functional studies. Transmembrane or intracellular ion channel mutations have been identified in genetically determined forms of polymorphic ventricular tachycardia and sudden death such as catecholaminergic ventricular tachycardia, long QT syndrome, and ...
Papadatos G Alex - - 2002
Voltage-gated sodium channels drive the initial depolarization phase of the cardiac action potential and therefore critically determine conduction of excitation through the heart. In patients, deletions or loss-of-function mutations of the cardiac sodium channel gene, SCN5A, have been associated with a wide range of arrhythmias including bradycardia (heart rate slowing), ...
Glikson Michael - - 2002
INTRODUCTION: Rate smoothing is an algorithm initially designed to prevent rapid changes in pacemaker rates. In this study, we sought to determine the potential of the rate-smoothing mechanism in preventing detection of ventricular tachyarrhythmias. METHODS AND RESULTS: Clinical testing of rate smoothing was performed at the time of defibrillator arrhythmia ...
Shah Dipen C - - 2002
Superior Vena Cava Reentry. High-resolution mapping of a tachycardia originating from the superior vena cava (SVC) in a patient with atrial fibrillation is described. Unidirectional circuitous repetitive activation encompassing the full tachycardia cycle length was documented around a line of block within the myocardial sleeve of the SVC. Intermittent conduction ...
Durham D - - 2002
OBJECTIVE: To review the diagnosis and management of cardiac arrhythmias in a two-part presentation. DATA SOURCES: Articles and published peer-review abstracts on tachycardias and bradycardias. SUMMARY OF REVIEW: Normal cardiac rhythm originates from impulses generated within the sinus node. These impulses are conducted to the atrioventricular node where they are ...
Mela Theofanie - - 2002
A young ICD recipient with a history of syncope and idiopathic polymorphic ventricular tachycardia/ventricular fibrillation presented after an ICD discharge. She had delivered her first child 8 days prior to the event and she had been lactating. Numerous short runs of polymorphic ventricular tachycardia/ventricular fibrillation resolved with aggressive replacement of ...
Tan C S - - 2002
INTRODUCTION: Incessant ventricular tachycardia is a rare arrhythmia which can be life threatening. Treatment with anti-arrhythmic agents may occasionally fail. CLINICAL PICTURE: We report 2 cases of incessant ventricular tachycardia. The first case was a young man with idiopathic left ventricular tachycardia who was in incessant ventricular tachycardia despite treatment ...
Manita M - - 2002
We present a case with two forms of atrioventricular nodal re-entrant tachycardia (AVNRT) that revealed similar H-A-V sequences, but could be differentiated only by their retrograde atrial activation sequences. Both tachycardias were induced following anterograde slow pathway conduction, suggesting the slow pathway as the anterograde limb of the re-entry circuit. ...
van Dessel Pascal F - - 2002
This article investigates the influence of body surface mapping on outcome of ventricular antiarrhythmic surgery. Preoperative mapping is advocated to optimize map-guided antiarrhythmic surgery of postinfarction ventricular tachycardia. We sequentially analyzed the results of catheter activation sequence mapping, body surface mapping, and intraoperative multielectrode mapping in 54 patients and made ...
Martínez-Rubio A - - 2002
OBJECTIVE: The aim of this prospective study was to analyze the yield of early vs late introduction of a third extra-stimulus during programmed ventricular stimulation. METHODS: Two randomized protocols of programmed ventricular stimulation were used in 94 consecutive patients with coronary artery disease who were studied because of non-sustained ventricular ...
Sadoul Nicolas - - 2002
INTRODUCTION: Despite technologic developments, accurate discrimination of ventricular tachyarrhythmia from rapid rhythms of nonventricular origin remains a challenge. We sought to examine the sensitivity and specificity of a dual-chamber arrhythmia detection algorithm, the PARAD algorithm, incorporated in a dual-chamber implantable cardioverter defibrillator, the Defender (ELA Medical). METHODS AND RESULTS: All ...
Nelson Lewis S - - 2002
Drug-induced polymorphic ventricular tachycardia (torsades de pointes) may lead to syncope or sudden cardiac death. One mechanism by which drugs and toxins may predispose to the development of this malignant dysrhythmia is through their ability to produce myocardial sensitization. The concept of myocardial sensitization actually represents a series of events ...
Davidson Neil C - - 2002
The term "Mahaim fiber" usually is applied to an atriofascicular fiber that inserts distally into the right bundle branch and forms the anterograde limb of a reciprocating tachycardia. One of the features that has been used to describe the physiology of Mahaim fibers is the presence of anterograde preexcitation. We ...
Gamssari Farhad - - 2002
A 92-year-old woman with normal systolic function had recently begun using the newly approved phosphodiesterase III inhibitor cilostazol when she was admitted with lower-extremity pain. Cilostazol is indicated for patients with intermittent claudication and contraindicated for patients with congestive heart failure. Two days after admission, the patient developed ventricular tachycardia. ...
Kuo J Y - - 2001
INTRODUCTION: Coexistence of double tachycardias in one patient has been infrequently reported. Furthermore, the mechanisms of transition between double paroxysmal supraventricular tachycardias have not been well studied. METHODS AND RESULTS: Thirty-five patients with two paroxysmal supraventricular tachycardias were studied. Group IA consisted of 3 patients with spontaneous transition between AV ...
Moak J P - - 2001
Atriofascicular pathways most commonly present electrocardiographically as an antidromic reciprocating AV reentrant tachycardia. We report the case of a child who presented in infancy with a wide QRS complex tachycardia thought to be supraventricular tachycardia with aberrant conduction, associated with tachycardia-induced cardiomyopathy. Later in life the same patient represented with ...
Pérez-Castellano N - - 2001
An 18-year-old woman presented with recurrent exercise-induced syncopal episodes and severe systolic dysfunction. ECG monitoring disclosed repetitive polymorphic ventricular complexes, paroxysms of bidirectional ventricular tachycardia, and nonsustained bursts of slow polymorphic ventricular tachycardia that increased in length and rate during exercise. Ventricular arrhythmias were refractory to medical treatment, which included ...
Ciaccio E J - - 2001
BACKGROUND: Knowledge of the pathway common to both wave fronts in figure-8 reentrant circuits (ie, the isthmus) is of importance for catheter ablation to stop reentrant ventricular tachycardia. It was hypothesized that quantitative measures of reentry isthmus geometry were interrelated and could be correlated with tachycardia cycle length. METHODS AND ...
Di Donato M - - 2001
Surgical ventricular reconstruction (SVR) involves resection of scar, septal exclusion, cavity reduction by endoventricular patch, and complete coronary grafting. At the Cardiothoracic Centre of Monaco, ventricular stimulation (PVS) is performed before SVR, unless contraindicated. In patients with spontaneous and/or inducible ventricular arrhythmias, nonguided endocardiectomy and cryosurgery are added. We report ...
Tritto M - - 2001
A case of iterative atrial tachycardia leading to dilated cardiomyopathy is reported. During electrophysiologic study, the tachycardia showed a markedly irregular cycle length associated with changes in atrial activation breakthrough as demonstrated by coronary sinus (CS) recordings and frequently degenerated into self-terminating atrial fibrillation. Left atrial transseptal mapping demonstrated the ...
Balaji Seshadri - - 2001
The cardiac rhythm can be very labile in the early postoperative period, necessitating a high degree of vigilance. Bradycardia may be due to sinus node dysfunction or varying degrees of atrioventricular block, both of which are usually due to surgical trauma. Temporary pacing, using implanted temporary pacing wires, should be ...
Hanisch D - - 2001
During the past decade, our awareness and understanding of arrhythmias in children has expanded immensely. This report discusses the more commonly encountered pediatric rhythm disturbances, including sinus node dysfunction, the various forms of supraventricular tachycardia, ventricular tachycardia, long QT syndrome, and the atrioventricular blocks. The electrocardiographic characteristics, electrophysiological mechanisms, clinical ...
Schmitt H - - 2001
INTRODUCTION: Azimilide blocks the slow (I(Ks)) and fast (I(Kr)) components of the delayed rectifier potassium channel. It also has blocking effects on sodium (I(Na)) and calcium currents (I(CaL)). Its effects on reentrant circuits in infarct border zones causing ventricular tachyarrhythmias are unknown. METHODS AND RESULTS: Activation in reentrant circuits causing ...
Haynes B E - - 2001
Two patients in the prehospital setting died immediately after receiving adenosine for presumed supraventricular tachycardia. Both patients' cardiac rhythms were atrial fibrillation rather than supraventricular tachycardia, and their unstable conditions resulted from underlying diseases-chronic obstructive pulmonary disease and pulmonary embolism-rather than the tachycardia. Misinterpretation of the cause of tachycardia as ...
Van Zijl D H - - 2001
A woman of 40 weeks' gestation, who was apparently previously healthy, required emergency caesarean section after a failed vacuum delivery. While under spinal anaesthesia she developed a supraventricular tachycardia of unknown origin. Intravenous verapamil resulted in a conversion to sinus rhythm. Further investigations confirmed Wolff-Parkinson-White syndrome, for which she required ...
Pierce W J - - 2001
Multifocal atrial tachycardia is an electrocardiographic phenomenon seen primarily in the elderly. The hemodynamic consequences of multifocal atrial tachycardia in an elderly woman are presented. Successful treatment with Ibutilide is demonstrated. Treatment with a class III antiarrhythmic agent opposes the frequently accepted mechanism of triggered activity in causing this arrhythmia.
Saoudi N - - 2001
Regular atrial tachycardias classically are classified into flutter or tachycardia, depending on the rate and presence of a stable baseline on the ECG. However, current understanding of electrophysiology atrial tachycardias makes this classification obsolete, because it does not correlate with mechanisms. The proposed classification is based on electrophysiologic mechanisms, defined ...
Volpi A - - 2001
BACKGROUND: There is little epidemiologic information from large multicenter databases on sustained monomorphic ventricular tachycardia occurring after the initial 48 hours of myocardial infarction. METHODS: We reassessed its incidence and short-term prognosis in 16,842 patients with a definite myocardial infarction enrolled in the Gruppo Italiano per lo Studio della Soprovvivenza ...
Calò L - - 2001
The present case report describes the diagnosis of a concealed bypass tract in the right lateral wall revealed by electrophysiologic evaluation performed in a patient with rare palpitations. A iatrogenic right bundle branch block (RBBB) caused the occurrence of an incessant atrioventricular reentrant tachycardia. The disappearance of the RBBB determined ...
Schmitt H - - 2001
INTRODUCTION: Spontaneous changes in QRS morphology during sustained reentrant ventricular tachycardia, occurring gradually or abruptly, causing the tachycardia to be polymorphic, have been described in clinical cases. The purpose of this study was to determine the mechanism for such changes in a canine infarct model. METHODS AND RESULTS: Reentrant circuits ...
Eckardt L - - 2001
INTRODUCTION: The Brugada syndrome is a distinct form of idiopathic ventricular fibrillation characterized by a unique ECG pattern consisting of a right bundle branch block-like aspect and ST segment elevation in leads V1 to V3. As a high induction rate of ventricular tachyarrhythmias has been reported in Brugada syndrome, we ...
Samniah N - - 2001
We report a case of an 85-year-old patient with posturally-induced syncope in whom symptoms were reproduced during tilt table testing in conjunction with development of an accelerated junctional rhythm with isorhythmic atrio-ventricular (AV) dissociation. That loss of AV synchrony was crucial to development of hypotension and syncope was demonstrated during ...
Therrien J - - 2001
BACKGROUND: Chronic pulmonary regurgitation after repair of tetralogy of Fallot (TOF) may lead to right ventricular dilatation, which may be accompanied by ventricular tachycardia and sudden death. We aimed to examine the effects of pulmonary valve replacement (PVR) on (1) certain electrocardiographic markers predictive of monomorphic ventricular arrhythmia and sudden ...
Sticherling C - - 2001
INTRODUCTION: The purpose of this prospective study was to determine the prevalence and clinical significance of inducible atrial tachycardia in patients undergoing slow pathway ablation for AV nodal reentrant tachycardia who did not have clinically documented episodes of atrial tachycardia. METHODS AND RESULTS: Twenty-seven (15%) of 176 consecutive patients who ...
Kinoshita S - - 2001
Electrocardiography was performed in a newborn boy without organic heart disease, in whom supraventricular extrasystoles with varying coupling were seen. The supraventricular extrasystoles were occasionally followed by ventricular extrasystoles. The coupling intervals of ventricular extrasystoles to the preceding supraventricular extrasystoles were also considerably variable. Ventricular tachycardia occurred following comparatively late ...
Knight B P - - 2001
BACKGROUND: Patients who are misdiagnosed with ventricular tachycardia because of electrocardiographic artifact may be subjected to unnecessary procedures. The purpose of this study was to determine how often electrocardiographic artifact is misdiagnosed as ventricular tachycardia. METHODS: Physicians (n = 766) were surveyed with a case simulation that included a two-lead ...
Guo H - - 2001
INTRODUCTION: Tachycardia with a QRS configuration which resembles that in sinus rhythm is usually thought to be supraventricular. Ventricular tachycardia, with a similar QRS configuration to that in sinus rhythm on the 12-lead ECG, can occur. The mechanisms of this form of ventricular tachycardia have not been previously reported. METHODS ...
Bakker P F - - 2001
OBJECTIVE: Surgery for ventricular tachycardias late after myocardial infarction is frequently associated with high mortality including sudden death, and arrhythmia recurrences. We examined our results of sequential map-guided endocardial resection at normothermia in patients with ventricular tachyarrhythmias late after myocardial infarction to assess the efficacy of this technique as well ...
Gupta A K - - 2001
Wide QRS complex tachycardia is a common clinical occurrence and presents a diagnostic challenge for the physician. History, physical examination, chest radiographs, and electrocardiographic analysis are important in making the correct diagnosis. Diagnosis of ventricular tachycardia is supported by history of prior myocardial infarction or congestive heart failure, physical examination ...
Villazon E - - 2001
The congenital form of junctional ectopic tachycardia has never been reported during the prenatal period. We describe a case in which the diagnosis could be ascertained in utero with the superior vena cava/ascending aorta Doppler approach. The diagnosis was based on the evidence of ventricular tachycardia with atrioventricular (AV) dissociation ...
Fernández del Palacio M J - - 2001
A seven-month-old male Siberian husky was presented with a recent history of anorexia, hindlimb weakness and syncope. Physical examination revealed severe tachycardia, tachypnoea and dyspnoea. Mucous membranes were pale and femoral pulses were weak. An electrocardiogram showed sustained ventricular tachycardia with a left bundle branch block configuration. Thoracic radiographs revealed ...
Parham W A - - 2001
Adenosine is frequently used in emergency departments and intensive care units for the termination of narrow complex tachycardias. Recently its utility in terminating wide complex tachycardias has been reported in the literature. Adenosine is generally felt to be a safe medication even though its proarrhythmic effects in the setting of ...
Weigner M J - - 2001
The patient with nonsustained ventricular tachycardia represents a common management problem for the cardiologists and internists. Treatment is sometimes needed for the suppression of symptoms. More commonly, nonsustained ventricular tachycardia is asymptomatic, and the clinician must determine the prognostic importance. The prognostic implications, the role of electrophysiologic study, and the ...
Hanna M S - - 2001
BACKGROUND: Resetting has been used to characterize reentrant circuits causing clinical tachycardias. METHODS AND RESULTS: To determine the mechanisms of resetting, sustained ventricular tachycardia was induced in dogs with 4-day-old myocardial infarctions by programmed stimulation. Premature stimulation was accomplished from multiple regions within reentrant circuits; resetting curves were constructed and ...
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