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S Lévy

Publications and source records attributed to S Lévy.

At least 19 recordsLinked to original sources
PubMed2006

Late lethal hepatitis B virus reactivation after rituximab treatment of low-grade cutaneous B-cell lymphoma.

The chimeric anti-CD20 monoclonal antibody, rituximab, is a promising treatment for cutaneous B-cell lymphomas. Classically used in combination with a multiagent-chemotherapy regimen, it can sometimes give excellent results alone. Because of its selective action on B lymphocytes, it is considered a moderate immunosuppressant in terms of infection. We describe a woman with relapsed cutaneous follicular centre B-cell lymphoma and secondary lymph-node involvement treated with rituximab alone, which induced a complete remission. One year later, she experienced a fatal hepatitis B virus (HBV) reactivation. Several such HBV reactivations were reported after combined rituximab and multiagent chemotherapy for B-cell lymphomas. This is the first case of HBV reactivation occurring during the year following rituximab monotherapy in the absence of any other immunosuppressive factor.

Aged↗
PubMed2005

[Remodelling in atrial fibrillation].

It is well known that atrial fibrillation (AF) tends to become permanent with time as illustrated by the fact that it becomes more difficult to maintain sinus rhythm when AF has been present for a long time. Atrial remodelling plays a part in this process and has been studied in experimental models. Atrial remodelling is defined as all the phenomena occurring during AF contributing to its maintenance. The persistence of AF induced by stimulation in the animal depends on the duration and the repetition of the atrial stimulation and it would appear that "AF induces AF". The tendency for AF to persist is associated with a shortening of the effective atrial refractory period with loss of its adaptation to the heart rate. The determining factor of both electrical and structural remodelling is the rapidity of the atrial rhythm of the AF itself. These phenomena lead to a type L calcium cellular overload as shown by its prevention or attenuation by the administration of verapamil, a calcium antagonist. Electrical remodelling is accompanied by a structural remodelling in the experimental model of persistent AF over several weeks. Samples from the two atria examined by electronic microscopy show mitochondrial changes, an accumulation of glycogen, a deficit in myofibrils, a redistribution of the nuclear chromatim and a reduction of sarcoplasmic reticulum with changes in protein structure. This structural remodelling is a reaction of adaptation similar to that observed in hibernating myocardium during ischaemia and aims to prolong cellular viability by decreasing atrial contractility. Another aspect of structural remodelling is the activation of fibroblasts with formation of fibrosis with resulting heterogeneity of the conduction tissue. There is also an increase in converting enzyme and angiotensin II concentrations. Irbesartan, an angiotensin II antagonist, reduced fibroblast growth. This has clinical applications as shown by the reduction in the recurrences of AF after cardioversion when given in association with amiodarone. Persistent AF leads to left atrial dilatation with abnormal atrial contractility. Further studies are necessary to determine the effect of atrial remodelling which might also act on the foci responsible for inducing the AF. Better understanding of atrial remodelling will contribute to the use of new pharmacological agents to prevent AF.

Atrial Fibrillation↗
PubMed2004

[A multicentre trial of the diagnostic value and cost of electrocardiography in symptoms suggesting arrhythmia with a new event recorder with transtelephonic transmission].

Events recorders are used for electrocardiographic documentation of symptoms of arrhythmia too sporadic and short lasting to be recorded by 24 hour Holter monitoring. However, there are no French studies comparing the value and cost of event recorders with conventional diagnostic methods. Recently, a new telediagnostic device has become available in France leading to an assessment of the technique. The aim of this study was to determine the value of this event recorder and the cost of diagnostic ECG in the assessment of presumed arrhythmic symptoms such as palpitations or rare tachycardia (<3 episodes per week) of short duration, compared with conventional techniques. Fifty-eight patients with these criteria were randomised, 30 to Survcard (Group I) and 28 to conventional diagnostic methods (Group II). The patients were comparable with respect to age, sex distribution, type of symptoms and associated cardiac disease. The ECG diagnosis of the symptoms was established in 20 cases (66.6%) of patients in Group I in 17 +/- 16 days, and in 14 cases (50.0%) of Group II in 23 +/- 28 days. The difference between the two groups was not statistically significant. The cost of a positive diagnosis for Group I (Survcard) varied from 0 to 228.47 Euro with an average of 71.22 +/- 117.02 Euro. The cost of positive diagnosis in Group II varied from 76.80 to 2340.41 Euro with an average of 480.39 +/- 797.41 Euro. In conclusion, this study showed that the percentage of patients with a positive diagnosis was comparable in the two groups but that the cost was 6 times higher in the group investigated by conventional methods than in the Survcard group because of more costly medical intervention.

Arrhythmias, Cardiac↗
PubMed2002

Catheter ablation using very high frequency current: effects on the atrioventricular junction and ventricular myocardium in sheep.

BACKGROUND: Radiofrequency ablation is currently used in the treatment of various cardiac arrhythmias. However, this technique is limited by impedance rise, leading to coagulum formation and desiccation of tissue. We developed a new generator, providing very high frequency (27 MHz) current, which is in the intermediate range between radiofrequency and microwave energy. The aim of this study was to evaluate the results for catheter ablation of the atrioventricular junction and characteristics of the lesions obtained at ventricular sites. METHODS AND RESULTS: The generator was coupled to a specially designed 7-French coaxial catheter. The study included experiments performed on 10 sheep (Wt. 31- 42 kg). In seven sheep, the catheter was introduced into the femoral vein and advanced across the tricuspid annulus to record the largest possible His electrogram. VHF current was applied for 25 s, with increasing energies. The energy needed to obtain complete atrioventricular (AV) block ranged from 60 to 100 Watts. Six animals were observed for 6 to 21 days. Complete AV block was found to be persistent. In those seven sheep in whom AV junction was ablated and in three additional sheep, the ablation catheter was positioned toward the right ventricular apex using the same approach and into the left ventricle via the femoral artery, and 20 to 90 Watts energy was delivered in order to assess the size of the induced lesions. Side effects included ventricular tachycardia degenerating into ventricular fibrillation in six cases, but the same effect was observed in this animal model with radiofrequency energy. No cardiac perforation was noted. No thrombus was observed at the catheter tip. The size of the lesion ranged from 3 to 45 mm in width and 1 to 15 mm in depth. CONCLUSIONS: Catheter ablation using VHF current is feasible and appears effective in producing stable AV block when applied at the AV junction and results in substantial myocardial lesions. Further studies are needed to define its clinical interest and side effects.

Animals↗
PubMed2002

[Cardioversion by external electric shock for atrial fibrillation: does patient age affect immediate results?].

The restoration of sinus rhythm by external electric shock in patients with persistent atrial fibrillation is a well established treatment. However, in current practice this treatment is generally indicated less in the elderly subject although this attitude is not factual. The objective of this work was to evaluate the immediate results of cardioversion by external electric shock, comparing the success rates in four age groups: under 60 years, between 60 and 69 years, between 70 and 79 years, and over 80 years. This study was performed on 182 consecutive patients aged from 25 to 89 years: 35 patients aged less than 60 years, 52 patients aged from 60 to 69 years, 65 patients aged from 70 to 79 years, and 30 patients aged 80 years or over. The success rates were 91.4% before 60 years, 90.4% between 60 and 69 years, 90.8% between 70 and 79 years, and 83.3% after 80 years. There was no significant difference between the success rates in the four age groups (p = 0.68). Among the other factors analysed, only the duration of atrial fibrillation and the body mass index significantly influenced the results of external electric shock in this series. This work suggests that age does not significantly influence the immediate results of external electric shock. According to these data it does not appear justified to contra-indicate cardioversion by external electric shock on the sole criterion of age.

Adult↗
PubMed2001

ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation: Executive Summary A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients With Atrial Fibrillation) Developed in Collaboration With the North American Society of Pacing and Electrophysiology.

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Aged↗
PubMed2001

Inducible ventricular arrhythmias and patency of infarct-related artery in survivors of acute myocardial infarction.

BACKGROUND: Patency of infarct-related artery in patients who suffered an acute myocardial infarction (AMI) has been shown to be associated with improved survival. Ventricular tachyarrhythmias induced by programmed electrical stimulation may be predictive of arrhythmic events and sudden death. HYPOTHESIS: The study was undertaken to assess the possible effect of a patent infarct-related coronary artery on induced ventricular tachyarrhythmias during programmed ventricular stimulation in survivors of AMI. METHODS: In this prospective study, programmed electrical stimulation was performed before hospital discharge (14 +/- 2 days) in 79 patients who survived an AMI. Patients were subdivided into two groups: Group I with patent infarct-related coronary artery (n = 64) and Group 2 with occluded infarct-related artery (n = 15) at coronary angiography performed at 14 +/- 2 days. These two groups were comparable in terms of mean left ventricular ejection fraction, location of infarct-related artery, number of diseased vessels, peak creatine kinase value, and infarct location. RESULTS: Ventricular arrhythmias were induced in 21 patients ( 32.6%) of Group I and 4 patients (26.6%) of Group 2. This difference was not statistically significant. CONCLUSION: This study suggests that ventricular arrhythmias induced by programmed ventricular stimulation in survivors of AMI did not differ whether the infarct-related artery was patent or occluded. Other factors may play a role in electrical instability as assessed by programmed ventricular stimulation.

Arrhythmias, Cardiac↗
PubMed2001

ACC/AHA/ESC guidelines for the management of patients with atrial fibrillation: executive summary. A Report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients With Atrial Fibrillation): developed in Collaboration With the North American Society of Pacing and Electrophysiology.

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Algorithms↗
PubMed2001

Influence of residual myocardial ischaemia on induced ventricular arrhythmias following a first acute myocardial infarction.

OBJECTIVES: The purpose of this study was to assess the possible effect of residual myocardial ischaemia on induced ventricular arrhythmia during programmed ventricular stimulation in survivors of a first acute myocardial infarction. BACKGROUND: Most deaths after hospital discharge for acute myocardial infarction are sudden and presumably arrhythmic. Sudden cardiac death results from a dynamic interaction of structural abnormalities and transient triggering factors. The role of myocardial ischaemia as a trigger for ventricular arrhythmias remains unclear. We hypothesized that residual myocardial ischaemia after a first acute myocardial infarction is a potent trigger for sustained ventricular tachyarrhythmias, particularly in the presence of an abnormal myocardium. METHODS AND RESULTS: In this prospective study, programmed electrical stimulation, coronary angiography and dipyridamole-thallium-201 scintigraphy single-photon emission computed tomography were performed in 90 consecutive survivors of a first acute myocardial infarction. Patients, divided in two groups - group 1 with induced ventricular tachyarrhythmia (n=24) and group 2 without induced ventricular tachyarrhythmia (n=66) - were compared regarding residual myocardial ischaemia. The two groups were comparable in terms of mean left ventricular ejection fraction, infarct size and location, gender ratio, peak creatine kinase value, and extent of coronary disease. Residual myocardial ischaemia was detected in 32 patients: 15 (42.5%) belonged to group 1 and 17 (25.7%) to group 2. There was a statistically significant difference between the two groups regarding the presence and the extent of residual myocardial ischaemia (P<0.05). CONCLUSION: Residual myocardial ischaemia, revealed by dipyridamole-thallium-201 scintigraphy following a first acute myocardial infarction, might contribute to electrical instability evaluated by programmed ventricular stimulation.

Adult↗
PubMed2001

ACC/AHA/ESC guidelines for the management of patients with atrial fibrillation. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to develop guidelines for the management of patients with atrial fibrillation) developed in collaboration with the North American Society of Pacing and Electrophysiology.

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Atrial Fibrillation↗
PubMed2001

Ventricular tachycardia with QRS configuration similar to that in sinus rhythm and a myocardial origin: differential diagnosis with bundle branch reentry.

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 AND RESULTS: The mechanism of ventricular tachycardia was defined during electrophysiological study in five patients. During sinus rhythm, all patients had a wide QRS complex (>0.12 s) on the 12-lead ECG. The morphology remained grossly unchanged during spontaneous, symptomatic tachycardia. Four of the five patients had coronary artery disease and left ventricular dysfunction. The remaining patient had idiopathic dilated cardiomyopathy. The relationship between the His bundle, deflection, the right bundle branch and the QRS complex was evaluated during tachycardia. Atrial and ventricular pacing, and ventricular activation mapping were performed during tachycardia to define the tachycardia mechanism. The tachycardia induced at electrophysiological testing, which was similar to the clinical tachycardia, was proven to be ventricular tachycardia in each patient. The morphology of ventricular tachycardia was right bundle branch block in two patients and left bundle branch block in three patients. The median tachycardia cycle length was 300 ms (range: 260-480 ms). His bundle activation occurred in a 1:1 relationship with ventricular activation during tachycardia in all patients at least intermittently. The tachycardias were thought initially to be bundle branch reentry tachycardia. With further intervention and continued observation, it became clear that His bundle activation was passive and was not required for the tachycardia to sustain. During tachycardia, His bundle activation appeared to precede the local ventricular activation. Instead, the His bundle was activated slowly from the previous ventricular beat causing a long ventricular-His (VH) interval. This was shown by: (1) activation patterns, (2) response to pacing, (3) intermittent VH dissociation, and (4) termination of ventricular tachycardia. CONCLUSION: A unique form of ventricular tachycardia is described. The QRS complex morphology on the 12-lead ECG during tachycardia was grossly similar to that during sinus rhythm. The His bundle activation was passive and occurred with a long activation time from the ventricle to the His bundle. Although it mimics usual bundle branch reentry, this form of ventricular tachycardia appears to be due to a different mechanism in which the His bundle is not obligatory for the continuation of the reentrant phenomenon.

Adult↗
PubMed2001

External cardioversion of atrial fibrillation: comparison of biphasic vs monophasic waveform shocks.

AIMS: It is well established in transthoracic ventricular defibrillation that biphasic truncated waveform shocks are associated with superior defibrillation efficacy when compared with damped sine wave monophasic waveform shocks. The aim of this study was to explore whether biphasic waveform shocks were superior to monophasic waveform shocks for external cardioversion of atrial fibrillation (AF). METHODS AND RESULTS: Fifty-seven patients in whom cardioversion of AF was indicated were randomized in this prospective study, to transthoracic cardioversion with either monophasic damped sine waveform shocks or biphasic impedance compensating waveform shocks. In the group randomized to monophasic waveform shocks (27 patients), a first shock of 150 J was delivered, followed (if necessary) by a 360 J shock. In the biphasic waveform group (30 patients), the first shock had an energy of 150 J and (if necessary) a second 150 J was delivered. All shocks were delivered in the anterolateral chest pad position. Sinus rhythm was restored in 16 patients (51%) with the first monophasic shock and in 27 patients (86%) with the first biphasic shock. The difference was statistically significant (P=0.02). After the second shock, sinus rhythm was obtained in a total of 24 patients (88%) with monophasic shocks and in 28 patients (93%) with biphasic shocks. No complication was observed in either group and cardiac enzymes (CK, CKmb, troponin I, myoglobin) did not show any significant changes. CONCLUSION: This study suggests that at the same energy level of 150 J, biphasic impedance compensating waveform shocks are superior to monophasic damped sine waveform shocks cardioversion of atrial fibrillation.

Adult↗
PubMed2001

Pharmacologic management of atrial fibrillation: current therapeutic strategies.

BACKGROUND: Atrial fibrillation (AF), the most common form of sustained arrhythmia, is associated with a frightening risk of embolic complications, tachycardia-related ventricular dysfunction, and often disabling symptoms. Pharmacologic therapy is the treatment used most commonly to restore and maintain sinus rhythm, to prevent recurrences, or to control ventricular response rate. METHODS: This article reviews published data on pharmacologic treatment and discusses alternative systems to classify AF and to choose appropriate pharmacologic therapy. RESULTS: AF is either paroxysmal or chronic. Attacks of paroxysmal AF can differ in duration, frequency, and functional tolerance. In the new classification system described, 3 clinical aspects of paroxysmal AF are distinguished on the basis of their implications for therapy. Chronic AF usually occurs in association with clinical conditions that cause atrial distention. The risk of chronic AF is significantly increased by the presence of congestive heart failure or rheumatic heart disease. Mortality rate is greater among patients with chronic AF regardless of the presence of coexisting cardiac disease. The various options available for the treatment of chronic AF include restoration of sinus rhythm or control of ventricular rate. Cardioversion may be accomplished with pharmacologic or electrical treatment. For patients in whom cardioversion is not indicated or who have not responded to this therapy, antiarrhythmic agents used to control ventricular response rate include nondihydropyridine calcium antagonists, digoxin, or beta-blockers. For patients who are successfully cardioverted, sodium channel blockers or potassium channel blockers such as sotalol, amiodarone, or a pure class III agent such as dofetilide, a selective potassium channel blocker, may be used to prevent recurrent AF to maintain normal sinus rhythm. CONCLUSIONS: The ultimate choice of the antiarrhythmic drug will depend on the presence or absence of structural heart disease. An additional concern with chronic AF is the risk of arterial embolization resulting from atrial stasis and the formation of thrombi. In patients with chronic AF the risk of embolic stroke is increased 6-fold. Therefore anticoagulant therapy should be considered in patients at high risk for embolization. Selection of the appropriate treatment should be based on the concepts recently developed by the Sicilian Gambit Group (based on the specific channels blocked by the antiarrhythmic agent) and on clinical experience gained over the years with antiarrhythmic agents. For example, termination of AF is best accomplished with either a sodium channel blocker (class I agent) or a potassium channel blocker (class III agent). In contrast, ventricular response rate is readily controlled by a beta-blocker (propranolol) or a calcium channel blocker (verapamil). Alternatively, antiarrhythmic drug therapy may be chosen based on the Vaughan-Williams classification, which identifies the cellular electrophysiologic effects of the drug.

Adrenergic beta-Antagonists↗
PubMed2001

[Acute intracranial hypertension and anicteric cholestasis revealing Whipple's disease without digestive involvement].

Whipple's disease is a rare infectious disease with potential central nervous system manifestations and a poor prognosis. We report the case of a young woman who presented with acute intracranial hypertension associated with cholestasis which revealed Whipple's disease without digestive involvement. The diagnosis was supported by the presence of PAS-diastase positive hepatic granulomas. A long course of antibiotics resulted in complete remission of the disease without relapse. An acute neurologic syndrome associated with cholestasis should suggest Whipple's disease.

Adolescent↗
PubMed2001

Effects of digoxin on chemoreflex in patients with chronic heart failure.

The effects of digitalis on the baroreflexes in human chronic heart failure have been well studied. Similarly, since it has been recently shown that chemoregulation remains generally effective during cardiac failure, the goal of this study was to evaluate the effects of a chronic administration of digoxin on the chemoreflexes. Hemodynamic and blood gas parameters were assessed in 7 patients with chronic congestive heart failure before and after chronic administration for 10 days of digoxin therapy (0.25 mg daily). In both situations measurements were performed 1/ in baseline conditions at room air and, 2/ after inhalation of pure O2 for 30 min, in order to inhibit the activation of the chemoreflexes. At room air, acute O2 inhalation resulted in a significant decrease in heart rate and cardiac output. After digoxin therapy, comparatively to pre-treatment values, cardiac output, stroke volume and PaO2 were significantly higher while heart rate, systemic resistance and pulmonary wedge pressure were lower. Furthermore, acute O2 inhalation did not modify heart rate or any hemodynamic variables. These results suggest that after digoxin therapy chemoreflex was no more activated in these patients. This effect may be related to the sympatho-inhibitory and to the positive inotropic effects of digoxin: improving hemodynamic and blood gas parameters may result in the inactivation of the reflex.

Aged↗