Increased sensitivity of electrophysiological study by isoproterenol infusion in unexplained syncope.

Unlabelled: The purpose of the study was to evaluate the interests of electrophysiologic study (EPS) after infusion of isoproterenol in patients with syncope and negative EPS in control state.

Methods: 1350 patients were consecutively admitted for syncope and EPS. Patients were included if they had no history of tachycardia, a normal Holter monitoring, a negative EPS in control state.

Electrophysiologic characteristics of atria in patients without heart disease.

Background: The significance of atrial fibrillation or tachycardia (AF) induction remains debatable. Some believe that the presence of heart disease (HD) increases the sensitivity and decreases the specificity of programmed atrial stimulation (PAS). There are few data in patients without HD.

Paradoxical effect of isoprenaline infusion.

Background: Isoprenaline (isoproterenol) is a beta-adrenergic drug, used to increase the heart rate and, during electrophysiological study, to facilitate the induction of supraventricular (SVT) and ventricular tachycardias (VT). Decrease in heart rate during isoprenaline infusion is a rare phenomenon. The purpose of the study was to evaluate the incidence, the possible mechanisms, and the significance of a paradoxical bradycardia induced by isoprenaline infusion.

Significance of inducible ventricular flutter-fibrillation after myocardial infarction.

Aim: The purpose of this study was to determine the factors associated with the induction of ventricular flutter/fibrillation (VFl/VF)and its prognostic significance in post-myocardial infarction.

Methods: Programmed ventricular stimulation was performed after myocardial infarction (MI) for syncope (n = 232) or systematically (n = 755); 230 patients had an induced VFl/VF and were followed during 4 +/- 2 years.

Results: VFl/VF was induced in 49/232 patients (21%) with syncope versus 181/755 asymptomatic patients (24%) (NS) and 94/410 patients (23%) with left ventricular ejection fraction (LVEF) <40% versus 136/577 patients (22.

Differences in mechanisms and outcomes of syncope in patients with coronary disease or idiopathic left ventricular dysfunction as assessed by electrophysiologic testing.

Objectives: This study evaluated the causes of syncope and the significance and differences in left ventricular (LV) dysfunction, coronary disease, and idiopathic dilated cardiomyopathy (DCM).

Background: Risk stratification of and indications for an automated defibrillator could differ according to the cause of LV dysfunction.

Methods: Electrophysiologic study, including atrial and ventricular programmed stimulation, was performed in 119 patients with coronary disease (group I) and 61 patients with DCM (group II) with an left ventricular ejection fraction (LVEF) <40% and syncope.

Utility of transesophageal atrial pacing in the diagnostic evaluation of patients with unexplained syncope associated or not with palpitations.

Background: Noninvasive studies are often negative in patients with syncope, normal surface ECG and without heart disease. The purpose of the study was to determine the diagnostic impact of an esophageal electrophysiological study performed during a consultation.

Methods: A total of 154 patients aged from 16 to 87 years were consecutively recruited for unexplained syncope; they had a normal ECG in sinus rhythm, no documented arrhythmia and no patent heart disease.

Influence of age on atrial fibrillation inducibility.

The prevalence of AF is known to increase in the elderly. Some electrophysiological changes were reported in these patients, but the effects of age on AF inducibility and other electrophysiological signs associated with atrial vulnerability are unknown. The purpose of the study was to evaluate the effects of age on atrial vulnerability and AF induction.

Significance of external cardioversion induced atrial tachyarrhythmias.

External cardioversion is used to stop VT or VF in emergency. Supraventricular tachyarrhythmias are sometimes noted after cardioversion in patients known to be previously in sinus rhythm. The purpose of the study was to evaluate the significance of supraventricular tachyarrhythmias induced by external cardioversion.

Causes and prognosis of cardiac arrest in a population admitted to a general hospital; a diagnostic and therapeutic problem.

Background: The purpose of this study was to determine the causes and the prognosis of consecutive patients resuscitated from cardiac arrest occurring in a general hospital. We assessed 28 females and 94 males (aged 13-82 years) who were resuscitated from cardiac arrest not attributable to acute myocardial infarction. Ventricular fibrillation (VF) was documented in 97.

Postoperative ventricular arrhythmias after cardiac surgery: immediate- and long-term significance.

AF is frequent after cardiac surgery. However, ventricular arrhythmias are less known. The purpose of the study was to evaluate the causes and the prognostic significance of severe ventricular arrhythmias occurring after cardiac surgery.