190: In how many patients with Wolff-Parkinson-White syndrome-related adverse presentation isoproterenol infusion was required to reproduce the arrhythmia?

Electrophysiological study is the main method for the detection of patients with a Wolff-Parkinson-White syndrome (WPW) at risk of adverse presentation (resuscitated ventricular fibrillation (VF), documented life-threatening arrhythmia): the protocol is debated. The purpose of the study was to look in how many patients with WPW-related adverse presentation, atrial fibrillation (AF) or atrial tachycardia with the shortest RR cycle length (CL) with 1/1 conduction over accessory pathway (AP)<250msec was induced in control state (CS) and when isoproterenol was required.Methods63 patients, mean age 38±18, were referred for WPW-related adverse presentation (VF 6, other 56). EPS included in CS atrial pacing and measurement of the shortest CL with 1/1 conduction over AP and programmed stimulation with 1 and 2 extrastimuli. AP effective refractory period (ERP) was determined. In absence of induction of a tachycardia with a CL <250msec, isoproterenol (0.02 to 1μg. min-1) was infused to increase sinus rate to 130bpm; the protocol was repeated.ResultsMean shortest CL conducted over AP was 223±30msec in CS, 192±25msec after isoproterenol. APERP was 225±29msec in CS, 191±19msec after isoproterenol. Atrioventricular orthodromic tachycardia (AVRT) was induced in 34 patients (54%), antidromic tachycardia (ATD) in 13 (21%), AF in 43 (68%). Criteria for a malignant form (induction of AF or ATD with a shortest CL <250mesc) were noted in 42 patients (67%) in CS and were obtained after isoproterenol in remaining 21 patients (33%). Among these patients, 12 had inducible tachycardia in CS (AVRT (n=6), ATD (n=3), AF (n=3) but the shortest CL was >240msec. A tachycardia was only induced after isoproterenol in 9 patients (14%).ConclusionsInfusion of isoproterenol should be systematic when WPW is evaluated. EPS performed only in CS missed at least 14% of patients at risk of life-threatening arrhythmias who had no inducible supraventricular tachyarrhythmia and 33% of patients with a WPW without the classical criteria for a malignant form. Isoproterenol increased the sensitivity of EPS for the detection of malignant form from 67 to 100%

092: Prognosis value of QRS duration in patients with heart disease and syncope

BackgroundPatients with heart disease (HD) and syncope are at high risk of sudden death. Implantable defibrillator (ICD) is recommended in patients with unexplained syncope and left ventricular ejection fraction (LVEF) < 30% or in patients with LVEF >30% and inducible ventricular tachycardia (VT).AimThe purpose of the study was to evaluate the prognostic significance of QRS duration measurement in patients with HD and syncope.Methods528 patients, 89 women and 439 men, mean age 65±12 years, were admitted for syncope. All of them had an HD, either ischemic HD (n=382) or left ventricular impairment of other origin (n=115). Holter monitoring, electrophysiological study and head-up tilt test were systematic. Filtered QRS duration was measured at signal-averaged ECG (Fidelity 2000 of Cardionics) (filter 40 Hz, noise level < 0.6 μV). The patients were followed from 3 months up to 18 years (mean 5 ±4 years).ResultsMean LVEF was 40±14%. Cardiac defibrillator was implanted in 73 patients. 30 patients died suddenly, 75 died from heart failure or were transplanted (n=9). Remaining patients are alive or died from non cardiac death (n= 8). The last group differed from group who died suddenly by an higher LVEF (42±14% vs 32±13) (p< 0.00001) and a shorter QRS duration (125±34 msec vs 144±31) (p< 0.026). They tended to be older (65±12 years vs 61±13) (p<0.09). The alive group differed also from group who died from heart failure by an higher LVEF (42±14% vs 33±13) (p< 0.001) and a shorter QRS duration (125±34 msec vs 141±31) (p< 0.0033). They tended to be younger (65±12 years vs 67±10) (p<0.08). Patients who died suddenly and those who died from heart failure had similar LVEF and QRS duration but patients who died suddenly are younger than patients who died from heart failure (p<0.01).ConclusionsLow LVEF is a classical risk of worse prognosis in patients with HD and syncope. A longer QRS duration is also a noninvasive and simple test of worse prognosis. A QRS duration more than 125 msec had a sensitivity of 73% and a specificity of 64% to predict cardiac mortality

Le défibrillateur automatique implantable en prévention primaire dans la cardiopathie ischémique et dilatée (à propos de 252 patients consécutifs implantés au CHU de Nancy)

La mort subite cardiaque constitue un véritable problème de santé publique. Près de 30 ans après la première implantation de défibrillateur automatique implantable (DAI), la supériorité de ce dispositif par rapport au traitement médicamenteux en prévention primaire de la mortalité liée aux troubles du rythme d'origine ventriculaire est désormais bien établie. Cependant la pose et le suivi d'un DAI sont marqués par la survenue d'un certain nombre de complications potentielles. Dans notre étude rétrospective, nous nous sommes intéressés à 252 patients implantés d'un DAI en prévention primaire sur une cardiopathie ischémique ou dilatée dans le service de Cardiologie du CHU de Nancy, de juillet 1999 à décembre 2007 avec une durée de suivi de 23,1 * 20,9 mois. Le sexe, l'âge, la cardiopathie sous jacente, la localisation de l'infarctus n'apparaissent pas comme des facteurs prédictifs de décès. Par contre, la population en attente de greffe et la population décédée ont présentés significativement plus de troubles du rythme ventriculaires rapides. Près de 30% de la population a présenté des traitements appropriés avec a contrario plus de 11% de traitements inappropriés et au total 23% de complications de tout ordre liés au DAI. Ainsi 15% des patients ont eu des complications sans avoir bénéficié du DAI au cours du suivi. Ces résultats posent le problème de la détection de la population cible afin d'améliorer le rapport bénéfice / risque du DAI en prophylaxie primaire.NANCY1-SCD Medecine (545472101) / SudocNANCY1-Bib. numérique (543959902) / SudocSudocFranceF

Is Ablation of Atrial Flutter Always Safe?

International audienceBackground: Radiofrequency ablation of typical atrial flutter is largely used and is considered as safe. The purpose of the study was to evaluate the prevalence and the causes of severe adverse event (AE) following atrial flutter ablation.Methods: Ablation of typical flutter was performed by conventional method with an 8-mm-tip electrode catheter, a maximum power of 70 W, and a maximum target temperature of 70° for 60 seconds in 883 patients, (685 males and 198 females aged from 18 to 93 years [64 ± 11.5]; 664 had heart disease [HD]).Results: AE occurred in 44 patients (5%). AE was life threatening in 14 patients: poorly tolerated bradycardia (transient complete atrioventricular block [AVB] or sinus bradycardia [SB] <40 beats per minute) associated with cardiac shock and acute renal failure in five patients, tamponade (n = 1), bleeding leading to death (n = 1), various AE-related deaths (n = 2), ventricular tachycardia-related death (n = 1), definitive complete AVB (n = 3), and right coronary artery occlusion-related complete AVB (n = 1). Less serious AE occurred in 30 patients: transitory major SB or second- or third-degree AVB (n = 23), bleeding (n = 4), transient ischemic attack (n = 1), and various AE (n = 2). Most of the bradycardia was related to β-blockers or other antiarrhythmic drugs used to slow atrial flutter. Factors of AE were female gender (36% vs 22%, P < 0.02) and the presence of ischemic (P < 0.03) or valvular HD (P < 0.01).Conclusions: AE following atrial flutter ablation occurred in 5% of patients. Most of them are avoidable by control of anticoagulants and arrest of rate-control drugs used to slow the rate of atrial flutter

180 Is it a risk of stroke in Wolff Parkinson White syndrome?

Atrial fibrillation (AF) is a major cause of stroke. AF incidence is increased in Wolff-Parkinson-White syndrome (WPW), represents about 10% of spontaneous arrhythmias and has several mechanisms as the degeneration of atrioventricular reentrant tachycardia (AVRT) into AF, the AF facilitation by the atrial insertion of accessory pathway (AP) or another origin. The purpose of study was to assess the incidence of stroke in patients (pts) who had a preexcitation syndrome.Population707 pts aged from 5 to 85 years (mean 34.5±17) were studied for a WPW: 93 pts had unexplained syncope; 247 pts were asymptomatic; 367 pts had spontaneous tachycardias; among these pts 52 had documented AF. Electrophysiological study (EPS) consisted of atrial pacing and programmed atrial stimulation in control state and if necessary after infusion of isoproterenol. Clinical and electrophysiological data were collected.ResultsStroke was noted in 5 pts (0.7%), 2 women, 3 men aged from 53 to 75 years. They had a normal carotid and transcranial Doppler ultrasonography. One pt had ischemic heart disease and the remaining pts had no heart disease. Their age was significantly older than remaining population (62±9 years vs 34±17) (p<0.0002). Only one pt had spontaneous AF; 51 other pts with spontaneous AF had no stroke. One of 247 was asymptomatic; one pt of 93 had syncope and 2 pts of 315 had spontaneous AVRT. At EPS, one asymptomatic pt had AP with long refractory period and no inducible tachycardia. Two pts with spontaneous tachycardias had only inducible AVRT and the pt with spontaneous AF had inducible antidromic tachycardia and AF. The pt with syncope had only inducible AF. These electrophysiological data did not differ from the remaining population. Anticoagulants were maintained after AP ablation, although the disappearance of arrhythymias.ConclusionsThe risk of stroke in WPW syndrome is very low (0.7%). Only one clinical factor differs significantly from remaining population, the relatively old age (mean 62±9 years). All other clinical factors as sex, associated heart disease, spontaneous symptoms and all electrophysiological data did not differ from remaining population