Evaluation of the patients with syncope during the first month after coronary artery bypass graft

Background: Syncope is a well-known risk factor for adverse cardiovascular event in patients with coronary artery disease, especially those with previous myocardial infarction (MI) or left ventricular dysfunction. The aim of this study was to assess electrophysiologic findings and results of head-up tilt test (HUTT) in patients with syncope and without orthostatic changes in blood pressure during the first month after coronary artery bypass graft (CABG). Materials and Methods: A total of 20 patients with syncope during the first month after CABG were prospectively enrolled in this study from June 2002 to April 2006. Electrophysiologic study (EPS) was performed in all of them. HUTT was performed in all of the patients regardless of the result of EPS. Results: The mean age of patients was 60.311 years. Twelve patients were males. EPS was negative in 18 patients. HUTT was positive in 10 patients. Six patients had old MI. Ischemic insult occurred in one patient after CABG. Left bundle branch was present in two patients. There was a significant relationship between the duration of bed rest after CABG and positive HUTT (P value = 0.021). All of the patients except one did not experience syncope during the follow-up period. Conclusion: In patients with syncope during the first month post CABG, in whom an arrhythmic cause is suspected, the other cause of syncope like orthostatic intolerance should be considered. Being bedridden for an extended period of time post CABG can be a predisposing factor

0049: Long-term follow- up of AV conduction disturbances after slow pathway ablation in patients with AV node reentrant tachycardia

AV block following radiofrequency (RF) ablation for the treatment of atrioventricular nodal reentrant tachycardia (AVNRT) is a rare but well recognised complication of the procedure. The purpose of the study was to report the long-term follow-up of patients a first d (AVB1), second d (AVB2), or third d A V block (AVB3) occurred during ablation of AVNRT.Methods930 patients, 615 females, aged from 12 to 92 years, mean age 52±18, had AVNRT. RF energy, 65°, 40 watts was delivered on the slow pathway, until AVNRT was not induced.Results94 patients presented a transitory or permanent AVB1,2,3. In 8, mean age 53±21.5 years, AVB was of vagal origin generally occurring at femoral puncture (group I). In 26 patients, mean age 46±21, it was traumatic and regressive occurring either in young patients with a normal conduction system or in 3 patients with a left bundle branch block. In remaining 60 patients, AVB was directly related to the RF application; AVB was of first degree in 22 patients aged 56±17 years; it was of 2nd or third degree AVB in 38 patients: in 2 patients AVB3 remained permanent and in all other patients it was partially or totally regressive. After a follow-up of 2.1±2 years, pacemaker implantation was implanted in 15 patients, 1 patient with traumatic AVB3 aged 81 years, 5 patients with AVB3 during ablation, 2 with permanent AVB3 (0.2%) and 3 with transitory AVB3 and 9 patients without AVB during ablation. In these last patients, 2 had spontaneous long HV interval. Age of these patients differed from age of patients with RF-related AVB (73±14 vs 56±17) (p< 0.04). 5 patients with transitory AVB3 remained symptomatic with alternating slow junctional rhythm and sinus tachycardia.ConclusionsAVB remains frequent during AVNRT ablation (10%) but it is frequently benign and not directly related to the RF application. Permanent complete AVB is exceptional (0.2%). Patients with transitory complete AVB remain at high risk of later events as conduction disturbances or sinus tachycardia. Other AVB’s are age-related and probably without relation with ablation. Permanent or transitory 1 degree AVB seems without clinical significance

Is the Measurement of Accessory Pathway Refractory Period Reproducible?

AbstractIntroductionShort accessory pathway (AP) effective refractory period (ERP) is one of the risk factors in Wolff-Parkinson-White syndrome (WPW). The purpose of study was to evaluate the reproducibility of APERP measurement during a same electrophysiological study (EPS).MethodsEPS consisted of 2 APERP measurements performed prospectively in 77 patients for a WPW in control state (CS) at a cycle length of 400ms (n=76) and after isoproterenol (n=56).ResultsIn CS, 18 patients (24 %) had the same APERP at both measurements; 41 (54.6 %) had differences from 10 to 40ms, 17 (22.4 %) had differences >40ms. Among 45 patients with initial APERP>240ms, 7 had an APERP≤240ms at 2nd study. Among 31 patients with initial APERP≤240ms, 5 had an APERP>240ms at 2nd study. Pearson’s productmoment correlation was 0.75. After isoproterenol, 5 patients (9 %) had the same APERPs; 37 (66 %) had differences from 10 to 40ms and 14 had differences >40ms. Among 38 patients with initial APERP>200ms, 12 had an AP ERP≤200ms at 2nd study. Among 18 patients with initial APERP≤200ms, 10 had still APERP≤200ms at 2nd study. Pearson’s productmoment correlation was 0.54.ConclusionsThere are important variations of APERPs during EPS mainly after isoproterenol infusion. Therefore the values of APERPs should be interpreted cautiously

The detrimental potential of arrhythmia-induced cardiomyopathy

Here we discuss a case of arrhythmia-induced cardiomyopathy (AIC) with consecutive severe multiple organ failure. In relation to this imposing case, we discuss the significance of this potentially underestimated cause of newly occurred left-ventricular systolic dysfunction and concomitant arrhythmia. We further delineate the diagnostic algorithm and differential diagnoses of AIC

Algoritmos de Detecçao de Taquicardias Incorporado a Desfibriladores Automáticos Implantáveis. 1) Desfibriladores Monocamerais

Diversos algoritmos foram incorporados aos cardioversores-desfibriladores automáticos implantáveis (CDIs) para identificar os distúrbios do ritmo ventricular e, sobretudo, para os diferenciar de taquicardias supraventriculares que nao necessitam terapia. Esses benefícios também sao encontrados nos CDIs bicamerais que têm como benefício a detecçao atrial acoplada à detecçao do ventrículo. O objetivo dos algoritmos é de identificar todas as arritmias ventriculares (sensibilidade de 100%), para que sejam tratadas corretamente. Devem ainda evitar erros de identificaçao de arritmias supraventriculares (especificidade máxima). Infelizmente, nao é possível alcançar 100% de sensibilidade e especificidade. Além disso, todo aumento da especificidade será acompanhado por uma diminuiçao da sensibilidade. Essa diminuiçao de especificidade pode conduzir a falha na detecçao dos distúrbios do ritmo ventricular, e como conseqüência, isto é pior que o tratamento inadequado de uma taquicardia sinusal ou supraventricular

Algoritmos de Detecçao de Taquicardias Incorporado a Desfibriladores Automáticos Implantáveis. 1) Desfibriladores Monocamerais

Diversos algoritmos foram incorporados aos cardioversores-desfibriladores automáticos implantáveis (CDIs) para identificar os distúrbios do ritmo ventricular e, sobretudo, para os diferenciar de taquicardias supraventriculares que nao necessitam terapia. Esses benefícios também sao encontrados nos CDIs bicamerais que têm como benefício a detecçao atrial acoplada à detecçao do ventrículo. O objetivo dos algoritmos é de identificar todas as arritmias ventriculares (sensibilidade de 100%), para que sejam tratadas corretamente. Devem ainda evitar erros de identificaçao de arritmias supraventriculares (especificidade máxima). Infelizmente, nao é possível alcançar 100% de sensibilidade e especificidade. Além disso, todo aumento da especificidade será acompanhado por uma diminuiçao da sensibilidade. Essa diminuiçao de especificidade pode conduzir a falha na detecçao dos distúrbios do ritmo ventricular, e como conseqüência, isto é pior que o tratamento inadequado de uma taquicardia sinusal ou supraventricular

0034: Preexcitation syndrome and atrioventricular nodal reentrant tachycardia: coincidence or not?

BackgroundReciprocating tachycardia which occurs in patients with a preexcitation syndrome (PS) generally is directly related to the presence of the accessory pathway (AP) and is called atrioventricular re-entrant tachycardia (AVRT). The purpose of the study was to evaluate the incidence of re-entrant tachycardia of other nature among patients with a PS.Methods785 patients with paroxysmal tachycardia were admitted AP ablation, 294 patients with a concealed AP (group I) and 491 patients with a Wolff-Parkinson-White syndrome (WPW) (group II). Programmed atrial stimulation was performed in the control state and if necessary after isoproterenol to induce the clinical tachycardia and determine its mechanism.ResultsAVRT was induced in 760 patients (97%), 282 of group I (96%)and 478 of group II (97%) (NS). Atrioventricular nodal re-entrant tachycardia (AVNRT) was induced in 13 group I patients (4.6%) and 12 group II patients(2.5%) (NS; 0.11). In 9 group I patients (3%) and in 4 group II patients (1%) (p<0.015), both AVRT and AVNRT were induced. In patients with only induced AVNRT, slow pathway ablation was performed and accessory pathway was respected because there was no inducible tachycardia using AP and the conduction over AP was poor. These patients remained free of symptoms after ablation of AV node slow pathway. Among this population 3 families were identified as having either AVRT or AVNRT.ConclusionsIn patients with concealed or patent accessory pathway and complaining of paroxysmal tachycardia, a careful evaluation of the mechanism of tachycardia is required before ablation. Patients with concealed conduction over an AP have more frequently an association of AVRT and AVNRT than patients with a patent preexcitation syndrome. Rarely AVNRT can be the only mechanism of symptoms

AGE AND GENDER-RELATED SYMPTOMS RECURRENCE AFTER AV NODE RE-ENTRANT TACHYCARDIA

International audienc

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%