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

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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%

Estimulaçao dupla-câmara e miocardiopatias hipertróficas com obstruçao ventricular esquerda - Interesses e limites

Nas miocardiopatias obstrutivas (MCO), o gradiente sistólico intraventricular esquerdo é freqüentemente diminuído pela estimulaçao da ponta do ventrículo direito. Esta noçao, conhecida desde o fim dos anos 60, está novamente na ordem do dia, graças à estimulaçao dupla-câmara. Diante de uma MCO severa, resistente ao tratamento clínico, é recomendável efetuar uma exploraçao hemodinâmica, acoplada a uma estimulaçao AV seqüencial temporária. As variaçoes do gradiente intraventricular sao medidas pela ecocardiografia Doppler, sob estimulaçao ventricular, sincronizada pela onda P, variando-se o intervalo AV sob detecçao do átrio (P) e estimulaçao do ventrículo (V) chamado de intervalo PV. Se o gradiente cai de maneira significativa, podemos propor o implante de um marcapasso, na ausência de distúrbios da conduçao, com uma finalidade puramente hemodinâmica. O marcapasso dupla-câmara, é convenientemente selecionado e programado sob controle ecodopplercardiográfico, de forma a obter um gradiente mínimo à volume sistólico constante. Dentre 11 pacientes com MCO, 8 nao apresentavam distúrbios no sistema específico de conduçao cardíaco. Sete tiveram o gradiente significativamente diminuído sob estimulaçao ventricular direita. Seis foram submetidos a implante de MP, com o objetivo hemodinâmico. Três pacientes com distúrbios no sistema de conduçao receberam marcapassos sem exploraçao hemodinâmica prévia. A estimulaçao proporcionou melhora clínica e hemodinâmica, que se manteve após um seguimento médio de 13 meses. A única complicaçao foi o aparecimento de distúrbios do ritmo atrial, induzindo taquicardias mediadas pelo MP, quando o mesmo está mal programado ou mal protegido

Risk and Outcome after Ablation of Isthmus-Dependent Atrial Flutter in Elderly Patients

International audiencePurpose of the research To study the influence of age on the clinical presentation and long-term outcome of patients referred for atrial flutter (AFL) ablation. Age-related differences have been reported regarding the prognosis of arrhythmias. Methods A total of 1187 patients with a mean age 65±12 years consecutively referred for AFL abla-tion were retrospectively analyzed in the study. Results 445 (37.5%) patients were aged 70 (range 70 to 93) among which 345 were aged 70 to 79 years (29.1%) and 100 were aged 80 (8.4%). In multivariable analysis, AFL-related rhythmic cardiomyopathy and presentation with 1/1 AFL were less frequent (respectively adjusted OR = 0.44, 0.27–0.74, p = 0.002 and adjusted OR = 0.29, 0.16–0.52, p<0.0001). AFL ablation-related major complications were more frequent in patients 70 although remained lower than 10% (7.4% in 70 vs. 4.2% in <70, adjusted OR = 1.74, 1.04–2.89, p = 0.03). After 2.1±2.7 years, AFL recurrence was less frequent in patients 70 (adjusted OR = 0.54, 0.37–0.80, p = 0.002) whereas atrial fibrillation (AF) occurrence was as frequent in the 70– 79 and 80 age subsets. As expected, cardiac mortality was higher in older patients. Patients aged 80 also had a low probability of AFL recurrence (5.0%) and AF onset (19.0%). Conclusions Older patients represent 37.5% of patients referred for AFL ablation and displayed a <10% risk of ablation-related complications. Importantly, AFL recurrences were less frequent in patients 70 while AF occurrence was as frequent as in patients <70. Similar observations were made in patients 80 years. AFL ablation appears to be safe and efficient and should not be ruled out in elderly patients

Influence of advancing age on clinical presentation, treatment efficacy and safety, and long-term outcome of pre-excitation syndromes: a retrospective cohort study of 961 patients included over a 25-year period

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