¿Es imprescindible un EEF antes de indicar un marcapasos a pacientes con síncope y bloqueo bifascicular? Good morning, Ladies and gentlemen Dr. Alboni, Dr. Moya Miguel Álvarez, Luís Tercedor, Antonio Arrebola, Juan Jiménez, Sebastián Galdeano, Pablo Santiago, Rafael Melgares. Servicio de Cardiología Hospital Universitario Virgen de las Nieves Granada

Introducción En pacientes con síncope de origen desconocido (SOD) y bloqueo bifascicular (BFB) el bloqueo AV (BAV) es la causa más frecuente de las recurrencias. El estudio electrofisiológico (EEF) está indicado en pacientes con SOD y BFB. Si el EEF es positivo es necesario el implante de un marcapasos Si es negativo podría emplearse un registrador de eventos para llegar al diagnóstico. El BAV paroxístico es la causa más frecuente de las recurrencias sincopales en pacientes con SOD y EEF negativo. Los tipos de síncope se pueden predecir por los síntomas

An electrophysiological study is indicated in patients with syncope and BBB when non-invasive tests have failed to make the diagnosis. Pacing is indicated in patients with BBB and positive EPS (Class I, Level B) Pacing should be considered in patients with unexplained syncope and BBB (Class IIa, Level C) The most recent guidelines for the management of syncope have stated that an electrophysiological study is indicated in patients with syncope and bundle branch block when non-invasive tests have failed to make the diagnosis. Pacing is indicated in patients with BBB and positive EPS (Class I, Level B). Pacing should be considered in patients with unexplained syncope and BBB (Class IIa, Level C) A Moya, et al. Eur Hear J 2009

Objetivo Evaluar si el tipo de síncope puede predecir los resultados del EEF en pacientes con BFB. The main objective of our study was to evaluate whether the type of syncope predicts the results of electrophysiological study in patients with bifascicular block.

Inclusión Exclusión Pacientes remitidos a UA Bloqueo bifascicular Síncope origen desconocido Bloqueo bifascicular Bloqueo de rama izquierda o Bloqueo de rama derecha y Hemibloqueo anterior izdo o Hemibloqueo posterior izdo Función ventricular preservada No Cardiopatía Cardiopatía Hipertensiva Masaje seno carotídeo: Negativo Cardiopatía estructural CI, MD, MH, DAVD ICC FEVI deprimida (<45%) Cardiopatía “eléctrica” Síndrome Brugada, SQTL, Síndrome WPW Fármacos antiarrítmicos Clase I Amiodarona, sotalol Bloqueo de rama alternante Hipotensión ortostática Contraindicación para EEF Patients with U O S referred to our AU were included if they reached the inclusion criteria: BFB on ECG, preserved LVSF in patients with no SHD or HCD and a negative CSM. Patients were not included if they had any SHD, HF, depressed LVSF, electrical cardiac disease, current treatment with AAD, orthostatic hypotension, alternating BBB or contraindication for EPS.

Métodos Análisis retrospectivo Anamnesis y exploración física previa a EEF Masaje seno carotídeo TA decúbito y bipedestación Clasificación de síncope Sospecha BAV paroxístico Grupo A Neuromediado Grupo B Origen incierto Grupo C Indicación posterior de MP en función del resultado del EEF, tilt test y registrador insertable de eventos: Cardiólogo referidor The data analysis was retrospective. Clinical history and physical examination (CSM and BP measure) were performed prior the EPS; In regard the non-invasive test ssyncope was catalogued in three groups: A, suspected AVB; B, neurally mediated and C, unexplained syncope PM, ILR and TT were indicated by their cardiologist

Estudio Electrofisiológico V1 ADa His aVD Three or two tetrapolar 5-french-catheters were inserted in high right atrium, His bundle region and right ventricle. Intervals were measured in basal state. incremental atrial pacing was then performed. Programmed stimulation was performed to induce atrial and ventricular tachyarrythmias. Procainamide infusion was administered if necessary. The infusion was stopped because of systemic hypotension.An EPS was considered positive if:……..These positive criteria were the same as those published on the recent guidelines.

Enfermedad del Sistema His-Purkinje Atrial Pacing (AP) + HV>70 ms Test de Procainamida (PA) +

Resultados 50 pacientes incluidos Diagnóstico clínico Grupo A. Sospecha BAV: 27 No pródromos: 22 (84,5%) Pródromos < 5 sec: 5 (15,5%) Grupo B. Neuromediado: 12 Pródromos típicos 12 (100%) Grupo C. Origen incierto: 11 No pródromos 3 (27%) Náusea/fatiga Pródromos > 5 sec 8 (73%) Mareo, visión borrosa Fifty patients were included. Absence of prodromes was the main symptom to distinguish between the types of syncope. 27 were classified into the group A, 22 of them had no prodromes and five had prodromes lasting less than 5 seconds. Twelve patients had neurally mediated syncope with typical autonomic prodromes. Eleven patients had unknown syncope. Three had no prodromes but during the recovery they had symptoms typical of neurally mediated syncope. Eight had prodromes lasting more than 5 seconds but there were not typical autonomic prodromes. S Sud, et al. Heart Rhythm 2009

Características basales Grupo A Sospecha- BAV Grupo B Neuromediado Grupo C Origen incierto Hombres (%) 62 50 45 Edad 72±5.6 68±8 65±11* RS (%) 93 100 No cardiopatía (%) 63 73 83 Diabetes (%) 15 18 8 Presíncope (%) 29‡ Nº síncope-2 a. 2.7±2.2 3.4±3.3 8.8±10.4# Evolución meses 10.2±20‡ 43.4±61.3 46.5±43.1 TCE (%) 44 17† 55 Características basales The patients of group C were younger than the patients of group A. The majority of patients was in NSR, and had no SHD. Patients of group A had a lower percentage of presyncope and a lower evolution time. The patients of group C had more syncopal episodes in the 2 previous years. The patients of group B had a lower percentage of head trauma related to syncope.

ECG 12 derivaciones Grupo A Sospecha- BAV Grupo B Neuromediado Grupo C Origen incierto BRI BRD+HAI BRD+HPI 13 (48) 1 (4) 6 (50) 5 (45,5) 6 (55,5) QRS ms 150±19 145±26 146±13 PR ms 194±30 179±29 182±30 QTc ms 455±45 445±45 455±25 There were no differences in the 12-lead ECG. QRS-width, length of PR and corrected-QT intervals.

Resultados del EEF 73±12 55±11* 66±12 (n=9) HV ms HV interval was equal to or longer than 70 ms in 67% of patients of group A, in 33% in group C and in only 8% of patients of group B (HV was 70 ms). Two patients of group C suffered complete AVB due to injury on right bundle branch, one transient and other permanent. Basal AP was positive in 4 patients of group A (2 patients with long HV interval and 2 with normal HV conduction time) and in one patient of group C. PA test was not performed in patients with AP+ and HV interval longer than 90 ms. PA test was positive in 7 patients of group A. PA test was positive in one patient of group C who had an HV>70 ms. PA was negative in all patients of group C who had a normal HV conduction time. No patients with neuromediated syncope had an AP positive response or a positive PA test. AP= Estimulación auricular progresiva PA= Test Procainamida

BAVt: Bloqueo AV traumático AP= Estimulación auricular progresiva A PM was indicated and was implanted in 23 patients of group A with a positive EPS. An ILR was implanted in two patients and no device was implanted in another two. A PM should have been implanted in one patient of group B but it was not implanted in this patient. An ILR was implanted in two (one of them with HV=70 ms). In group C a PM should have been implanted in 4 patients with a positive EPS, but it was implanted in one patient more who had an spontaneous 2nd degree suprahisan AVB, an ILR was implanted in four patients and no device in 2 patients. BAVt: Bloqueo AV traumático AP= Estimulación auricular progresiva PA= Test Procainamida RIE: Registrador Insertable de eventos

Syncope recurrence and AVB or asystolic pause in AF were registered in five patients with an ILR. In one-group B patient NSR was rgisterd during a presyncope episode. ILR was explanted because battery in two patients.

Medio Plazo A PM was implanted in all patients in group A with a positive EPS. An ILR was implanted in two patients and no device was implanted in another two. PM was not implanted in any patient of group B. An ILR was implanted in two (one of them with HV=70 ms). In group C a PM was implanted in 5 patients with a positive EPS, an ILR was implanted in four and no device in 2 patients.

Conclusiones Las características clínicas del síncope pueden predecir los resultados del EEF en pacientes con bloqueo bifascicular y cardiopatía no significativa. Pacientes con sospecha de BAV paroxístico tienen una elevada probabilidad de enfermedad del sistema His-Purkinje. La indicación de MP podría realizarse sin EEF previo Un EEF o un RIE podrían ser la primera estrategia en pacientes con síncope de origen incierto tras historia clínica. Los pacientes con síncope neuromediado tienen una casi nula probabilidad de enfermedad del sistema His-Purkinje. El seguimiento podría ser la mejor estrategia ISSUE 2 Clinical features of syncope can predict the results of EPS in patients with bifascicular block and no significant SHD. Patients with AV-block suspected syncope have a high probability of His-Purkinje system disease. Pacemaker indication could be performed independently of EPS An EPS or an ILR could be the first strategy in patients with unexplained syncope after clinical history Patients with neurally-mediated syncope have a near null probability of His-Purkinje system disease. Observation could be the best strategy Other strategy could be that proposed in ISSUE 2