Evolución a largo plazo de pacientes ancianos con síncope de etiología desconocida: utilidad de los registradores de eventos implantables

Abstract

BackgroundSyncope in older people remains a diagnostic challenge due to its high prevalence and recurrence rate. Implantable loop recorders (ILR) have been established in recent guidelines as the cornerstone of unexplained syncope diagnosis, but its usefulness in older people, where syncope tends to be multifactorial in origin, remains poorly defined. Herein we review our experience with ILR in identifying the etiology of recurrent unexplained syncope in older patients after conventional management in a Syncope Unit. MethodsConsecutive patients >75years who underwent ILR implantation in our center due to unexplained syncope after complete evaluation were included. Results75 patients (26 male, mean age 79.8±3.2years) with unexplained syncope (3.7±2.3 mean syncope episodes) were included. After mean implant period of 15.5±11.6 months, 32 patients (42.6%) experienced syncope recurrence with diagnostic ILR registry. Arrhythmic causes were identified in 20 cases (AV block 8, sinus pauses/ventricular asystole 10, tachyarrhythmia 2). There were no sudden deaths during monitorization time nor in long term follow up after ILR explantation (median 48.4months, IC rank 17.9-62.5); 2 patients underwent pacemaker implantation due to complete AV block after non-diagnostic ILR. ConclusionOur results confirm usefulness and safety of ILR in diagnosis of unexplained syncope in elderly people. A significant proportion of patients had arrhythmic cause, mostly bradycardias, although neuromediated origin counts for up to 37.5%.