title: Role of extended external loop recorders for the diagnosis of unexplained syncope, pre-syncope, and sustained palpitations.
abstract: OBJECTIVE
  To assess the diagnostic yield of new external loop recorders (ELRs) in patients with history of syncope, pre-syncope, and sustained palpitations.
  
  
  RESULTS
  Since 2005, we have established a registry including patients who consecutively received ELR monitoring for unexplained syncope or pre-syncope/palpitations. The registry included 307 patients (61% females, age 58 ± 19 years, range 8-94 years) monitored by high-capacity memory ELR of two subsequent generations: SpiderFlash-A(®) (SFA(®), Sorin CRM), storing two-lead electrocardiogram (ECG) patient-activated recordings by loop-recording technique (191 patients, 54 patients with syncope, years 2005-09), and SpiderFlash-T(®) (SFT(®)), adding auto-trigger detection for pauses, bradycardia, and supraventricular/ventricular arrhythmias (116 patients, 38 patients with syncope, years 2009-12). All the patients previously underwent routine workup for syncope or palpitation, including one or more 24 h Holter, not conclusive for diagnosis. Mean monitoring duration was 24.1 ± 8.9 days. Among 215 patients with palpitations, a conclusive diagnosis was obtained in 184 patients (86% diagnostic yield for palpitation). Among 92 patients with syncope, a conclusive diagnosis was obtained in 16 patients (17% clinical diagnostic yield for syncope), with recording during syncope of significant arrhythmias in 9 patients, and sinus rhythm in 7 patients. Furthermore, asymptomatic arrhythmias were de novo detected in 12 patients (13%), mainly by auto-trigger detection, suggesting an arrhythmic origin of the syncope.
  
  
  CONCLUSIONS
  The diagnostic yield of ELR in patients with syncope, pre-syncope, or palpitation of unknown origin after routine workup was similar to implantable loop recorder (ILR) within the same timeframe, therefore, ELR could be considered for patients candidate for long-term ECG monitoring, stepwise before ILR.
authors.affiliation: Department of Cardiovascular, Cardiology Unit 3 - Electrophysiology, Niguarda Hospital, Milan, Italy emanuelateresa.locati@ospedaleniguarda.it.
authors.forename: Emanuela T
authors.initials: ET
authors.lastname: Locati
authors.affiliation: Department of Cardiovascular, Cardiology Unit 3 - Electrophysiology, Niguarda Hospital, Milan, Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Vecchi
authors.affiliation: Department of Cardiovascular, Cardiology Unit 3 - Electrophysiology, Niguarda Hospital, Milan, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Vargiu
authors.affiliation: Department of Cardiovascular, Cardiology Unit 3 - Electrophysiology, Niguarda Hospital, Milan, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Cattafi
authors.affiliation: Department of Cardiovascular, Cardiology Unit 3 - Electrophysiology, Niguarda Hospital, Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Lunati
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000453:epidemiology; D015984:Causality; D002648:Child; D015897:Comorbidity; D003937:Diagnosis, Differential; D015716:Electrocardiography, Ambulatory / Q000295:instrumentation* / Q000706:statistics & numerical data; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012042:Registries; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013575:Syncope / Q000175:diagnosis* / Q000453:epidemiology; D055815:Young Adult
keywords: Ambulatory ECG monitoring; Cardiac arrhythmias; External loop recorder; Implantable loop recorder; Palpitations; Syncope