Value of the implantable loop recorder for the management of patients with unexplained syncope.
OBJECTIVE
Recurrent syncope often remains unexplained despite extensive multidisciplinary screening. The implantable loop recorder (ILR) may be a tool to define the cardiac arrhythmias underlying syncope.


RESULTS
The study population consisted of 43 consecutive patients with unexplained syncope who underwent extensive cardiological screening and were followed with an ILR. During follow-up, 5 patients had only presyncope, 4 had palpitations, and 15 had a true recurrence of syncope. In all patients with palpitations, 3 with presyncope, and 7 with a recurrence of syncope, the ILR excluded arrhythmias. In the patients with a true recurrence, 1 had symptomatic paroxysmal atrial fibrillation (PAF) treated with drugs, 1 had polymorphic ventricular tachycardia (VT) and received an implantable cardioverter defibrillator (ICD), and 7 had asystole and received a pacemaker. Two patients with presyncope received a pacemaker for Mobitz II block and PAF with brady-tachycardia syndrome. One asymptomatic patient received a pacemaker for significant nocturnal asystole recorded by ILR. Abnormalities in the cardiac screening were observed both in patients with and without syncope, but none of these had a predictive value.


CONCLUSIONS
The ILR is a valuable and effective tool to establish an arrhythmic cause for unexplained syncope. The results of head-up tilt testing (HUTT) and electrophysiological study (EPS) are neither sufficiently sensitive nor specific enough in this patient group.
Boersma
Lucas
L
Cardiology Department, St. Antonius Hospital, Heart Lung Center Utrecht, PO 2500, 3430 EM Nieuwegein, The Netherlands. l.boersma@antonius.net
Mont
Lluís
L
Sionis
Alessandro
A
García
Emilio
E
Brugada
Josep
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000175:diagnosis*; D004562:Electrocardiography / Q000295:instrumentation*; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D017063:Outcome Assessment, Health Care; D012008:Recurrence; D013575:Syncope / Q000209:etiology*; D018667:Tilt-Table Test