11% of patients had symptomatic arrhythmias.

The yield of Holter monitoring in patients with syncope depends on clinical characteristics and patient age, which affect pretest probability of an arrhythmic cause. In this study, Swiss researchers examined the diagnostic yield of 24-hour Holter monitoring in 475 consecutive patients (age, >80; 13% ?90) with syncope. Patients whose initial evaluations revealed obvious causes of syncope (e.g., orthostatic hypotension, diagnostic 12-lead electrocardiogram [ECG] finding) and those with previously implanted pacemakers were excluded. At baseline, half the patients had known structural heart disease.


Holter monitoring was diagnostic (i.e., detected an arrhythmic abnormality associated with symptoms) in 11% of patients. Most diagnostic abnormalities were bradyarrhythmias (e.g., sinus node dysfunction, atrioventricular block, atrial fibrillation with slow response) and resulted in appropriate pacemaker implantation. In addition, 10% of patients had symptoms while monitoring was normal, presumably ruling out an arrhythmic cause of syncope.


Citation(s):

Kühne M et al. Holter monitoring in syncope: Diagnostic yield in octogenarians. J Am Geriatr Soc 2011 Jul; 59:1293.