3.1 Baseline patient characteristics and ILR implants in
follow-up
The study included 348 patients who were implanted with an ILR for
unexplained syncope. Follow-up data were available in 309 patients (88%
out of total implanted patients), figure 1. The mean age was 59 years
(range 4-93 years), 49% was female. The median number of syncope was 3
[1-3]. Baseline patient and electrocardiographic findings are
summarized in table 1. Baseline conduction abnormalities on ECG were
present in 13% of the patients. 8.7% had a first degree
atrioventricular block, 2.3% left bundle branch block (LBBB), 7.4%
right bundle branch block (RBBB), 2.3% bifascicular block and 0.6% had
a trifascicular block. During work-up for syncope, all of the patients
had a negative 24h Holter monitoring, and 46% underwent head up tilt
testing, which was negative. Electrophysiologic (EP) study was performed
in 59% of the patients (and negative), before implantation of the ILR.
Numbers of patients implanted with different ILR models and according to
different manufacturers are specified in figure 2. Two out of three
patients (67%) received an ILR manufactured by Medtronic, 29% Abbott
and 3% Biotronik.