FIT Extension ARM:
Safety: In the FIT extension arm, as of 3-month FU, there were
no primary safety events resulting in a 100% (LCL 92.9%) freedom from
occurrence rate, meeting the safety goal of 89% (Figure 4). There was a
single transient PNI which resolved prior to discharge.
Effectiveness: In the FIT extension arm, analysis based on the
per protocol endpoint resulted in a freedom from event rate of 78%
(66.5% LCL), which meets the study performance goal, Figure 4. Eleven
subjects in this extension arm had failures for documented recurrence
(9), AAD use (5), and repeat procedures (3), in total, with some
subjects contributing multiple categories. Additional analysis showed an
84% freedom from recurrence of AF, 94% freedom from AFL, and 100%
freedom from AT. Though AAD usage was considerably lower in the
extension arm a pattern similar to the larger study was apparent with
AAD usage for atrial arrythmia reducing from 60% at baseline to only
8.2% at 12m FU, with only a single pt on Class 1 and 2pts on Class 3
AADs. Electroanatomic mapping data was available from only a sub-set of
patients across both study arms. Figure 5 presents two representative
cases, one of a patient where the 28mm balloon size was used in all PVs
and one of a different patient from the FIT extension where the 31mm
balloon size was used in all PVs. Fractional antral scar is calculated
to facilitate comparison of lesion extent in these two representative
patient cases.
Repeat Procedures: Repeat ablation procedures were performed in
a total of 26 patients, 11 were performed during the blanking period,
and 15 (4.6%) were performed post-blanking. In the FIT extension arm
there were 4 total repeat procedures 3 (6%) of which were performed
post blanking.