User Manual Part 4

D-20
CLINICAL STU DY - CONTAK CD
Table D-12. Echocardi ography results (continued)
CRT No CRT Between Groups
Parameter Timepoint
N
Mean ± SE
N
Mean ± SE Mean ± SE
P-value
Change at 6
Months
104 -5.4 ± 1.1 92 -0.6 ± 1.1 -4.8 ± 1.5 0.002
LVEF (%)
Post-recovery
Visit
99 26.9 ± 0.5 91 26.9 ± 0.5 0
––
Change at 6
Months
99 6.0 ± 1.1 91 2.3 ± 1.2 3.7 ± 1.7 0.029
Measures of Sympathetic Tone––Mean Norepinephrine levels (Table D-13 on
page D-20) and Mean Heart Rate (Table D-14 on page D-20) w ere examined as
markers of how CRT may influence the excessive sympathetic drive associated
with chronic heart failure.
Tab le D-13. Mean N orep inep hrin e results
All Patients
NYHA Class III/IV
Norepinephrine (pg/mL)
CRT
(N =
228)
No CRT
(N =
217)
P-value
CRT
(N =
104)
No CRT
(N = 90)
P-value
Post-recovery Visit 663 ± 19 663 ± 19
––
720 ± 31 720 ± 31
––
3 Months 651 ± 31 681 ± 32 0.479 685 ± 55 743 ± 60 0.463
6 Months 658 ± 40 738 ± 41 0.143 681 ± 75 827 ± 79 0.163
Tab le D-14. Mean heart r ate results
All Patients
NYHA Class III/IV
Heart Rate (bpm)
CRT
(N = 240)
No CRT
(N = 233)
P-value
CRT
(N = 113)
No C RT
(N = 101)
P-value
Post-recovery Visit 72.3 ± 0.6 72.3 ± 0.6
––
74.5 ± 1.0 74.5 ± 1.0
––
3 Months 70.8 ± 0.8 72.1 ± 0.8 0.20 7 4.1 ± 1.2 73.9 ± 1.3 0.94
6 Months 69.4 ± 1.0 70.2 ± 1.0 0.58 7 0.6 ± 1.6 72.5 ± 1.6 0.40
EASYTRAK Lead and System Effectiveness
It was hypothesized that the upper tolerance limit of the chronic left ventricular
pacing threshold of the EASYTRAK lead be less than 5.5 V to ensure that
an adequate safety margin exists. Chronic left ventricular pacing thresholds
- DRAFT -