User Manual

6. CLINICAL STUDIES
Trial, a uniform protocol was used for V-V programming. This protocol required all patients to
undergo echo-guided V-V delay optimization before randomization (2 to 14 days post-
implant). The optimal V-V delay was determined by finding the programmable V-V delay and
ventricular chamber pacing order (RV then LV, or LV then RV) providing the maximum time
velocity integral (TVI or VTI) across the left ventricular outflow tract (LVOT).
Only those patients randomized to the Test arm were required to be programmed per the
optimization protocol for the V-V delay.
Of the 177 patients that presented at randomization, 3 had Model 617 which does not have
V-V programmability hence the inability to optimize. Of the remaining 174 patients, 154
(89%) were tested per the V-V optimization protocol. One hundred forty-nine (149) of the
154 patients who were tested per the V-V optimization protocol were programmed per the
recommended or randomized V-V delay (97%). Thirty-one (31) patients were programmed
to BiV synchronous (V-V delay 0ms), 46 were programmed to Sequential BiV (LV then RV),
22 were programmed to Sequential (RV then LV), and the remaining 50 patients were
randomized to RV only.
A sub-analysis of the composite endpoint comparing the subset of CRT-D patients with
optimized V-V delays vs. the subset of patients that did not undergo V-V delay optimization
demonstrated similar results in both groups. The CRT-D patients who did not undergo V-V
delay optimization showed a smaller improvement in the composite endpoint, although the
sample size did not permit conclusions based on data from this subset.
SORIN – INTENSIA SonR CRT-D 184 – U150A
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