COOK Medical Zilver, Инструкция по эксплуатации

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Acute procedure success was defined in the protocol as “vessel with <30% residual stenosis
determined angiographically immediately after stent placement and no major clinical events
before discharge.” Furthermore, patients with multiple treated vessels are considered to be
acute procedure failures if any of their treated vessels are ≥30% stenosed. The acute procedure
success was 93.3% for the pivotal study. Ten patients experienced acute procedure failure. Six
of the 10 failures had ≥30% residual stenosis, and the remaining 4 patients experienced major
adverse events (3 deaths and 1 MI) prior to hospital discharge. Two of the 3 deaths, and the
MI, were adjudicated as procedure-related by the Clinical Events Committee.
Thirty-day clinical success was defined in the protocol as “vessel with <30% residual stenosis
immediately after stent placement and no major clinical events within 30 days of implant.”
Thirty-day clinical success was 94.0% for the pivotal study. Nine patients out of the ten
patients that were considered to be acute procedure failures were also 30-day clinical failures.
ABIs were measured pre-procedure, post-procedure, and at 1- and 9-month follow-up. ABI
was seen to improve from pre- to post-procedure, as well as from pre-procedure to 1-month
and 9-month follow-ups. After the procedure, ABI was little changed at 1-month follow-up
and 9-month follow-up relative to the post-procedure value. These findings suggest that the
improvement achieved immediately after stent placement is maintained up to 9 months
post-procedure.
Ultrasound was performed no more than 3 days post-procedure and at 9-month follow-up to
assess treated vessel patency within the stented region. Patency rates were high both post-
procedure and at the 9-month follow-up (99.2% and 92.9%, respectively). Imaging was not
performed, or was inadequate for assessment, for 53 lesions immediately post-procedure and
for 52 lesions at follow-up.
The Walking Impairment Questionnaire is a measure of patient-perceived walking
performance for patients with PAD and/or intermittent claudication. Distance and speed
scores are calculated by expressing each patient’s score as a percentage of the maximum
score possible, with higher scores indicating a patient’s perception of greater walking
distance and/or speed. Table 7 presents the walking distance and speed scores pre-
procedure, at 1-month follow-up, and 9-month follow-up. The walking distance and speed
both increased from pre-procedure to 1-month follow-up, and from pre-procedure to
9-month follow-up. From 1- to 9-month follow-up there is a slight decrease in both scores.
These decreases may be due to progression of the disease rather than directly related to
stent performance. More importantly, walking distance and speed at 9-month follow-up
continues to be improved relative to pre-procedure values.
Sub-analysis of Patients with Overlapping Stents
According to the study protocol, patients were eligible to receive up to 2 stents per lesion.
As a result, some patients received overlapping stents to treat a single lesion. Twenty-four
patients (15.9%) received at least 1 pair of overlapping stents. Comparisons were made
between results from patients with non-overlapping stents and patients with overlapping
stents. Patients with overlapping stents were slightly older with a greater proportion of
males. Although patients with overlapping stents had a lower incidence of diabetes, they
had a greater incidence of high cholesterol, hypertension, and carotid, renal, and pulmonary
disease. Of the 11 major adverse events that occurred within 9 months post-procedure, 4 of
the events occurred in patients with overlapping stents. However, according to the CEC, none
of these 4 events were iliac repair related. Acute procedure success rate and 30-day clinical
success were 87.5% and 91.7%, respectively, for patients with overlapping stents. Trends in
ABIs were similar to patients with non-overlapping stents, showing an increase in ABI pre-