ABSTRACT
There is little doubt that stenting produces superior anatomical results compared with simple balloon angioplasty. This might be expected to be associated with improved safety of endovascular treatment but there is little evidence to support this. Within CAVATAS, post-hoc subgroup analysis was done to examine the rate of stroke associated with stenting. One (2%) of 55 stented patients had a stroke at the time of stent deployment. Within 30 days of treatment, two ischemic and two hemorrhagic strokes occurred (between 2 and 11 days) in this group. There were no further strokes in the stented patients for the duration of follow-up. Hence stenting seemed safer at the time of the procedure but was associated with a similar number of delayed strokes compared to the patients treated with balloon
Table 3 Thirty-Day Outcome Events in CAVATASa
Endovascular arm
(n¼ 251) (%) Surgery arm (n¼ 253) (%) P
Major outcome events Death 2.8 1.6 NS Disabling stroke 3.6 4.3 NS Non-disabling stroke 3.6 4.0 NS Death or disabling stroke 6.4 5.9 NS Death or any stroke 10.0 9.9 NS Other outcome events Cranial nerve palsy 0 8.7 < 0.0001 Hematoma (requiring surgery or prolonging hospital stay)
1.2 6.7 < 0.0015
Myocardial infarction (non-fatal)
0 1.2 NS
Pulmonary embolus 0 0.8b NS
angioplasty. The CAVATAS trial also found that when results were ana-
lyzed by individual center experience, the average rate of stroke in the first
30 patients treated in any center was 11% but fell to 4% once an individual
center had treated more than 50 patients. This is likely to reflect the learning
curve with increasing experience but may be partly due to the increasing use
of stents as the trial progressed. CAVATAS is the only randomized study to have reported any long-
term results. Patients were followed up for a mean duration of 2 years.
Results from the 3-year survival analyses showed that both surgery and
endovascular treatment were equally effective at preventing stroke (Fig. 1).
The rates of death or disabling stoke in any arterial territory including
treatment-related events was 14.3% in the endovascular group, and 14.2%
in the patients who underwent carotid endarterectomy. Survival analysis
with adjustment for age, sex, and trial center showed no difference between
the two groups with a hazard ratio for any disabling stroke or death
(endovascular/surgery) of 1.03 (95% CI: 0.64-1.64; P¼NS). It is possible to conclude from CAVATAS that endovascular treat-
ment and carotid endarterectomy appear to have similar major risks and
benefits. The 10% 30 day rate of stroke or death in both treatment groups,
whilst relatively high, is not significantly different from the corresponding
reported rate from ECST of 7.5%. This result may have occurred purely
Figure 1 Survival analysis showing number of patients in CAVATAS free of ipsilateral stroke lasting more than 7 days.
