Background Stent placement for extracranial vertebral artery (ECVA) stenosis has largely followed cardiac stent technology. However, it remains unclear whether the newer drug eluting stents (DES) have better outcomes than older non-drug eluting stents (NDES).

Objective Compare clinical outcomes (vertebrobasilar stroke, any stroke and any death) as well as restenosis rates between different stent types (DES, newer generation NDES, and older generation NDES) in patients treated with stent placement for ECVA stenosis, through a systematic literature review of published reports.

Methods We identified ECVA studies published between January 1966 and January 2013 using a search on PubMed and the Cochrane libraries supplemented by reviewing bibliographies of selected publications based on pre-specified criteria. Case series of less than 5 patients were excluded. Rates of vertebrobasilar stroke and all cause stroke-or-death were estimated for older generation NDES, newer generation NDES, and DES at 1 month and follow up beyond 1 month. Re-stenosis rates were also compared between the 3 stent types. Fisher's exact test and generalised linear mixed models were used to compare the treatment strategies.

Results A total of 38 reports were included: 14 reporting patients treated with older generation NDES (421 patients between 1994 and 2005), 11 reporting patients treated with newer generation NDES (470 patients between 1999 and 2011), and 13 reporting patients treated with DES (278 patients between 2003 and 2010). The 30 day incidence of stroke and death was 5 (1.2%) in the older generation NDES group, 5 (1.1%) in the newer generation NDES group, and 0 (0%) in the DES group (p ≥ 0.16 comparing each pair of groups). For follow up beyond 1 month, 5 (1.2%, average follow up 18.6 mo) vertebrobasilar strokes were observed in the older generation NDES group, 9 (1.9%, 23.4 mo) in the newer generation NDES group, and 0 (0%, 16.2 mo) in the DES group (p = 0.03 comparing the newer NDES group to DES group, P ≥ 0.16 comparing the other two pairs of groups). No significant difference between groups was found comparing any stroke-or-death beyond 1-month (new NDES vs. old NDES, OR = 0.59, p = 0.40; DES vs. old NDES, OR = 0.43, p = 0.23; DES vs. new NDES, OR = 0.73, p = 0.67). Restenosis rates by digital subtraction angiography at 1-year were 61 (22.5%) for older generation NDES, 57 (16.8%) for newer generation NDES, and 31 (13%) for DES and again no pair of groups tested significantly different (new NDES vs. old NDES, OR = 0.52, p = 0.29; DES vs. old NDES, OR = 0.45, p = 0.21; DES vs. new NDES, OR = 0.88, p = 0.84).

Conclusion We found that ECVA stent placement has low rates of stroke or death for all stent groups. There were non-significant trends towards lower any stroke-or-death rates in follow up and lower rates of restenosis in the newer generation stents. DES had lower vertebrobasilar strokes in follow up compared to newer generation NDES (p = 0.03) but not older generation NDES.

Disclosures J. Kim: None. M. Memon: None. H. Zacharatos: None. K. Shea: None. K. Lakshminarayan: None. Q. Wang: None. J. Hodges: None. R. Taylor: None.