ASTER Trial: Contact Aspiration vs Stent Retriever Revascularization
In patients with anterior circulation LVO treated within 6 hours, does first-line contact aspiration produce higher rates of successful revascularization than first-line stent retriever?
Lapergue et al. (JAMA 2017) · doi:10.1001/jama.2017.9644 · 381 patients
Population
Included
- Age 18 years or older
- Acute ischemic stroke with anterior circulation large vessel occlusion (ICA, M1, or M2)
- Groin puncture initiable within 6 hours of symptom onset
- No protocol NIHSS threshold; enrollment required an anterior circulation occlusion judged treatable by thrombectomy
- Pre-stroke mRS 3 or less (pre-event mRS greater than 3 was an exclusion)
- Age > 18 years with no upper age limit
- Cerebral infarction in the anterior circulation
- Occlusion of the anterior circulation proven by CT angiography or MR angiography
- With or without previous intravenous thrombolysis
- Start of thrombectomy procedure within 6 hours of symptoms onset
- Patient expresses verbally his non-opposition to be enrolled in the study; in case patient cannot communicate, verbal non-opposition is obtained from his close / trusted person
Excluded
- Posterior circulation occlusion
- Pre-existing functional disability
- Contraindication to general anesthesia or sedation
- Tandem cervical lesion requiring stenting
- Life expectancy under 6 months
- Absence of indication for thrombectomy
- Contraindication for thrombectomy
- Presence of cerebral infarction of the posterior circulation
- Occlusion of the cervical carotid artery
- Allergy to x-ray contrast products
- Patient was bedridden or using a wheelchair most of the day (pre-event modified Rankin Scale score > 3) prior to stroke
- Pregnancy or breastfeeding
- Patient under legal protection
- No affiliation to health insurance
- Lack of access route for catheterization
Source: ClinicalTrials.gov NCT02523261· Retrieved 2026-06-08
Primary Outcome: Successful Revascularization (mTICI 2b-3)
Procedural endpoint, not a clinical outcome measure
Procedural endpoint, not clinical outcome
The chart shows end-of-procedure revascularization rates, not 90-day disability. mRS 0-2 at 90 days was 45.3% (aspiration) vs 50.0% (stent retriever); P = 0.38. No significant clinical difference between strategies.
Difference not statistically significant (p = 0.53); no difference band is drawn.
mTICI 2b-3 Revascularization
Study Arms
- Agent
- Direct aspiration first-pass technique (ADAPT): large-bore aspiration catheter, first-line
- Route
- Endovascular (transfemoral)
- Co-interventions
- IV thrombolysis (alteplase) first if eligible, then transfer to angiography; long sheath in distal cervical vasculature; aspiration catheter advanced to proximal thrombus with continuous aspiration; GA or conscious sedation per operator; ≥3 attempts with assigned technique required before switching (rescue at operator discretion: stent retriever, combined, or angioplasty±stenting).
Aspiration-first arm, n=192; rescue treatment after first-line strategy in 32.8% (63/192). Lapergue JAMA 2017 Methods p.444-445.
- Agent
- Stent retriever, first-line (Solitaire and Trevo most commonly used)
- Route
- Endovascular (transfemoral)
- Co-interventions
- IV thrombolysis (alteplase) first if eligible, then transfer to angiography; balloon-guide catheter in cervical ICA; stent retriever deployed across occlusion; proximal flow arrest by balloon-guide inflation during retrieval; GA or conscious sedation per operator; ≥3 attempts before rescue crossover.
Stent-retriever-first arm, n=189; per-protocol balloon-guide. Lapergue JAMA 2017 Methods p.444-445.
Trial Design
Type
- Randomized open-label, blinded endpoint trial
- First-line contact aspiration vs first-line stent retriever
- Anterior circulation LVO within 6 hours
- Conducted in 8 French comprehensive stroke centers
Timeline
Enrolled 2015-2016
N
381
Enrollment
French multicenter randomized open-label blinded-endpoint (PROBE) trial enrolling 381 patients at 8 comprehensive stroke centers between 2015 and 2016 (Lapergue JAMA 2017).
ClinicalTrials.gov
NCT02523261Bedside Pearl
ASTER showed no significant difference between aspiration-first and stent-retriever-first for revascularization or 90-day outcomes, but rescue treatment was used in 32.8% of the aspiration arm versus 23.8% of the stent-retriever arm. Choice of first-line technique is operator-dependent; readiness to switch techniques is part of getting equivalent outcomes.
See also