Status update and interim results from the asymptomatic carotid surgery trial-2 (ACST-2).
OBJECTIVE
ACST-2 is currently the largest trial ever conducted to compare carotid artery stenting (CAS) with carotid endarterectomy (CEA) in patients with severe asymptomatic carotid stenosis requiring revascularization.


METHODS
Patients are entered into ACST-2 when revascularization is felt to be clearly indicated, when CEA and CAS are both possible, but where there is substantial uncertainty as to which is most appropriate. Trial surgeons and interventionalists are expected to use their usual techniques and CE-approved devices. We report baseline characteristics and blinded combined interim results for 30-day mortality and major morbidity for 986 patients in the ongoing trial up to September 2012.


RESULTS
A total of 986 patients (687 men, 299 women), mean age 68.7 years (SD ± 8.1) were randomized equally to CEA or CAS. Most (96%) had ipsilateral stenosis of 70-99% (median 80%) with contralateral stenoses of 50-99% in 30% and contralateral occlusion in 8%. Patients were on appropriate medical treatment. For 691 patients undergoing intervention with at least 1-month follow-up and Rankin scoring at 6 months for any stroke, the overall serious cardiovascular event rate of periprocedural (within 30 days) disabling stroke, fatal myocardial infarction, and death at 30 days was 1.0%.


CONCLUSIONS
Early ACST-2 results suggest contemporary carotid intervention for asymptomatic stenosis has a low risk of serious morbidity and mortality, on par with other recent trials. The trial continues to recruit, to monitor periprocedural events and all types of stroke, aiming to randomize up to 5,000 patients to determine any differential outcomes between interventions.


BACKGROUND
ISRCTN21144362.
Alison
A
Halliday
Richard
R
Bulbulia
William
W
Gray
Ally
A
Naughten
Anne
A
den Hartog
Antonella
A
Delmestri
Carol
C
Wallis
Stephanie
S
le Conte
Sumaira
S
Macdonald
D000368:Aged; D017130:Angioplasty / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D058070:Asymptomatic Diseases; D002317:Cardiovascular Agents / Q000627:therapeutic use; D016893:Carotid Stenosis / Q000175:diagnosis / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D016894:Endarterectomy, Carotid / Q000009:adverse effects / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology / Q000401:mortality; D018579:Patient Selection; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D015607:Stents; D020521:Stroke / Q000209:etiology / Q000401:mortality; D013997:Time Factors; D016896:Treatment Outcome
D002317:Cardiovascular Agents
Carotid artery stenosis; Carotid artery stenting; Carotid endarterectomy; Randomized controlled trial; Stroke