ACT I Trial Overview
The goal of the ACT I trial is to demonstrate the noninferiority of carotid stenting when compared to carotid endarterectomy for the treatment of asymptomatic extracranial carotid stenotic disease.
Medical centers throughout the United States are now enrolling patients in this trial. If you are interested in referring a potential participant, please call (408) 845-0582.
Trial design
The ACT I trial is a phase 3, randomized, parallel, 2-arm, multicenter trial.
- The randomization employs a 3:1 CAS to CEA ratio
- Approximately 1,858 patients will be enrolled
- At least 50 hospitals will be involved
- Participants will have follow-up postprocedure exams at 30 days, 6 months, and 12 months, then annually up to 5 years
Primary endpoint
The composite of any stroke, myocardial infarction, or death during a 30-day postprocedure period and ipsilateral stroke between 31 and 365 days postprocedure.
Key inclusion criteria
Both men and women are being recruited and may qualify to participate if they:
- Are at least 18 but less than 80 years old
- Have been diagnosed with severe carotid artery disease
- Single de novo lesion within the internal carotid artery, with or
without involvement of the common carotid artery
70% and 
99% stenosis by duplex ultrasound- 70% and 99% stenosis (visual estimate) by angiography
- Have not had symptoms related to carotid artery disease
(stroke or transient ischemic attack) within 180 days
- Are not at high risk for surgery
Key exclusion criteria—clinical
- Symptomatic—stroke or TIA within 180 days
- Bilateral carotid stenosis (contralateral stenosis >60% by ultrasound or angiography)
- Known cardiac sources of emboli, including paroxysmal or sustained atrial fibrillation
Key exclusion criteria—anatomical
- Aortic arch anatomy unacceptable for carotid stent placement
- Presence of any of the following in the target vessel:
- Carotid artery dissection
- Aneurysm
- Pseudoaneurysm
- Arteritis
- Fibromuscular dysplasia
- Occlusion or string sign of ipsilateral common carotid artery or internal carotid artery
- Excessive calcification of lesion
- Tortuosity and/or occlusive disease that might preclude the safe introduction of a guiding catheter sheath, cerebral protective device,
or stent
- Severe tortuosity defined as 2 or more >90-degree bend points within 3 cm of the target stenosis
- If ICA branches from the CCA at a 90-degree angle, this is considered 1 bend
