Cervical Artery Dissection in Stroke Study | Clinical Trial - CADISS


The goal of the trial was to compare the relative effectiveness of antiplatelet therapy versus anticoagulation therapy in patients with extracranial carotid and vertebral artery dissection.

Contribution to the Literature: The CADISS trial suggests that there is no difference between the two strategies (antiplatelet vs. anticoagulation) in mitigating the risk of recurrent stroke at 3 months; the risk of recurrent stroke is also low.  

Study Design

Patients were randomized to antiplatelet therapy with aspirin, clopidogrel, or dipyridamole (or a combination) (n = 126) versus anticoagulation with warfarin with an international normalized ratio (INR) goal of 2-3 (n = 124).

Inclusion criteria:

  • Extracranial carotid or vertebral artery dissection
  • Onset of symptoms within the past 7 days
  • Imaging evidence of definite or probable dissection
  • Total number of enrollees: 250
  • Duration of follow-up: 3 months
  • Mean patient age: 49.3 years
  • Percentage female: 30%
  • Percentage diabetics: 4%
  • History of trauma to head or neck: 20%
  • Presentation with ischemic stroke: 77%, transient ischemic attack (TIA): 18%, neck pain: 50%, amaurosis fugax: 4%, Horner’s syndrome: 24%
  • Ever smoked: 52%

Exclusion criteria:

  • Intracranial cerebral artery dissection
  • Contraindications to either antiplatelet or anticoagulation drugs, including active peptic ulceration or bleeding peptic ulcer within 1 year
  • Use of antiplatelet or anticoagulation drugs for other reasons (e.g., prosthetic heart valves) for which the treatment cannot be replaced with either antiplatelet or anticoagulant drugs
  • Pregnancy

Principal Findings:

The primary outcome, ipsilateral stroke or all-cause mortality within 3 months, occurred in 2% of the antiplatelet group versus 1% of the anticoagulation group (p = 0.63).

Secondary outcomes:

  • Any stroke: 2% vs. 1% (p = 0.63)
  • Any stroke, death, or major bleed: 3% vs. 2% (p = 1.0)
  • Major bleeding: 0% vs. 1%

There were 198 confirmed dissections on systematic analysis; the results of the per-protocol analysis were similar.


Among patients with extracranial carotid or vertebral dissection, recurrent strokes at 3 months are rare, with no difference between antiplatelet and anticoagulant therapy. This is one of the first trials performing a head-to-head comparison between the two arms.

Extracranial carotid/vertebral dissection is a rare cause of ischemic stroke, but typically occurs in younger, physically active patients. Interesting observations from this trial include the fact that only two-thirds of patients with suspected dissection had confirmed angiographic/radiographic evidence on independent review, and that only 50% of patients presented with neck pain (typically considered an important sign for diagnosis of this condition). Further longer-term follow-up of this trial is awaited.


The CADISS Trial Investigators. Antiplatelet treatment compared with anticoagulation treatment for cervical artery dissection (CADISS): a randomised trial. Lancet Neurol 2015;Feb 12:[Epub ahead of print].

Clinical Topics: Anticoagulation Management, Prevention, Vascular Medicine, Statins, Smoking

Keywords: Stroke, Anticoagulants, Cerebral Arteries, Vertebral Artery Dissection, Platelet Aggregation Inhibitors, International Normalized Ratio, Ischemic Attack, Transient, Neck Pain, Dipyridamole, Aspirin, Warfarin, Amaurosis Fugax, Horner Syndrome, Smoking

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