I | Antithrombotic therapyb (preferably unfractionated heparin) or observation (rarely used) | Not needed | 7–10 days, then 3–6 mo until healed | Antiplatelet therapy until healing |
II | Antithrombotic therapyb | Needed if neurologic symptoms or progression of dissection | 7–10 days, then 3–6 mo (until healed or definitive management) | Long-term antiplatelet therapy until healing or definitive interventional or surgical treatment |
III | Needed if symptomatic or size >1 cm | 7–10 days and then 3–6 mo or based on symptoms | Long-term antiplatelet therapy until healing or definitive treatment |
IV | Typically not beneficial | Based on symptoms | Life-long antiplatelets |
V | Direct pressure on actively bleeding area | Emergent intervention/surgery | Based on symptoms | No data (symptomatic) |