A 38-year-old woman without a significant medical history or cardiovascular risk factors presented with left hemiparesis associated with subacute headache immediately after 1 hour of jogging. She had no recent head or neck trauma and did not have a history of infection or drug abuse. Clinical examination confirmed left-sided faciobrachial hemiparesis. Magnetic resonance imaging showed multifocal acute infarction zones in the middle cerebral artery territory and watershed zones, and magnetic resonance angiography revealed irregular extracranial carotid narrowing ending in a segmental high-grade intracranial stenosis (Figure) and other intracranial and extracranial arteries that were normal. Carotid duplex ultrasonography showed the presence of an intramural hematoma. Complete immunological and hematological workup results were normal. A diagnosis of carotid dissection was made and intravenous heparin treatment was started.