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Introduction Annotated Bibliography
Case Presentation This presentation discusses the diagnosis and treatment of a patient with a spontaneous vertebral artery dissection. Spontaneous Vertebral Artery Dissection Introduction The patient was a 29-year-old woman with a history of migraine headaches who has otherwise been in good health. She stated that earlier today she was walking in her house and talking on the phone when suddenly she started staggering to her right and fell onto her couch. She stated that when she was lying on the couch and tried to focus on things, the room was spinning and she could not make her eyes focus. She had no nausea, diaphoresis, or vomiting. She noticed no other complaints or deficits. After approximately one to two minutes, the feeling of spinning went away and the patient stated that she has had no recurrence. The only other thing she notes is that since the episode, she has a pain going up the left side of her neck and into the left side of her head. She states that this is not severe. She says that her migraines are usually in the frontal area or behind either eye. She has never had a migraine with similar symptoms in the past. Past medical history was significant for migraine headaches. Current medications were oral contraceptives and Imitrex prn. Patient doesn’t smoke cigarettes or drink alcohol. She is a housewife and mother of two children. Family history is unremarkable.
Upon physical exam: BP: 137/88, Pulse: 80, Respiratory rate: 14. The pupils were equally round and reactive. Extraocular movements were intact. The neck was supple and non-tender to palpation and she had no pain on range of motion. There were no bruits auscultated in the neck. Cardiac examination was normal with regular rate and rhythm and no murmurs. Neurological examination showed no focal deficits. Sensation was intact and deep tendon reflexes were 2 + and equal bilaterally. Toes were down going and the gate was normal. Heel-toe walking was normal. There was no dysmetria. Medical decision making: With the history of an unexplained episode of vertigo and left neck pain it was felt that vertebral artery dissection should be ruled out. The patient was given one aspirin while in the emergency department and magnetic resonance angiography was arranged. Magnetic resonance angiography showed a diminutive left vertebral artery with a focal area of absent/decreased flow and abnormal signal hyperintensity from the C1-2 through the C5-6 levels. These findings likely represent dissection of a short segment of vertebral artery.
Diagnosis
Extracranial cerebral arterial dissections occur when there is a tear in the intima of the blood vessel allowing blood to dissect in the wall of the artery. Neurological sequelae can result from this in one of two ways:
Arterial dissections may occur spontaneously or may be associated with trauma. The magnitude of the trauma may be quite trivial such as turning the head or looking upwards. Dissections may involve either the carotid or vertebral arteries. The most typical location for either carotid or vertebral dissections is at the C1-2 level. Carotid arterial dissections are more frequently reported than vertebral dissections. Carotid dissections may account for as many as 2.5% of all strokes. Seventy per cent of the patients are between the ages 35 and 50 with a mean age of 44 years. Although there is a slight predilection for females in vertebral artery dissection, carotid artery dissections occur equally in males and females. Patients with carotid or vertebral artery dissection may have an underlying arteriopathy. The major presenting features are typically stroke or transient ischemic attack associated with pain in the ipsilateral neck, face or head. With carotid dissection, an ipsilateral Horner’s syndrome will occur in 40% of patients. Headache or neck pain will often precede the onset of ischemic symptoms by hours to days. Neck pain is present in only 21% of patients with carotid dissection but over 50% of patients with vertebral dissection. Headache is present in about 60% of each. Arterial dissections occur more frequently in patients with a history of migraine, although typically the headache experienced at the time of the dissection is not migraine-like.
EvaluationThe key to diagnosing arterial dissection is suspecting the disease. Evaluation should be undertaken in any patient who presents with neurologic signs or symptoms of stroke/TIA with associated neck pain or headache. Patients with a history of arteriopathy (Marfan’s, Ehlers-Danlos, etc.) should be highly suspect. Also, a history of neck trauma, even relatively trivial, should raise the index of suspicion. The best non-invasive test for diagnosing arterial dissection is magnetic resonance angiography. If the diagnosis is suspect on MRA/MRI, angiography may be needed to confirm the diagnosis. In many cases MRI/MRA alone is sufficient to establish the diagnose. If MRA/MRI or angiography is not immediately available, carotid duplex scanning may be useful in diagnosing a carotid artery dissection. Duplex scanning may be valuable in diagnosing vertebral artery dissection with experienced operators. In patients who present with ischemic stroke or TIA symptoms, one should obtain non-contrast cranial CT as the initial test. ManagementThere are no randomized controlled trials of the management of extracranial artery dissection. Because the symptoms or sequelae of dissection are related to thrombosis and/or embolus, anticoagulation is the main stay for treatment. A patient with a documented vertebral or carotid artery dissection should be given intravenous heparin and then switched to warfarin anticoagulation. Some physicians might opt for anti-platelet therapy alone which may be quite adequate. As mentioned, there are no randomized-controlled trials to establish the superiority of one treatment over another. Re-imaging is usually done in three to six months. After the artery appears normal on MRA or angiography, anticoagulation or anti-platelet therapy can be discontinued. There is an incidence of recurrent dissection which is approximately 3% for carotids and 5% for vertebral artery dissections.
Case Outcome
The patient was admitted to the Neurology inpatient service and started on intravenous heparin. On hospital day two, the patient was begun on Coumadin to achieve an INR of 2-3. This was achieved after several days and the patient was discharged from the hospital. As an outpatient she underwent evaluation by Medical Genetics for Ehler-Danlos Type 4 syndrome, which was negative. The Medical Genetics service felt that there was no indication that the patient had any underlying arteriopathy or connective tissue disorder. Six months later, the patient had repeat magnetic resonance angiography which showed normalization of the MR angiographic appearance of the left vertebral artery since the prior examination. The MR was read as normal. The patient was discontinued from the Coumadin and has remained well.
Spontaneous Vertebral Artery DissectionAnnotated
Bibliography
1.
Silbert et al: “Headache
and Neck Pain in Spontaneous Carotid and Vertebral Artery Dissections,”
Neurology 45:1517-1522, 1995. Documents
signs and symptoms in 161 patients with dissection. 2.
Biousse et al: “Head
Pain in Non-Traumatic Carotid Artery Dissection,” Cephalgia
14:33-36, 1994. Discusses
presenting signs and symptoms of carotid artery dissection. 3.
Schierink et al:
“Heritable Connective Tissue Disorders in Cervical Artery Dissections,”
Neurology 50:1166-1169, 1998. Documents
that connective tissue disorders are common in dissection patients
although they don’t meet the classic criteria for diagnosis. 4.
Wityk: “Stroke in
a Healthy 46 year old man,”
JAMA 285(21):2757-2762, 2001. Case
presentation of spontaneous carotid dissection with a literature review. |