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Chapter 145 Stroke 2139

ischemic stroke and TIA. Based on the results of these trials, current results in upregulation of growth-promoting factors primarily in the
guidelines recommend CEA in patients with 70%–99% stenosis of first 4 weeks following acute stroke, but recovery can continue for
the ipsilateral carotid artery, provided the perioperative morbidity and months or years after the acute event. High levels of patient (and
mortality are estimated to be less than 6%. Although patients with family) motivation and engagement are associated with better out-
50%–69% stenosis also derive benefit from CEA, it is only recom- comes from stroke rehabilitation. Substantial evidence supports a
mended for selected patients based on age, comorbidities, time from well-coordinated multidisciplinary team care (nursing, physical
stroke/TIA, and operative risk. Time from symptom onset to CEA is therapy, occupational therapy, speech therapy, dietetics, and social
the primary determinant of the absolute risk reduction obtained with work) approach for optimal delivery of stroke rehabilitation. This care
this procedure, with maximal benefit realized when CEA is performed can be provided in the stroke unit setting or by early supported
within the first 2 weeks of symptom onset. Although CEA is the gold discharge teams in the patient’s own home. Both strategies have been
standard for patients with symptomatic significant carotid stenosis, shown to improve independence in stroke patients. For older patients
carotid stenting is an alternative option for patients with over 70% with stroke, physical rehabilitation in a long-term care facility effec-
stenosis considered to be a high operative risk for CEA. tive has been shown to improve independence.

Intracranial Stenting Chronic Secondary Prevention of Ischemic Stroke

Two trials have failed to show a benefit of intracranial stenting in Case Study
patients with symptomatic and significant (≥70%) intracranial steno-
sis. The SAMMPRIS trial reported no benefit of endovascular stent- A 72-year-old man presented with right-sided weakness and expres-
ing (self-expanding stent) in addition to aggressive medical therapy, sive aphasia 4 weeks ago. CT scan of brain revealed an ischemic stroke
compared with aggressive medical therapy alone. The trial was stopped in the left hemisphere. He was admitted to a stroke unit, and after
early because of a higher rate of stroke and death at 30 days in the completing a rehabilitation program, he was discharged home. Etio-
endovascular group. The more recent VISSIT, which compared a logical investigations included ultrasound of carotids (<20% stenosis
balloon-expandable stent in addition to medical therapy with medical of carotids), Holter monitor (no arrhythmia), and transthoracic
therapy alone, was terminated early because of higher rates of stroke echocardiography with bubble study, which revealed a small PFO.
or death at 30 days and 1 year in the endovascular group. He is known to have hypertension; his serum glucose and HbA1c
were normal. He was initiated on aspirin at the time of diagnosis.
His blood pressure in clinic today is 152/92 mmHg, and he is cur-
Prevention of Venous Thromboembolism rently receiving perindopril 8 mg daily. His fasting LDL level was
140 mg/dL.
See Chapter 142.
Antithrombotic Therapy
Acute Management of Intracerebral Hemorrhage
Current guidelines recommend aspirin, clopidogrel, or combination
Management of ICH includes both medical and surgical components. aspirin-dipyridamole for secondary prevention of noncardioembolic
Initial strategies include monitoring in an intensive care setting in ischemic stroke. The MATCH trial, which compared the combina-
appropriate patients, intubation in those with reduced consciousness, tion of clopidogrel (75 mg per day) plus aspirin (75 mg per day) with
discontinuation of antithrombotic therapy and immediate reversal of aspirin alone in patients with recent ischemic stroke or TIA found
anticoagulant therapy (Chapter 149), administration of antipyretics no reduction in the risk of major vascular events but an increased risk
for fever and insulin for hyperglycemia, and venous thromboembo- of life-threatening and major bleeding in patients treated with com-
lism prophylaxis (e.g., compression stockings). Raised ICP can occur bination therapy over 18 months of follow-up. Similar results were
as a result of the hemorrhage itself or because of secondary edema. noted in the SPS3 trial, which included patients with recent symp-
Management of increased ICP includes elevation of the head of the tomatic lacunar infarction. The subsequently published CHANCE
bed to 30 degrees, analgesia, and sedation. More aggressive therapies trial reported a lower risk of recurrent stroke at 90 days in patients
include osmotic diuretics with mannitol, drainage of cerebrospinal with TIA or minor ischemic stroke (NIHSS ≤3) treated with the
fluid using a ventricular catheter (ventriculostomy), hyperventilation, combination of clopidogrel (initial dose 300 mg then 75 mg per day
and neuromuscular blockade. Antiepileptic therapy should be used for 90 days) and aspirin (75 mg per day for first 21days) compared
for seizure control, but prophylaxis is not recommended in current with aspirin alone. The POINT trial is currently enrolling patients
guidelines. The Surgical Trial in IntraCerebral Hemorrhage (STICH) with TIA and minor ischemic stroke to compare the effectiveness of
showed no benefit of early surgery compared with medical manage- combination clopidogrel (initial dose 600 mg then 75 mg per day for
ment alone within 72–96 hours of onset of spontaneous ICH. 90 days) plus aspirin (50–325 mg per day) versus aspirin alone for
However, uncertainty remains in some patient groups, and current the prevention of ischemic vascular events (ischemic stroke, myocar-
guidelines suggest craniotomy for those with a lobar bleed of over dial infarction, and ischemic vascular death), with results expected in
30 mL within 1 cm of the brain surface. Surgical evacuation is rec- 2017. In patients with atrial fibrillation or mechanical heart valves,
ommended in patients with cerebellar hemorrhage over 3 cm in oral anticoagulation is generally recommended for secondary preven-
diameter who have evidence of deterioration, brainstem compression, tion of ischemic stroke (Box 145.2). The direct thrombin inhibitor
or hydrocephalus. Ventriculostomy with external drainage may be dabigatran and the oral factor Xa inhibitor apixaban have been shown
required for patients with intraventricular extension of ICH and a to be superior to warfarin, whereas the oral factor Xa inhibitor
deteriorating level of consciousness. Based on a large phase III trial, rivaroxaban has been shown to be noninferior to warfarin for the
current guidelines suggest that use of recombinant factor VIIa for prevention of stroke and systemic embolism in patients with atrial
acute ICH not associated with warfarin use is investigational and fibrillation. These agents are being increasingly used in clinical
should not be used outside of a clinical trial. practice and offer a number of advantages over warfarin, including a
more rapid onset of action, more predictable anticoagulant effect
enabling fixed daily dosing without need for routine coagulation
Stroke Rehabilitation monitoring, and a lower risk of food and drug interactions. Random-
ized controlled trials of extended cardiac rhythm monitoring (event
Intensive rehabilitation should commence as early as possible after loop recording) have reported increased detection rates of paroxysmal
acute stroke. Animal models of neuroplasticity suggest that training atrial fibrillation in patients with formerly unexplained ischemic