Table Of ContentO A P N
OXFORD AMERICAN POCKET NOTES
Antithrombotic Therapy
in the Prevention of
Ischemic Stroke
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O A P N
OXFORD AMERICAN POCKET NOTES
Antithrombotic Therapy
in the Prevention of
Ischemic Stroke
By
Richard C. Becker, M.D.
Professor of Medicine,
Duke University Medical Center
Frederick A. Spencer, M.D.
Professor of Medicine in Cardiology and Hematology,
McMaster University Faculty of Health Sciences
1
1
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ISBN: 978-0-19-539432-0
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ANTITHROMBOTIC THERAPY
CONTENTS
Introduction and Epidemiology 1
Pathophysiology 2
Regulatory Factors in Thrombus Formation 2
Cellular Interactions in Atherothrombosis 6
Classifi cation of Stroke 7
Managing Risk Factors for Recurrent Stroke 9
Antithrombotic Therapy for Prevention of Recurrent
TIA and Stroke 13
Aspirin 16
Mechanism of Action 16
Pharmacokinetics 16
Adverse Eff ects 17
Aspirin Administration in Clinical Practice 18
Secondary Prevention of Vascular Events
and Stroke 21
Aspirin Dosing in Prevention of Recurrent
TIA/Stroke 21
Thienopyridines (Clopidogrel, Ticlopidine,
and Prasugrel) 23
Mechanism of Action 23
Clopidogrel 23
Pharmacokinetics 23
Absorption 25
OOOAAAPPPNNN
Adverse Eff ects 25
Prevention of Vascular Events 26
Ticlopidine 29
Prasugrel 29
Dipyridamole, Extended-Release Dipyridamole/Aspirin
Combination (Aggrenox) 31
Mechanism of Action 31
Pharmacokinetics 32
Pharmacodynamics 32
Adverse Eff ects 32
Administration in Older Patients 33
Clinical Experience 33
Cilostazol 39
References 39
ANTITHCOROROMNBOATRYIC S TTHENERTAINPGY
DISCLOSURES
Dr. Becker has nothing to disclose.
Dr. Spencer received an honorarium from the Drug Safety
Monitoring Board for EISAI and Sanofi studies. He has also
received an honorarium from Canadian National Coordinator
for BMS and Pfi zer studies.
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ANTITHROMBOTIC THERAPY
INTRODUCTION AND EPIDEMIOLOGY
Each year in the United States, about 795,000 people
experience a new or recurrent stroke. About 610,000 of
these are fi rst attacks and 185,000 are recurrent attacks.
Preliminary data from 2006 indicate that stroke accounted
for about 1 of every 18 deaths in the United States, making
stroke the third-leading cause of death.
Transient ischemic attacks (TIAs, also termed mini-strokes)
have been shown to be major risk factors and harbingers for
major stroke: approximately 15% of all strokes are heralded
by a TIA. In population-based studies, the age- and gender-
adjusted incidence rates for TIA range from 68.2 to 83 per
100,000. After a TIA, the 90-day risk of stroke and the risk
of death after 1 year increase signifi cantly.1
The major diff erences in defi ning ischemic stroke versus
TIA have to do with the duration of symptoms: an ischemic
stroke is defi ned as acute onset of neurologic symptoms last-
ing longer than 24 hours, or where radiographic evidence
of an ischemic event exists in patients with loss of symptoms
within 24 hours. A TIA is an event that lasts less than 24
hours and that lacks evidence of pathology on radiographic
studies.2 There is signifi cant overlap in terms of clinical pro-
cess and pathophysiology between TIA and stroke, resulting
in largely similar treatment and monitoring regimens in both
conditions.
1
