Carotid artery dissection: Difference between revisions

Jump to navigation Jump to search
VisualWikitext
No edit summary
(/* Management of Patients with Cervical Artery Dissection (DO NOT EDIT){{cite journal| author=Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL et al.| title=2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideli...)
 
(39 intermediate revisions by the same user not shown)
Line 13: Line 13:
}}
}}
{{SI}}
{{SI}}
{{CMG}}
{{CMG}}; {{AE}} {{RT}}


==Overview==
==Overview==
'''Carotid artery dissection''' is an important cause of [[stroke]] in young patients.  
'''Carotid artery dissection''' is a tear in the intima of the carotid artery wall causing separation of the wall layers.  The carotid artery supplies blood to the head and brain.  Carotid dissection is an important cause of [[stroke]] in young adults.


==Pathophysiology==
==Pathophysiology==
Arterial dissection of the [[carotid artery|carotid arteries]] occurs when a small tear in the innermost lining of the arterial wall forms.  Blood can enter into the space between the inner and outer layers of the vessel, causing narrowing (stenosis) or complete occlusion.  The stenosis that occurs in the early stages of arterial dissection is a dynamic process and some occlusions can return to stenosis very quickly.  When complete occlusion occurs, it may lead to [[ischemia]].  Often, even a complete occlusion is totally asymptomatic because collateral circulation in the head keeps the brain well perfused.  However, when blood clots form and break off from the site of the tear, the clots travel through the blood to the brain and clog one or more of the arteries directly supplying the brain, resulting in an [[ischemic stroke]], otherwise known as an [[infarct]].  Blood clots, or [[emboli]], originating from the dissection are thought to be the cause of infarction in the majority of cases of stroke in the presence of carotid artery dissection.<sup>2</sup> Cerebral infarction causes irreversible damage to the brain.  In one study of patients with carotid artery dissection, 60% had infarcts documented on neuroimaging<ref>VH Lee, et al.  Incidence and outcome of cervical dissection; a population-based study.  Neurology 2006;67:1809-1812.</ref>.
Arterial dissection of the [[carotid artery|carotid arteries]] occurs when a small tear in the innermost lining of the arterial wall forms.  Blood can enter into the space between the inner and outer layers of the vessel, creating an intraluminal hematoma which forms a thrombus causing narrowing (stenosis) or complete occlusion.  This thrombus can act as a nidus for distal embolization to the brain.  Extracranial dissection of [[internal carotid artery]] is more frequent than intracranial dissection.  The stenosis that occurs in the early stages of arterial dissection is a dynamic process and some occlusions can return to stenosis very quickly<ref name="C Lucas, 2648">{{cite journal | last1 = Lucas | first1 = C | author-separator =, | author-name-separator=  | last2 = Moulin | first2 = T| year = 1998 | last3 = Deplanque | first3 = D | last4 = Tatu | first4 = L | last5 = Chavot | first5 = D | title = Stroke patterns of internal carotid artery dissection in 40 patients | url = | journal = Stroke | volume = 29 | issue = 12| pages = 2646–2648 | pmid = 9836779 | doi = 10.1161/01.STR.29.12.2646 }}</ref>.  When complete occlusion occurs, it may lead to [[ischemia]].  Often, even a complete occlusion is totally asymptomatic because collateral circulation in the head keeps the brain well perfused.  However, when blood clots form and break off from the site of the tear, the clots travel through the blood to the brain and clog one or more of the arteries directly supplying the brain, resulting in an [[ischemic stroke]], otherwise known as an [[infarct]].  Blood clots, or [[emboli]], originating from the dissection are thought to be the cause of infarction in the majority of cases of stroke in the presence of carotid artery dissection.  Cerebral infarction causes irreversible damage to the brain.  In one study of patients with carotid artery dissection, 60% had infarcts documented on neuroimaging<ref>VH Lee, et al.  Incidence and outcome of cervical dissection; a population-based study.  Neurology 2006;67:1809-1812.</ref><ref name="C Lucas, 2648"/> .


==Causes==
==Causes==
Line 25: Line 25:
===Spontaneous===
===Spontaneous===
Once considered uncommon, spontaneous carotid artery dissection is an increasingly recognized cause of stroke that preferentially affects the middle-aged<ref>In: Neurology 2006;67:1809-1812.  Mokri B. Spontaneous dissections of internal carotid arteries. Neurologist 1997;3:104–119.</ref>.
Once considered uncommon, spontaneous carotid artery dissection is an increasingly recognized cause of stroke that preferentially affects the middle-aged<ref>In: Neurology 2006;67:1809-1812.  Mokri B. Spontaneous dissections of internal carotid arteries. Neurologist 1997;3:104–119.</ref>.
The incidence of spontaneous carotid artery dissection is low, and incidence rates for internal carotid artery dissection have been reported to be 2.6 to 2.9 per 100,000<ref>VH Lee, et al.  Incidence and outcome of cervical dissection; a population-based  study.  Neurology 2006;67:1809-1812.</ref>.


[[Observational studies]] and case reports published since the early 1980s show that patients with spontaneous internal carotid artery dissection may also have hereditary [[connective tissue disorder]]s.  These include [[Marfan syndrome]], vascular [[Ehlers-Danlos syndrome]], [[autosomal dominant]] [[polycystic kidney disease]], [[pseudoxanthoma elasticum]], [[fibromuscular dysplasia]], and [[osteogenesis imperfecta type I]]<ref>JM de Bray, et al.  History of spontaneous dissection of the cervical carotid artery.    Arch Neurol. 2005;62:1168-1170.</ref>.  However, the reports on the prevalence of hereditary connective tissue diseases in people with spontaneous dissections is highly variable, ranging from 0% to 0.6% in one study to 5% to 18% in another study.  Nevertheless, although an association exists with connective tissue disorders does exist, most people with spontaneous arterial dissections do not have associated connective tissue disorders<ref>JM de Bray, et al.  History of spontaneous dissection of the cervical carotid artery.    Arch Neurol. 2005;62:1168-1170.</ref>.
[[Observational studies]] and case reports published since the early 1980s show that patients with spontaneous internal carotid artery dissection may also have hereditary [[connective tissue disorder]]s.  These include:
 
* [[Marfan syndrome]]
* [[Vascular Ehlers-Danlos syndrome]]
* [[Autosomal Dominant Polycystic Kidney Disease]]
* [[Pseudoxanthoma elasticum]]
* [[Fibromuscular dysplasia]]
* [[Osteogenesis imperfecta#Type I|Osteogenesis imperfecta type I]]
* [[Hypertension]]
* [[Cystic medial necrosis]]
 
Nevertheless, although an association exists with connective tissue disorders does exist, most people with spontaneous arterial dissections do not have associated connective tissue disorders.
 
===Traumatic===
===Traumatic===
Carotid artery dissection is more commonly thought to be caused by trauma to the head and/or neck.  An estimated 0.67% of patients admitted to the hospital after motor vehicle accidents were found to have blunt carotid injury, including [[intima]]l dissections, [[pseudoaneurysm]]s, thromboses, or [[fistula]]s<ref>TC Fabian, et al.  Blunt Carotid Injury.  Annals of Surgery. 1996; Vol. 223, No. 5: 513-52.</ref>.  Of these, 76% had intimal dissections, pseudoaneurysms, or a combination of the two.
Carotid artery dissection is more commonly thought to be caused by trauma to the head and/or neck.  The probable mechanism of injury for most internal carotid injuries is rapid deceleration, with resultant [[hyperextension]] and rotation of the neck, which stretches the [[internal carotid artery]] over the upper cervical vertebrae, producing an intimal tear<ref>TC Fabian, et al.  Blunt Carotid Injury.  Annals of Surgery. 1996; Vol. 223, No. 5: 513-52.</ref>.  After such an injury, the patient may remain asymptomatic, have a hemispheric transient ischemic event, or suffer a [[stroke]]<ref>JH Matsuura, et al. Traumatic Carotid Artery Dissection and Pseudoaneurysm Treated With Endovascular Coils and Stent Journal of Endovascular Surgery.  1997; Vol. 4, No. 4, pp. 339–343.</ref>.
 
==Differentiating Carotid Artery Dissection from other Diseases==
Carotid artery dissection should be differentiated form the following:
* [[Vertebral artery dissection]]
* Neck trauma
* [[Headache]]
* [[Subarachnoid hemorrhage]]
 
==Epidemiology and Demographics==
* The annual [[incidence]] of spontaneous carotid artery dissection is low, and incidence rates for internal carotid artery dissection have been reported to be 2.6 to 2.9 per 100,000<ref>VH Lee, et al.  Incidence and outcome of cervical dissection; a population-based  study.  Neurology 2006;67:1809-1812.</ref>.
* [[Prevalence]] of hereditary connective tissue diseases in people with spontaneous dissections is highly variable, ranging from 0% to 0.6% in one study to 5% to 18% in another study.
* An estimated 0.67% of patients admitted to the hospital after motor vehicle accidents were found to have blunt carotid injury, including [[intima]]l dissections, [[pseudoaneurysm]]s, thromboses, or [[fistula]]s<ref>TC Fabian, et al.  Blunt Carotid Injury.  Annals of Surgery. 1996; Vol. 223, No. 5: 513-52.</ref>.  Of these, 76% had intimal dissections, pseudoaneurysms, or a combination of the two.
* Gender is not associated with an increased risk of carotid artery dissection.
 
==Complications and Prognosis==
===Complication===
* [[Ischemic stroke]]
* Retinal ischemic injury - transient loss of vision


The probable mechanism of injury for most internal carotid injuries is rapid deceleration, with resultant [[hyperextension]] and rotation of the neck, which stretches the internal carotid artery over the upper cervical vertebrae, producing an intimal tear<ref>TC Fabian, et al.  Blunt Carotid Injury.  Annals of Surgery. 1996; Vol. 223, No. 5: 513-52.</ref>. After such an injury, the patient may remain asymptomatic, have a hemispheric transient ischemic event, or suffer a stroke<ref>JH Matsuura, et al. Traumatic Carotid Artery Dissection and Pseudoaneurysm Treated With Endovascular Coils and Stent Journal of Endovascular Surgery.  1997; Vol. 4, No. 4, pp. 339–343.</ref>.
===Prognosis===
Prognosis of carotid artery dissection is favorable with 75% of patients having a good recovery.  Traumatic dissection is associated with a higher mortality rate on discharge compared to spontaneous dissection.  Two important prognostic factors include:
* Initial ischemic injury
* Collateral circulation


==Management==
==Diagnosis==
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include observation,[[anticoagulation]], [[stent]] implantation and carotid artery ligation.
===Symptoms===
Common symptoms of carotid artery dissection include:
* [[Headache]]
* [[Tinnitus]]
* [[Neck pain]]
* [[Horner syndrome]]
* Transient [[loss of vision]]
 
===Physical Examination===
====Eyes====
* [[Ptosis]]
* [[Miosis]]
 
===Laboratory Findings===
* Complete blood count
* Coagulation studies
** Prothrombin time ([[PT]])
** Activated partial thromboplastin time ([[aPTT]])
 
===Imaging===
====Helical CT angiography (CTA)====
Helical CT angiography is a reliable method to diagnose carotid artery dissections.  Findings on a helical CT angiography include:
* Narrowed eccentric lumen
* Arterial wall thickening
* Thin annular contrast enhancement
* Enlargement of the dissected artery
 
Also, the finding of a fractured cervical bone should raise the suspicion for carotid artery dissection.
 
Advantages include:
* Fast
* Noninvasive
 
====Magnetic Resonance Angiography====
[[MRA]] has evolved as an excellent imaging modality to screen and diagnose carotid artery dissection and is superior to the conventional angiography.  The classic findings on an MRA include:
* Intraluminal hematoma which appears hyperintense on fat-suppressed, axial T1 and T2 weighted images
* Mural expansion
 
Other findings include:
* Irregular vessel margins
* Filling defects
* Vascular occlusion
* Caliber changes of the vessel
 
Advantages of MRA:
* High resolution
* No radiation
* Good [[negative predictive value]]
 
Disadvantages include:
* Failure to detect the intramural hematoma with in the first 24-48 hours after carotid artery dissection
 
====Doppler Ultrasonography====
Doppler ultrasonography (DUS) is used as an initial assessment of carotid artery dissection.  Findings inlude:
* Appearance of a membrane, which is appreciated in both longitudinal and axial views
* Visualization of a false lumen even when it is thrombosed
 
==Treatment==
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include
* Observation
* [[Aanticoagulation]]
* [[Stent]] implantation
* Carotid artery ligation


==2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS: Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease (DO NOT EDIT)<ref name="pmid21282505">{{cite journal| author=Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL et al.| title=2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: executive summary. A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery. | journal=Circulation | year= 2011 | volume= 124 | issue= 4 | pages= 489-532 | pmid=21282505 | doi=10.1161/CIR.0b013e31820d8d78 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21282505  }} </ref>==
==2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS: Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease (DO NOT EDIT)<ref name="pmid21282505">{{cite journal| author=Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL et al.| title=2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: executive summary. A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery. | journal=Circulation | year= 2011 | volume= 124 | issue= 4 | pages= 489-532 | pmid=21282505 | doi=10.1161/CIR.0b013e31820d8d78 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21282505  }} </ref>==


===Management of Patients with Cervical Artery Dissection (DO NOT EDIT)<ref name="pmid21282505">{{cite journal| author=Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL et al.| title=2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: executive summary. A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery. | journal=Circulation | year= 2011 | volume= 124 | issue= 4 | pages= 489-532 | pmid=21282505 | doi=10.1161/CIR.0b013e31820d8d78 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21282505  }} </ref>===
===Management of Patients with Cervical Artery Dissection (DO NOT EDIT)<ref name="pmid21282505">{{cite journal| author=Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL et al.| title=2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: executive summary. A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery. | journal=Circulation | year= 2011 | volume= 124 | issue= 4 | pages= 489-532 | pmid=21282505 | doi=10.1161/CIR.0b013e31820d8d78 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21282505  }} </ref>===
Line 54: Line 147:


|-
|-
|bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''1.''' Antithrombotic treatment with either an anticoagulant ([[heparin]], [[low-molecular-weight heparin]], or [[warfarin]]) or a platelet inhibitor ([[aspirin]], [[clopidogrel]], or the combination of extended-release [[dipyridamole]] plus aspirin) for at least 3 to 6 months is reasonable for patients with extracranial carotid or [[vertebral arterial dissection]] associated with [[ischemic stroke]] or [[TIA]]. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])'' <nowiki>"</nowiki>
| bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''1.''' Antithrombotic treatment with either an anticoagulant ([[heparin]], [[low-molecular-weight heparin]], or [[warfarin]]) or a platelet inhibitor ([[aspirin]], [[clopidogrel]], or the combination of extended-release [[dipyridamole]] plus aspirin) for at least 3 to 6 months is reasonable for patients with extracranial carotid or [[vertebral arterial dissection]] associated with [[ischemic stroke]] or [[TIA]]<ref name="pmid17495218">{{cite journal |author=Metso TM, Metso AJ, Helenius J, ''et al.'' |title=Prognosis and safety of anticoagulation in intracranial artery dissections in adults |journal=Stroke |volume=38 |issue=6 |pages=1837–42 |year=2007 |month=June |pmid=17495218 |doi=10.1161/STROKEAHA.106.479501 |url=}}</ref><ref name="pmid17656656">{{cite journal |author=Engelter ST, Brandt T, Debette S, ''et al.'' |title=Antiplatelets versus anticoagulation in cervical artery dissection |journal=Stroke |volume=38 |issue=9 |pages=2605–11 |year=2007 |month=September |pmid=17656656 |doi=10.1161/STROKEAHA.107.489666 |url=}}</ref><ref name="pmid18303104">{{cite journal |author=Menon R, Kerry S, Norris JW, Markus HS |title=Treatment of cervical artery dissection: a systematic review and meta-analysis |journal=J. Neurol. Neurosurg. Psychiatr. |volume=79 |issue=10 |pages=1122–7 |year=2008 |month=October |pmid=18303104 |doi=10.1136/jnnp.2007.138800 |url=}}</ref><ref name="pmid19321846">{{cite journal |author=Georgiadis D, Arnold M, von Buedingen HC, ''et al.'' |title=Aspirin vs anticoagulation in carotid artery dissection: a study of 298 patients |journal=Neurology |volume=72 |issue=21 |pages=1810–5 |year=2009 |month=May |pmid=19321846 |doi=10.1212/WNL.0b013e3181a2a50a |url=}}</ref>. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])'' <nowiki>"</nowiki>
|}
|}


Line 62: Line 155:


|-
|-
|bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''1.''' Carotid angioplasty and stenting might be considered when ischemic neurological symptoms have not responded to antithrombotic therapy after acute carotid dissection. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])'' <nowiki>"</nowiki>
| bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''1.''' Carotid angioplasty and stenting might be considered when ischemic neurological symptoms have not responded to antithrombotic therapy after acute carotid dissection. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])'' <nowiki>"</nowiki>


|-
|-
|bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''2.''' The safety and effectiveness of pharmacological therapy with a [[beta-adrenergic antagonist]], [[angiotensin inhibitor]], or nondihydropyridine calcium channel antagonist ([[verapamil]] or [[diltiazem]]) to lower blood pressure to the normal range and reduce arterial wall stress are not well established. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])'' <nowiki>"</nowiki>
| bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''2.''' The safety and effectiveness of pharmacological therapy with a [[beta-adrenergic antagonist]], [[angiotensin inhibitor]], or nondihydropyridine calcium channel antagonist ([[verapamil]] or [[diltiazem]]) to lower blood pressure to the normal range and reduce arterial wall stress are not well established. ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])'' <nowiki>"</nowiki>
|}
|}


Line 75: Line 168:


{{Circulatory system pathology}}
{{Circulatory system pathology}}
 
[[Category:Grammar]]
[[Category:Cardiology]]
[[Category:Cardiology]]
[[Category:Disease]]
[[Category:Disease]]
{{WikiDoc Help Menu}}
{{WikiDoc Help Menu}}
{{WS}}
{{WS}}

Latest revision as of 16:28, 5 November 2012

Carotid artery dissection
DiseasesDB 2145

WikiDoc Resources for Carotid artery dissection

Articles

Most recent articles on Carotid artery dissection

Most cited articles on Carotid artery dissection

Review articles on Carotid artery dissection

Articles on Carotid artery dissection in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Carotid artery dissection

Images of Carotid artery dissection

Photos of Carotid artery dissection

Podcasts & MP3s on Carotid artery dissection

Videos on Carotid artery dissection

Evidence Based Medicine

Cochrane Collaboration on Carotid artery dissection

Bandolier on Carotid artery dissection

TRIP on Carotid artery dissection

Clinical Trials

Ongoing Trials on Carotid artery dissection at Clinical Trials.gov

Trial results on Carotid artery dissection

Clinical Trials on Carotid artery dissection at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Carotid artery dissection

NICE Guidance on Carotid artery dissection

NHS PRODIGY Guidance

FDA on Carotid artery dissection

CDC on Carotid artery dissection

Books

Books on Carotid artery dissection

News

Carotid artery dissection in the news

Be alerted to news on Carotid artery dissection

News trends on Carotid artery dissection

Commentary

Blogs on Carotid artery dissection

Definitions

Definitions of Carotid artery dissection

Patient Resources / Community

Patient resources on Carotid artery dissection

Discussion groups on Carotid artery dissection

Patient Handouts on Carotid artery dissection

Directions to Hospitals Treating Carotid artery dissection

Risk calculators and risk factors for Carotid artery dissection

Healthcare Provider Resources

Symptoms of Carotid artery dissection

Causes & Risk Factors for Carotid artery dissection

Diagnostic studies for Carotid artery dissection

Treatment of Carotid artery dissection

Continuing Medical Education (CME)

CME Programs on Carotid artery dissection

International

Carotid artery dissection en Espanol

Carotid artery dissection en Francais

Business

Carotid artery dissection in the Marketplace

Patents on Carotid artery dissection

Experimental / Informatics

List of terms related to Carotid artery dissection

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Raviteja Guddeti, M.B.B.S. [2]

Overview

Carotid artery dissection is a tear in the intima of the carotid artery wall causing separation of the wall layers. The carotid artery supplies blood to the head and brain. Carotid dissection is an important cause of stroke in young adults.

Pathophysiology

Arterial dissection of the carotid arteries occurs when a small tear in the innermost lining of the arterial wall forms. Blood can enter into the space between the inner and outer layers of the vessel, creating an intraluminal hematoma which forms a thrombus causing narrowing (stenosis) or complete occlusion. This thrombus can act as a nidus for distal embolization to the brain. Extracranial dissection of internal carotid artery is more frequent than intracranial dissection. The stenosis that occurs in the early stages of arterial dissection is a dynamic process and some occlusions can return to stenosis very quickly[1]. When complete occlusion occurs, it may lead to ischemia. Often, even a complete occlusion is totally asymptomatic because collateral circulation in the head keeps the brain well perfused. However, when blood clots form and break off from the site of the tear, the clots travel through the blood to the brain and clog one or more of the arteries directly supplying the brain, resulting in an ischemic stroke, otherwise known as an infarct. Blood clots, or emboli, originating from the dissection are thought to be the cause of infarction in the majority of cases of stroke in the presence of carotid artery dissection. Cerebral infarction causes irreversible damage to the brain. In one study of patients with carotid artery dissection, 60% had infarcts documented on neuroimaging[2][1] .

Causes

The cause of internal carotid artery dissection can be broadly categorized into two classes: spontaneous or traumatic.

Spontaneous

Once considered uncommon, spontaneous carotid artery dissection is an increasingly recognized cause of stroke that preferentially affects the middle-aged[3].

Observational studies and case reports published since the early 1980s show that patients with spontaneous internal carotid artery dissection may also have hereditary connective tissue disorders. These include:

Nevertheless, although an association exists with connective tissue disorders does exist, most people with spontaneous arterial dissections do not have associated connective tissue disorders.

Traumatic

Carotid artery dissection is more commonly thought to be caused by trauma to the head and/or neck. The probable mechanism of injury for most internal carotid injuries is rapid deceleration, with resultant hyperextension and rotation of the neck, which stretches the internal carotid artery over the upper cervical vertebrae, producing an intimal tear[4]. After such an injury, the patient may remain asymptomatic, have a hemispheric transient ischemic event, or suffer a stroke[5].

Differentiating Carotid Artery Dissection from other Diseases

Carotid artery dissection should be differentiated form the following:

Epidemiology and Demographics

  • The annual incidence of spontaneous carotid artery dissection is low, and incidence rates for internal carotid artery dissection have been reported to be 2.6 to 2.9 per 100,000[6].
  • Prevalence of hereditary connective tissue diseases in people with spontaneous dissections is highly variable, ranging from 0% to 0.6% in one study to 5% to 18% in another study.
  • An estimated 0.67% of patients admitted to the hospital after motor vehicle accidents were found to have blunt carotid injury, including intimal dissections, pseudoaneurysms, thromboses, or fistulas[7]. Of these, 76% had intimal dissections, pseudoaneurysms, or a combination of the two.
  • Gender is not associated with an increased risk of carotid artery dissection.

Complications and Prognosis

Complication

Prognosis

Prognosis of carotid artery dissection is favorable with 75% of patients having a good recovery. Traumatic dissection is associated with a higher mortality rate on discharge compared to spontaneous dissection. Two important prognostic factors include:

  • Initial ischemic injury
  • Collateral circulation

Diagnosis

Symptoms

Common symptoms of carotid artery dissection include:

Physical Examination

Eyes

Laboratory Findings

  • Complete blood count
  • Coagulation studies
    • Prothrombin time (PT)
    • Activated partial thromboplastin time (aPTT)

Imaging

Helical CT angiography (CTA)

Helical CT angiography is a reliable method to diagnose carotid artery dissections. Findings on a helical CT angiography include:

  • Narrowed eccentric lumen
  • Arterial wall thickening
  • Thin annular contrast enhancement
  • Enlargement of the dissected artery

Also, the finding of a fractured cervical bone should raise the suspicion for carotid artery dissection.

Advantages include:

  • Fast
  • Noninvasive

Magnetic Resonance Angiography

MRA has evolved as an excellent imaging modality to screen and diagnose carotid artery dissection and is superior to the conventional angiography. The classic findings on an MRA include:

  • Intraluminal hematoma which appears hyperintense on fat-suppressed, axial T1 and T2 weighted images
  • Mural expansion

Other findings include:

  • Irregular vessel margins
  • Filling defects
  • Vascular occlusion
  • Caliber changes of the vessel

Advantages of MRA:

Disadvantages include:

  • Failure to detect the intramural hematoma with in the first 24-48 hours after carotid artery dissection

Doppler Ultrasonography

Doppler ultrasonography (DUS) is used as an initial assessment of carotid artery dissection. Findings inlude:

  • Appearance of a membrane, which is appreciated in both longitudinal and axial views
  • Visualization of a false lumen even when it is thrombosed

Treatment

The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include

2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS: Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease (DO NOT EDIT)[8]

Management of Patients with Cervical Artery Dissection (DO NOT EDIT)[8]

Class I
"1. Contrast-enhanced CTA, MRA, and catheter-based contrast angiography are useful for diagnosis of cervical artery dissection. (Level of Evidence: C) "
Class IIa
"1. Antithrombotic treatment with either an anticoagulant (heparin, low-molecular-weight heparin, or warfarin) or a platelet inhibitor (aspirin, clopidogrel, or the combination of extended-release dipyridamole plus aspirin) for at least 3 to 6 months is reasonable for patients with extracranial carotid or vertebral arterial dissection associated with ischemic stroke or TIA[9][10][11][12]. (Level of Evidence: B) "
Class IIb
"1. Carotid angioplasty and stenting might be considered when ischemic neurological symptoms have not responded to antithrombotic therapy after acute carotid dissection. (Level of Evidence: C) "
"2. The safety and effectiveness of pharmacological therapy with a beta-adrenergic antagonist, angiotensin inhibitor, or nondihydropyridine calcium channel antagonist (verapamil or diltiazem) to lower blood pressure to the normal range and reduce arterial wall stress are not well established. (Level of Evidence: C) "

Related Chapters

References

  1. ↑ 1.0 1.1 Lucas, C; Moulin, T; Deplanque, D; Tatu, L; Chavot, D (1998). "Stroke patterns of internal carotid artery dissection in 40 patients". Stroke. 29 (12): 2646–2648. doi:10.1161/01.STR.29.12.2646. PMID 9836779. Unknown parameter |author-separator= ignored (help)
  2. ↑ VH Lee, et al. Incidence and outcome of cervical dissection; a population-based study. Neurology 2006;67:1809-1812.
  3. ↑ In: Neurology 2006;67:1809-1812. Mokri B. Spontaneous dissections of internal carotid arteries. Neurologist 1997;3:104–119.
  4. ↑ TC Fabian, et al. Blunt Carotid Injury. Annals of Surgery. 1996; Vol. 223, No. 5: 513-52.
  5. ↑ JH Matsuura, et al. Traumatic Carotid Artery Dissection and Pseudoaneurysm Treated With Endovascular Coils and Stent Journal of Endovascular Surgery. 1997; Vol. 4, No. 4, pp. 339–343.
  6. ↑ VH Lee, et al. Incidence and outcome of cervical dissection; a population-based study. Neurology 2006;67:1809-1812.
  7. ↑ TC Fabian, et al. Blunt Carotid Injury. Annals of Surgery. 1996; Vol. 223, No. 5: 513-52.
  8. ↑ 8.0 8.1 Brott TG, Halperin JL, Abbara S, Bacharach JM, Barr JD, Bush RL; et al. (2011). "2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: executive summary. A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery". Circulation. 124 (4): 489–532. doi:10.1161/CIR.0b013e31820d8d78. PMID 21282505.
  9. ↑ Metso TM, Metso AJ, Helenius J; et al. (2007). "Prognosis and safety of anticoagulation in intracranial artery dissections in adults". Stroke. 38 (6): 1837–42. doi:10.1161/STROKEAHA.106.479501. PMID 17495218. Unknown parameter |month= ignored (help)
  10. ↑ Engelter ST, Brandt T, Debette S; et al. (2007). "Antiplatelets versus anticoagulation in cervical artery dissection". Stroke. 38 (9): 2605–11. doi:10.1161/STROKEAHA.107.489666. PMID 17656656. Unknown parameter |month= ignored (help)
  11. ↑ Menon R, Kerry S, Norris JW, Markus HS (2008). "Treatment of cervical artery dissection: a systematic review and meta-analysis". J. Neurol. Neurosurg. Psychiatr. 79 (10): 1122–7. doi:10.1136/jnnp.2007.138800. PMID 18303104. Unknown parameter |month= ignored (help)
  12. ↑ Georgiadis D, Arnold M, von Buedingen HC; et al. (2009). "Aspirin vs anticoagulation in carotid artery dissection: a study of 298 patients". Neurology. 72 (21): 1810–5. doi:10.1212/WNL.0b013e3181a2a50a. PMID 19321846. Unknown parameter |month= ignored (help)

Template:WS

Retrieved from "https://www.wikidoc.org/index.php?title=Carotid_artery_dissection&oldid=790389"