Vertebral Arterty Dissection
Update February 7, 2020
A 35-year-old female presents for worsening right-sided posterior neck pain that radiates to her right occiput. The pain has been dull and intermittent for about a week and associated with some right posterior scalp tenderness. She became alarmed today because she felt dizzy after her workout. She describes several minutes of vertigo that resolved a few hours ago. Now, sitting in your examination room, she denies vision changes, muscle weakness, numbness, paresthesia, swallowing problems, and speech deficits. Since she's training for a "Viking's Valor Race," she has intensified her workouts in the past few weeks, lifting heavier weights. She is relatively healthy but does take lisinopril for hypertension due to fibromuscular dysplasia. Her vitals are normal. Her neurological examination is normal.
The most appropriate next step in the care of this patient is:
You will be able to view all answers at the end of your quiz.
The correct answer is E. You answered E.
The correct answer is "E." This patient is presenting with symptoms concerning for vertebral artery dissection. Extracranial arterial dissections of the head and neck are relatively more common causes of stroke in young adults compared with older adults. Fortunately, many patients experience symptoms of dissection (typically head and/or neck pain, although a Horner syndrome can develop in patients with carotid artery dissection) prior to having a stroke and can be identified early if the physician is attentive and orders the appropriate test. In this case, "D" is not the right test. Head CT would be unlikely to show anything since she does not currently have neurologic signs or symptoms. Even with a CT angiogram of the brain, the extracranial neck arteries (where the problem exists) would not be visualized. Thus, the imaging must include the head and neck and must provide views of the arteries. If "E" is not available, CTA of the head and neck is a reasonable alternative. Classically, an angiogram was used to make the diagnosis, but it is more common now to use MRA or CTA. Of note, patients with fibromuscular dysplasia are more likely to have vertebral and carotid artery dissections, but the vast majority of patients with vertebral or carotid dissection do not have any known connective tissue disorder. Case series of dissections often describe a minor trauma (e.g., weight lifting, amusement park rides, various sports, "fender bender" accidents, chiropractic neck manipulation, etc.) prior to the onset of symptoms.
Determine Size by Ultrasound
Measure the diameter of the outside wall in a posterior-anterior direction and a right to left direction.
| < 5 cm | > 5 cm | Nondiagnostic |
Address modifiable risk factors
- Hypertension
-
Obesity
-
Atrial fibrillation (AF) / cardiac disease
-
Diabetes
-
Dyslipidemia
-
Excessive alcohol intake
-
Physical inactivity
-
Smoking
-
Diet
If cost were NOT an issue, which of the following drugs/drug combinations would be the ideal regimen for the secondary prevention of stroke?
You will be able to view all answers at the end of your quiz.
The correct answer is B. You answered D.
The correct answer is "B." Both clopidogrel and aspirin with extended release dipyridamole reduce the risk of stroke to a greater degree than aspirin alone in patients with a history of stroke. There is evidence to suggest that aspirin with extended release dipyridamole is the overall superior drug. Clopidogrel and aspirin should not be used together for secondary stroke prevention, as there is no significant benefit compared with clopidogrel alone.
A 75-year-old right-handed man presents to the emergency department (ED) with dizziness that started 5 hours ago. His dizziness consists of a spinning sensation and he feels off balance as he walks. He reports coughing when trying to drink water earlier, but otherwise notes no other symptoms. He has an unremarkable past medical history and is taking no medications. On examination, he is found to have left-sided ptosis and left facial numbness to pinprick. Gag reflex is absent. Motor examination is otherwise unremarkable. Sensory examination revealed decreased pinprick sensation of the right arm and leg. He is unsteady while walking, tending to lean leftward.
What is the most likely diagnosis in this patient?
The correct answer is "D." Although dizziness can be associated with all of the above disorders, a brain stem stroke is the most likely answer. The associated symptoms of ptosis (suggestive of Horner syndrome), absent gag reflex with patient report of possible dysphagia, and crossed sensory findings (left side face, right side body) are most consistent with brain stem localization. In peripheral etiologies of vertigo ("A," "B," and "E"), one would not expect sensory phenomena, ptosis, or swallowing difficulties. In BPPV, one would expect brief attacks, lasting seconds to minutes, and not a prolonged attack. In Ménière's, there is often some history of tinnitus and/or hearing loss (low frequency initially). A pure cerebellar stroke would not be expected to have sensory findings.
Content 3
A 62-year-old man presents with an asymptomatic abdominal aortic aneurysm (AAA) measuring 4.8 cm in diameter. The patient’s past medical history is significant for hypertension and stable angina. He has a 40-pack-year smoking history. His current medications include aspirin, a beta-blocker, and nitrates. The patient describes himself as an active man who just retired and plays 18-holes of golf two times a week. On examination, the carotid pulses and upper extremity pulses are normal. The abdomen is nontender with a prominent aortic pulse. Pulses in the femoral and popliteal regions are readily palpable and appear more prominent than usual.
-
For completeness the nonmodifiable risk factors are listed below:
-
Age
-
Gender
-
Family history
-
Ethnicity
-
Previous TIA or stroke
-
Diet, sodium, exercise, weight, smoking, alcohol intake
All patients should receive information and counseling about possible strategies to modify their lifestyle and risk factors.
Encourage a balanced diet
-
High in fresh fruits, vegetables, low-fat dairy products, dietary and soluble fiber, whole grains and proteins from plant sources, and low in saturated fats, cholesterol, and sodium.
-
Most Americans consume excessive amounts of sodium leading to increasing prevalence of hypertension.4
-
One teaspoon of salt contains approximately 2300 mg (the upper limit recommended).
Encourage exercise—there are many reasons to do this
-
A meta-analysis published by Lee et al5 reviewed 23 studies (18 cohort and 5 case control studies), examining the association between exercise and stroke incidence and mortality.
-
Highly active people were reported as having a 27% lower risk of stroke than people who were designated as low active.
-
Moderately active people also demonstrated a significantly reduced risk of stroke when compared to the low active group. The benefits of both high and moderate levels of activity were reported for both ischemic and hemorrhagic strokes.
Maintain healthy weight—goal BMI of 18.5 to 24.9 kg/m2.
Stop smoking
-
Smokers who smoke 20 or more cigarettes per day have 2 to 4 times the risk of stroke as compared to nonsmokers. This risk is dose-dependent so the more you smoke, the greater the risk of stroke. Heavy smokers are more at risk than light smokers. Light smokers are more at risk than nonsmokers. Stopping smoking has been shown to reverse risk of cardiovascular disease. This highlights the cessation of smoking as a leading effective intervention available to reduce risk of stroke.
Alcohol (in moderation)6
-
A meta-analysis by Reynolds et al4 revealed that individuals who consumed 1 to 2 drinks per day had the least risk of stroke and those that had more than 5 drinks per day had the most risk of stroke when compared to a group of abstainers. (J-shaped relationship as abstaining had a higher risk than 1-2 drinks/day, making the first part of the J.)
-
Heavy drinking (more than 5 drinks per day) was associated with the risk of hemorrhagic stroke.
-
Irregular and binge drinking (more than 5 drinks at one time) have been associated with an increased risk of hemorrhagic stroke.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A. The diagnosis in this patient is stroke, characterized by the sudden onset of focal neurologic deficits that persist for at least 24 hours owing to an abnormality of the cerebral circulation. The focal symptoms and signs that result from stroke correlate with the area of the brain supplied by the affected blood vessel. In this case, the patient has weakness and sensory loss on the right side. These symptoms suggest involvement of the left middle cerebral artery or at least its associated vascular territory. The vascular territory supplied by the middle cerebral artery includes the lateral frontal, parietal, lateral occipital, and anterior and superior temporal cortex and adjacent white matter, as well as the caudate, putamen, and internal capsule.
B. Risk factors for stroke include age, male sex, hypertension, hypercholesterolemia, diabetes, smoking, heavy alcoholconsumption, and oral contraceptive use.
C. Stroke is classified as either ischemic or hemorrhagic in origin. Ischemic stroke may result from the thrombotic or embolic occlusion of the vessel. Hemorrhagic stroke may result from intraparenchymal hemorrhage, subarachnoid hemorrhage, subdural hemorrhage, epidural hemorrhage, or hemorrhage within an ischemic infarction. Given the CT scan result, it is likely that this man has sustained an ischemic, rather than a hemorrhagic, stroke. Hemorrhagic and ischemic strokes can be difficult to differentiate on clinical grounds, but the former often produce a less predictable pattern of neurologic deficits. This is because the neurologic deficits in hemorrhagic stroke depend both on the location of the bleed and on factors that affect brain function at a distance from the hemorrhage, including increased intracranial pressure, edema, the compression of neighboring brain tissue, and rupture of blood into the ventricles or subarachnoid space.
D. The most likely underlying cause of stroke in this patient is atherosclerosis. Atherosclerosis arises from vascular endothelial cell injury, often caused by chronic hypertension or hypercholesterolemia, both present in this man. Endothelial injury stimulates the attachment of circulating monocytes and lymphocytes that migrate into the vessel wall and stimulate the proliferation of smooth muscle cells and fibroblasts. This results in plaque formation. Damaged endothelium also serves as a nidus of platelet aggregation that further stimulates the proliferation of smooth muscle and fibroblasts. The plaques formed may enlarge and occlude the vessel, leading to thrombotic stroke, or they may rupture, releasing emboli and causing embolic stroke.
History of TIA
History of previous stroke
hypertension,
atherosclerosis, cardiac disease (eg, atrial fibrillation, myocardial infarction, and valvular disease),
diabetes,
carotid stenosis,
dyslipidemia,
hypercoagulable states,
tobacco, and
alcohol use.
Stroke occurs when
thrombosis,
embolism, or hemorrhage interrupts cerebral oxygenation and causes the death of neurons in the brain.
This leads to deficits in cognition and in motor and sensory function.
- Strokes are generally classified as ischemic or hemorrhagic.
- Ischemic strokes are caused by large artery atherosclerosis (embolus or thrombosis), small vessel occlusion (lacunar), or cardioembolism (often from atrial fibrillation). Most strokes (85%) are ischemic, and 90% affect the middle cerebral artery
-
Ischemic Stroke Syndromes
Syndrome
Symptoms
Dominant hemisphere
Contralateral numbness and weakness, contralateral visual field cut, gaze preference, dysarthria, aphasia
Nondominant hemisphere
Contralateral numbness and weakness, visual field cut, contralateral neglect, dysarthria
Anterior cerebral artery
Contralateral weakness (leg > arm); mild sensory deficits; dyspraxia
Middle cerebral artery
Contralateral numbness and weakness (face, arm > leg); aphasia (if dominant hemisphere)
Posterior cerebral artery
Lack of visual recognition; altered mental status with impaired memory; cortical blindness
Vertebrobasilar syndrome
Dizziness, vertigo; diplopia; dysphagia; ataxia; ipsilateral cranial nerve palsies; contralateral weakness (crossed deficits)
Basilar artery occlusion
Quadriplegia; coma; locked-in syndrome (paralysis except upward gaze)
Lacunar infarct
Pure motor or sensory deficit
- Hemorrhagic strokes are typically due to intracerebral hemorrhage or subarachnoid hemorrhage. The most common mechanism of intracerebral hemorrhage is hypertensive small-vessel disease, causing small lipohyalinotic aneurysms that rupture. Most subarachnoid hemorrhages are caused by rupture of saccular aneurysms.
Hemorrhagic Stroke Syndromes
Syndrome
Symptoms
Intracerebral hemorrhage
May be clinically indistinguishable from infarction; contralateral numbness and weakness; aphasia, neglect (depending on hemisphere); headache, vomiting, lethargy, marked hypertension more common
Cerebellar hemorrhage
Sudden onset of dizziness, vomiting, truncal instability, gaze palsies, stupor
[It is possible, although challenging, to clinically infer the location of the anatomic insult to the clinical presentation by correlating symptoms with circulatory region.
Anatomy of brain and blood flow. (Modified, with permission, from Schwartz DT. Emergency Radiology: Case Studies. New York, NY: McGraw-Hill Education, 2008: 505.)
For instance, aphasia usually corresponds to a left hemispheric stroke; neglect generally indicates a right hemispheric stroke; crossed signs (eg, right-sided facial droop with left-sided extremity weakness) typically indicate brainstem involvement.
Middle Cerebral Artery
Infarction of the cerebral cortex in the region of the brain supplied by the middle cerebral artery (MCA) or one of its branches is most commonly responsible for stroke.
It supplies the area of the cerebral cortex responsible for hand function; the anterior cerebral artery supplies the area responsible for lower extremity motion.
Cerebral artery circulation.
The typical clinical picture following MCA stroke is contralateral hemianesthesia (decreased sensation), homonymous hemianopia (visual field deficit), and spastic hemiplegia with more paralysis in the upper extremity than in the lower extremity. Because hand function requires relatively precise motor control, even for activities with assistive equipment, the prognosis for the functional use of the hand and arm is considerably worse than for the leg. Return of even gross motor control in the lower extremity may be sufficient for walking.
Infarction in the region of the anterior cerebral artery causes paralysis and sensory loss of the opposite lower limb and, to a lesser degree, the arm.
Stroke affecting the anterior artery has associated incontinence, leg weakness, and behavior problems; whereas stroke affecting the posterior cerebral artery has associated visual defects and alexia (the inability to understand written language).
Patients who have cerebral arteriosclerosis and suffer repeated bilateral infarctions are likely to have severe cognitive impairment that limits their general ability to function even when motor function is good.
After stroke, motor recovery follows a fairly typical pattern. The size of the lesion and the amount of collateral circulation determine the amount of permanent damage. Most recovery occurs within 6 months, although functional improvement may continue as the patient receives further sensorimotor reeducation and learns to cope with disability.
Initially after a stroke, the limbs are completely flaccid. Over the next few weeks, muscle tone and spasticity gradually increase in the adductor muscles of the shoulder and in the flexor muscles of the elbow, wrist, and fingers. Spasticity also develops in the lower extremity muscles. Most commonly, there is an extensor pattern of spasticity in the leg, characterized by hip adduction, knee extension, and equinovarus deformities of the foot and ankle.
Equinovarus deformities of the feet in a patient with spasticity.
In some cases, however, a flexion pattern of spasticity occurs, characterized by hip and knee flexion.
Whether the patient recovers the ability to move one joint independently of the others (selective movement) depends on the extent of the cerebral cortical damage. Dependence on the more neurologically primitive patterned movement (synergy) decreases as selective control improves. The extent to which motor impairment restricts function varies in the upper and lower extremities. Patterned movement is not functional in the upper extremity, but it may be useful in the lower extremity, where the patient uses the flexion synergy to advance the limb forward and the mass extension synergy for limb stability during standing.
The final processes in sensory perception occur in the cerebral cortex, where basic sensory information is integrated to complex sensory phenomena such as vision, proprioception, and perception of spatial relationships, shape, and texture. Patients with severe parietal dysfunction and sensory loss may lack sufficient perception of space and awareness of the involved segment of their body to ambulate. Patients with severe perceptual loss may lack balance to sit, stand, or walk. A visual field deficit further interferes with limb use and may cause patients to be unaware of their own limbs.
It is possible, although challenging, to clinically infer the location of the anatomic insult to the clinical presentation by correlating symptoms with circulatory region.
For instance, aphasia usually corresponds to a left hemispheric stroke; neglect generally indicates a right hemispheric stroke; crossed signs (eg, right-sided facial droop with left-sided extremity weakness) typically indicate brainstem involvement.1
Stroke is the fourth leading cause of death in the United States
Stroke is a serious and common disorder that affects over 795,000 persons in the United States each year. It remains the fourth leading cause of death in the United States after heart disease, cancer, and chronic lung disease.
Many surviving victims are left with neurologic deficits and may be unable to care for themselves. Symptoms vary widely depending on the type of infarct, the location, and the amount of brain involved.. Strokes are classified as either ischemic or hemorrhagic. Eighty percent of strokes are ischemic due to the blockage of a blood vessel secondary to thrombosis or embolism. They are generally seen in patients older than the age of 50 and present with the sudden onset of focal neurologic deficits. Hemorrhagic strokes are typically seen in younger patients and are due to intraparenchymal or subarachnoid cerebral vessel bleeding.
Strokes are more common in the elderly (75% occur in patients older than 75 years), males, and African Americans.
Symptoms vary widely depending on the type of infarct, the location, and the amount of brain involved (Tables 28–1 and 28–2). Strokes are classified as either ischemic or hemorrhagic. Eighty percent of strokes are ischemic due to the blockage of a blood vessel secondary to thrombosis or embolism. They are generally seen in patients older than the age of 50 and present with the sudden onset of focal neurologic deficits. Hemorrhagic strokes are typically seen in younger patients and are due to intraparenchymal or subarachnoid cerebral vessel bleeding.
Approximately 800,000 new strokes occur, as many as 30% of survivors permanently disabled and approximately 130,000 people die from stroke in the United States each year.
The incidence of stroke increases with age, The annual incidence of stroke is 1 in 1000, with cerebral thrombosis causing nearly three fourths of the cases. More than half of stroke victims survive and have an average life expectancy of approximately 6 years. Most survivors have the potential for significant function and useful lives if they receive the benefits of rehabilitation.
- The estimated global incidence of stroke is 2-3 per 1,000 person-years, with older patients and patients with carotid artery stenosis or atrial fibrillation most often affected.
- Risk factors for stroke include history of transient ischemic attack, hypertension, myocardial infarction, atrial fibrillation, left atrial enlargement, smoking, heavy alcohol use, diabetes, obesity, high cholesterol, and carotid artery stenosis.
Modifiable risk factors for stroke include systolic or diastolic hypertension, , and
- Address modifiable risk factors: Control HTN, high cholesterol, dyslipidemia, atrial fibrillation, diabetes, ; stop smoking; and maintain a healthy body weight. physical inactivity
- The United States Preventive Services Task Force (USPSTF) recommends the use of aspirin for women ages 55 to 79 when the potential benefit of reduction in ischemic strokes outweighs the potential harm of an increase in GI hemorrhage.11
- The USPSTK found the evidence insufficient to recommend for or against the use of aspirin for stroke reduction in men.11
Complications of Injecting Drug Use
- Local problems—Abscess (Figures 240-2
A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of Richard P. Usatine, MD.)
and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
- IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
- Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
- IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
- Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.
CTransient ischemic attack increases risk for 90-day stroke 10-fold.
Content 13
A 59-year-old man with a history of hypertension presents to the emergency department (ED) with right-sided paralysis and aphasia. The patient’s wife states he was in his normal state of health until 1 hour ago, when she heard a thud in the bathroom and walked in to find him collapsed on the floor. She immediately called emergency medical services, which transported the patient to your ED. En route, his fingerstick blood sugar was 108 mg/dL. On arrival in the ED, the patient is placed on monitors and an IV is established. His temperature is 36.8°C (98.2°F), blood pressure is 169/93 mm Hg, heart rate is 86 beats per minute, and respiratory rate is 20 breaths per minute. The patient has a noticeable left-gaze preference and is verbally unresponsive, although he will follow simple commands such as raising his left thumb. He has a normal neurologic examination on the left, but on the right he has a facial droop, no motor activity, decreased deep tendon reflexes (DTRs), and no sensation to light-touch.
Summary: This is a 59-year-old man with acute onset of aphasia and right-sided paralysis 60 minutes prior to arrival in the ED.
A 58-year-old man experienced a neurologic deficit and is diagnosed as having a stroke. Which of the following is the most likely etiology?
Next Question
You will be able to view all answers at the end of your quiz.
The correct answer is A. You answered A.
A. Ischemia is the most common etiology of stroke (due to thrombosis, embolism, or hypoperfusion) and is responsible for up to 80% of strokes.
Reference
https://www.ahajournals.org/doi/full/10.1161/STR.0000000000000158
Study Question
In a stroke affecting the territory of the middle cerebral artery–
Next Question
You will be able to view all answers at the end of your quiz.
USMLE Reviewer
For completeness the nonmodifiable risk factors are listed below:
-
Age
-
Gender
-
Family history
-
Ethnicity
-
Previous TIA or stroke
-
Diet, sodium, exercise, weight, smoking, alcohol intake
All patients should receive information and counseling about possible strategies to modify their lifestyle and risk factors.
Encourage a balanced diet
-
High in fresh fruits, vegetables, low-fat dairy products, dietary and soluble fiber, whole grains and proteins from plant sources, and low in saturated fats, cholesterol, and sodium.
-
Most Americans consume excessive amounts of sodium leading to increasing prevalence of hypertension.4
-
One teaspoon of salt contains approximately 2300 mg (the upper limit recommended).
-
Encourage exercise—there are many reasons to do this
-
A meta-analysis published by Lee et al5 reviewed 23 studies (18 cohort and 5 case control studies), examining the association between exercise and stroke incidence and mortality.
-
Highly active people were reported as having a 27% lower risk of stroke than people who were designated as low active.
-
Moderately active people also demonstrated a significantly reduced risk of stroke when compared to the low active group. The benefits of both high and moderate levels of activity were reported for both ischemic and hemorrhagic strokes.
Maintain healthy weight—goal BMI of 18.5 to 24.9 kg/m2.
Stop smoking
-
Smokers who smoke 20 or more cigarettes per day have 2 to 4 times the risk of stroke as compared to nonsmokers. This risk is dose-dependent so the more you smoke, the greater the risk of stroke. Heavy smokers are more at risk than light smokers. Light smokers are more at risk than nonsmokers. Stopping smoking has been shown to reverse risk of cardiovascular disease. This highlights the cessation of smoking as a leading effective intervention available to reduce risk of stroke.
Alcohol (in moderation)6
-
A meta-analysis by Reynolds et al4 revealed that individuals who consumed 1 to 2 drinks per day had the least risk of stroke and those that had more than 5 drinks per day had the most risk of stroke when compared to a group of abstainers. (J-shaped relationship as abstaining had a higher risk than 1-2 drinks/day, making the first part of the J.)
-
Heavy drinking (more than 5 drinks per day) was associated with the risk of hemorrhagic stroke.
-
Irregular and binge drinking (more than 5 drinks at one time) have been associated with an increased risk of hemorrhagic stroke.
A. The diagnosis in this patient is stroke, characterized by the sudden onset of focal neurologic deficits that persist for at least 24 hours owing to an abnormality of the cerebral circulation. The focal symptoms and signs that result from stroke correlate with the area of the brain supplied by the affected blood vessel. In this case, the patient has weakness and sensory loss on the right side. These symptoms suggest involvement of the left middle cerebral artery or at least its associated vascular territory. The vascular territory supplied by the middle cerebral artery includes the lateral frontal, parietal, lateral occipital, and anterior and superior temporal cortex and adjacent white matter, as well as the caudate, putamen, and internal capsule.
B. Risk factors for stroke include age, male sex, hypertension, hypercholesterolemia, diabetes, smoking, heavy alcoholconsumption, and oral contraceptive use.
C. Stroke is classified as either ischemic or hemorrhagic in origin. Ischemic stroke may result from the thrombotic or embolic occlusion of the vessel. Hemorrhagic stroke may result from intraparenchymal hemorrhage, subarachnoid hemorrhage, subdural hemorrhage, epidural hemorrhage, or hemorrhage within an ischemic infarction. Given the CT scan result, it is likely that this man has sustained an ischemic, rather than a hemorrhagic, stroke. Hemorrhagic and ischemic strokes can be difficult to differentiate on clinical grounds, but the former often produce a less predictable pattern of neurologic deficits. This is because the neurologic deficits in hemorrhagic stroke depend both on the location of the bleed and on factors that affect brain function at a distance from the hemorrhage, including increased intracranial pressure, edema, the compression of neighboring brain tissue, and rupture of blood into the ventricles or subarachnoid space.
D. The most likely underlying cause of stroke in this patient is atherosclerosis. Atherosclerosis arises from vascular endothelial cell injury, often caused by chronic hypertension or hypercholesterolemia, both present in this man. Endothelial injury stimulates the attachment of circulating monocytes and lymphocytes that migrate into the vessel wall and stimulate the proliferation of smooth muscle cells and fibroblasts. This results in plaque formation. Damaged endothelium also serves as a nidus of platelet aggregation that further stimulates the proliferation of smooth muscle and fibroblasts. The plaques formed may enlarge and occlude the vessel, leading to thrombotic stroke, or they may rupture, releasing emboli and causing embolic stroke.
History of TIA
History of previous stroke
hypertension,
atherosclerosis, cardiac disease (eg, atrial fibrillation, myocardial infarction, and valvular disease),
diabetes,
carotid stenosis,
dyslipidemia,
hypercoagulable states,
tobacco, and
alcohol use.
Stroke occurs when
thrombosis,
embolism, or hemorrhage interrupts cerebral oxygenation and causes the death of neurons in the brain.
This leads to deficits in cognition and in motor and sensory function.
- Strokes are generally classified as ischemic or hemorrhagic.
- Ischemic strokes are caused by large artery atherosclerosis (embolus or thrombosis), small vessel occlusion (lacunar), or cardioembolism (often from atrial fibrillation). Most strokes (85%) are ischemic, and 90% affect the middle cerebral artery
-
Ischemic Stroke SyndromesSyndrome Symptoms Dominant hemisphere Contralateral numbness and weakness, contralateral visual field cut, gaze preference, dysarthria, aphasia Nondominant hemisphere Contralateral numbness and weakness, visual field cut, contralateral neglect, dysarthria Anterior cerebral artery Contralateral weakness (leg > arm); mild sensory deficits; dyspraxia Middle cerebral artery Contralateral numbness and weakness (face, arm > leg); aphasia (if dominant hemisphere) Posterior cerebral artery Lack of visual recognition; altered mental status with impaired memory; cortical blindness Vertebrobasilar syndrome Dizziness, vertigo; diplopia; dysphagia; ataxia; ipsilateral cranial nerve palsies; contralateral weakness (crossed deficits) Basilar artery occlusion Quadriplegia; coma; locked-in syndrome (paralysis except upward gaze) Lacunar infarct Pure motor or sensory deficit - Hemorrhagic strokes are typically due to intracerebral hemorrhage or subarachnoid hemorrhage. The most common mechanism of intracerebral hemorrhage is hypertensive small-vessel disease, causing small lipohyalinotic aneurysms that rupture. Most subarachnoid hemorrhages are caused by rupture of saccular aneurysms.
Hemorrhagic Stroke SyndromesSyndrome Symptoms Intracerebral hemorrhage May be clinically indistinguishable from infarction; contralateral numbness and weakness; aphasia, neglect (depending on hemisphere); headache, vomiting, lethargy, marked hypertension more common Cerebellar hemorrhage Sudden onset of dizziness, vomiting, truncal instability, gaze palsies, stupor
[It is possible, although challenging, to clinically infer the location of the anatomic insult to the clinical presentation by correlating symptoms with circulatory region.
Anatomy of brain and blood flow. (Modified, with permission, from Schwartz DT. Emergency Radiology: Case Studies. New York, NY: McGraw-Hill Education, 2008: 505.)
For instance, aphasia usually corresponds to a left hemispheric stroke; neglect generally indicates a right hemispheric stroke; crossed signs (eg, right-sided facial droop with left-sided extremity weakness) typically indicate brainstem involvement.
Middle Cerebral Artery
Infarction of the cerebral cortex in the region of the brain supplied by the middle cerebral artery (MCA) or one of its branches is most commonly responsible for stroke.
It supplies the area of the cerebral cortex responsible for hand function; the anterior cerebral artery supplies the area responsible for lower extremity motion.
Cerebral artery circulation.
The typical clinical picture following MCA stroke is contralateral hemianesthesia (decreased sensation), homonymous hemianopia (visual field deficit), and spastic hemiplegia with more paralysis in the upper extremity than in the lower extremity. Because hand function requires relatively precise motor control, even for activities with assistive equipment, the prognosis for the functional use of the hand and arm is considerably worse than for the leg. Return of even gross motor control in the lower extremity may be sufficient for walking.
Infarction in the region of the anterior cerebral artery causes paralysis and sensory loss of the opposite lower limb and, to a lesser degree, the arm.
Patients who have cerebral arteriosclerosis and suffer repeated bilateral infarctions are likely to have severe cognitive impairment that limits their general ability to function even when motor function is good.
After stroke, motor recovery follows a fairly typical pattern. The size of the lesion and the amount of collateral circulation determine the amount of permanent damage. Most recovery occurs within 6 months, although functional improvement may continue as the patient receives further sensorimotor reeducation and learns to cope with disability.
Initially after a stroke, the limbs are completely flaccid. Over the next few weeks, muscle tone and spasticity gradually increase in the adductor muscles of the shoulder and in the flexor muscles of the elbow, wrist, and fingers. Spasticity also develops in the lower extremity muscles. Most commonly, there is an extensor pattern of spasticity in the leg, characterized by hip adduction, knee extension, and equinovarus deformities of the foot and ankle.
Equinovarus deformities of the feet in a patient with spasticity.
In some cases, however, a flexion pattern of spasticity occurs, characterized by hip and knee flexion.
Whether the patient recovers the ability to move one joint independently of the others (selective movement) depends on the extent of the cerebral cortical damage. Dependence on the more neurologically primitive patterned movement (synergy) decreases as selective control improves. The extent to which motor impairment restricts function varies in the upper and lower extremities. Patterned movement is not functional in the upper extremity, but it may be useful in the lower extremity, where the patient uses the flexion synergy to advance the limb forward and the mass extension synergy for limb stability during standing.
The final processes in sensory perception occur in the cerebral cortex, where basic sensory information is integrated to complex sensory phenomena such as vision, proprioception, and perception of spatial relationships, shape, and texture. Patients with severe parietal dysfunction and sensory loss may lack sufficient perception of space and awareness of the involved segment of their body to ambulate. Patients with severe perceptual loss may lack balance to sit, stand, or walk. A visual field deficit further interferes with limb use and may cause patients to be unaware of their own limbs.
It is possible, although challenging, to clinically infer the location of the anatomic insult to the clinical presentation by correlating symptoms with circulatory region.
For instance, aphasia usually corresponds to a left hemispheric stroke; neglect generally indicates a right hemispheric stroke; crossed signs (eg, right-sided facial droop with left-sided extremity weakness) typically indicate brainstem involvement.1
Stroke is the fourth leading cause of death in the United States
Stroke is a serious and common disorder that affects over 795,000 persons in the United States each year. It remains the fourth leading cause of death in the United States after heart disease, cancer, and chronic lung disease.
Many surviving victims are left with neurologic deficits and may be unable to care for themselves. Symptoms vary widely depending on the type of infarct, the location, and the amount of brain involved.. Strokes are classified as either ischemic or hemorrhagic. Eighty percent of strokes are ischemic due to the blockage of a blood vessel secondary to thrombosis or embolism. They are generally seen in patients older than the age of 50 and present with the sudden onset of focal neurologic deficits. Hemorrhagic strokes are typically seen in younger patients and are due to intraparenchymal or subarachnoid cerebral vessel bleeding.
Strokes are more common in the elderly (75% occur in patients older than 75 years), males, and African Americans.
Symptoms vary widely depending on the type of infarct, the location, and the amount of brain involved (Tables 28–1 and 28–2). Strokes are classified as either ischemic or hemorrhagic. Eighty percent of strokes are ischemic due to the blockage of a blood vessel secondary to thrombosis or embolism. They are generally seen in patients older than the age of 50 and present with the sudden onset of focal neurologic deficits. Hemorrhagic strokes are typically seen in younger patients and are due to intraparenchymal or subarachnoid cerebral vessel bleeding.
Approximately 800,000 new strokes occur, as many as 30% of survivors permanently disabled and approximately 130,000 people die from stroke in the United States each year.
The incidence of stroke increases with age, The annual incidence of stroke is 1 in 1000, with cerebral thrombosis causing nearly three fourths of the cases. More than half of stroke victims survive and have an average life expectancy of approximately 6 years. Most survivors have the potential for significant function and useful lives if they receive the benefits of rehabilitation.
- The estimated global incidence of stroke is 2-3 per 1,000 person-years, with older patients and patients with carotid artery stenosis or atrial fibrillation most often affected.
- Risk factors for stroke include history of transient ischemic attack, hypertension, myocardial infarction, atrial fibrillation, left atrial enlargement, smoking, heavy alcohol use, diabetes, obesity, high cholesterol, and carotid artery stenosis.
Modifiable risk factors for stroke include systolic or diastolic hypertension, , and
- Address modifiable risk factors: Control HTN, high cholesterol, dyslipidemia, atrial fibrillation, diabetes, ; stop smoking; and maintain a healthy body weight. physical inactivity
- The United States Preventive Services Task Force (USPSTF) recommends the use of aspirin for women ages 55 to 79 when the potential benefit of reduction in ischemic strokes outweighs the potential harm of an increase in GI hemorrhage.11
- The USPSTK found the evidence insufficient to recommend for or against the use of aspirin for stroke reduction in men.11
Complications of Injecting Drug Use
- Local problems—Abscess (Figures 240-2
and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of Richard P. Usatine, MD.)
- IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
- Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
- IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
- Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.
CTransient ischemic attack increases risk for 90-day stroke 10-fold.
Content 13
A 59-year-old man with a history of hypertension presents to the emergency department (ED) with right-sided paralysis and aphasia. The patient’s wife states he was in his normal state of health until 1 hour ago, when she heard a thud in the bathroom and walked in to find him collapsed on the floor. She immediately called emergency medical services, which transported the patient to your ED. En route, his fingerstick blood sugar was 108 mg/dL. On arrival in the ED, the patient is placed on monitors and an IV is established. His temperature is 36.8°C (98.2°F), blood pressure is 169/93 mm Hg, heart rate is 86 beats per minute, and respiratory rate is 20 breaths per minute. The patient has a noticeable left-gaze preference and is verbally unresponsive, although he will follow simple commands such as raising his left thumb. He has a normal neurologic examination on the left, but on the right he has a facial droop, no motor activity, decreased deep tendon reflexes (DTRs), and no sensation to light-touch.
Summary: This is a 59-year-old man with acute onset of aphasia and right-sided paralysis 60 minutes prior to arrival in the ED.
A 58-year-old man experienced a neurologic deficit and is diagnosed as having a stroke. Which of the following is the most likely etiology?
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The correct answer is A. You answered A.
A. Ischemia is the most common etiology of stroke (due to thrombosis, embolism, or hypoperfusion) and is responsible for up to 80% of strokes.
Reference
https://www.ahajournals.org/doi/full/10.1161/STR.0000000000000158
Study Question
In a stroke affecting the territory of the middle cerebral artery–
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