Neuro3: Stroke (Dr. Greminger - 1.5 hrs)
What if the patient had a Transient Ischemic Attack (TIA) and not a stroke as our patient had?
(Would still do admission and work up for cause of CVA - more likely to have a subsequent episode in near future if underlying problem is not addressed, and it could be much worse) Among 488 patients with first TIAs from 2002 to 2007, the risk for stroke was 1.2% within 6 hours, 2.0% within 12 hours, and 5.1% within 24 hours. Of the 59 strokes that occurred within 30 days after TIA, 25 (42%) occurred within the first 24 hours.
What kinds of things cause Intracranial hemorrhage?
***Most often from high blood pressure.*** Aged blood vessels can also become more fragile. AVMs (cluster of abnormally formed blood vessels) may also predispose. Trauma?
Which way to image a stroke?
*CT* -CT - sensitivity increases after 24 hours for stroke, but may still see signs at < 6 hours -So CT can be negative initially, even if patient is having a stroke - not as sensitive for early ischemic stroke -Faster test - seconds as compared to minutes, good at picking up blood (CT scan is better as a quick screen for hemorrhagic vs non hemorrhagic - very fast test.) -Widely available *MRI* -May be contraindicated - ie pacer. -More expensive, sometimes less available in rural areas -Takes minutes to do (15-20) -DWI - Diffusion Weighted Images - based upon capacity of MRI to detect signal r/t water movement - can detect ischemia within 3-30 minutes of onset (brain cells may swell, changing ratio of intracellular to extracellular volume fractions) -Can also combine with MRA - which will help define blood vessels.
Can you give TPA to the woman in our case?
*Window*: Alteplase IV r-tPA is given through an IV in the arm, also known tPA, and works by dissolving the clot and improving blood flow to the part of the brain being deprived of blood flow. Alteplase IV r-tPA needs to be used within *three hours* of having a stroke or up to *4.5 hours* in certain eligible patients. *Contraindications*: -Intracranial hemorrhage, concern for SAH (Subarachnoid hemorrhage) -BP > 185/110 mm Hg -Rapidly resolving symptoms -MI, Stroke, head injury within past 3 mo -GIB within past 3 weeks -Major surgery within past 2 wks -Active bleeding, acute trauma, eg fracture -Anticoagulation therapy
We decided that are patient's stroke is most likely a thrombotic CVA...What risk factors did this patient have for this disease?
-HTN - goal < 140/90 -DM - goal HgbA1c < 7 -Lipids - goal appropriate dose of a statin -Sympathomimetic abuse - goal abstinence -Smoking - goal = cessation -Etoh - goal < 2/day men, < 1/day women -Obesity - goal waist < 40 in/men, < 35 in/women -Physical inactivity - goal > 30 min/day -Afib - anticoagulation (dabigatran, rivaroxaban, apixaban, coumadin) -ASA - goal daily use if *Framingham risk* > 6% *Risk factor modification is KEY!*
In concerns to our patient, She was given Alteplase intravenous tPA at 2 hours from symptom onset and transferred to a comprehensive stroke center, where digital subtraction angiography confirmed left middle cerebral artery occlusion (Figures 3 and 4). She underwent mechanical thrombectomy with recanalization of the MCA (Figure 5). What is her In hospital Management?
Aspirin started within 24-48 hours Let BP be initially 'high ish', but not too high. Consider swallow evaluation Good glucose control Look for underlying cause of stroke - this could mean carotid ultrasound to look for plaque (if > 70% stenosis with related CVA, may benefit from endarterectomy), MRA or angiogram to evaluate vasculature, heart monitoring to look for A fib, potential echocardiogram to look for pfo, potential for thrombotic work up in younger patients, etc.
Case: A 62 year old woman with presented to a primary stroke center with sudden onset of weakness of the right side. Symptoms started at 10 AM, family called 911, and it is now 11 AM. On examination, she has a global aphasia, left gaze preference, right homonymous hemianopsia (field cut), right facial droop, dysarthria, and right hemiplegia (NIH Stroke Scale = 22). PMH is significant for Hypertension, hyperlipidemia She is currently a smoker, and has been for the last 40 years or so. No history of trauma Not currently taking any anticoagulant medication
CVA What is the differential Diagnosis? -Migraine aura (extra effects)a -Syncope -Seizure -Metabolic encephalopathy (hypoglycemia, hepatic, renal, etc ) -MS - transient sx? -Psychiatric -Other brain disorders - mass lesion (abscess or tumor), etc. -Stroke (ischemic or hemorrhagic)
How do you manage a hemorrhagic stroke?
Control BP if too high Reverse AC if indicated Monitor Expectantly Hemorrhagic CVAs tend to have more complications. Patients can decompensate rapidly.
What if the patient came in 8-9 hours after a thrombotic CVA?
Could *not* give TPA, stroke team would still evaluate
An 84 year old male comes into the ER complaining of new onset neurologic symptoms which he noticed on waking up this morning. I is now 10 am, he went to bed at 8 pm. He is unable to move his right side, and has decreased sensation there. Both eyes deviates toward the left side. PERRLA. He has an expressive aphasia. PMH is significant for chronic HTN. He is taking HCTZ and aspirin. What is the differential diagnosis? What should we do first? Where might the lesion be?
Due to non-contrast CT, This stroke is in the LEFT PUTAMEN ICH is one form of bleeding
Back to the patient . . . What to do first in a stroke Patient?
Ensure Stability (ABC) = Airway, Breathing, and Circulation. Must assess and stabilize patient BEFORE any imaging H/P - Timing in particular is important - it will determine eligibility for thrombolysis or endovascular thrombectomy if ischemic Neurologic exam: facial paresis, arm drift/weakness, and abnormal speech are most predictive of diagnosis of acute stroke Urgent brain imaging with CT or MRI is needed with sudden neurologic deterioriation Labs to consider: -Urgent: imaging, finger stick glucose, O2 sat -Immediate to consider (may not get all if very convinced stroke): EKG, CBC with platelets, cardiac enzymes, BMP, INR, aPTT -For Selected Patients: LFTs (liver function test), Tox screen, BAL, Pregnancy test, ABG (arterial blood gas), CXR, LP, EEG, TT
Lacunar Stroke (Small Vessel)
HTN-induced endothelial damage Increased risk of bleeding with HTN Endothelial damage leads to clot formation Subtypes (there are more, but wanted to stress) Pure motor (IC) Pure Sensory (Thalamus) The lenticulostriate arteries branch off the middle cerebral artery to supply the deep structures of the brain. One of the hallmarks of a lacunar stroke is the lack of cortical signs. Lacunar stroke patients generally do not experience aphasia, neglect or visual field cuts. Depending on which vessels are occluded, there are multiple lacunar stroke syndromes. Two are worth further mention here. The most common is a pure motor stroke. Infarction of the posterior limb of the internal capsule will result in a pure motor stroke, in which patients experience hemiparesis of the legs, arms & face on one side due to disruption of the descending corticospinal and corticobulbar tracts. The other lacunar stroke symptoms I'll mention today is a pure sensory stroke. Infarction of the lateral thalamus results in a pure sensory stroke, in which patients experience numbness of the legs, arms & face on the contralateral side of the body.
Once you image a Stroke, what's the next step???
Head CT showed only equivocal hypodensity in the left middle cerebral artery territory (Figure 1 on previous slide). CT angiography showed a left middle cerebral artery occlusion (Figure 2 on previous slide, arrow). Next Step... -TPA (attached image)
Anterior Circulation Stroke
In general, strokes of the anterior circulation produce weakness & sensory deficits on the opposite side due to crossing of the motor and sensory tracts.
Risk Factors for Hemorrhagic Stroke
Incidence: 24.6 per 100,000 person-years Risk factors: increasing age Male HTN EtOH Tobacco Diabetes
Neuroanatomy of Stroke
Ischemic Strokes can be further defined by neuroanatomy: Large vessel A) Anterior circulation -Common carotid > MCA and ACA B) Posterior circulation -Vertebral artery > basilar artery Small vessel -Penetrating arteries (lacunar stroke)
Large Vessels Strokes
Large-vessel strokes involve the anterior or posterior cerebral circulation. Anteriorly, the common carotid arteries branch into the middle cerebral and anterior cerebral arteries. Posteriorly, the vertebral arteries flow into the basilar artery and supply the posterior cerebral circulation.
Anterior Circulation Stroke continued
Look at the relationship between the vascular distribution of the MCA and ACA and the homunculi shown here. This relationship explains the common findings of stroke. The middle cerebral artery supplies the lateral side of frontal, parietal and temporal lobes; With a middle cerebral artery stroke, the face & arms are affected more than the legs. Patients often experience a homonymous hemianopsia with ipsilateral gaze deviation. In lay terms, patient's are "looking at their lesion!". Strokes of the dominant cerebral hemisphere, typically the left side, will produce an aphasia, or problems speaking. Strokes of the nondominant hemisphere often result in contralateral hemineglect. A stroke of the anterior cerebral artery is more likely to affect the legs and is associated with frontal lobe problems, such as personality changes. ACA strokes are relatively rare. Also remember that one of the 1st branches off the ICA is the ophthalmic artery. Occlusion of the ophthalmic artery can cause amurosis fugax or blindness in one eye. Patients sometimes describe a shade being drawn down over the eye.
What kinds of things cause Ischemia?
Most commonly secondary to atherosclerotic (hardening and narrowing of the arteries) disease Substance abuse (causes vasospasm), pregnancy (thrombotic state), thrombophilias, vasculitis, endocarditis, cervical artery dissection, sickle cell disease, cerebral venous thrombosis, or paradoxical embolism can also be associated with CVA - though these are less typical, they are more common causes in YOUNG stroke patients.
Classic Patient CT scans of Ischemic Stroke
Notice the darker regions on the left image and in the right image you notice a aterioriole block of the left middle cerebral artery (Mike Called it...) CT scan is important to differentiate hemorrhagic from ischemic stroke - this is important, because treatment is very different!
Further Imaging of Ischemic Stroke
Our stroke teams are vital! Stroke (and heart attacks) are very time sensitive - the longer tissue goes without oxygen, the worse the prognosis. People will measure door time to CT scan, door time to TPA, door time to intervention, etc. That is why we always recommend ambulance to patients if this happens - just like a heart attack.
Common Presentations of Intracerebral Bleeding/ Hemorrhagic Stroke
Putamen - contralateral hemiparesis, gaze paresis and aphasia or hemineglect Thalamus - contralateral hemianesthesia Cerebellum - vomiting, ataxia, nystagmus, facial paralysis, ipsi gaze palsies and decreased LOC Pons - coma, quadriplegia, pinpoint pupils, autonomic instability The symptoms of intracerebral bleeding depend on the location of the hemorrhage. Half of intracerebral hemorrhages result from bleeding of the lenticulostriate branches of middle cerebral artery into the putamen. Putaminal bleeding manifests as contralateral hemiparesis, gaze paresis, and aphasia or hemineglect. Thalamic bleeding manifests as contralateral hemianesthesia. Cerebellar bleeding typically manifests as a depressed level of consciousness, vomiting, ataxia, nystagmus, facial paralysis, and ipsilateral gaze palsies. Pontine bleeding usually manifests as coma, quadriplegia, pinpoint pupils, and autonomic instability. While most strokes produce focal deficits, it is worth noting that Large ICHs will increase intracranial pressure and can result in a depressed level of consciousness
Basic Terms
Stroke CVA (Cerebrovascular Accident) TIA (Transient Ischemic Attack ) Apoplexy
How common is a stroke?
Stroke is the third leading cause of death in the United States. More than 140,000 people die each year from stroke in the United States. Stroke is the leading cause of serious, long-term disability in the United States. Each year, approximately 795,000 people suffer a stroke. About 600,000 of these are first attacks, and 185,000 are recurrent attacks. Nearly three-quarters of all strokes occur in people over the age of 65. The risk of having a stroke more than doubles each decade after the age of 55.
Supplemental Articles that could be testable...
Subacute management of ischemic stroke: -https://www.aafp.org/afp/2011/1215/p1383.html Diagnosis of Acute Stroke:https: -//www.aafp.org/afp/2015/0415/p528.html
Posterior Circulation
The posterior cerebral artery (PCA) supplies the occipital lobes. Patients with PCA infarcts typically present with a homonymous hemianopsia of the contralateral vision field. The picture here shows how Paris might look to a person with a left posterior cerebral artery stroke that caused a right homonymous hemianopsia; Because the left side of the brain caries the visual information for the right hemifields of each eye, this patient cannot see the right half of each visual field. These patients often have macular sparing and may also have difficulty naming colors. PCA infarcts of the nondominant hemisphere may result in neglect of the affected vision field. PCA infarcts often are less obvious to patients and their physicians than anterior circulation strokes or vertebrobasilar strokes.
Posterior Circulation Stroke
Vertebrobasilar disease accounts for about 20% of all ischemic strokes. The vertebral artery supplies the inferior cerebellum and lateral medulla. Cerebellar strokes cause cerebellar dysfunction with symptoms of vertigo, blurred vision, vomiting, nystagmus, ataxia, & postural instability. Patients with a lateral medullary infarct develop Wallenberg syndrome. They have crossed symptoms, for example numbness on the right side of the face and left side of the body due to damage to the cranial nerves on the ipsilateral side and damage to the sensory fibers above where they cross from the contralateral side. The basilar artery supplies primarily the rostral brainstem & occipital lobes. Basilar artery stroke thus causes cranial nerve palsies, which may result in gaze problems, hemianopsia, & miosis. More extensive basilar occlusions can cause more severe deficits and damage the reticular activating system leading to altered levels of consciousness as well as damage other cranial nerves. A basilar artery stroke is one of the few types of ischemic stroke that can cause loss of consciousness. Basilar artery occlusions have a poor prognosis, with mortality rates as high as 90%
What's it called when physicians never figure out what causes a stroke? How is it treated for there on out?
This happens about 20% of the time and is called cryptogenic stroke. risk factor modifications.
Etiology of Ischemic Stroke
When it's not atherosclerosis . . . .(it most commonly is atherosclerosis in elderly people)