(third leading cause of death after heart disease and cancer)
Risk Factors: age, hypertension, diabetes (need tight glucose control), hyperlipidemia, smoking, cardiac disease, AFib, prior CVA or TIA, + family history, hyperhomocysteinemia, blood dotting disorders, drug abuse, male sex, African American, asymptomatic carotid bruit, inactive, obese, excess alcohol, apolipoprotein E4, factor V mutation
Pathophysiology:
Ischemic - 85% [cardiac embolism (AFib, acute MI, dilated cardiomypopathy, LV aneurysm, atrial myxoma, atrial septal aneurysm, rheumatic valve disease, endocarditis, prosthetic valves, patent foramen ovale - paradoxical via DVT), atherosclerotic embolism - large vessel, atherothrombotic large vessel disease (cartoid bifurcation, aortic arch, dissection), small vessel disease (lacunar, hypertension, diabetes, CADASIL, arteritis), cryptogenic, craniocervical arterial dissection, cerebral venous thrombosis, antiphospholipid antibody syndrome, cardiac or carotid surgery, hypercoaguable states (protein C or protein S deficiencies, activated protein C resistance, fibromuscular disease, lupus, vasculitis, migraine, polycythemia, sickle cell disease, TTP, syphilis, TB meningitis, mitochondrial disorders, homocystinuria, Fabry's disease, moyamoya disease];
Hemorrhagic 15% [intracerebral hemorrhage - ICH, subarachnoid hemorrhage - SAH]; Etiologies - hypertension, saccular aneurysms (most common locations - ant. communicating artery - post. communicating artery - bifurcation of the MCA terminus of the ICA; increased risk - polycystic kidney disease, fibromuscular dysplasia, moyamoya disease), AVM, cavernous angiomas, trauma, coagulopathy, drugs (anticoagulants, thrombolytics, cocaine, amphetamines), neoplasms, hemorrhagic infarct transformation, cerebral amyloid angiopathy, moyamoya diseases, vasculitits, mycotic aneurysms; Higher risk with African Americans, Hispanics, and Asians.
Warning Signs - Sudden weakness or paralysis (unilateral or bilateral), dysarthria, dizzy, loss of speech, severe headaches, altered mental status, loss of consciousness.
Clinical Presentation - Altered level of consciousness (coma, stupor, AMS, delirium, seizures, agitation), headache aphasia, dysarthria, facial weakness or asymmetry (can be ipsilateral or contralateral to limb weakness), incoordination, weakness, paralysis, altered sensation, ataxia, altered vision (visual loss, monocular, binocular, partial or full loss of field, double vision), nausea, vomiting, vertigo, photophobia, phonophobia.
Stroke Syndromes: Middle Cerebral Artery (Anterior circulation, frontal, partietal, temporal lobes, basil ganglia) - Left (dominant) hemisphere - aphasia, right hemiparesis, right hemihypesthesia, left gaze preference, right hemianopsia; Right (non dominant) hemisphere - left neglect, left hemiparesis, left hemihypesthesia, right gaze preference, left hemianopsia, confusion.
Anterior Cerebral Artery (Anterior circulation, paramedian frontal lobe) - contralateral lower extremity weakness and sensory loss, abulia (apathy, akinetic mutism).
Ophthalmic Artery - ipsilateral monocular visual loss.
Posterior Cerebral Artery (Occipital and mesial temporal lobes, thalamus) - contralateral homonymous hemianopsia or hemihypesthesia, memory loss.
Basilar Artery (Posterior circulation, brainstem, cerebellum unilateral or bilateral) - coma, visual field deficits, dysconjugate gaze, nystagmus, hemiparesis (contralateral), quadriparesis (locked in state - awake), crossed or bilateral sensory loss, limb ataxia (ipsilateral to lesion), gait ataxia, dysarthria, dysphagia, bilateral extremity weakness.
Posterior Inferior Cerebellar Artery (Posterior circulation, lateral medullary or Wallenberg syndrome) - Ipsilateral loss of pain and temperature sensation on the face, contralateral loss of pain and temperature sensation of the limbs, ipsilateral limb ataxia, gait ataxia, nystagmus, Horner syndrome (ipsilateral ptosis, miosis, anhydrosis), hoarseness, dysphagia.
Lacunar Syndrome - Pure motor stroke (internal capsule, corona radiata, pons), pure sensory stroke ((thalamus), ataxic hemiparesis (pons, internal capsule), clumsy hand - dysarthria (internal capsule, pons).
Differential Diagnosis - Craniofacial or cervical trauma, intracranial mass (tumor, subdural hematoma, epidural hematoma, abscess), meningitis, encephalitis, seizures, post ictal state, migraine, toxic metabolic pathology (hyperglycemia, hypoglycemia, DKA, narcotic or other drog OD, S/P cardiac arrest - ischemic insult, sepsis, hepatic encephalopathy, renal failure, hypercapnia), peripheral neuopathy, malingering, somatization, psychiatric.
Complicatons - Cerebral edema, hemorrhagic infarct conversion (esp. with anticoagulation or thrombolytics), recurrent stroke, seizures, vasospasm, hydrocephalus, MI, arrhythmias, aspiration pneumonia, atelectasis, pulmonary edema, pulmonary embolism, DVT, decubitus ulcer, UTI, GI bleed, depression, hypernatremia, hyponatremia
STAT Lab Evaluation (with Acute CVA) - CT of the brain without contrast, CBC, platelets, PT, aPTT, electrolytes, glucose, ECG, CXR, C spine (with coma or neck pain), ABG with ? Hypoxia, BUN, creatinine, LFTs, LP with ? SAH and negative head CT, EEG with ? Seizures.
Inclusion Criteria for tPA (Use with Acute Stroke) - Age >=18, clinical diagnosis of ischemic stroke with measureable neurological deficit after CT exludes intracranial hemorrhage, onset of symptoms < 3 hours before starting thrombolytics.
Exclusion Criteria for tPA (Use with ? Acute Stroke) - Onset of symptoms > 3 hours before able to give thrombolytics, intracranial hemorrhage on head CT, minor or rapidly improving symptoms, seizure with stroke, glucose < 50 mg/dl or >400 mg/dl, SBP > 185 mmHg or DBP > 110 mmHg with aggressive treatment, CVA or serious head trauma <= 3 months old, major surgery or serious trauma <= 2 weeks, GI or GU hemorrhage <= 3 weeks, ? subarachnoid hemorrhage (clinical suspicion), arterial puncture at a noncompressible site within one week, plately count < 100,000/mm^3, PT > 15 seconds when on oral anticoagulants, history of intracranial hemorrhage, LP within 7 days, lactating, pregnant, ? post MI pericarditis, receiving heparin with 48 hours with an elevated aPTT, hypodensity or mass effect on CT scan suggestive of evolving infarction, consider exclusion with known AVM or intracranial aneurysm.
Manag. of Suspected ICH (during tPA Administration) - Clinical Presentation - acute neurologic deterioration, new headache, acute hypertension, nausea or vomiting; Management - D/C tPA, obtain STAT CT of the head, draw labs (CBC, platelets, PT, aPTT, fibrinogen, type and cross), prepare 6-8 units of cryoprecipitate containing factor VIII, prepare 6-8 units of platelets, obtain hematology and neurosurgery consult