Acute Ischemic Stroke: Introduction to Diagnosis and Treatment Charles Esenwa, MD Stroke Fellow, Neurology
Risk Factors Age Hypertension Atrial fibrillation Carotid stenosis Previous stroke Tobacco Diabetes Hypercholesterolemia Illicit drug use Hypercoagulable state
Blood Flow in Stroke Territory Cerebral tissues dysfunction relating to to 1) cerebral blood flow (CBF), 2) time from stroke onset and 3) distance from the core of the infarct. In the setting of an acute vascular occlusion, CBF in the vascular territory diminishes rapidly. The progression from ischemia to infarction is directly related to drop in CBF and the length of time the tissue is hypoperfused.
Types of stroke Figure 35-2 shows the Trial of Org10172 in Acute Stroke Treatment (TOAST) classification criteria for ischemic stroke and the estimated relative distribution of stroke within each category
Netter, Neuroanatomy
Middle Cerebral Artery Haines – Neuroanatomy
Large Vessel Stroke Syndromes Emergency Neurology: Acute Stroke Management. 2012
Inpatient vs Outpatient Work Up ???
Goals in Acute Hospital Care Time to Treatment Therapy revascularization rate complication rate practicality and cost Neuroprotection extending viability of penumbra limiting long term effects of ischemia Patient Selection stroke type collaterals and penumbra prognotic factors co-morbidities Goal
IV TPA exclusion Contraindications In patients that are considered for alteplase/rtPA within the 0-3 hour window, the following exclusions apply: Significant head trauma or prior stroke in previous 3 months Symptoms suggest subarachnoid hemorrhage Arterial puncture at non-compressible site in previous 7 days Intracranial malignant neoplasm, arteriovenous malformation, or aneurysm Recent intracranial or intraspinal surgery Elevated blood pressure (systolic > 185 mmHg or diastolic > 110 mmHg) that is unable to be controlled Active internal bleeding Acute bleeding diathesis, including but not limited to platelet count < 100,000/mm³ Heparin received within 48 hours resulting in abnormally elevated aPTT, greater than the upper limit of normal Current use of anticoagulant with INR > 1.7 or PT > 15 seconds Current use of direct thrombin inhibitors or direct factor Xa inhibitors with elevated sensitive laboratory tests (such as aPTT, INR, platelet count, and ECT; TT, or appropriate factor Xa activity assays.) With respect to the oral agents, may consider alteplase/rtPA if there is clear evidence that the patient meets all three criteria: 1. Normal renal function (creatinine clearance > 50 mL/min), 2. Has not taken dabigatran, rivaroxaban or apixaban for at least the past 48 hours, and
Evidence for IV-TPA NINDS, NEJM 1995: TPA within 3hours of symptoms onset no change on NIHSS at 24hrs but better functional outcome at 3 months (absolute 12%, relative 30%) ECASS3, NEJM 2008: TPA within 4.5 hours of symptom onset ARR = 13%, RR = 30% ARR = 7%, RR = 15%
Why Intra-arterial Thrombectomy Calgary stroke program (Bhatia, et al, 2010)2 Analyzed CT-A database from 2002-2009 for patients with proximal occlusions who received tPA (n=127) Only 27 patients (21.25%) recanalized 1/24 distal ICA (4.4%) 21/65 M1 occlusions (32.3%) 4/13 M2 occlusions (30.8%) 1/25 basilar occlusions (4%) Recanalization was strongest predictor of good outcome
Endovascular therapy Includes: Indicated for large vessel occlusion Mechanical thrombectomy Intra-arterial TPA (IA-TPA) Indicated for large vessel occlusion Up to 6 hours from symptom onset Can use those when IV-TPA is contraindicated No Very clear evidence for benefit over IV-TPA
Time to Treament Saver, Oct 2016
Post Emergency Room Management ALL Stroke Patients Examine and complete NIHSS Re-evaluate airway Dysphagia Screen Consider duatube Venodynes EKG, serial troponins, telemetry, TTE HgA1C, Lipids, TSH, ESR/CRP, RPR, Utox, UA, U culture TPA not administered BP goal <220/120 *Aspirin (PO or rectal) *Lovenox (heparin if GFR<30) for DVT ppx TPA administered prior to NICU arrival BP goal <180/105 x24 hours Repeat head CT 24 hours post-TPA *Contraindicated x24hrs after TPA dosing
Major Complications of Stroke Hemorrhagic conversion (2% without vs. 6% with TPA) Angioedema and anaphylaxis Cerebral Edema Myocardial infarction Respiratory failure Aspiration Pneumonia DVT/PE
Acute Stroke Case
Early Infarct Signs
ASPECTS SCORE 0-10 (10 being best)
Case Continued
Case Continued low CBV, prolonged MTT and decreased CBF, surrounded by a widespread area of tissue at risk; defined by relatively stable CBV, prolonged MTT and decreased CBF.
Case #2
Large Vessel Atherosclerosis
Case #3
Anti-platelet therapy
Case #4
Atrial Fibrillation
Clinical Cases Case 1 45 yo M with DM, HTN, HL and two previous strokes without residual deficit presents with acute dizziness, nausea/vomitting, diplopia and unsteadiness In the ED, NIHSS was 6 for weakness, ataxia and slurred speech
Case 1
Case 1: What are you worried about? How do you manage this case?
Case 2 53 yo M presented with sudden onset LOC. On exam he was unresponsive with extensor posturing throughout. Pupils were equal, oculocephalic reflex was absent, corneals were sluggish and he did not gag. NIHSS 30
Case 2: What is the syndrome What are the management issues? What could have been done to try to prevent this?
Case 3: 85 yo Woman with HTN and DMII, presented with acute aphasia and R sided weakness starting 20 minutes ago. NIHSS 17. Got IV-TPA within 1 hour of symptom onset.
Case 3: What is the syndrome? What is your BP goal? What do you worry about?
Case 3: On re-examination you note that her BP is 200/110 and NIHSS is now 24 Her nurse also tells you that she is concerned about her breathing. What do you to do next?
Case 3
Case 4: A 50 yo M presents with sudden onset L sided weakness and slurred speech. On examine she has a R gaze preference, neglects the L side and is not moving the left at all. NIHSS 20.
Case 4 What do you worry about?
MR angiogram
Case 4: Revisited What if he were fluctuating? Between NIHSS of 3 and NIHSS of 20 and has this scan?
Case 4: Revisited CT angiogram of the head
Case 4: Revisited MRI – DWI What can you do to further evaluate? How would you manage the blood pressure?
Trials
Trials