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STROKE: Diagnostics and Treatments Module III. Initial stroke evaluation: Questions asked if initial Computed Tomography (CT) shows no hemorrhage. Where is the lesion? Cortical, sub-cortical, brainstem; right or left What vascular territory? Anterior, middle, posterior, watershed
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STROKE: Diagnostics and TreatmentsModule III K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Initial stroke evaluation: Questions asked if initial Computed Tomography (CT) shows no hemorrhage • Where is the lesion? • Cortical, sub-cortical, brainstem; right or left • What vascular territory? • Anterior, middle, posterior, watershed • Large or small vessel • What is the cause? • Embolic or other • What is the embolic source? • Heart, aorta, carotid or vertebral, intracranial arteries K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08) *TIA workup often mirrors that for ischemic stroke
Imaging the brain and the arteries • CT is good for initial evaluation to rule out hemorrhage and assess for size of stroke • Magnetic Resonance Imaging (MRI) is more sensitive • Imaging the arteries • Carotid ultrasound • Magnetic resonance angiography (MRA) • CT angiography (CTA) • Catheter arteriography • Tran-esophageal echocardiography (TEE) images heart and aorta K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
CT angiography (CTA) • CTA visualizes blood flow in arterial vessels serving the brain • CTA is less invasive and a more patient-friendly procedure than catheter angiography • Contrast material is injected into a small peripheral vein K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
CT Angiography: K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Magnetic Resonance Imaging (MRI): • Diffusion weighted images show all strokes from minutes to several weeks old • Helpful for all partial, anterior, posterior and lacunar syndromes • Magnetic resonance angiography usually completed if no CTA done K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
MRI: Different sequences of the same individual with acute ischemic infarct: T2 flair :evidence of small vessel disease in Sub-cortical & periventricular white matter Diffusion weighted: acute infarct in posterior limb of the internal capsule and insular cortex (lacunar stroke) K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
MRI: Left parietal infarct: K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Stroke Work Up: Labs • Complete blood count (CBC), Erythrocyte sedimentation rate (ESR), Prothrombin time (PT), Partial thromboplastin time (PTT), lipid profile • Younger patients: • Antiphospholipid antibodies, Leiden factor V, Protein C, S, Lupus anticoagulant, homocysteine (abnormalities indicate a hypercoaguable state) • Toxicology • Syphilis • Sickle cell • Family history of bleeding: • Thrombotic risk profile K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Seen on both TTE and TEE: Enlarged left atrium (> 40 mm) Akinetic segment Valve disease Dilating cardiomyopathy Seen only on TEE: Atrial septal defect, atrial septal aneurysm, patent foramen ovale Mural thrombus Aortic atheroma Work Up: Transthoracic echocardiogram (TTE) vs. Tran-esophageal (TEE) K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Stroke Treatment:Antiplatelets and Anticoagulants • Aspirin (ASA) is the gold standard • In selected cases, Plavix and Aggrenox are used • ASA is the bedrock of stroke prevention; reduces stroke risk by approximately 15% • Other Antiplatelet drugs are very expensive and offer little to no extra benefit K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Combination of Medications • Aspirin and Plavix often used after acute coronary events and coronary/carotid stenting and less commonly used after stroke • Aspirin and Warfarin are used in selected cases • Aggrenox (combination of aspirin and Dipyridamole) is sometimes used after stroke K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Treatment: Heparin Possible uses: • Suspected hypercoaguable states • Low blood flow states from significant large vessel stenosis • Arterial dissections • Cardiac embolic source, which has high risk of occurrence K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Treatment: Coumadin • Proven for cardiac embolic source in • Atrial fibrillation But commonly used for • Left ventricular thrombus • Dilated cardiomyopathy • Recent myocardial infarction (MI) • Unproven if no embolic source found • Unproven for minor embolic risk factors • Patent foramen ovale (PFO), Atrial septal aneurysm (ASA), aortic thrombi K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Contraindications: For Heparin and Coumadin • Recent gastrointestinal bleed • Recent intracerebral hemorrhage • Vitamin K deficiency • Abnormal platelet levels • Frequent falls • Sometimes age K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Contraindications:For Antiplatelet Medications • Active bleeding • Gastrointestinal lesions (ulcers) • Recent intracerebral hemorrhage • Allergy/sensitivity to drug • Caution with liver and kidney impairment K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Treatment: Carotid Endarterectomy • A surgical procedure in which atherosclerotic deposits are removed from one of the carotid arteries • Definite: Symptomatic (TIA or minor stroke) and >70% carotid stenosis • Risk of stroke and benefit of surgery weighed • Indicators: multiple atherosclerotic risk factors, symptomatic ischemia, high grade stenosis and hospital morbidity/mortality rate <6% http://my.mmc.org/C10/VascularCenter/default.aspx K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Stenting and Balloon Angioplasty Carotid and vertebral arteries are candidates • Micro-catheters and devices such as balloons, platinum coils, liquid adhesive, and stents are used; the interventional radiologist navigates from the femoral artery or vein to treat the abnormal target vessels • Assisted by real-time, bi-plane digital-subtraction angiography and real-time fluoroscopy K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Carotid Stenosis: Stent Placement and Balloon Angioplasty K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
New Interventions for Clot Removal: Merci Retrieval • Merci retrieval: Uses angiography and femoral approach is the most common • The Merci Balloon is maneuvered up to the carotid artery in the neck • A guide wire and the micro-catheter are placed just beyond the clot and the retriever device is deployed to engage and ensnare the clot • Once the clot is captured, a balloon guide catheter is inflated to temporarily arrest forward flow while the clot is being withdrawn • The clot is then pulled into the balloon guide catheter and completely out of the body. The balloon is then deflated, and blood flow is restored. K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Test questions: • Strokes caused by cardio-embolism often occur as a result of atrial fibrillation. Mr. CJ has this heart rhythm. The rate is controlled with a beta blocker. The cardiologist and neurologist agree that he also needs this medication to prevent another stroke: • Aspirin and Plavix • Warfarin (Coumadin) • Cardiazem • Aggrenox K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)
Test questions: 2. Which one of the following groups of patients who have had symptoms due to carotid stenosis is most likely to benefit from carotid Endarterectomy? • Patients with 30% or less stenosis • Patients with 30%–49% stenosis • Patients with 50%–69% stenosis • Patients with 70% or more stenosis, without near occlusion K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD3 (rev. 01.18.08)