Week 7 – Arterial and Venous Thrombolysis

1. Week 7 – Arterial and Venous Thrombolysis

2. Week 7 Objectives • Week 7 – Arterial and Venous Thrombolysis • Discuss CVA and TIA • Identify different types of Stroke • Know Signs and Symptoms of a Stroke • Know indications and contraindications for Stroke • Discuss basic set-up for Stroke Intervention • Discuss Thrombolytic Drugs • Identify other methods of Intervention for Strokes • Discuss thrombolysis for dural sinus thrombosis

3. Thrombolysis Defined • Thrombolysis is a defined as “the process of breaking up and dissolving blood clots.” • We will begin with the arterial thrombolysis and the treatment of patients that have suffered from a stroke.

4. Neuroradiology: Stroke Interventions “Time is Brain!”

5. Stroke Interventions • You will often hear the phrase “Time is brain!” • Once a vessel is occluded by either a clot or other debris, brain ischemia begins immediately. • Time is brain and the clock is ticking.

6. Stroke Interventions • What is a Stroke? “Stroke is a cardiovascular disease. It affects the arteries leading to and within the brain. A stroke occurs when a blood vessel that brings oxygen and nutrients to the brain bursts or is clogged by a blood clot or some other particle.”

7. Terminology of Strokes • CVA –Cerebrovascular Accident • Brain Attack • TIA- Transient Ischemic Attack • SAH-Subarachnoid Hemorrhage • ICH- Intracranial Hemorrhage • Infarct

8. Stroke/Infarction Statistics • Every 45 seconds, someone in America has a stroke. About 700,000 Americans will have a stroke this year. Stroke is our nation's No. 3 killer and a leading cause of severe, long-term disability. • Stroke kills nearly 273,000 people/year • In 2006, the estimated direct and indirect cost of stroke is $57.9 billion. • 50 percent had one-sided paralysis • 30 percent were unable to walk without some assistance

9. Stroke/Infarction Statistics(continued) • 26 percent were dependent in activities of daily living (grooming, eating, bathing, etc.) • 19 percent had aphasia (trouble speaking or understanding the speech of others) • 35 percent had depressive symptoms • 26 percent were institutionalized in a nursing home • from the American Stroke Association a division of the American Heart Association

10. Causes of Stroke: • Complications of several disorders • Atherosclerosis – most common. • Hypertension, smoking, diabetes. • Heart disease – Atrial fibrillation. • Other: • Trauma – fat embolism • Tumor, Infection • Caissons disease – The Bends (ex: Scuba Divers can suffer from Decompression sickness)

11. Types of Strokes • Ischemic- vessel clogs within (accounts for 83% of all cases) • Hemorrhagic- vessel ruptures causing blood to leak into the brain (17% of all cases) • TIAs (Transient Ischemic Attacks)-temporary minor or warning signs

13. Types of Strokes: Ischemic Strokes • Underlying condition to the obstruction of the vessel is atherosclerosis. • These fatty deposits (atherosclerosis) can lead to two types of obstruction: 1. Cerebral thrombosis 2. Cerebral embolism (ie, A-Fib)

15. Ischemic Strokes

16. Ischemic Strokes Watershed Area Watershed Area

17. Ischemic Strokes

18. Ischemic Strokes: Embolism formation

19. Ischemic Strokes: Local infarction Cell death ~ 6min central infarct area or umbra, surrounded by a penumbra of ischemic tissue that may recover

20. Ischemic penumbra:

21. Ischemic Strokes:Infarct Pathogenesis • Reduced blood supply – hypoxia/anoxia. • Altered metabolism  Na/K pump block. • Glutamate receptor act.  calcium influx. • 1-6 min – ischemic injury – vacuolation. • >6 min – cell death.

22. Infarct Stages: • Immediate – 6 hours • No Change both gross & micro • Acute stage – 2 days • Edema, loss of grey/white matter border. • Inflammation, Red neurons, neutrophils • Intermediate stage – 2 weeks. • Demarcation, soft friable tissue, cysts • Macrophages, liquifactive necrosis • Late stage – After 4 weeks. • Fluid filled cysts with dark grey margin (gliosis) • Removal of tissue by macrophages • Gliosis – proliferation of glia, loss of architecture.

23. Cerebral edema

24. Edema, loss of demarcation:

25. Cerebral Infarct - 1 Week

26. Cerebral Infarct - 2 Weeks

27. Infarct with Punctate hemorrhage

28. Cerebral Infarction - Late

29. Types of Strokes: Hemorrhagic Strokes • Two types of hemorrhagic strokes: 1. Intracranial Hemorrhage/ICH(usually caused by Aneurysm’s or AVMs) 2. Subarachnoid Hemorrhage/SAH

30. Intracranial Hemorrhage: • TRAUMA: • Epidural • Subdural • VASCULAR & TRAUMA • Intracerebral • Subarachnoid • Mixed cerebral-subarachnoid • Intracerebral - Hypertension • Subarachnoid - Berry aneurysm + HTN • Mixed cerebral – Vascular malformations.

32. Hypertensive CVD • Massive Intracerebral Hemorrhage • Ganglionic & Lobar hemorrhages • Putamen(60%), thalamus, ventricles. • Slit hemorrhages. • Microhemorrhages heal as slit spaces. • Lacunar infarcts • Brain stem pale infarcts – arteriolar sclerosis • Hypertensive encephalopathy • Headache, confusion, vomiting – raised ICP.

33. Subarachnoid Hemorrhage (SAH): Circle of Willis

34. Ruptured Berry Aneurysm

36. Intraventricular Hemorrhage:

37. Cerebral Infarction hemorrhage

38. Cerebral Infarction hemorrhage

39. Lacunar Infarct in pons

40. Types of Strokes:Transient Ischemic Attacks (TIAs) • Warning Signs for Possible Stroke • Temporary Effects, gradually resolve

41. TIAs: What are they? • A Transient Ischemic Attack (TIA) is a brief episode in which neurologic deficits suddenly occur, but then disappear completely • Most TIAs last a few minutes to an hour. • No neurologic deficits remain once a TIA has ended, because little or no brain tissue is permanently damaged. • A TIA is an indicator that the stage is set for an ischemic stroke. • Treatment of patients with TIAs can significantly reduce their risk of having a stroke.

42. TIAs: Carotid Territory Transient monocular blindness (TMB) TMB (also known as amaurosis fugax) occurs when the retina becomes temporarily ischemic. • Patients commonly describe a gray or black fog • or a mist clouding vision in all or part of one eye. • Attacks are typically brief (1-5 minutes), and • afterwards vision is fully restored. • TMB often signals the presence of severe • ipsilateral carotid artery disease in older adults. • TMB can also be caused by migraine.

43. TMB: What causes it? • Two Ideas: • 1. Thrombus from ulcerated atherosclerotic plaque at the origin of the internal carotid artery enters ophthalmic artery and plugs retinal vessel. • A small embolic particle can produce retinal ischemia • or block the central retinal artery. • If the embolus (often a platelet-fibrin aggregate) falls • apart, blood flow is restored and and vision returns. • 2. Low perfusion in the internal carotid artery, putting distal structures like the retina at risk. • This mechanism implies presence of severe carotid • stenosis that significantly impairs blood flow.

44. TIAs: Carotid Territory Transient hemispheric attacks Problems typically produced • One-sided limb weakness, clumsiness or paralysis • One-sided numbness, paresthesia, or sensory loss • Difficulty with language production or • comprehension • Inability to articulate words clearly, often • described as ‘I slurred my words’ (dysarthria) • Partial or complete homonymous visual field • defects (patients seldom describe these)

45. Carotid Bifurcation atherosclerotic plaque and thrombus Thrombus on plaque surface Plaque Thrombus on plaque surface Plaque reduces the diameter of artery

46. TIAs: Vertebral-Basilar Various combinations may bepresent Problems typically produced • Vertigo or dizziness • Unilateral or bilateral weakness or clumsiness • Unilateral or bilateral numbness or sensory loss • Limb ataxia or coarse tremor, staggering gait • Dysarthria • Visual field defect, blindness, or diplopia • Nystagmus (‘it jumps around when I look at it’)

47. Patients may ignore TIAs! • Because the episode of impaired function is brief, patients may not tell you about it unless you ask. • Seniors with somewhat impaired memory may simply not recall such brief events. • TIAs in carotid territory predict severe atherosclerosis • in the proximal internal carotid artery. • Tests can determine actual blood flow in the carotid. • The odds of stroke in the next 1-2 weeks are great! • If severe narrowing is present, surgical and medical • treatments can help to reduce stroke risk.

48. Summary of Stroke Causes: • Stroke: Acute neurological deficit - Clinical • Cerebrovascular Accident – pathology. • Ischemic/Hemorrhagic • Thrombosis, Embolism/Hemorrhage • Atherosclerosis, Hypertension, Heart Disease. • Global – Systemic Hypoxia – Watershed infarct • Focal – Thrombosis, Embolism or Hemorrhage • Liquifaction necrosis  Cyst formation, gliosis. • Hypertension – Pale, Lacunar infarcts, slit hemorrhage

49. Non modifiable Age Male sex Race Heredity Modifiable Hypertension Diabetes Smoking Hyperlipidemia Excess Alcohol Heart disease (AF) Oral contraceptives Hypercoagulability. Risk factors of Strokes:

50. Signs and symptoms of Stroke • Sudden onset of: • numbness or weakness of the face, arm or leg, especially on one side of the body • confusion, trouble speaking or understanding • trouble seeing in one or both eyes • trouble walking, dizziness, loss of balance or coordination • severe headache with no known cause