This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
• I perceive no conflicting interest but am open to negotiation
Antithrombotics in Stroke management
•Evidence and its relation to practice.
•Risk and benefit: finding the right balance.
2
How do clinicians feel about Evidence and Guidelines?
• Education events: Polling of physicians indicates that reviewing evidence is not desirable and does not contribute to changes in practice.
• Answer questions, make recommendations that actually make sense and are applicable to a persons practice.
• Trust me I’m an expert or
• Don’t trust me because I am an expert and I don’t take care of real patients in the real world
3
Experts: help with choice of drug and timing…
4
Things I know that you know
• Antithrombotics are effective in reducing stroke risk
• Antithrombotics are effective in treating stroke
• Antithrombotics can be dangerous
5
Stroke Treatment
Blood clots are bad: Stroke, MI, PE, DVT, limb ischemia, organ infarction
Antithrombotics are bad but less bad.
Timing is everything
Bauer KA. 2010; Turpie AG. 2007; Weitz JI. 2010.
Things I think you want to know
• What patients get thrombolytics, antiplatelet agents, anticoagulants?
• When should drugs be started and stopped?
• What agents are better? Medication choices
• What agents are riskier and when?
7
Things I think I know
• Difficult treatment decisions can’t be made with out knowing phenotype
• Size matters: Big stroke little stroke
• Timing is everything.
• Prevention is better than treating stroke
• NOACS/DOACS: no evidence of superiority of any agent, all significantly reduce risk of mortality, stroke, ICH vs VKA, no direct comparisons between agents…makes bleeding risks harder to evaluate. Patient Characteristics in ROCKET AF, RE-LY and ARISTOTLE...
8
Anticoagulation and VTE prophylaxis in Stroke
• Phenotype: essential for treating individuals not populations
• There is no reliable “recipe” because of phenotype
• Ethnicity: Asians (Slide 20)
• Chads2 Chads2 Vasc score,(risk) Has bled (bleed risk)
• ACS; Stent, AF, EF, vascular plaque
• Hs troponins are continuing to create opportunity and potential harm;
• BP control
• Renal status (eGFR, CrCl)
• Size of stroke: 3-6-9; 5-10-15
• ICH: trauma, no trauma, anticoagulation before; ICH expansion, hemorrhagic transformation
9
Things you should know
• What patients receive antiplatelet agents and when?
• What patients receive anticoagulants and when?
• What anticoagulants for what patient? VTE prophylaxis, stroke risk reduction, ACS, DVT/PE?
• Imaging results When decisions need to be made
• NOACS/DOACS: Are preferred in patients who have CrCl>50; probably preferred for CrCl 30-49.
• There is growing concern with underdosing of the NOACS/DOACS
10
Stroke Prevention in Patients with Atrial Fibrillation
Atrial Fibrillation (AF)
Currently, it is estimated that ~350,000 Canadians have atrial fibrillation (AF)1
AF affects approximately:
3% of Canadians over the age of 451
6% over the age of 651
10% over the age of 802,3
The lifetime risk of AF is 1 in 4 after the age of 404,5
1. Heart and Stroke Foundation. Atrial fibrillation. Available at http://www.heartandstroke.com/site/c.ikIQLcMWJtE/b.3483991/k.34A8/Statistics.htm.
2. Go AS, et al. JAMA. 2001;285:2370–5.
3. Heeringa J, et al. Eur Heart J. 2006;27:949–53.
4. Lloyd-Jones DM, et al. Circulation. 2002;106:3068-72.
5. Lloyd-Jones DM, et al. Circulation. 2004;110:1042-6.
Effect of first ischemic stroke in AF patients
13
Stroke severity and AF
14
AF consequences
Independent risk factor for stroke
Fivefold increased risk
One in six strokes occur in patients with AF
AF-related strokes are typically more severe than strokes due to other etiologies
Stroke risk persists even in patients with asymptomatic or intermittent AF
15
AF consequences
16
Independent risk factor for mortality
Twofold increased risk
Independent risk factor for heart failure
Heart failure further aggravates AF,
worsening overall prognosis
Guideline says:
17
*CCS footnote
OAC for most patients 65 years of age or older or those with Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack (CHADS2) score ≥ 1; acetylsalicylic acid (ASA) for patients younger than 65 years of age with CHADS2 = 0 with arterial vascular disease (coronary, aortic, or peripheral); and no antithrombotic therapy for patients younger than 65 years of age with CHADS2 = 0 and no arterial vascular disease. Bleeding risks should be modified when and if possible. The CCS also suggests that a novel direct oral anticoagulant (NOAC) be used in preference to warfarin for OAC therapy in nonvalvular AF patients.
Might require lower dosing.
18
Stroke Types and Incidence
Ischemic stroke 85-88%
Hemorrhagic stroke 12-15%
Other 5%
Cryptogenic 30%
Cardiogenic embolism
20%
Small vessel disease
“lacunes” 25%
Atherosclerotic cerebrovascular
disease 20%
19
• Ischemic stroke: ASA or Clopidogrel
• Hemiplegic stroke (large) VTE risk is high, hemorrhagic transformation usually occurs early (24-48 hours).
• Hemorrhagic stroke: VTE is OK within 48-72 hours but call someone.
• AF: anticoagulation timing depends on stroke size, first stroke, second stroke and all the phenotype questions.
• Big stroke: treat later (Generally 2 weeks). Call someone. timing
Timing issues non tPA; Stroke and VTE
20
Inadequate anticoagulation in high risk patients with atrial fibrillation (Registry of Canadian Stroke Network)
•Preadmission medications in patients with known atrial fibrillation who were admitted with acute ischemic stroke (N=597)