atrial fibrillation warfarin and its newer alternatives dr mark abelson cardiologist somerset west
Post on 20-Jan-2016
214 Views
Preview:
TRANSCRIPT
Atrial Fibrillation Warfarin and its newer alternatives
Dr Mark Abelson
Cardiologist
Somerset West
MM00453 (01) Intl 06/09
Association of AF and Stroke
Occluded Left ICA-T Pre and Post Embolectomy
54y M, “Wake up” >4h,NIHSS=32 MRS=1 @ 90 d
Carotid Embolectomy
Atrial Fibrillation and Stroke
3 million in US and 4.5 million in the EU have AF
2/3 of AF population are at high-risk of stroke
AF is responsible for 15-20% of ischemic strokes
AF Incidence increases with age
AF and Stroke
-- 0.4% in general population -- 0.2% of 25-34 yrs of age -- 2-5% of >60 yrs of age -- 10% of > 80 yrs of age
Relationship of AF and Stroke
CHADS(2) Score CHADS
Congestive heart failure
+1
Hypertension +1
Age 75> +1
Diabetes Mellitus
+1
Stroke or History of Cerebral Ischemia
+2 0.8%2.2%
4.5%
8.6%
10.9%12.3%
13.7%
0.0%
5.0%
10.0%
15.0%
20.0%
0 1 2 3 4 5 6
F GAGE et al., 2004; 110:2287-2292
Annual Stroke Risk for Patients with AFBy CHADS(2) Score
Risk Stratification and Annual Stroke Risk for Patients with AF
Medical Management: Anticoagulant Effective: 67% stoke risk reduction(1)
Narrow therapeutic window for proper dose Contraindicated in 14-47% of patients at risk of stroke (2)
Major complication: bleeding
Surgical Excision (Appendectomy) Residual shunt: 10% (3) Inconsistent outcomes due to incomplete exclusion; Can create pouch with stagnant blood flow (4,5)
High invasiveness
Transcatheter Device Closure Minimally invasive nature Designed for percutaneous closure of the LAA in prevention of clot embolization that may form in the LAA Intended as an alternative to warfarin therapy for patients with non-valvular atrial fibrillation
Currently Available Management OptionsClot Prevention
Warfarin Therapeutic Window - INR of 2 to 3
A small window: difficult to achieve a well controlled therapeutic range
0 20 40 60 80 100
INR Control – Not Good
3000838-14
%%
Bungard: Pharmacotherapy 20:1060, 2001Bungard: Pharmacotherapy 20:1060, 2001
Low INR <1.6Low INR <1.6
TherapeuticTherapeuticINR 2-3INR 2-3
High INR >3.2High INR >3.2
Efficacy Efficacy 4-fold 4-fold
New Warfarin Alternatives
• NO INR monitoring- Dabigatran ( Pradaxa) – direct thrombin inhibitor
- Rivaroxaban (Xarelto) – F10a inhibitor
• Aspirin plus clopidogrel
• Aspirin (reduces stroke risk by 20%)
Risk of Stroke or Embolism
Connolly SJ et al. N Engl J Med 2009;361:1139-1151.
Can’t Take Warfarin??
• Frail, falls
• GI bleeds
• Cerebral bleeds
• Stroke despite therapeutic warfarin
• Non-compliant / labile INR
• (Do not want warfarin)
90% of clots in appendage
Currently available in limited markets
AMPLATZER® Cardiac Plug WATCHMAN®
Transcatheter Occlusion of the LAALeft Atrial Appendage Occluders
Protect AF – 21month F/U
Vergelegen Experience
• 7 patients – all elderly men with Chads>2• Significant GI bleeds on warfarin• Warfarin stopped – 2 had small strokes• One INR very labile due to recurrent UTI
(antibiotics. Suprapubic catheter)• All discharged next day – ASA and plavix for 1
month then ASA alone.
top related