Rohan Subasinghe

 Non valvular aF increases with age from 0.5 % at age to 9 % at age  AF is an independent Risk factor for CVA  Patients with AF have a 5 fold mean increase in Stroke due to atrial thrombosis.  Stroke mortality is higher in aptients with AF

 Aspirin - irreversibly blocks the formation of thromboxane A 2 in platelets, producing an inhibitory effect on platelet aggregationthromboxane A 2plateletsplatelet aggregation  Warfarin - Warfarin inhibits the vitamin K-dependent synthesis of biologically active forms of the calcium- dependent clotting factors II, VII, IX and Xvitamin KcalciumclottingIIVIIIXX  ximelagatran - direct thrombin inhibitor – less monitoring required but increased ALT levels

Risk stratification of patients –aspirin or warfarin? Possibility of intra and extra cranial haemorrhages. Interaction with other medications Disability, cognitive impairment, and problems with compliance are common in the elderly patients with AF Inconvenience of monitoring in warfarin therapy and impact on quality of life

 quickrefguide.pdf quickrefguide.pdf

 Numerous RCTs support tnromboprophylaxis in non valvular AF patients  Meta-analysis: Antithrombotic Therapy to Prevent Stroke in Patients Who Have Nonvalvular Atrial Fibrillation Robert G. Hart, MD; Lesly A. Pearce, MS; and Maria I. Aguilar, MD

 To characterize the efficacy and safety of antithrombotic agents for stroke prevention in patients who have atrial fibrillation  Adding 13 recent randomized trials to a previous meta-analysis.

 Double Blind Randomised trials  Mean follow-up of 3 months or longer that tested  Antithrombotic agents in patients who have nonvalvular atrial fibrillation.  Data Extraction: Two coauthors independently extracted information regarding interventions; participants; and occurrences of ischemic and hemorrhagic stroke, major extracranial bleeding, and death.

 Twenty-nine trials included participants  Mean age, 71 years; mean follow-up, 1.5 years).  Compared with the control, adjusted-dose warfarin (6 trials, 2900 participants) reduced stroke by 64% (95% CI, 49% to 74%) NNT 37 primary 12 secondary prev  Antiplatelet agents (8 trials, 4876 participants) reduced stroke by 22% (CI, 6% to 35%). NNT 125 / 40  Adjusted-dose warfarin was substantially more efficacious than antiplatelet therapy (relative risk reduction, 39% [CI, 22% to 52%]) (12 trials, participants). Heterogeneous NNT not calculable (estimated at 24)

 Other randomized comparisons were inconclusive.  Absolute increases in major extracranial haemorrhage were small (0.3% per year) on the basis of metaanalysis.  NNH for major haemorrhage 250  NNT for mortality benefit 200

CVAAFNon-AF 30-day Mortality23%8% 30-day recurrent CVA 1%4% Annual recurrent CVA 11%8.2%

 Bearing in mind that AF prevalence increases with age – is a mean age of 71 in the trials representative of patients we see?