60 likes | 234 Views
AF: Issues with Anticoagulation. AFL: Anticoagulation like AF When undergoing procedures with risk for bleeding: May DC warfarin for up to one week without substituting heparin except for high risk pts. (Prosthetic valves, prior stroke or TIA). Class IIa (c)
E N D
AF:Issues with Anticoagulation • AFL: Anticoagulation like AF • When undergoing procedures with risk for bleeding: May DC warfarin for up to one week without substituting heparin except for high risk pts. (Prosthetic valves, prior stroke or TIA). Class IIa (c) • The use of low molecular heparin in AF has become common practice but it is based on extrapolation from DVT studies and from observational studies (no sufficient data)
AF:Issues with Cardioversion • AF duration unknown or over 48 hours: AC for 3 weeks before and one month after CV • Risk for strokes is same for chemical or electrical CV • TEE to rule out thrombus before CV is reasonable. (Class IIa, level of evidence A)
AF:Rate Control • 60 – 80 bpm at rest, 90 – 115 with moderate exercise. • AVN blocking agents (BB, CA channel blockers, Digoxin) • Digoxin reduces only resting heart rate and not during activity • Amiodarone can be used for rate control when others fail (severe LV dysfunction and CHF) • AV junction ablation and PPM only as a last resort
AF:Rhythm Control • Antiarrhythmic Drug therapy: • Class Ia (Quinidine, Procainamide) • Claa Ic (Flecainide, Propafenon) • Class III (Sotalol, Amiodarone, • Dofetilide) • Limited efficacy • Significant side effects • Pro-arrhythmic effects • Increase mortality • New AADs: Forget it ………
AF: Newer Class III AA Drugs Ibutilide Introduced in 1996. An injectable agent (1-2mg) Prolongs APD by enhancing a slow inward NA current 50% success in termination of acute AF (higher success rates for AFL May cause Torsades de Points in up to 8% of patients Dofetilide • Introduced in 1999. Oral agent. Prolongs APD by blocking Ikr. • More effective than low dose sotalol in restoring SR • Has neutral effect on mortality in HF and post MI patients. • Prolongs QT interval and may cause Torsades de Points in 3-5 % of patients (dose adjusted according to creatinine clearance)
AF:Rate vs. Rhythm Control Would a strategy of rhythm control results in: • Less ischemic strokes? • Improved symptoms? • Better quality of live? • Survival benefit?