Atrial Fibrillation: New Guidelines and New Recommendations - PDF document

4/6/15 Atrial Fibrillation: New Guidelines and New Recommendations Katherine Julian, MD April 6, 2015 n No financial disclosures 1

4/6/15 Epidemiology n Most common arrhythmia in clinical practice n Projected prevalence of more than 10 million by the year 2050 n Accounts for 1/3 of all hospitalizations for cardiac rhythm disturbances n Increased prevalence with age: 8% in those older than 80 years Why Is This Important? n AF associated with an increased risk of stroke n Six-fold increase in rate of ischemic stroke n Rate of ischemic stroke in non-valvular AF approx 5%/year n AF accounts for 15% of all strokes n Associated with increased CHF and all-cause mortality n May be independently associated with MI Singer DE, et al. Chest, 2004;126. Soliman EZ, et al. JAMA Intern Med. 2014 2

4/6/15 Atrial Fibrillation n Work-Up n Rate vs. Rhythm Control n Treatment Options n Anti-coagulation n Future Treatment Options Case I n 55 yo woman being seen for a new patient visit. Asymptomatic. n PMH: HTN (untreated) n PE: 150/80, HR 125 Irregularly irregular 3

4/6/15 The EKG… What Work-Up Does She Need? n Complete history and physical n PIRATES 4

4/6/15 Secondary Causes of AF n PIRATES – secondary causes n Pericarditis n Pulmonary disease/pulmonary embolism n Ischemia n Rheumatic heart disease n Atrial myxoma n Thyrotoxicosis n Ethanol n Sepsis Secondary Causes of AF n Other Secondary Causes n Obesity – likely due to LA dilatation n ?Smoking n Familial n ?Inflammation n Treat Underlying Etiology 5

4/6/15 What Work-Up Does She Need? n Complete history and physical exam n Pulmonary disease/pulmonary embolism n Ischemia n Ethanol n Sepsis January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 What Work-Up Does She Need? n ECHO n LVH/LV size & function n Occult valvular disease n Occult pericardial disease January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 6

4/6/15 What Work-Up Does She Need? n Complete history and physical exam n TTE n EKG n Associated labs n TSH, renal and hepatic function n Other tests based on history…ex: event monitor January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 Classification n Recurrent: 2 or more episodes n Paroxysmal: arrhythmia terminates spontaneously or with treatment within 7 days of onset n Persistent: sustained beyond 7 days and is not self- terminating n Permanent: cardioversion has failed (or been foregone) n Lone: patients <60 years without clinical/EKG evidence of cardiopulmonary disease (incl htn) 7

4/6/15 Hemodynamic Consequences of AF n Loss of atrial mechanical function - fibrosis n Irregular ventricular response n Elevated HR n Results in: n Reduction in diastolic filling, stoke volume, CO n Risk of cardiomyopathy (chronic > 130 bpm) n Asymptomatic afib 12X more common… Rate or Rhythm? n AFFIRM Study n Randomized 4070 patients with AF, F/U 3.5 years n Rate-control = coumadin n Rhythm-control = cardioversion/meds/coumadin n No difference in survival, stroke or QOL n Trend towards increased survival in rate-control (P = .08) n Pts > 65 yrs and pts without h/o CHF had better outcomes with rate-control therapy n More thrombotic events in rhythm arm AFFIRM Investigators, NEJM, 2002;347 8

4/6/15 Rate or Rhythm? n AFFIRM Study…the Caveats… n No symptomatic patients n Average age of enrollees: 70 yrs n Only 63% of patients in control arm in sinus rhythm AFFIRM Investigators, NEJM, 2002;347 Rate or Rhythm for CHF Patients n 1376 patients with h/o afib, EF<35%, sx of CHF n RCT rate vs. rhythm n Outcome: time to death from CV causes, followed 37 months n Results n 27% in rhythm-control group died from CV causes n 25% in rate-control group died from CV causes n HR 1.06 n Other outcomes similar (CVA, worse CHF, all-cause mortality) Roy, et al. NEJM, 2008;358. 9

4/6/15 Rate Control n Previous goal HR: 60-80 bpm at rest; 90-115 bpm during exercise n No evidence getting HR <80 vs. <110 any better for mortality n Guidelines: <110 BPM Ok if no symptoms Van Gelder IC et al. NEJM 2010;362 Groenveld HF, et al. J Am Coll Cardiol 2013 Rate Control n What do I use? n First choice: beta-blockers or calcium-channel blockers n Don’t give if Wolf-Parkinson-White or other accessory pathways n OK to combine nodal-blocking agents n Digoxin is second-line as it does not control HR during exercise January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 10

4/6/15 Rhythm vs. Rate…Bottom Line n Highly symptomatic or unstable: rhythm control n If minimal symptoms: rate control is safe and appropriate (maintain goal HR <110) n Anticoagulation therapy should be continued regardless of the strategy (rhythm vs. rate) What About Cardioversion? n Electrical cardioversion preferred n Best if within 7 days of AF onset n Requires conscious sedation or anesthesia n Most thrombi in atrial fibrillation arise from the LA appendage n Cardioversion can reduce LA appendage function n Peri-cardioversion period is particularly pro- thrombotic n Regardless of mode of cardioversion 11

4/6/15 Electrial Cardioversion n If AF < 48 hrs, AND low stroke risk, can safely undergo cardioversion without anticoagulant therapy n Must be documented! n If AF > 48 hrs (or unknown duration) OR high-risk for stroke (h/o stroke/TIA, mechanical heart valve), then 2 choices: n Anti-coagulate X 3 weeks (therapeutic INR) before cardioversion n TEE to r/o clot n Anti-coagulate for at least 4 weeks afterward n Anti-coagulate also for those who would not normally require coumadin January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 Cardioversion – Thrombus Risk n Other factors besides LA clot may affect stroke risk n Age n DM n LA flow velocity n HTN n One study showed intra-atrial thrombus has been detected by TEE in 15% of patients with AF < 72 hours duration n No difference in thrombus risk between electrical and pharmacologic cardioversion January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 12

4/6/15 Pharmacologic Cardioversion – Stable Patients n Pharmacologic cardioversion in AF n Type 1C n Flecainide n Propafenone n Type III n Dofetilide (do not give out of the hospital) n Ibutilide n Alternative to above: amiodarone January CT et al. AHA/ACC/HRS Practice Guidelines. J Am Coll Cardiol . 2014 The Next Step… 55 yo woman being seen for a new patient visit. Asymptomatic. PMH: HTN (untreated) PE: 150/80, HR 125 Irregularly irregular Does she need anti-coagulation? 1) Yes, with coumadin 2) Yes, with ASA 3) Yes, with coumadin and ASA 4) Yes, with dabigatran (pradaxa) 5) No 13

4/6/15 Key Point… n A rhythm control strategy does not negate the need for anticoagulation therapy n Assuming anticoagulation is indicated Risk/Benefits of Coumadin n Pooled analysis from five primary prevention trials in non-valvular AF n Annual rate of stroke 4.3% in control group n 1.4% risk of stroke in the warfarin group (NNT=32) n Only 20% of subjects >75 yrs; excluded pts at risk for bleed n Need to consider warfarin risks n Symptomatic intracranial hemorrhage 0.4% with warfarin; 0.2% in control n Major bleeding: 2.2% with warfarin; 0.9% in control Bath PMW, et al. European Heart Journal, 2005 14

4/6/15 What About Aspirin? n Two randomized trials evaluated the use of ASA (75mg, 325mg) in primary stroke prevention n Pooled data: Risk of stroke with ASA 4.2%; risk of stroke in controls 6.4% n ASA may be better in preventing non- cardioembolic strokes and non-disabling strokes Bath PMW, et al. European Heart Journal, 2005 Secondary Prevention of Stroke n Risk of stroke with warfarin 3.1%; placebo 10% n Risk of stroke with ASA (300mg) 7.7% EAFT Study Group, Lancet, 1993 15

4/6/15 Anti-Platelets vs. Coumadin? n ACTIVE-W trial n 3335 patients with AF + 1 other stroke risk factor n ASA + clopidogrel vs. coumadin n Outcomes: stroke, non-CNS systemic embolus, MI or vascular death n Stopped early because of superiority of warfarin in preventing vascular events (165 events vs. 234 events). Warfarin even better for those who entered the study already taking it. Active Writing Group. Lancet, 2006;367(9526) Anti-Coagulation n Bottom line…anticoagulation with warfarin superior to ASA and superior to ASA + clopidogrel. Effective in the prevention of primary and secondary stroke. Active Writing Group. Lancet, 2006;367(9526) 16