Atrial Fibrillation Jay H. Lee, MD Denver Health Medical Center Wednesday 2 July 2008

Goals & Objectives Learn the importance of anti-coagulation Review the “minimum” evaluation for patients with atrial fibrillation Understand the literature between rate and rhythm control

The Case 59 yo Hispanic male with PMH notable for AF, HCV, and PUD presents with left arm and facial numbness one day PTA. Patient went to bed, hoping it would go away. It did not… He was diagnosed with AF last year and has had palpitations lasting approx 24 hours weekly for the past several months.

J Am Coll Cardiol 2006; 48: e Basics Most common arrhythmia 2.3 million patients in 2001 Types –Paroxysmal: self-terminating –Persistent AF: lasts more than 7 days –Permanent AF

JAMA 2001; 285(18): Is AF common? Prevalence increases with age –3.8% of patients 60 years of age –9.0% of patients 80 years and older

J Am Coll Cardiol 2004; 43(1): How does AF present? PalpitationsDyspneaFatigueLightheadednessSyncope Asymptomatic or “silent” AF occurs frequently (17-24%)

Back to the case… ROS positive for blurry vision without vision loss, slurring speech, weakness, and lightheadedness without syncope No medications SH: –Prior IVDU (cocaine) –EtOH (1-2 beers daily; more recently d/t “stress”) –No tobacco

Predisposing Conditions CV disease –HTN, CAD, CHF/CM, valves (MR) Alcohol use Hyperthyroidism Pulmonary disease “Lone” AF: 45% have no underlying cardiac disease

J Am Coll Cardiol 2000; 35: Risk of Stroke & Death Stroke Prevention in AF –Longitudinal cohort study –460 pts with intermittent AF (documented sinus rhythm in last 12 months) –1552 pts with sustained AF –Two years of follow-up –All patients took ASA

J Am Coll Cardiol 2000; 35: Results? Annualized rate for ischemic stroke –Intermittent AF 3.2% –Sustained AF 3.3%

Risk Factors for Anticoagulation Weaker –65-74 years of age –CAD –Female –Thyrotoxicosis Moderate –>75 years of age –DM, HTN –CHF (LVEF < 35%) High –Mitral stenosis –Previous CVA, TIA, TE –Prosthetic heart valve

Recommended Therapy No risk factors –Aspirin (81 to 325 mg daily) One moderate risk factor –Aspirin (81 to 325 mg daily) –Warfarin (Coumadin; INR 2.0 to 3.0, target 2.5) Any high risk factor or more than one moderate risk factor –Warfarin (INR 2.0 to 3.0, target 2.5) –If patient has a mechanical valve, target INR is greater than 2.5

J Am Coll Cardiol 2006; 48: 882. Anticoagulation Therapy II Warfarin (INR ) –Rheumatic HD (mitral stenosis) –Previous TE –Persistent atrial thrombus on TEE –Prosthetic heart valves Guidelines –American College of Cardiology –American Heart Association –European Society of Cardiology

JAMA 2001; 285(22): CHADS2 Clinical Parameter Points Congestive Heart Failure 1 Hypertension 1 Age (>75 yo) 1 Diabetes 1 Secondary prevention (CVA, TIA) 2

*Events per 100 person-years CHADS2 score Warfarin* No Warfarin* Risk Low Mod Mod High High High

Physical Examination VS: –T36.5 o –HR 58 –RR 18 –BP 119/70 –99% on 2L NC

What tests would you order? “Minimum evaluation” –ECG –Chest radiography –Trans-thoracic echocardiography –Thyroid function tests History and physical is also important…

Data CBC & INR wnl –Hct 47 –INR 0.92 BMP & LFTs wnl –K –sCr 1.1 LDL 62 TSH 2.42 (wnl) Troponin negative (<0.03)

ED Course EKG showed NSR (57 bpm) with no acute changes nor AF. CXR was normal. CT of head showed no acute intracranial abnormalities. LP showed no sign of infection or other processes. Patient was started on IV heparin and admitted to Family Medicine for TIA.

Hospital Course Carotid US and TTE were both normal. MRI of the brain did reveal a small infarct in the left thalamus. Patient was discharged home on warfarin and atenolol.

Lancet 2000; 356: Rate vs Rhythm Control Pharmacological Intervention in AF (PIAF) –RCT 252 pts with AF between 7 and 360 days duration –Rate control (125 pts; diltiazem) –Rhythm control (127 pts; amiodarone) –No difference in quality of life

N Engl J Med 2002; 347: RACE Rate Control vs Electrical Cardioversion for Persistent AF –522 patients with persistent AF –End-points (2.3 yrs): cardiovascular event, CHF, TE, bleeding, pacemaker, adverse drug effect –60 of 256 pts in rate group (22.6%) –44 of 266 pts in rhythm (17.2%)

N Engl J Med 2002; 347: AFFIRM… AT Follow-up Investigation of Rhythm Management –RCT with 4060 patients with AF –Primary end-point overall mortality –Mortality at five years 21.3% in rate group 23.8% in rhythm group

J Am Coll Cardiol 2001; 38: Rate Control Target ventricular rate –60-80 bpm at rest – bpm during exercise Metoprolol ( mg) Diltiazem ( mg) Digoxin ( mg)

Approach to AF See NEJM

Conclusion Anti-coagulation is important The “work up” for patients with AF is not extensive Consider rate control