1. Atrial fibrillation Daniel Gutenberger M.D. Chief Medical Director American General, Milwaukee

2. Normal heart conduction

3. EKG appearance of afib QRS spikes irregularly irregular no uniform P waves

4. Abnormal afib conduction

5. Heart conduction in afib Multiple atrial sites fire 300-600 times/min AV node slows this to HR 150-200 if AV node disease or meds- normal HR if WPW- AV node bypassed- afib can lead to death atrial activity extends to proximal pulmonary vein

6. Atrial flutter with 3:1 block

7. Atrial Flutter treated like afib in UW manual can degenerate into afib mechanism is re-entry circuit regular rhythm with “saw tooth” pattern AV node blocks 2:1, 3:1. 4:1 or variable

8. Classification Duration  Paroxysmal: single or recurrent episodes, terminate spontaneous  Persistent- lasts 7 days  Chronic- lasts 1 year, also called permanent Etiology  Lone or idiopathic: not associated with cardiac disease

9. Many questions with afib duration of episode? will it recur? can sinus rhythm be maintained? symptoms- how well tolerated? underlying heart disease? how great is the stroke risk?

10. Usual Cardiac Causes HTN and LVH cardiomyopathy coronary artery disease valvular heart disease  mitral valve problems especially  atrial enlargement > 4 cm ASD

11. Acute conditions causing afib hyperthyroidism pericarditis pulmonary embolus thoracic surgery - with CABG 1/3 will get it post-op serious illness ie… pneumonia alcohol- holiday heart syndrome

12. Signs and Symptoms of afib often no symptoms palpitations, near syncope SOB, fatigue, decreased exercise neurologic due to CVA/TIA chest pain unusual on exam pulse irregularly irregular and may be in heart failure

13. Diagnostic tests holter to look for duration/frequency echo- most important test stress test to access for underlying CAD TEE- is there a clot prior to cardioversion ? EP study if considering ablation thyroid function lab

14. Complications Embolic  clot forms in L atrium due to stasis, then breaks off causing a stroke or TIA  renal infarct, extremity gangrene hemodynamic  low BP and high HR tachycardia related cardiomyopathy

15. Percent CVA’s due to afib by age

16. Treatment Goals prevent CVA control rate- goal HR 60-90 at rest restore sinus rhythm if possible

17. Natural history of afib 50% no recurrence 50% recur  ½ of these paroxysmal  ½ persistent- requiring cardioversion many of these become chronic afib

18. Rate vs rhythm control Rate control  Rx like digoxin, verapamil, B blocker  prevent CVA with anticoagulant  if large atrial size or failed to stay sinus before  cost effective, fewer hosp. admissions  may have symptoms of being in afib  risk heart remodeling- LV and atrial

19. Rate vs. Rhythm control Rhythm control  less symptoms and better exercise tolerance- often young, active people  Rx with amiodarone, sotolol or flecanide  Cardioversion- electrical vs. meds  relapse rate about 50%  mortality and stroke rate similar to controlling the rate

20. Annual stroke rate

21. Anticoagulation- traditional approach Age less 65  no risk factors ASA 325 mg/day  risk factors warfarin to keep INR 2.0-3.0 Age 65 and above  warfarin to keep INR 2.0-3.0 risk factors: any type of heart disease, HTN, DM or prior stroke

22. Pradaxa (dabigatran) direct thrombin inhibitor reduces stroke risk in afib 35% better than warfarin 2x a day pill no blood monitoring needed for protime INR no diet restriction main side effect- excess bleeding expensive

23. Don’t use Oral Anticoagulant patient refuses or is not compliant active GI bleed hx bleeding problems pregnancy alcoholism recent surgery or serious medical problem

24. Surgical procedures Radiofrequency ablation  AV node, then pacemaker placed  pulmonary vein- 40% recurrence first year  Repeat ablation needed 25%  Complication rate 3%- AV block, tamponade MAZE  isolate and stop abnormal electrical activity and channel it in normal pathway  surgical incision, cryo or radiofrequency ablation

25. Prognosis in afib Depends on underlying problem  lone afib is favorable  CAD or valvular risk + afib risk stroke risk  increased 3-7X  warfarin cuts risk 2/3  ASA is less effective

26. Elderly and afib Afib increases with age  6% in those age > 65 more likely to have CAD,LVH or valvular problems other medical problems makes complications more common stroke risk increases with age

27. Prevalence afib by age

28. Sick Sinus syndrome Degeneration and fibrosis of sinus node and conduction system various arrhythmia’s  sinus brady, sinus arrest or pause  AV block  tachy-brady afib often the fast rhythm present in elderly, 2/3 have heart disease may need pacemaker

29. Underwriting Keys Duration- short episode vs. chronic Underlying heart disease  echo for valves, LVH, atrial size, LV function  stress test for CAD/ischemia Symptoms- none to CHF Appropriate treatment

30. Questions?