Basics of Atrial Fibrillation. By Mini Thannikal NP-BC Mount Sinai St Luke s Hospital New York, NY

Transcription

1 Basics of Atrial Fibrillation By Mini Thannikal NP-BC Mount Sinai St Luke s Hospital New York, NY

2 Atrial Fibrillation(AF) is a supraventricular tachyarrhythmia characterized by uncoordinated atrial activation which causes deterioration of hemodynamics ex: fall in atrial mechanical function and reduction in cardiac output. Most common sustained cardiac rhythm disturbance Increasing in prevalence with age Hemodynamic impairment and TE events related to AF results in significant morbidity, mortality

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5 Classification of Atrial Fibrillation Paroxysmal AF: Episodes of AF that last less than 7 days Persistent AF: AF that last more than 7 days Long standing AF: AF that has been persistent for more than one year Permanent AF: AF that is resistant to cardioversions

6 Modifiable Risk Factors Aggressive Risk Factor Modification in AF Should be Standard Hypertension( early treatment ) Diabetes Mellitus (Glycemic Control) Obesity (keeping a BMI<30) Sleep Apnea Alcohol/drugs ( no alcohol /drugs)

7 The most common site of the rapid atrial firing that triggers AF is the PVs

8 Clinical features Palpitations Fatigue Dyspnea Effort intolerance Lightheadedness 25% patients with AF are asymptomatic

9 Diagnostic Evaluation ECG Ambulatory monitoring 24 hour holter monitoring ECHO to evaluate LA size. LVH, LV function Stress test for ischemia evaluation

10 Baseline EKG

11 Case 68 yr man with syncope in the subway and is brought to the ED; past history of coronary artery disease with one stent; hypertension; diabetes; COPD. Upon arrival in the ED his ECG shows atrial fibrillation at a rate of 160 bpm. BP 100 / 60, Oxygen sat 91%. Diltiazem is given with temporary rate control to 100 however despite a diltiazem drip his rate continues to go up to associated with dizziness and near syncope. Echo shows a dilated left atria. 1. Which patients are candidates for cardioversion? 2. What is the difference between electrical and pharmacologic cardioversion? 3. Which patient with AF needs an anticoagulant vs. an antiplatelet medication?

12 Key Management of AF Stroke Prevention Rate Control Rhythm Control Risk assessment megatrend CHA2DS2-VASC is the predominant assessment tool to predict stroke risk

13 CH A2 D S2 VASc Max score 9 C Congestive heart failure (or Left ventricular systolic dysfunction) 1 H Hypertension: blood pressure consistently above 140/90 mmhg (or treated hypertension on medication) 1 A2 Age 75 years 2 D Diabetes Mellitus 1 S2 Prior Stroke Prior Stroke or TIA Prior Stroke or TIA or thromboembolism 2 V Vascular disease (eg. peripheral artery disease, myocardial infarction, aortic plaque) 1 A Age years 1 Sc Sex category (ie female gender) 1 Score Risk Anticoagulation Therapy Considerations 0 Low No antithrombotic therapy (or Aspirin) No antithrombotic therapy 1 Moderate Oral anticoagulant (or Aspirin) Oral anticoagulant (patient preference) >2 High Oral anticoagulant Oral anticoagulant (Oral anticoagulation: using either a new oral anticoagulant drug (eg Apixaban, rivaroxaban or dabigatran) or well controlled warfarin at INR ) 1 Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology. Eur Heart J Oct;31(19):

14 HAS-BLED score evaluates bleeding risk in patients with AF. Higher the score higher the

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16 Practical Considerations for Using Novel Oral Anticoagulants in Patients with Atrial Fibrillation

17 Which patients are candidates for cardioversion? (atrial flutter and atrial fibrillation) STEP 1 New-onset atrial fibrillation Hemodynamically unstable Atrial fibrillation has no apparent cause (COPD, infection, heart failure) Heart failure thought to be primarily caused by atrial fibrillation Anticoagulated (preferred approach)

18 What is the difference between electrical and pharmacologic cardioversion? STEP 2 Elective versus emergency cardioversion Electrical versus chemical cardioversion 1. Hemodynamically unstable 2. Duration of atrial fibrillation 3. Availability 4. Risk of pro-arrhythmia (VT/VF)

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20 Chemical vs Electrical How urgent (look for primary cause) Underlying heart disease/heart failure Medications Duration unclear-do TEE Electricity is Cheap Universally available More effective Less proarrhythmic

21 What is the difference between electrical and pharmacologic cardioversion?

22 Chemical Cardioversion (Vaughan Williams classification of antiarrhythmic drugs: class 1c or III) Oral: Flecainide (pill-in-pocket) 1C Dofetilide III Propafenone(Rythmol)(pill-in-pocket)1 C Amiodarone III Intravenous: Amiodarone: efficacy 50% Ibutilide 70% Complexity: EF, sinus bradycardia, CHF Preexcitation

23 Which patient with AF needs an Anticoagulant vs an Antiplatelet medication? Anticoagulation should be considered for all patients with AF When feasible, TEE should be done as rhythm control is planned Anticoagulation is determined by CHADSVASC score Type of and duration of atrial fibrillation is not important (paroxysmal and persistent atrial fibrillation or atrial flutter have same risk) Antiplatelet medications have limited role

24 TEE is critical:

25 Cardioversion and Anticoagulation Anticoagulate for 4-6 weeks prior to and 4 weeks after cardioversion TEE and immediate cardioversion should be followed by 4 weeks of anticoagulation If pt reverts, start amiodarone and cardiovert after 4 weeks Rhythm control is usually more difficult in elderly

26 Management of AF Rate vs Rhythm Control Rhythm control is preferred in presence of significant symptoms and recent AF Less likely to tolerate antiarrhythmics bradycardia more likely to occur with amio, sotalol proarrhythmia with Class 1C used if no CAD and normal LV Often have bradycardia and need pacemakers

27 AV Nodal Ablation

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29 Management of Atrial Fibrillation Benefit of achieving Sinus Rhythm Fewer symptoms Low risk of stroke No long term anticoagulation Better quality of life Better survival Rate control Improved compliance Avoid AA side effects Low cost of treatment Rate control at rest: 80 bpm exercise: 110 bpm with 6 min walk

30 Efficacy of AADs: SAFE-T Singh BN, et al. NEJM 2005;352: Double blind Placebo-controlled trial amio and sotalol are equally efficacious on converting

31 Therapy to maintain sinus rhythm in patients with recurrent paroxysmal or persistent atrial fibrillation et al. Circulation 2011;123:

32 The Ideal Pulmonary Vein Isolation (PVI) Candidate Ideal Severe Symptoms Small LA Paroxysmal AF Young No Structural Heart Disease Otherwise Healthy Lean Absolute Contraindications: Less Ideal No Symptoms Large LA Longstanding, Persistent AF* Elderly (>80 yrs) Cardiomyopathy, Valve disease, etc. Multiple Medical Comorbidities Severely Obese LA thrombus Inability to anticoagulate

33 Catheter Ablation:Isolates or eliminates arrhythmogenic tissue in atrial myocardium in order to eliminate the tachyarrhythmia.electromagnetic mapping(carto)is non-fluoroscopic, catheter based -technology which provides real time three dimensional reconstruction of cardiac chamber anatomy and voltage mapping with identification of ablation sites. Types of ablation: Radiofrequency Ablation CryoBalloon ablation

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35 PAF: Final pictures (overlapping lesions) Catheter: Thermocool catheter (Energy watts,temp Red dots denotes sites of ablation according to the ablation strategy

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37 Referral Criteria from Primary care Atrial Fibrillation under 30 years of age rate control of atrial fibrillation is resistant to "usual" drugs patient is suitable for cardioversion further assessment is required - e.g. valvular heart disease patient with resistant heart failure frequent attacks of paroxysmal atrial fibrillation syncopal attacks due to atrial fibrillation NHS: Treatment guidelines NICE: National Institute of Clinical Excellence

38 Non pharmacological prevention of stroke in AF:LAA Closure Device In nonvalvular AF, over 90% of stroke-causing clots that come from the left atrium are formed in the left atrial appendage Patients with high risk of stroke and high risk of bleeding what do we do? WATCHMAN LAA closure FDA approved WATCHMAN is delivered via a transfemoral approach and is designed to close the left atrial appendage ( LAA) to prevent migration of blood clots, thus reducing the risk of stroke and systemic embolism

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41 Post-operative Atrial Fibrillation Pre-op Beta blocker in high risk patients Elderly, history of AF Rate control acutely Cardioversion Antiarrhythmic with conversion for one month if symptomatic, otherwise avoid antiarrhythmic

42 AF: Pregnancy Anticoagulate as indicated Heparin 1st trimester Coumadin 2nd and 3rd Control rate with CCB, BB or digoxin Convert with antiarrhythmic if stable Cardioversion if unstable

43 AF: Miscellaneous Hyperthyroidism: Rate control Anticoagulate as needed Wait till euthyroid to convert MI: Cardiovert if unstable IV amio if poor LV function BB and heparin

44 Thank You!