NILOFAR RAHMAN, MDAMIT KUMAR, MD

ATRIAL FIBRILLATION

DEFINITION

A SVT with uncoordinated atrial activation with constant deterioration of atrial mechanical function

On EKGs it is defined by replacement of consistent P waves with rapid oscillations that vary in size, shape and timing ass. With an irregular RVR when AV conduction is intact.

EPIDEMIOLOGY

CLASSIFICATION

PAROXYSMAL: Self terminates< 7 days, usu, within 24 hrs.

PERSISTENT: > 7 days, terminate spontaneously or by cardioversion

PERMANENT: > 1 YR, CV attempted or failed

LONE: Without any structural heart disease

ASSOCIATED DISEASES

HTN: 1.4 fold increase risk

CHD: when complicated by acute MI or heart failure CASS trial: RR was 1.98 in 7 yrs

VALVULAR HEART DISEASE: MS, MR, TR: 70% RISK MS, MR: 52% ISOLATED MS: 29%

HYPERTROPHIC CMP:

CONGENITAL HEART DISEASE

OTHERS: hyperthyroidism, PE, COPD, lupus myocarditis OSA: reduced reccurence with treatment

CLINICAL MANIFESTATIONS

SYMPTOMATIC OR ASX EVEN IN SAME PT.

PALPITATION/CP/DYSPNEA/FATIGUE/LIGHTHEADEDNESS/SYNCOPE

EMBOLIC COMPLIC. OR HEART FAILURE

POLYURIA: ANP

ASS. RVR- CMP

EVALUATION

H&P:

EKG: verify AF

CXR: lungs, vasculature and cardiac outline

ECHO TTE: size and function of chambers, valvular heart diseases TEE: thrombi in left atrium

TSH

ADDITIONAL TESTING: EXERCISE TEST HOLTER/EVENT MONITOR

GENERAL PRINCIPLES OF TREATMENT

RHYTHM CONTROL•CONVERSION TO NSR•MAINTAINENCE

RATE CONTROL•MEDICATION

•RADIOFREQUENCY ABLATION CHOOSING B/W RATE AND RHYTHM CONTROL

PREVENTION OF SYSTEMIC EMBOLIZATION

RATE VS. RHYTHM CONTROL

AFFIRM AND RACE TRIALS: 2 CONCLUSIONS-

Embolic event occur in equal frequency

lower incidence of primary end point with rate control strategy

TREATMENT

RATE CONTROL

• Beta blockers

• Calcium channel blockers

• Digoxin

• GOALS: HR<80 bpm, 24 hr. Holter average <100 bpm, HR < 110 bpm in 6 min. walk

• Non pharmacologic method: radiofrequency ablation and pacemaker implantation

RHYTHM CONTROL

PHARMACOLOGIC

DIRECT CURRENT CARDIOVERSION

Anticoagulation for 3-4 weeks before CV

Anticoag for 1 month after CV

usu done in hemodynamically unstable pts.

success rate is 75-93%, inversely related to atrial size and duration

…contd. RHYTHM CONTROL Maintenance of NSR:

20-30% maintain NSR > 1 yr. w/o antiarrythmics

duration of <1 yr, atrial size < 4 cm.

reversible causes

Amiodarone is known to be most effective

CTAF and AFFIRM trials

Flecainide and propefenone in those without heart disease

ANTICOAGULATION IN AF

RISK OF STROKE IS 3-5% WITHOUT ANTICOAGULATION

CHADS2 SCORE

SCORE OF 0: ASA

SCORE 1-2: ASA/WARFARIN

SCORE > 2: WARFARIN, INR GOAL 2-3

DABIGATRAN

APPROVED IN 10/10

RE-LY TRIAL EVALUATED SAFETY OF 2 DOSES

RESULTS:

Rate of stroke was lesser High dose - more effective than warfarin

Risk of bleeding was lesser in low dose

All-cause mortality was reduced

DISADVANTAGES

Twice dosing

High cost

Lack of an antidote

Dose adjustment for those with CKD

lack of long term safety data

THANK YOU