Treatment of Atrial

FibrillationM Samson – PGY-2Riverside Campus

July 17, 2015 Academic Day

Outline• Definitions• A Fib in the acute setting

o Electrical Cardioversiono Chemical Cardioversion

• Chronic Treatments o Rate Control o Rhythm Control

• Stroke Prophylaxis o Risk stratificationo VKA o NOACs

Definitions• Paroxysmal AF – AF that terminates

spontaneously or with treatment within 7 days of onset. Episodes may recur with variable frequency.

• Persistent AF – Lasting more than 7 days• Long-Standing Persistent – more than 12 months• Permanent – When the patient and clinician make

a joint decision to stop further attempts of restoring sinus rhythm

• Non-Valvular A fib – AF in the absence of rheumatic valve disease, prosthetic valve, or mitral valve repair.

A Fib in the ED

• Treatment depends on several factors. The 2 most important ones are:o 1) hemodynamic compromise o 2) time of onset

Acute Onset A FibHemodynamic

Instability

Electrical Cardioversion.150

J synchronized.Anticoagulate for 4

weeks

YesNo

Onset

<48hrs

Rate Control. Anticoagulate for 3 weeks

before rhythm control.

Offer rate or rhythm control. Electrical Cardioversion is

appropriate.

Yes No

Acute Onset A Fib - ?anticoagulation

• If onset is greater than 48 hrs offer heparin for anticoagulation for subtherapeutic anticoagulation or no anticoagulation. Continue heparin based on risk stratification. Continue for at least 4 weeks.

• If onset is less than 48 hrs offer anticoagulation if 1) stable sinus rhythm not restored within 48hrs, 2) there is a high risk of recurrence 3) it is recommended based on risk stratification.

Chronic Treatment

• Rate Control• Rhythm Control• Stroke Prophylaxis

Risk Stratification – Stroke Vs Major

Bleeding

• CHA2DS2-VASc – determines risk of stroke

• HAS-BLED – determines risk of major bleed

CHA2DS2-VASc• C – (C)HF• H – hypertension• A – Age, 2 points if greater than 75, 1 if greater

than 65• D – diabetes• S – 2 points for previous stroke or TIA• V – peripheral vascular disease• Sc – Sex category, 1 for female

Case 1 – Mr Couminda• Mr. Couminda is a 60 y/o gentleman. He has been

to the ED on 3 occasions over the past yr and treated for atrial fibrillation with cardioversion. Today, he denies any palpitations, chest pains, orthopnea, PND, headaches, visual disturbances, claudication, erectile dysfunction or signs of neuropathy. He has had no previous stroke or TIA

• You have been treating him for T2DM and HTN. • His current medications are

o Perindopril 4 mg dailyo Amlodipine 10 mg dailyo Metformin 500 mg BID

• Exam:o BP 124/78, HR 66, O2 sat – 99% on RAo CVS – S1/S2 normal, regular rhythm, no murmur, no JVP, no carotid

bruitso Resp – GAEB, no crackleso Abdomen – no masses, no abdominal bruitso Extremity – sensation intact to light touch, well perfused, edema

present

• Investigations:o ECG – normal sinus rhythmo Bloodwork – CBC – WNL, Electrolytes – WNL, Creat 74, LDL 1.9, TSH

1.43, A1c 6.0% o ECHO – EF 60%. No valvular anomalies.

What is his CHA2DS2-VASc?

• A) 0

• B) 1

• C) 2

• D) 3

• E) 4

What is his CHA2DS2-VASc?

• A) 0

• B) 1

• C) 2 – CHF-0, H-1, A-0, D-1, S-0, VASc-0, Male

• D) 3

• E) 4

HAS-BLED• H – hypertension• A – abnormal renal or hepatic function• S - stroke• B – bleeding• L – labile INRs• E – elderly• D – drugs (antiplatelet, NSAIDs) or ETOH

• Do not withhold anticoagulation based on fall risk!

CHA2DS2-VASc

• If 0 – do not offer anticoagulation• If 1 – consider offering ASA or anticoagulation• If 2 or greater and non-valvular AF – offer

anticoagulation with VKA or NOAC• If 2 or greater and valvular AF – offer VKA

VKA - Warfarin• Target is INR of 2.0 - 3.0 with non-valvular AF and

2.0 – 3.0 or 2.5 – 3.5 with prosthetic valves depending on type of prosthesis and which valve

• INR should be checked weekly after initiation and at least monthly when stable

• If INR is very labile and GFR >15, consider changing to NOAC

NOACs

• Dabigatran, Rivaroxaban, and Apixaban currently indicated for stroke prevention in AF

• No INRs or monitoring except yearly renal function

• Need to be titrated in moderate renal impairment and should not be used in severe renal impairment

• Should not be used in valvular AF• Ne reversible agent available• Yearly creatinine should be monitored

Cost – from Rx files

• Warfarin – $15/month• Dabigatran - $110/month• Rivaroxaban - $100/month• Apixaban - $140/month

NOACs and Renal Impairment

Rate Vs RhythmRate Control Rhythm Control

• Persistent AF• Less symptomatic• Age >65• HTN• No history of HF• Past failure of

antiarrhythmics

• Paroxysmal or new AF• More Symptomatic• Age <65• No HTN• HF exacerbated by AF• No past failure of

antiarrhythmic drugs

Rate Control • Offer for patients with all types of AF unless:

There is a reversible causeThey have heart failure caused by AF (rhythm control may be more appropriate)New onset AFA flutter and ablation is suitable

• Can use o 1) standard beta-blocker (not sotalol), o 2) Non-DHP Ca channel blocker. o Consider 3) digoxin if they are sedentary.

• If decompensated heart failure – start with beta-blocker then add digoxin if beta blocker not controlling rate adequately.

Goals of Rate Control

• Asymptomatic patients with preserved LV function - <110 bpm.

• Symptomatic patients or LV dysfunction <80 bpm.

FYI - Dosages

Rhythm Control• If greater than 48 hrs AF – anticoagulate for 3

weeks before rhythm control• Electrical Cardioversion is reasonable• Pharmacological – propafenone, dofetilide,

flecainide, ibutilide are appropriate• “Pill in a pocket” with propafenone or or flecainide

if they have used these drugs in a supervised setting. Need to use in addition to beta-blocker or Ca Channel blocker. For paroxysmal AF.

• Consider cardiology referral for ablation if symptomatic and refractory to pharmacological options.

Resources

Rx Files – 9th Edition