Mount Carmel Health Partners Clinical Guidelines Atrial Fibrillation | Page 6

Chronic anticoagulation:
• Is recommended for most AF patients due to the high rate of AF
recurrence and devastating outcomes from strokes
• Patients with paroxysmal AF should have chronic oral
anticoagulation (OAC) according to their risk score
• If AF is definitely known to be secondary to surgery or other
illness, OAC can be stopped after 6 months if there are no
clinical symptoms or recurrence of AF, the secondary cause has
been addressed, and an ambulatory telemetry test at 6 months
is negative
Assess stroke risk:
Utilize the CHA 2 DS 2 VASc score (see Table I), which helps predict
future stroke risk in patients who do not receive anticoagulation.
HAS-BLED Scoring
Each checkmark = 1 point
Kidney function: serum
creatinine >2.26
• Liver function: bili >2X ULN
and LFTs >3X LN
S troke history
B leeding history or predisposition
L abile INRs: TTR 60%
E lderly: >65 years
D rugs:
• ETOH use
• ASA or NSAID use
•
Warfarin Mandatory:
• Valvular heart disease
Warfarin Preferred:
• Patient is taking meds that interact with NOAC
• Patient prefers warfarin and TTR is at least 65% to 70%
• NOAC is cost prohibitive
• Chronic kidney disease
NOAC Preferred:
• For most patients with nonvalvular AF, unless warfarin is
preferred
• If TTR on warfarin is less than 65% to 70% (not due to
noncompliance)
• If patient has limited access to INR monitoring
• If frequent procedures interrupt anticoagulation
• If patient is taking meds that interact with warfarin
• If it is necessary to achieve therapeutic effect quickly
Assess and manage bleeding risk:
Bleeding risk is not a reason to withhold anticoagulation. Manage
modifiable bleeding risk factors.
H ypertension (SBP > 160 mmHg
A bnormal:
Choose desired anticoagulant:
The choice of warfarin versus NOAC (novel oral anticoagulant:
apixaban, rivaroxaban, edoxaban, or dabigatran) is based on
medical conditions, medication interactions, and on TTR (time in
therapeutic INR range).
Using the score:
Score 0 - 1 = low risk
Score 2 = moderate risk
Score 3 = high risk
Uncertain:
• Stable coronary artery disease
• High GI bleed risk (some NOACs increase GI bleeding)
• Frail elderly patients: age ≥75, weight <60 kg, eGFR 30-49
and/or polypharmacy
For patients at high risk,
consider:
• Optimizing blood
pressure control
• More frequent INRs in
the first 3 months of
warfarin
• Anticoagulation clinic
management
• Fall prevention
• Use of NOAC
Switch between anticoagulants wisely:
Warfarin → NOAC
• Stop warfarin
• Start apixaban, or dabigatran, as soon as INR is less than 2
● Start rivaroxaban when INR less than 3
● Start edoxaban when INR is less than or equal to 2.5
Considerations:
• Regardless of bleeding risk, concurrent aspirin/clopidogrel with
oral anticoagulation should be used ONLY for patients with a
recent history (12 months) of stent placement, high risk
mechanical heart valve placement, or acute coronary syndrome.
• Patients with stable CAD may be managed with oral
anticoagulants alone; adding aspirin increases bleeding risk
and does not reduce MI/stroke risk.
• Even after a significant GI bleed or intracranial hemorrhage,
consider restarting chronic anticoagulation in patients at risk
for thrombotic events.
• Consider referral for patients with possible left atrial occlusion.
Apixaban → Warfarin
• Start warfarin while patient is still taking apixaban
• Check INR on day 4 of overlap
• If the INR is ≥2.0, stop apixaban and repeat INR after 1 to 2
days of warfarin alone
• If the INR is <2, consider continuing apixaban along with
warfarin; repeat INR 1 to 2 days later
Dabigatran → Warfarin
• Start warfarin while patient is taking dabigatran. Stop
dabigatran 1 to 4 days later with timing based on patient’s
creatinine clearance (CrCl) and INR level
• If CrCl is >50: check INR on day 4 of overlap
▫ if INR is ≥2, stop dabigatran, repeat INR after 1 to 2 days
of warfarin alone
▫ if INR <2.0, consider continuing dabigatran along with
warfarin; repeat INR 1 to 2 days later
• If CrCl = 31-50: stop dabigatran 2 days later and check INR
after 2 days of warfarin alone
• If CrCl <30: stop dabigatan 1 day later and check INR after 3
days on warfarin alone
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AFib - 6