AF Flashcards
Causes of AF
SMITH Sepsis Mitral regurgitation Ischaemic heart disease Thyrotoxicosis Hypertension
what are the principles to treating AF
rate control
rhythm control
consider anticoagulation
AF is the most common important arrhythmia, true or false
true
what are the types of AF
permanent - never getting out of it
persistent - succeed in getting out of it
paroxysmal - episodic
paroxysmal can become persistent
yes
once you start the AF journey, you will end up in permanent AF, true or false
true
describe permanent AF
in it
stuck in it
cardiologist will not be able to get you out of it
if you develop AF at >65yr, most cardiologists will treat it as permanent AF
yes
symptoms of permanent AF
asymptomatic fatigue loss of exercise tolerance palpitations shortness of breath exacerbation of heart failure angina if IHD stroke
sick sinus syndrome
‘tachy brady’
patients can have tachy and brady cardia
tachy - usually AF
brady - other heart rhythms
if brady is profound enough, may get syncope
atrial rate of AF
300-600bpm
AVN is protective of this
treatment goals for permanent AF
control ventricular rate
- B blocker: bisoprolol > atenolol
- rate limiting CCB: verapamil, diltiazem
- +- digoxin
bisoprolol indications
arrhythmias and HR control
angina
heart failure
high dose B blockers are used to treat HF?
no, high doses can make it worse therefore start it at a very low dose (1.25mg) then add 1.25mg every 2 weeks and build it up very slowly to max tolerated dose
bisoprolol dose for AF
5mg to 10mg in 1 step
quicker titration for AF
(not low dose for HF)
if someone is asthmatic, what drug do you use for permanent AF
rate limiting CCB
verapamil
diltiazem
digoxin function
acts on ATP Na/K pump at AV node
switches on parasympathetics to slow down the heart
in a ‘healthy’ individual, sympathetic drive tends to overcome effect of digoxin
yes
exercise/running
digoxin is not good for a young/active person in permanent AF
as does pain, anaemia, HF exacerbation in older patients
therefore treat the cause of the bad HR
dihydropyriDINE CCB examples
amloDIPINE
nifeDIPINE
Bisoprolol and verapamil?
verapakill
‘auricular’ appendages
extra features on atria of heart
Virchows triad
hypercoaguability
stasis
endothelial damage
where are you most likely to form a clot in AF
left atrial appendage
perforating lingual artery
supplies Broca’s area
INR target for warfarin
2-3
examples of DOACs
edoxiban
rivaroxiban
apixiban
dabigatran
DOAC drug of choice for AF
edoxiban
DOAC for PE
rivaroxiban
DOACs need monitoring blood tests?
No
CHA2DS2VASc score
congestive heart failure hypertension Age >75 or 65-74 diabetes stroke / TIA vascular disease - MI, PVD Sex category - ignore female risk unless there is another risk
score of 2 on CHA2DS2VASc score needs anticoagulation
yes
indications for warfarin
metallic heart valves
APLS
LMWH indications for anticoagulation in AF
when warfarin INR is subtherapeutic
or prior to operation
warfarin is teratogenic
yes
risk of long term LMWH
osteoporosis
what is the HASBLED score
risk of bleeding if you are anticoagulated
persistent AF
you’re in it and stuck in it unless a cardiologist is successful in getting out of it
goal in persistent AF
rhythm control
cardioversion
cardioversion in AF
one heart rhythm into another
ie from AF to sinus rhythm
types of cardioversion
pharmacological
electrical DC
how does DCC work
enough electrical activity to depolarise all heart cells in hope that the SAN reemerged first to restore sinus rhythm
put them under GA
risk of DCC
arrhythmia: bradycardia, VF
stroke - release of clot from atria
within what duration can you attempt cardioversion
<48 hr NICE
<24 hr SIGN
<12 hr PC
class I antiarrhythmic
flecainide
class III antiarrhythmic
amiodarone
ami’wonder’one
amiodarone is very toxic to the skin, true or false
true
extravasation - leaking of fluid
can causes severe skin necrosis
therefore some units only allow IV amiodarone into a central line
what arrhythmias can flecainide cause
VT
atrial flutter
what questions do you use to screen whether to use flecainide
are you old >65?
do you have anything else wrong with your heart?
management of acute AF in the middle of the night
IV flecainide
fast patient in case of anaesthesia
LMWH
ECG in the morning
management of AF >48 hours
start DOAC anticoagulation
then 5-6 weeks later you do elective DCC
keep them on anticoagulation for 1-6months
also consider rate control with B blocker
paroxysmal AF is a trouble to treat
yes
management goals of paroxysmal AF
maintain sinus rhythm
maintain AF
explain maintaining AF in paroxysmal AF
instead of chopping and changing in and out of AF this can be very symptomatic and troublesome, leave them in AF and treat as permanent
management of paroxysmal AF in younger patients
antiarrhythmic drugs to stay in sinus rhythm
- bisoprolol
- flecainide (if not old or has other heart conditions)
therefore: low dose of each of these in combination
(bisoprolol to protect against flutter and flecainide for AF)
- propafinone (Ic and B blocker combo drug)
- dronedarone
- amiodarone
- sotalol (B blocker + amiodarone)
side effects of B blockers
cold peripheries
poor sleep
fatigue
digoxin is better for permanent/paroxysmal AF
digoxin is better for permanent AF rather than paroxysmal
flecainide can cause atrial flutter
yes
enhances conduction at AVN and can come in with atrial flutter despite AF being controlled
what is pill in the pocket
can self administer flecainide within a certain timeframe for paroxysmal AF to avoid long term effects
need to try normal therapy first
side effects of amiodarone
photosensitivity thyroid abnormalities grey waxy complexion irreversible pulmonary fibrosis liver skin necrosis
non-pharmacological management of paroxysmal AF
venous access catheter - electrical
radiofrequency ablation around pulmonary veins
RF PVI - pul vein isolation
create a burn electrical activity cannot escape
cold cryo ablation
management of atrial flutter
same as AF
atrial flutter caveats
harder to control ventricular rate
more likely to respond to electrical therapy
