Atrial Fibrillation Flashcards
Triggers
Infection ( resp + UTI most common infections to get)
Valvular disease - vegetation from IE, degenerative valve - listen for mitral regard
Change in heart structure -
Metabolic - thyrotoxicosis
What investigations would you do?
ECG would confirm patient is in Afib.
ECHO - is there a clot?
Ask patient and look at old ECG to know if this is new or not
look for the cause ;
FBC and CRP for infection
and Urinalysis for UTI
Chest Xray - is there a concurrent LRTI
TFTs
LFTs- poor liver ( or renal fxn) might influence decision to anticoagulant
U+E electrolyte abnormalities that may have precipitated the fast afib
Why do you care if its new onset fib?
New - can cardiovert
What is a fib?
Atrial Fibrillation is a superventricular tachyarrhythmia. Characterised on an ECG by absent P waves and irregularly irregular rhythm.
What are the symptoms of Fib?
asymptomatic
or palpitations + SOB
Who is suitable for emergency cardio version?
carry out emergency electrical cardioversion in someone with life threatening haemodynamic instability caused by a new onset atrial fibrillation
If not haemodynamically unstable but was symptomatic with fast afib, what can be done?
Someone with fast fib and symptomatic - can try to cardiovert after rate control and anti coagulated for 6 weeks, then try to correct the rhythm with cardioversion
Why 6 weeks of anticoagulation after cardioversion?
Biggest risk of clot formation is highest in the first 6 weeks following cardioversion
What drugs are given to patient with afib?
Rate control
- B blocker or a rate limiting CCB
- if they don’t work then consider digoxin
Anticoagulate
- DOAC
> dabigatran
> apixaban, rivaroxiban, edoxaban
- Warfarin
What are the side effects of digoxin?
Can cause arhythmias Cerebral impairment diarrhoea dizziness N,V skin rashes
warfarin vs doac ?
Warfarin and dabigatran have anitdotes
warfarin can be reversed with vit K
DOACs have lower risk of bleeding and require one time dosing, less drug-drug interactions, no bridging they work straight away
DOACs are more expensive
Warfarin requires continuous monitoring and adjustments
warfarin interferes with lots e.g. clarithromycin, NSAIDs, grapefruit juice increases INR so higher risk of bleeding, alcohol ( tell patient not to binge drink ), st johns wart
Who is anticoagulated long term with fib?
CHADS2VASc score 2 or more CCF Hypertension Age over 75 2 Diabetic Stroke or TIA 2 Vascular disease - MI, or PAD Age over 65 gets 1 Sc sex female 1
How do B blockers work on the heart?
They target b1 receptors ( b1 most in because only have 1 heart) and block sympathetic drive, prevent production of cAMP and cause heart to beat more slowly and with less force.
