Atrial Fibrillation Flashcards
What is AF?
electrical activity in atria becomes disorganised
random muscle twitching
irregularly irregular pulse
both AF and ventricular ectopics give an irregularly irregular pulse. how can you distinguish between them?
in ventricular ectopics it will disappear when the heart rate gets above a certain threshold
What are the effects if atrial fibrillation?
tachycardia
heart failure
increased risk of stroke
What causes atrial fibrillation?
sepsis
mitral valve pathology
ischaemic heart disease
thyrotoxicosis
hypertension
alcohol and caffeine
How does AF typically present?
asymptomatic
palpitations, SOB, dizziness, or syncope
symptoms of associated conditions (e.g., stroke, sepsis)
What investigation is required in all patients with suspected AF? What would it show?
ECG
- absent P waves
- narrow QRS complex tachycardia
- irregularly irregular ventricular rhythm
In what cases would you carry out an echocardiogram in an AF patient?
valvular heart disease
heart failure
planned cardio version
What is paroxysmal atrial fibrillation?
episodes of AF that occur and resolve back to sinus rhythm
spontaneous
last between 30s and 48hrs
What are the next steps in a patient with a normal ECT and suspected paroxysmal AF?
24hr ambulatory ECG
cardiac event recorder fr 1-2 weeks
What is valvular AF?
AF with mitral stenosis or mechanical heart valve
How do you treat AF?
beta blocker (bisoprolol) + a DOAC for anticoagulation (apixiban)
What do you give to sedentary people with AF for rate control?
digoxin
What drugs can be used for rate control in AF?
beta blocker (first line)
calcium channel blockers (not in heart failure)
digoxin (only in sedentary people with AF)
How do you treat AF with rhythm control if present for <48 hrs or causing life threatening haemodynamic instability?
cardio version:
electrical defibrillator
flecainide
amiodarone (if structural heart disease)
How do you treat AF with rhythm control if present for >48 hrs?
electrical cardio version is recommended
amiodarone is used to prevent recurrence
patient should be anti coagulated for at least 3 weeks before cardio version
What drugs are used for long term rhythm control in AF?
beta blockers = first line
dronedarone = 2nd line for patients who have had successful cardio version
amiodarone = for patients with heart failure or left ventricular dysfunction
How do you treat paroxysmal atrial fibrillation?
flecanide - take one tablet when symptoms appear
also need to be anticoagualted
When is ablation necessary?
What it is?
when drug treatments have not been well tolerated
small burns or freezes heart cells to break up the electrical rhythm
Why are DOACs better than warfarin?
do not require INR monitoring
What is the most common DOAC used?
apixiban
How does warfarin affect INR and what does this mean?
prolongs prothrombin time (time it takes for blood to clot)
What is the effect of INR being too high? Or too low?
too high = increased risk of bleeding
too low = increased risk of stroke
What tool is used to assess whether a patient should be started on anticoagulation? What does it consider?
CHA2DS2VASc
congestive heart failure
hypertension
age >75 (scores 2)
diabetes
previous stroke (scores 2)
vascular disease
age 65-74
female sex
What factors increase risk of bleeding?
age 75+
eGFR<60
bleeding previously
low iron
taking anti platelet medication
