Atrial Fibrillation Flashcards
What is acute AF?
AF lasting less than 30 seconds diagnosed by ECG
How may atrial fibrillation present?
Incidental finding of irregular pulse SOB Palpitations Fatigue Syncope/dizziness Chest discomfort Stroke/TIA
What is paroxysmal AF?
Recurrent (>2) episodes that last less than 7 days
Or
Recurrent (>2) episodes that last <48 hours and are stopped with cardioversion
What is recurrent AF?
Recurrent episodes:
Continuous for >7 days
Or
Continuous for >48 hours and stopped with cardioversion
What is persistent AF?
Continuous AF of greater than 12 months duration
What is permanent AF?
Continuous AF, and a joint decision by patient and clinician to cease attempts to revert to systolic rhythm
Which patients with an irregular pulse on examination should have an ECG?
All patients with irregular pulse! Trick question
Use ambulatory ECG if symptomatic episodes are 24 hours apart
Which patients with suspected AF should have an echo?
Perform echocardiography if:
Baseline echo necessary for long term management
Rhythm control strategy including cardioversion is considered
High risk of structural/functional disease (HF/murmur)
Clinical risk stratification for anti thrombotic therapy is needed
When should transoesophageal echo be performed?
If Transthoracic echo reveals abnormality
If transoesophageal guided cardioversion is being considered
When is rate control considered for he management of AF?
Offered EXCEPT when:
AF has a reversible cause
Heart failure due to AF
New onset AF
Rhythm control more suitable based on clinical judgement
What is rate control of AF?
First line:
Standard beta blocker- eg other than sotalol
Or rate limiting calcium channel blocker- diltiazem
Consider digoxin monotherapy if non paroxysmal
Second line:
If mono therapy does not control symptoms, and poor ventricular rate control - use combination therapy of two of beta blocker, diltiazem digoxin
When should rhythm control be used to manage AF?
Consider rhythm control if:
Rate control is not successful
Symptoms persist after heart rate controlled
What is involved in rhythm management of AF?
Options are:
Cardioversion
Ablation
Drug treatment
What is involved in cardioversion for rhythm control?
For AF persisting longer than 48 hours - use electrical cardioversion not pharmacological
Consider amiodarone pretreatment 4 weeks before for up to 12 months after cardioversion
50% recurrence at 12 months
When should ablation for atrial fibrillation be used?
Paroxysmal - if drug treatment has failed
Persistent - use pacing and ablation
70% success rate - may require multiple procedures
2-3% major complication
Which drugs can be used for rhythm control?
Beta blockers other than sotalol
Dronedarone - maintains sinus rhythm after successful cardioversion
Amiodarone - if LVF or HF
Flecainide - pill in pocket - for infrequent paroxysmal AF with precipitants
Which anticoagulants can be used for thromboprophylaxis in HF?
Apixaban
Dabigatran
Rivaroaxaban
Warfarin
Use these (except warfarin) for non- valvular AF with other risk factors for stroke
What score should be used to assess need for oral anticoagulation in patients with AF?
CHADS2VASC
What are the components of CHADS2VASC?
CHF or LVEF Age >75 Diabetes Stroke/TIA Vascular disease Age 65-74 Sex category (female)
What components of CHADS2VASC score two points?
Age >75
Previous stroke /TIA
All the rest score one point
At what CHADS2VASC score should oral anticoagulation be offered?
> /= 2 - offer oral warfarin, Apixaban etc
> /= 1 - consider oral anticoagulation
0 - do not offer anticoagulation and do not use aspirin as an anticoagulant
What score can be used to asses risk of haemorrhage for patients with AF on anticoagulants?
HASBLED
What are the components of HASBLED?
Hypertension Abnormal liver or renal function (1pt each) Stroke Bleeding Labile INRs Elderly (age >65) Drugs or alcohol (1pt each)
What HASBLED score indicates increased risk of bleeds?
> /= 3 indicates increased one year bleed risk in anticoagulants, sufficient to justify caution or review
When should a patient with AF be admitted to hospital?
Very rapid pulse (>150bpm)
Very low BP (sys <90)
LOC, dizziness, chest pain, SOB
Complication - stroke, TIA, HF
When should a patient with AF be routinely referred to a cardiologist?
Age <50
Paroxysmal AF
Uncertainty regarding rate or rhythm control
Valvular disease, WPW, prolonged QT
When do cardioverted patients need to be monitored?
1 month and 6 moths after heart rhythm is back to normal
When do patients on long term anticoagulation need to be monitored?
INR checked daily until in therapeutic range
INR checked biweekly for 1-2 weeks
INR checked weekly until stable
INR checked every 6-12 weeks from stable
What bloods should be done when investigating AF?
FBC UandEs LFTs TFTs Clotting
Consider CXR
What lifestyle changes may help AF?
Stop smoking - risk factor for vascular disease as well as precipitants for AF
Alcohol in moderation - may precipitate AF
Caffeine may precipitate AF
