W3 Clinical management of Atrial Fibrillation Flashcards
What is an arrhythmia?
Abnormal rate and/or rhythm of heartbeat
Too fast (TACHYcardia), too slow (BRADYcardia) or irregular
“Usual” heart rate is 60-100bpm at rest
What are some common arrhythmias? (4)
- Ectopic beats – common and usually harmless
- Atrial fibrillation (AF) the most common sustained abnormal heart rhythm seen in practice – affects around 1 million people in the UK
- Atrial flutter
- Ventricular tachycardia (VT) – regular but fast heart rate
- Ventricular fibrillation (VF) – most common life-threatening arrhythmia
What are the 4 types of AF?
- Paroxysmal AF - episodes come and go, and usually stop within 48
hours without any treatment - Persistent AF – each episode lasts for longer than seven days (or
less when it’s treated) - Long-standing persistent AF – continuous AF for a year or longer
- Permanent AF – present all the time
^ All have the same risk of stroke
What are the symptoms of AF? (6)
- Can be asymptomatic – especially in older people
- Palpitations
- Tiredness
- Breathlessness/dyspnoea
- Syncope*/dizziness
- Chest pain/discomfort
Will also be suspected if someone has had a stroke or TIA
Syncope=fainting/passing out
dyspnoea- DIB
Prognosis of AF: (severity of disease)
What can AF lead to? (2)
Prognosis generally good with treatment – not usually life-threatening on its own
Can cause heart failure as ventricles work too hard and enlarge
Can lead to stroke
What are the Goals of management of AF? (3)
- To establish the diagnosis of atrial fibrillation
- To control and prevent symptoms (by controlling ventricular rate or atrial rhythm)
- To prevent stroke
Treatment of AF
What are the aims?
(for info)
- Admit if necessary (stroke or heart failure)
- Identify and manage underlying causes and triggers
- Rate control
- Rhythm control
- Stroke prevention
Rate control of AF:
What drugs are prescribed? (3)
What are their examples + adverse effects?
Recommended for most people (choice of drug class depends on co-morbidities and contraindications):
- Beta-blockers: atenolol, acebutolol, metoprolol, nadolol, oxprenolol, and propranolol (licensed), bisoprolol= most common
Adverse effects: bronchospasm, cold extremities, sleep disturbance/nightmares, fatigue, sexual dysfunction - Rate-limiting calcium-channel blockers: verapamil and diltiazem
Adverse effects: dizziness, palpitations, GI disturbances, bradycardia, lots of drug interactions - Digoxin monotherapy: in people with non-paroxysmal AF who are sedentary
Adverse effects: arrhythmias, blurred vision, conduction disturbances, diarrhoea, dizziness, eosinophilia, nausea, rash; vomiting, yellow vision
-toxic, narrow therapeutic index
-3rd time
Rhythm control (cardioversion)
Recommended in some people with new-onset AF (within 48 hours of presentation), especially with reversible cause, in HF worsened by AF or with atrial flutter.
Carried out in specialist care
Pharmacological cardioversion
Electrical cardioversion (esp. if pt. has had AF for longer than 48 hours)
Surgical cardioversion
What is Pharmacological cardioversion?
What are 2 medicines that can be used to treat AF and their consequent SE?
Treatment used to return an abnormal heart rate back to normal rhythm
- Flecainide (class lc antiarrhythmic) - IV loaded then oral dosing:
Adverse effects: asthenia, dizziness, dyspnoea, fatigue, fever, oedema, pro-arrhythmic effects, visual disturbances, lots of drug interactions
- Amiodarone (class III antiarrhythmic) – 200mg tds x7, bd x7, od
Adverse effects: bradycardia, hyperthyroidism, hypothyroidism, jaundice, nausea, persistent slate grey skin discoloration, phototoxicity, pulmonary toxicity (including pneumonitis and fibrosis), liver toxicity, reversible corneal microdeposits (sometimes with night glare), sleep disorders, taste disturbances, tremor, vomiting, lots of drug interaction
What is Electrical cardioversion?
Similar to external defibrillation
Patient sedated for short period of time
https://youtu.be/zC7yVk4yklA
Surgery:
What is Catheter ablation?
- Normally carried out via a vein in the groin (sometimes wrist)
- Area of heart causing abnormal electrical discharges destroyed with radiofrequency energy or cryotherapy
- If this is at the AV node, a pacemaker will be used in advance to restore sinus rhythm (“ablate and pace”)
https://www.youtube.com/watch?v=2cxztSBueDk
What are some examples of anticoagulants? (2)
- Direct-acting oral anticoagulants (DOACs)- now more common than warfarin
Direct thrombin inhibitor – dabigatran
Direct factor Xa inhibitors – apixaban, edoxaban, rivaroxaban - Vitamin K antagonists
warfarin, acenocoumarol, phenindione
What are DOACs? (or NOACs)
Examples?
Most common SE?
- Direct oral anticoagulants/New oral anticoagulants
- Apixaban,Dabigatran, Edoxaban, Rivaroxaban
- Now much more common than warfarin
- Standard dosing
- No monitoring of INR required
- A number of interactions have been discovered, and more being discovered
- Most common adverse effect is bleeding – more major GI than CNS
- Difficult to reverse the effects -idarucizumab for dabigatran, andexanet alfa for apixaban or rivaroxaban
What is checked at the annual review?
-Patient counselling:
- Adherence – short half-life so very important
- Specific dosing advice – keep dabigatran in packet, rivaroxaban take with food
- Missed doses – daily preps (riv, edox) take within 12 hours, bd (apix, dab) take within 6 hours
- Monitoring – inform of frequency and arrange
- Alcohol – stay within limits
- Bleeding – advise on signs and symptoms and emergency advice
- OTC - avoid aspirin/NSAIDs, St John’s wort
- Warning card – carry it and show it when receiving medical care
