Atrial Fibrillation Flashcards
Define Atrial fibrillation.
Characterized by rapid, chaotic and ineffective atrial electrical conduction.
Often subdivided into: ‘permanent’, ‘persistent’ and ‘paroxysmal’
Describe electrical activity in the heart during atrial fibrillation.
Disorganised atrial electrical activity which is transmitted to ventricles via AV node.
Ventricular electrical activity shows characteristic irregular rhythm.
What can cause atrial fibrillation?
Many causes including ischaemic heart disease, hypertension, valvular disorders, electrolyte imbalance, sepsis, pericardial and myocardial disease, thyrotoxicosis and PE.
How would you manage a patient with AF?
Underlying cause actively sought and managed.
If patient is hypotensive with ventricular rate of >150bpm specialist help should be obtained.
?Cardioversion.
In px with significant structural heart disease pharmacological rate control with digoxin and beta blockers is more appropriate.
Low dose aspirin young with structurally normal hearts.
Full anti-coagulation with warfarin if px have significant risk factors for vascular disease or structurally abnormal hearts.
Long standing atrial fibrillation requires decision as to whether goal is rhythm control or rate control (establishing and maintaining sinus rhythm vs ventricular rate)
Who is appropriate for cardioversion and how can it be achieved?
If patient is not compromised and onset of AF was less than 24hr ago cardioversion is appropriate.
- achieved pharmacologically (eg with amiodarone or flecanide)
- or electrically by DC cardioversion.
- -Attempting electric DC cardioversion in px with AF >24hr increases risk of embolic stroke.
What is the main risk for patients with AF?
Ischaemic stroke.
Occurs in approximately 5% per year.
What is atrial flutter?
Similar to atrial fibrillation in aetiology, sequalae and management.
In atrial flutter atrial activity is organised but rapid.
“Saw tooth pattern”
Regular QRS complexes
