Atrial Fibrillation/Flutter Flashcards
What is atrial fibrillation?
Arrythmia (irregular heartbeat) characterisied by rapid, chaotic, and ineffective atrial electrical conduction
What are the groups of causes of atrial fibrillation?
- No identifiable cause (‘lone’ AF)
- Systemic causes
- Cardiac causes
- Lung causes
What is the principle behind secondary causes of AF?
They lead to abnormal atrial electrical pathways resulting in AF
Systemic causes of AF?
- Thyrotoxicosis (hyperthyroidism)
- Hypertension
- Pneumonia
- Alcohol
Cardiac causes of AF?
Mitral valve disease Ischaemic heart disease Rheumatic heart disease Cardiomyopathy Pericarditis Sick-sinus syndrome Atrial myxoma (tumour)
Lung causes of AF?
Bronchial carcinoma
Pulmonary embolism
Who is AF most common in?
Elderly (~5% of 65+)
May be paroxysmal
Presentation of AF?
Often asymptomatic
Some patients experience palpitations or syncope
Symptoms are mostly those of the cause
Examination findings in AF?
Irregularly irregular pulse
Difference in apical beat and radial pulse
Potential exam findings of thyroid disease and valvular heart disease
Investigations indicated in AF?
ECG
Bloods
Echocardiogram
ECG findings in AF?
Uneven baseline (fibrillations) with absent P waves and irregular QRS complexes
Which blood tests are indicated in AF?
Cardiac enzymes TFTs Lipid profile U&E Mg2+ Ca2+ - last 2 could be digoxin toxicity - raised digoxin conc + hypokalaemia/hypomagesaemia/hypercalcaemia
Potential findings on echocardiogram in AF?
Mitral valve disease
Left atrial dilation
Left ventricular dysfunction
Structural abnormalities
Management stages of AF?
Treat reversible causes (e.g. thyrotoxicosis, chest infection)
- rhythm control
- rate control
- thromboembolism prophylaxis
Methods of rhythm control in AF?
Cardioversion - DC or chemical (flecainide or amiodarone)
- anticoagulate first if >48 hrs after onset
- don’t use flecainide if Hx of ischaemic heart disease
