5. AF Flashcards
what is atrial fibrillation?
heart condition that causes an irregular and abnormally fast heart rate.
what is normal heart beat range at rest?
60-100bpm at rest
what are the causes/risk factors for AF ?
Cardiovascular diseases
Hypertension
Heart failure
Ischemic heart disease
Mitral valve disease
Congenital heart disease
Coronary heart disease
Pericardial disease
cardiomyopathy
what are the causes/risk factors for AF ?
pulmonary conditions
Pulmonary embolism
Pneumonia (common)
Bronchial Carcinoma
Covid
Lung cancer
COPD
what are the causes/risk factors for AF ?
(other then cardiovascular and pulmonary)
Age
Obesity
T2DM
Overconsumption of alcohol
Hyperthyroidism → thyrotoxicosis
Overconsumption of caffeine (stimulants)
Physical stress due to surgery (post-op)
Atherosclerosis
Sepsis
Electrolyte disturbances Mg2+
Smoking
sleep apnoea
Genetic factors/family history
chronic kidney disease, CKD
A patient presents with palpitations
what tests should you order?
ECG
might need 24 hour one to pick up episodes of AF
bloods
could also do an echocardiogram to see any structural heart disease
how does an AF ECG present?
No P waves, irregular baseline
Irregular QRS
blood test:
what specific tests are done?
testing to find underlying causes of AF + to see if safe to go on medication
U+Es for renal dysfunction
TFTs for hyperthyroidism
LFTs for alcoholism and contraindications with medication
CMP (calcium,magnesium,phosphate) for electrolyte disturbances
glucose for T2DM
describe the pathophysiology of AF
- cells in the atria are stressed (by risk factors)
- leads to tissue heterogeneity (cells start taking on different electrical properties eg. some can conduct faster than others)
- Leads to unpredictable conduction in the atria.
- the random elective impulses firing off muscle in the atria override the natural pacemaker
- Atria quiver randomly and only partially contract
Haphazard and random impulses pass through to the ventricles causing irregular ventricular contractions with varying force
what are the different types of AF?
Paroxysmal AF – AF comes and goes, tissue still healthy, usually within 2 days goes back to normal heart rate and rhythm
Persistent AF – Lasts over a week without self-terminating. cells have undergone fibrosis
Permanent AF – Long term, heartbeat beat does not return back to normal even after treatment
symptoms of AF
palpitations in chest (thumping)
General fatigue (irregular contractions delivers blood less effectively to tissues)
Dizziness
Shortness of breath
Weakness
asymptomatic
what is the main complications of AF?
major risk of stroke
if palpations continue, stagnant blood in atria can clot, travel to brain and lodge
(other complications: quality of life reduced as can’t exercise much, angina, HF)
what are the treatment options for AF? (4 categories)
rate control treatment
rhythm control treatment
ablation
medication to decrease risk of clots and strokes
the treatment options for AF
- what medication is used to control heart rate?
Beta blockers and Calcium channel blockers to Interfere with electrical impulses
the treatment options for AF
- what method is used to control heart rhythm ?
and what medication can also be taken for rhythm
cardioversion
- give heart an electric shock
Medication to convert heart rhythm eg. amiodarone, Flecainide
the treatment options for AF
- what its ablation?
Pass a long thin catheter into chambers of heart and destroy tiny sections of tissue (using radio frequency) that are responsible for irregular impulses
AF can cause serious strokes
what tool is used to assess the risk of stroke in an AF patient?
CHA2DS2-VASc risk score
CHA2DS2-VASc risk score
- what does it CHA2DS2-VASc stand for? what questions does it ask
Congestive heart failure (1)
Hypertension (1)
Aged over 75 (2)
Diabetes (1)
stroke history (2)
Vascular disease (1)
Aged 65-74 (1)
Sex female is (1) men (0)
CHA2DS2-VASc risk score
what score means treatment for risk of stroke is needed?
2 or above
how is risk of stroke in AF patients treated?
anticoagulants
- aspirin
- warfarin
- DOACs
what are DOACs ?
direct-acting oral anticoagulants
eg. Dabigatran,
Apixaban,
why are DOACs now preferred over warfarin?
effective and carry a lower risk of bleeding into the brain
Have fewer interactions with other drugs or food (no special diet needed)
Need less blood monitoring (patient doesn’t need to come in for as many tests, less adjustments needed)
what tool is used to asses risk of major bleeding?
Use in adult patients with atrial fibrillation, to assess risk of major bleeding with anticoagulation (for stroke prevention)
ORBIT score
what’s a pitfall of the ORBIT score calculator?
does not take into account choice of anticoagulant.
what are the risk factors that ORBIT score evaluates ?
AGE - older then 75
reduced haemoglobin or history of anameia
bleeding history
insufficient kidney function
are they on antiplatlet treatment
why is it important to know if a patient has reduce haemoglobin or anaemia when thinking of putting them on anticoagulants ?
need to know if they have any bleeding or haemorrhages eg. in brain or GI tract
because it you gave anticoagulant that would dangerously exacerbate and cause fatal bleeding
( 2 major risks of anticoagulants =GI bleed andbrain haemorrhage )
what tests could you order when assessing a patients ORBIT score ?
GFR - for kidney function
FBC - for haemoglobin
