Week Seven - Case Two Flashcards
how can atrial fibrillation only be confirmed
with an ECG demonstrating an irregularly irregular RR interval and absent or abnormal P waves
according to the British Heart Foundation statistics, how many patients have been diagnosed with AF in the UK
1.5 million
what is the biggest risk with AF
stroke
what is the definition of sustained absent P waves
more than 30 seconds
why does the irregular RR interval happen
af is disorganised electrical activity within the atria. this gives rise to absent or abnormal P waves. the AV node is usually unable to conduct at such rapid rates and consequently there is a degree of AV block.
during AF the ventricular conduction is random and hence it gives rise to the irregularity of the ventricular beats (irregular RR interval)
what is one of the major mechanism triggers of AF
pulmonary vein ectopy.
in AF patients, during embryonic development, sleeves of atrial tissue abnormally extend into the pulmonary veins. Ectopy arising from cardiomyocytes within one or more pulmonary veins can enter the left atrium and trigger AF, as well as sustain the arrhythmia
what sort of heart failure can AF result in
it can impair the heart function and result in HF with reduced left ventricular systolic function.
what is tachycardiomyopathy
The relationship between AF and heart failure is like the “chicken and the egg”. In some patients the AF drives the heart failure and is the sole cause (called “tachycardiomyopathy” or “tachycardia-induced cardiomyopathy”). It is usually reversible once the AF is controlled or sinus rhythm restored. In other patients the AF is merely a consequence of the heart failure. Often AF can exacerbate pre-existing heart failure causing decompensation.
what are the three important aspects of AF management
stroke prevention
symptom control
risk factors and comorbidities
what is the most common tool used to assess stroke risk
CHA2DS2VASc
if patients are at a high risk of stroke what should they be offered
anticoagulation
what is important to assess before starting anticoagulation and what is the score used for this
bleeding risk before starting anticoagulation
the score systems used are HASBLED or ORBIT score
what score on the HASBLED would require frequent monitoring
patients with a HASBLED score of 3 or more may be deemed high risk and require close monitoring.
what is recommended to patients with a high risk of stroke
oral anticoagulation
what CHA2DS2VASc score is deemed as high stroke risk
score of 2 or more in women, and score of 1 or more in men
what anticoagulants are used first line in patients with increased stroke risk
DOACs recommended first line
what is Apixiban only licensed for use in
patients with CKD who need oral anticoagulants
what do patents with heart failure and AF benefit from
an early rhythm control strategy with randomised control studies showing improved mortality following catheter ablation
what medications are used for rate control in AF patients
beta blockers
what medications are used to maintain sinus rhythm in AF
Amiodarone and flecainide
what surgery is used to maintain sinus rhythm
catheter ablation (pulmonary vein isolation ablation)
what else can be given
a permanent pacemaker plus AV node abalation
what is the most effective way of restoring sinus rhythm
cardioversion however it does not prevent the recurrence of AF
what is defined as an unsuccessful DC cardioversion
the inability to restore sinus rhythm even for one beat despite at least 4 weeks of Amiodarone therapy
what does non sustained mean
less than 30s duration
what does long standing persistent mean
more than one year
what does paroxysmal mean
between 30 seconds and up to one weekw
what does persistent mean
more than one week
what does sustained mean
more than 30 seconds
what are the treatment options for AF and rapid ventricular response
incude rate control versus rhythm control