Atrial fibrillation (AF) Flashcards
What is atrial fibrillation?
When atrial contraction is irregular and uncoordinated due to disorganised electrical activity that overrides the normal activity of the SA node. The AV node responds intermittently which causes an irregular ventricular rhythm too.
Comment on the rhythm and QRS complex seen in AF
Irregularly irregular rhythm, irregular/narrow QRS complex
1) Name 2 causes of AF
2) Name 2 symptoms of AF
3) Name 2 signs of AF
1) HF, IHD, hypertension, PE, mitral valve disease, pneumonia, hyperthyroidism, hypokalaemia
2) chest pain, palpitations, shortness of breath, syncope/faintness, excessive alcohol consumption
3) Irregularly irregular pulse, 1st heart sound of variable intensity, apical pulse rate greater than the radial pulse rate
1) As Well as an irregular QRS complex, what else may be seen on an ECG of a patient with AF?
2) AF is considered an irregularly irregular pulse, and there are 2 differential diagnosis for an irregularly irregular pulse - what is the other one?
3) How can these 2 be distinguished from each other?
1) Absent P wave
2) Ventricular ectopics
3) Ventricular ectopics disappear when the HR gets over a certain threshold therefore during exercise, a regular HR suggests ventricular ectopics – not AF
1) What is the approach used to treat paroxysmal AF?
2) What does this this approach involve?
3) What are the 2 conditions that must be met in order for this treatment to be appropriate?
4) What is the usual medication given?
5) In what condition (associated with AF) should this medication be avoided in?
1) ‘Pill in the pocket’
2) Taking a pill to terminate AF when a patient feels the symptoms starting
3) Intermittent AF, no underlying structural heart disease
4) Flecainide
5) Atrial flutter
Rate control in the management of AF
1) In rate control management of AF, why is the aim is to decrease HR to under a 100bpm?
2) What are the 3 occasions when rate control is NOT the 1st line management for AF?
3) What is the 1st line rate control drug?
4) What is the 2nd line rate control drug, and in what condition is this drug not preferable in?
5) What is the 3rd line rate control drug, and in which group of people is this prescribed in?
1) To prolong the time the heart is in diastole for, to increase ventricular filling
2) When there’s a reversible cause of AF, there’s new onset AF or if AF is causing HF
3) Beta blocker i.e. atenolol
4) CCB i.e. diltiazem. HF
5) Digoxin. Sedentary people
Rhythm control in the management of AF
1) As well as the 3 occasions where rate control is NOT the 1st line management for AF, what is the other occasion when rhythm control is offered to patients?
2) In what scenario would cardioversion as a method for rhythm control be immediate?
3) In what scenario would cardioversion as a method for rhythm control be delayed, and what is important in such scenario?
4) What is the 1st choice drug for pharmacological cardioversion, and what is the 2nd choice and when would it be used?
5) What type of electrical cardioversion can be used - synchronised ot unsynchronised?
6) What group of drugs is the 1st line treatment for long term rhythm control?
7) What drug is the 2nd line treatment for long term rhythm control, and when is it used?
8) What drug is the 3rd line treatment for long term rhythm control, and specifically which group of patients is this drug most useful in?
1) They remain symptomatic despite being effectively rate controlled
2) AF present for <48hrs
3) AF present for >48hrs. Patient should be anticoagulated for a minimum of 3 weeks prior
4) Flecainide, amiodarone - used when patient have structural heart disease
5) Synchronised
6) Beta blockers
7) Dronedarone. When patients have had successful cardioversion
8) Amiodarone. Patients with HF or left ventricular dysfunction
Anticoagulation in AF
1) Why are patients with AF at a higher risk of getting a stroke?
2) What score is anticoagulation in AF based on, and when does this indicate anticoagulation?
3) What 2 drugs/groups of drugs can be used for anticoagulation, and which of these is 1st line?
4) What kind of drug is warfarin and how does it work?
5) Name an advantage of DOACs over warfarin
1) Uncontrolled movement of the atria leads to blood stagnating in the left atrium, particularly in the atrial appendage, and this can lead to a thrombus formation, which can lead to an ischaemic stroke
2) CHA2DS2-VASc score. When 1 or more of the features are present
3) Warfarin and DOACs i.e. apixaban, dabigatran, rivaroxaban. DOACs = 1st line
4) Vitamin K antagonist which is important for the function of many clotting factors. Warfarin therefore prolongs the prothrombin time
5) No monitoring required, no major interactions, equally/slightly better at stroke prevention in AF and equally/slightly less risk of bleeding than warfarin
