AFib

Question 1

pathophysiology?

Answer 1

• atrial ectopic beats (automaticity foci) thought to originate in pul veins –> lead to uncontrolled contraction of atria & irregular, fast, fibrillatory activity (300-600bpm) which also leads to irregular contraction of ventricles
• due to the irregular contractions, atria fail to empty adequately & blood pools there–> risk of clot formation

Question 2

symptoms?

Answer 2

• often asymptomatic
• dizziness
• palpitations
• SOB
• collapse

Question 3

signs?

Answer 3

• irregularly irregular pulse
• pulse deficit
  
  • fast AF–> loss of diastolic filling –> no detectable pulse
• signs of LVF

Question 4

DDx for irregularly irregular pulse?

Answer 4

• AF
• Ventricular ectopics

can be differentiated w ECG

Question 5

what are ventricular ectopics & how do they present?

Answer 5

• premature ventricular beats caused by random electrical discharges from outside atria
• presents as random, brief palpitations
• disappear when HR gets over a certain threshold

Question 6

aetiology of ventricular ectopics

Answer 6

• common at all ages and in healthy patients
• more common if pre-existing heart condition

Question 7

diagnosis of ventricular ectopics?

Answer 7

individual random, broad QRS complexes on the background of a normal ECG

Question 8

Ix & findings on ECG?

Answer 8

• Bloods
• ECG
  
  • no P waves
  • narrow QRS
  • irregularly irregular ventricular rhythm
  • undulating baseline

Question 9

classification of AF

Answer 9

• valvular
  
  • moderate/severe MS too
• non-valvular
  
  • any other valvular pathology or none at all

Question 10

aetiology? mnemonic

Answer 10

MRS SMITH

Sepsis

Mitral valve pathology

IHD

Thyrotoxicosis

Hypertension

also…

• Lung disease- PE/Pneumonia
• Alcohol
• ASD

Question 11

complications?

Answer 11

• risk of stroke
  
  • clot embolise to brain–> ischaemic stroke
• HF due to poor filling of ventricles
• sudden death

Question 12

types of AF?

Answer 12

• paroxysmal
• persistent
• permanent

Question 13

what is paroxysmal AF

Answer 13

• recurrent episodes
• terminates spontaneously within 7 days

Question 14

what is persistent AF?

Answer 14

lasts >7 days, requires termination by pharamcological or electrical cardioversion (may still recur after this)

Question 15

what is permanent AF?

Answer 15

• refractory to cardioversion
• sinus rhythm cannot be restored or maintained
• AF is accepted as final rhythm

Question 16

main principles of Rx

Answer 16

• rate /rhythm control
• anticoagulation

Question 17

Mx of paroxysmal AF

Answer 17

Rx: pill in pocket (flecainide) + anticoagulation

prevention: beta blocker/amiodarone/sotalol

Question 18

Mx of acute AF (<48h)

Answer 18

• haemodynamically unstable
  
  • emergency electrical cardioversion
• no haemodynamic instability
  
  • Rate control (or rhythm control)
    
    • aim is <100bpm
  • if no spontaneous conversion to sinus rhythm:
    
    • start LMWH
    • immediate cardioversion (electrical or pharmacological)

Question 19

Mx of persistent AF?

Answer 19

1. rate control, unless
   
   • reversible cause for AF
   • AF is of new onset
   • AF is causing HF
   • they remain symptomatic despite being effectively rate controlled

if any of above circumstances, offer rhythm control

Question 20

options for rate control?

Answer 20

1. beta blockers- metoprolol
2. rate limiting CCB - Verapamil
   
   • not preferable in HF
3. Digoxin
   
   • only in non-paroxysmal AF & if sedentary

Question 21

options for rhythm control?

Answer 21

• cardioversion
  
  • immediate vs delayed
  • elctrical vs pharmacological
• long-term medical rhythm control

Question 22

other options, when drug treatment has failed?

Answer 22

• radiofrequency ablation of AV node
• maze procedure
• cardiac pacing

Question 23

what should be given 4 weeks before electrical cardioversion & up to 12 months after?

Answer 23

amiodarone therapy

Question 24

if AF>48h, what is preferred route of cardioversion?

Answer 24

electrical

Question 25

by how much does anti-coagulation reduce risk of stroke in AF?

Answer 25

by 2/3

Question 26

tool for assessing whether patient with AF needs to be started on anti-coagulation?

Answer 26

C- Congestive HF Hypertension A2- Age\>75 ( score=2) Diabetes S2-Stroke or TIA previously (score=2) Vascular disease Age 65-74 Sex (female)

Question 27

who does NICE recommend should start anti-coagulation?

Answer 27

in ALL pts with score 2 or more * to be considered in men score \>1 * women with a score of 1 due to gender = not an indication for treatment

Question 28

assessment tool for assessing someone's risk of bleeding whilst on anti-coagulation?

Answer 28

HT Abnormal liver /renal function Stroke Bleeding Labile INRs Elderly Drugs /alcohol

Question 29

what anti-coagulants are given in AF?

Answer 29

* warfarin * NOAC if above contra-indicated: dual anti-platelet therapy

Question 30

what anti-coagulants are given post stroke?

Answer 30

warfarin or direct thrombin/factor Xa inhibitor