Atrial fibrilation

Question 1

What is atrial flutter?

Answer 1

When the atria beats too fast but is rhythmic

Question 2

What is the biggest danger in AF?

Answer 2

During AF, the atria is firing impulses from everywhere in the atria 400 time a second = isn’t contracting and ejecting blood properly so blood pools in the atria = risk of clots = risk of stroke

Question 3

What would be missing on the ECG during AF?

Answer 3

P wave

Question 4

What are the 4 types of AF?

Answer 4

1. ) Paroxysmal - episodes come and go, don’t last longer than 48hrs
2. ) Persistent - episodes that last longer than 7 days (without treatment)
3. ) Long-standing - continuous AF for more than a year
4. ) Permanent - present all the time - can’t be treated.

Question 5

What are the symptoms?

Answer 5

Often asymptomatic - put it down to old age

1. ) Breathlessness
2. ) Palpitations
3. ) Tiredness
4. ) Dizziness
5. ) Chest pain

Question 6

Who are most at risk?

Answer 6

Women over 65 who have HT, atherosclerosis, heart valve issues

Question 7

If left untreated what can AF lead to?

Answer 7

Heart failure - ventricles work too hard = become enlarged

Stroke

Question 8

How do we diagnose AF?

Answer 8

ECG - if paroxysmal will have to wear for 24hrs

After diagnosis will have and echo to see the damage and enlargement

Question 9

What are the three classes of drug involved in RATE CONTROL in AF? (control ventricular beating)

Answer 9

1. ) Beta-blockers
2. ) Rate-limiting CCB’S = dilatazem and verapamil (not the ones used in HT)
   3) Digoxin monotherapy

Question 10

Who is digoxin monotherapy suitable for?

Answer 10

People with permanent AF and who are sedentary - digoxin slows the heart down permanently = if did any exercise would collapse.

Question 11

What are the three types of RHYTHM CONTROL (cardioeversion)?

Answer 11

1. ) Pharmacological carioeversion
2. ) Electrical cardioeversion
3. ) surgical cardioversion

Question 12

who is rhythm control recommended for?

Answer 12

1. ) New onset AF
2. ) Reversible cause
3. ) People with HF that is getting worse bc of AF
4. ) Atrial flutter

Question 13

What drug groups are involved in pharmacological cardioeversion?

Answer 13

1. ) Voltage gated Na+ channel blockers - FLECANIDE
2. ) beta blocker - SOTALOL
3. ) K+ channel blocker - AMIODARONE

Question 14

What is electrical caridioeversion?

Answer 14

Like defibrillation. If not done within 48hrs of presenting symptoms need to administer anticoagulant first. Mild irritation but will recover quickly. Will resolve problem for long period of time, permanently in some people.

Question 15

What is surgical cardioeversion?

Answer 15

A catheter is put through the groin and into the heart. Identify where the problem is and kill this part of the heart via radiofrequency or chryotherapy (freezing).
in people with permanent AF OR WHERE ELECTRICAL HASN’T WORKED

Question 16

What happens before surgical cardioeversion if the part causing the problem is near the AV node?

Answer 16

A pacemaker must be fitted

Question 17

What extra drug class should most AF patients be on?

Answer 17

Anticoagulants - risk x5 in people with non-rheumatic AF. risk is x17 if is rheumatic i.e. another disease affecting the valves

Question 18

If you have AF how many points do you have to score (CHA2DS2-VASc) to be offered an anti-coagulant?

Answer 18

2

Question 19

Why would an anti-platelet like aspirin not be offered in AF?

Answer 19

Not good at preventing strokes and has a high risk of causing bleeds

Question 20

What two scores need to be balanced before an anticoagulant can be offered

Answer 20

CHA2DS2-VASc vs HAS-BLED

= RISK OF STROKE Vs risk of bleeding

Question 21

What two classes of anticoagulants were made to try and overcome the problems associated with vitamin K antagonists?

Answer 21

NOACS (non-vitamin K antagonists_
DOACS ( direct acting oral anticoagulants) : either directly inhibit thrombin through 2A (dabigatran) or directly inhibit factor xa (rivaroxaban)

Question 22

What factors in the clotting pathway does warfarin inhibit?

Answer 22

All of them

Question 23

What are the disadvantages of warfarin?

Answer 23

1. ) Interacts with everything
2. ) Have to have regular INR tests to check how well blood is clotting
3. ) Can be difficult to find initial loading dose
4. ) Risk of bleeding in CNS (but easily monitored and reversed)

Question 24

why can we not measure INR for NOACS and DOACS?

Answer 24

only act on factorr Xa or thrombin - we can’t measure at these parts of the pathway

Question 25

What are the advantages of the NOACS AND DOACS?

Answer 25

Don’t interact with quite as much - mostly renally cleared = doesn’t go through the liver
Don’t have to go for regular INR tests
Same dose is taken everyday - don’t have to change

Question 26

What are the disadvantages of the NOACS AND DOACS?

Answer 26

1. )Have a shorter half-life = if miss a dose if non-adherant won’t be protected against stroke
2. )More risk of accumulation and bleeding (in GI) as can’t monitor and tell if you are bleeding
3. ) Difficult to reverse its effects if you do bleed - monoclonal antibody = new and very expensive

Question 27

What is used to reverse small bleed on warfarin?

Answer 27

Vitamin K = INCREASE CLOTTING FACTORS

Question 28

what is the target INR and what are we balancing?

Answer 28

2.5 (range is 2-3)

The risk of bleeding (high INR) and the risk of clotting (low INR)