Atrial fibrillation

Question 1

Pathophysio of AF

Answer 1

R/F:
Cardiac - CAD, valvular d/o, HTN
Non-cardiac - Obese, DM, Alc
Genetic

1. Stress (calcium overload)…
2. Cardiac cells - different electrical properties
3. Irregular local contractions in atria…
4. Few pass on to Ventricles…
5. REGULARLY IRREGULAR Ventricular contractions (90-170bpm)
6. ECG - atrial twitch, absent P, short QRS, irregular rhythm
7. Multiple waveform theory
   Automatic focus theory - around PV

Question 2

Symptoms, complications of AF

Answer 2

Low blood flow from heart
1. Fatigue
2. SOB
3. Palpitations

Complications:
Stagnant blood in atria…
BLOOD CLOTS formation
… brain … STROKE

Question 3

Rx of AF, score used?

Answer 3

CHA2DS2 VASc score - anti coagulant therapy
C: Congestive heart disease - 1
H: HTN - 1
A: Age =>75yrs - 2
D: DM - 1
S: Stroke/TIA/thromboembolism h/o - 2

V: vascular disease - 1
A: Age 65-75yrs - 1
Sc: Sex female - 1

0: Low risk, no need of anticoaglulants
1-2: mod risk, can consider
2: sev, needs

●No anticoagulation in
Male 0
Female 0/1

●Need anticoagulants
Male =>2
Female =>3

●Cardio referral for scores in between

Question 4

Mx of atrial fibrillation

Answer 4

ECG and TFT(thyroid)

●Rx of ppt factors

●Unstable - DC shock, Overdrive pacemaker

●Stable:
B-blocker, CCB …
Rhythm control - Sotalol, flecainide, Amiodarone

●Thromboembolism -
CHA2DS2 VASc score
Valvular AF - warfarin
●Drugs -
DOACS: Dabigatran, apixaban, rivaroxaban
Warfarin if renal failure+

●Radio-frequency catheter ablation
-Maze procedure
-AV node ablation
●Pacemaker insertion

Question 5

When do you use warfarin in AF

Answer 5

1. Valvular AF - Mitral stenosis/mechanical heart valve
2. CHADVASc score -
   Male =>2
   Female =>3

Question 6

Drugs for AF

Answer 6

●Anticoagulants:
DOACS: Dabigatran, apixaban, rivaroxaban
Warfarin if renal failure+

●Rate control/AV nodal block -
BB, CCB, digoxin,diltiazen
●Rhythm control/medical cardioversion -
Amiodarone, Flecainide

Question 7

Manage Atrial flutter

Answer 7

●MOST EFFECTIVE:
DC cardioversion (50J) if <48hrs
(Transesophageal ECHO before DCR for clots)

●If time cannot be established:
Rate control drugs
Anticoagulants (LMWH before warfarin)

●Maintenance:
Flecainide/Sotalol/Amiodarone + AV node blockers