AF and HF

Question 1

Rate of AF in HF

Answer 1

Increases with severity of HF

• 10% in mild
• 25% in moderate
• 50% in severe

Question 2

RF of AF and HF

Answer 2

• Age
• HTN
• DM
• IHD, VHD

Question 3

AF and CO

Answer 3

• Increased HR at rest
• Increased HR response to exercise
• Shorter diastolic filling time
• Less CO

Question 4

AF and myopathy

Answer 4

• Tacharrhythmias induce cardiomyopathy

- ~50% of those with AF and LV dysfunction have some element of tachycardia induced myopathy

Question 5

Treating Tachyarrhythmia- pros and cons

Answer 5

• Ablation can cause reverse remodelling in some patients
• Some anti arrhythmic drugs are +ve inotropes
• Some are -ve

Question 6

HF and risk of AF

Answer 6

Increased in several ways:

• Increased chamber filling pressures
• Poorly regulated [Ca]i
• Neuroendocrine dysfunction (Structural remodelling/atrial fibrosis)
• Interstitial fibrosis

Question 7

Treating AF

Answer 7

Rate vs Rhythm control
- Evidence unclear for benefit of rhythm control but studies where sinus rhythm actually maintained show benefit

Rate Control
- B-blockers (slow rate and lower mortality)

• non-dhpd CCB (but -ve inotropy may not be tolerated)

Question 8

Anti-arrhythmic drugs

Answer 8

Class Ic
- Flecainide, encainide are considered to have high risk of mortality in these patients

Class III

• Amiodarone (KCB)
• some functional overlap w/ Class I (B-blockers) and CCB

Statins
- Shown to reduce AF in its with HF