Transcript Atrial Fibrillation

Atrial Fibrillation
Dr Nidhi Bhargava
8/10/13
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Most Common sustained clinical
arrhythmia
Incidence rises with age- >5% over
the age 65-75
Risk factors for AF
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Hypertension- accounts for 14% of AF in population
Heart failure
Male sex
Diabetes
Valvular
MI
LVH
LVSD
Left atrial dilatation
Lone AF- with no structural or functional heart
disease- 15%
Types of AF
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Paroxysmal or recurrent (intermittent and
self terminating)
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35-66% of all AF cases peak prevalence 50-69yrs
At least a quarter may go progress to permanent AF
Persistent (does not terminate
spontaneously but may be effectively
cardioverted)
Permanent ( no longer reversible or reverses
for brief interval only)
Shortcut to Treatment startegy decsion tree.lnk
Effects of AF
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Haemodynamic effects
– Loss of atrial contraction and AV
synchrony
– Rapid ventricular rate
– Irregular ventricular rate
Effects of AF
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Symptoms
– Palpitations
– Breathlessness
– Chest pain
Effects of AF
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Thromboembolism
– Valvular AF -more so in pts.. with MS and
AF (6% per year)
– Non Valvular AF- 4-5 times increased risk
of stroke overall
– Further increased risk if
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Previous stroke or TIA (20x increased risk)
Age >65, Hypertension and diabetes
CAD, LV dysfunction and Left atrial dilatation
<65 yrs. risk 1% per annum
Effects of AF
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Mortality- doubled in both sexes
Increased risk of stroke 4-5 fold
increase- further increase with age
from 1.5% in sixth decade to 23.5% in
the ninth decade
Treatment
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Restoration of sinus rhythm
Pharmacological cardioversion
 Electrical cardioversion
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– External
– Internal
Treatment
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Maintenance of sinus rhythm
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Drugs
DDD pacing
Ablation of AF triggers
Surgery for AF
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Ventricular Rate Control
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Anticoagulation
Treatment
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Cardioversion (pharmacological and electrical)
– Electrical cardioversion
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External and Internal
External- under GA, success rate 65-90%, 200-360J
Internal- under sedation- percutaneous electrode- success
rate 90%
– Pharmacological cardioversion
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Most effective if administered within 24 hrs. of onset
Flecainide most effective- 72-95%
Others include amiodarone , sotalol, propafenone
Less effective in chronic AF- Amiodarone most effective
At least 4 weeks of full anticoagulation
Anticoagulation to e maintained for 4 weeks after successful
cardioversion
Treatment
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Maintenance of Sinus rhythm
– Drugs
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Flecainde and Propafenone (Class 1c)
Sotalol better then propafenone
Amiodarone – most effective but multiple side
effects
Beta blockers- no date available
Digoxin- no effect
– Pacing
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DDD pacing- reduce AF paroxysms
Continuous atrial pacing-dual site or biatrial
Treatment
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Focal Ablation
Targets AF initiating foci located in proximal
pulmonary veins
 Radiofrequency energy delivered
 Used for pts. with paroxysmal AF
 Pts. with chronic AF but can be successfully
cardioverted at least for few seconds
 Under LA
 Success rate 70% in PAF and 50% in chronic
AF
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Treatment
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Surgery for AF-Maze operation
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Ventricular rate control
AV node ablation
 Drugs
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Digoxin- not negative inotropic but less
effective
Diltiazem, verapamil and beta blockers- more
effective but negatively inotropic
Case histories
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A 67 years old female with no risk factors presents with palpitations
A 77 years old male with no risk factors is found to be in AF on
routine examination
A 98 years old male with AF on warfarin presents with haematuria
and subsequently diagnosed with Ca bladder
A 79 year old female with AF rate 120-140/min, on warfarin and
digoxin, asthmatic and has severe reaction to verapamil-treatment
options
A 64 years old diabetic is in AF on routine examination