2. Atrial Fibrillation (AF)
Most common sustained cardiac
arrythmia.
Present in 1% persons > 60 yrs of age.
Incidence and prevalence increases with
age.
Framingam data shows life time risk of
AF > 40 yrs of age 26%
3. Definition
• It is a supraventricular tachyarrhythmia characterized
by uncordinated atrial activation with consequent
deterioration of atrial mechanical function.
Types of AF
• Recurrent AF > Two episodes
Paroxysmal AF Resolve spontaneously
Persistent AF Sustained > 7 days.
Permanent AF 1 yr duration.
Lone AF Young individual (<60 yrs of age)
without clinical or echo evidence of cardiopulmonary
disease, including hypertension.
4. Mechanism
• 2 Mechanisms:
• enhanced automaticity in 1 or more
rapidly depolarizing foci
• reentry in 1 or more circuits
• Foci in superior pulmonary veins, RA,
SVC coronary sinus
5.
6. Causes of AF
Associated with organic heart disease
Coronary Heart disease
Hypertension
Valvular Heart disease
Cardiomyopathies
ASD
Chronic CHF
WPW
Myocarditis
7. Causes of AF
With normal hearts
Physiologic Stress
Pericarditis
Chest trauma
Thoracic / Cardiac surgery
Pulmonary disease
Medications
Thyrotoxicosis
Alcohol intake
Fluid / Electrolyte imbalance
Lone AF
9. ECG Manifestations
Small irregular baseline
undulations of variable
amplitude and morphology
called ’f’ wave.
Atrial rate
@ 350-600 bpm.
P waves absent.
Ventricular
Rhythm–Irregularly
irregular.
Rate - 100-160 bpm
10.
11.
12. Bad outcomes?
• Loss of synchronous mechanical activity
• Irregular ventricular response
• Rapid heart rate
• Decreased hemodynamic function
• Tachycardia-induced atrial cardiomyopathy
• Dilated ventricular cardiomyopathy (>130 bpm)
• Thomboembolism
13. Evaluation
• History
• Symptom : Shortness of breath, palpitation,
chest pain, fatigue (elderly)
• Underlying heart disease, hyperthyroidism,
alcohol consumption
• Blood test: Thyroid, renal and hepatic function.
For a first episode of AF when Ventricular rate is
difficult to control
14. • ECG:
• Rhythm
• LVH
• Preexcitation
• BBB
• Prior MI
• TTE
• Valvular heart disease, LA, RA size, LV
size and function, LVH, LA thrombus
(TEE)
17. Initial approach depend on each individual
• Rate control in older with persistent AF
with hypertension or heart disease
• Rhythm control In younger i.e.
paroxysmal lone AF
• 1st choice drug
• 2nd choice left atrial ablation (preferred
in young patients with highly
symptomatic AF).
• Patient for coronary bypass or wall surgery
COX maze III procedure (left atrial ablation)
is preferred.
18. Rate control
1. General rule
Asymptomatic patient with AF : rate control is sufficient (donot
require rhythm control)
Symptomatic Lessil Persistent or
(Hypotension permanent AF
Angina I.V. drugs to slow
Heart failure) ventricular rate blocker
Non DHP CCB
DC conversion No pre Accessory Digoxin (If HF or LVD)
excitation pathway +
I.V. blocker I.V. amiodarone
I.V. Non DHP's I.V. Digoxin
Drug ineffective Ablation of AVN or Accessory path
19. RHYTHM CONTROL
As a rule
• Pt. without structural heart disease IC (Propafenone and
flecainide) 1st line for maintenance
• Pt. with structural heart disease Amidaroine, sotalol
Symptomatic AF with preexcitation
hypotension (Very rapid tachycardia
Anigna, HF Hemodynamic instability
Ongoing myocardialischemia
DC-cardioversion DC cardioversion
20. PHARMACOLOGICAL CARDIOVERSION
• More effective within 7 days of AF
• Flecanide, dofetilide, propafenone, amiodarone
• Digoxin and sotalol not recommended
Selected patients with no
• SAN or AVN disease
• BBB
• QT prolongation
• Brugaa syndrome
• Structural heart disease
Propafenone (600 mg),
flecanide (200-300 mg)
(pill in pocket)
21. Maintenance of sinus rhythm
• Treat precipitating or reversible cause
• Sotalol : In out patients with sinus
rhythm with little or no heart disease.
22. Prevention of thromboembolism
• ACC/AHA guidelines recommend antithrombotic
therapy for all patients with AF. Except
• Lone AF
• Contraindication to antithrombotics
• AF > 48 hours or duration unknown
anticoagulation (INR 2-3) is recommended for at least 3
weeks prior to and 4 weeks after cardioversion,
regardless of the method (electrical or pharmacological)
• AF < 48 hrs emergency cardioversion should be
performed immediately without prior anticoagulation
23. Choice of therapy depends on patient's risk of
stroke and bleeding
Vitamin K antagonist Aspirin (81-325 mg OD)
> 1 risk factor In low risk patients
(> 65 yr, HTN, HF,
LVD, DM, CAD) Contraindication to anticoagulant
(> 75 yr, ICH)
24. Catheter ablation
• Pulmonary veins are an important source of ectopic beats,
initiating frequent paroxysms of AF and triggers as well as
circuits for spontaneous AF, can be the target of therapy.
• Focal PV isolation; linear ablation of right atrium, left atrium
or biatrial; circumferential PV ablation, and segmental PV
ablation.
Surgical ablation
• Maze cut and sew techniques.
• Bipolar radioferquency, cryoablation and microwave energy
have been used as alternatives to the cut-and sew technique.
25. Newly discovered AF
Paroxysmal Persistent
No therapy needed unless Accept permanent AF Rate control and
significant symptoms anticoagulation
(e.g., hypotension, HF, as needed
angina pectoris)
Anticoagulation as needed Anticoagulation Consider
and rate control anti-arrhythmic
as needed drug therapy
Cardioversion
Long-term anti-arrhythmic
drug therapy unnecessary
26. Recurrent Permanent AF
persistent AF
Anticoagulation and
rate control as needed
Minimal or Disabling
no symptoms symptoms in AF
Anticoagulation and Anticoagulation
Rate control as needed and rate control
AAD therapy
Electrical Continue anticoagulation
cardioversion as needed and therapy to
As needed maintain sinus rhythm
Consider ablation for severely
symptomatic recurrent AF after
failure of greater than or equal to 1
AAD plus rate control
