The Commonest Arrhythmia

1. ATRIAL FIBRILLATION
Dr SYED RAZA
MD,MRCP(UK),CCT(UK),MESC,Dip.Card(UK),FCCP
Consultant Cardiologist

3. OBJECTIVES
• Introduction
• Classification
• Burden of the problem
• Diagnosis
• Management

4. What is it ?
• Abnormal electrical wavelets originate from
left atrium
• Propagating in different directions
• Disorganized atrial depolarisation without
effective atrial contraction

6. DIAGNOSIS
• Pulse palpation
• 12 lead ECG
• Holter monitoring
• Others
• Echocardiogram, CXR
• TFT, Electrolytes, Clotting, LFT,CBC

8. ECG Diagnosis
• On ECG p waves are absent and RR interval is
variable.
• f waves 350-600 beats /min.
• ventricular response is grossly irregular at
100-160 beats /min.
• Rate : No. of R waves x 10 ( 6 sec strip)

11. Prevalance
• 2.2 Million people in the US
• 6.5 cases/1000 examinations
• 4% > 60yrs
• 8 % > 80 yrs
• 25% of individuals aged 40 yrs and older will
develop AF in their life time.

12. Prevalence of AF in the Renfrew-
Paisley study
Cohort of men and women aged 45–64 years (n = 15,406)
Reproduced with permission of the BMJ Publishing Group from Stewart S et al, Heart 2001: 86:516-21

13. Clinical events (outcomes) affected by
AF
Outcome Parameter Relative change in AF
patients
1.Death 1.Death rate is doubled
2.Stroke 2.Stroke risk increases 5
times
3.Hospitalisation 3.More frequent
4.Quality of life and 4.Can be markedly
exercise capacity decreased
5.LV function 5.Tachycardiomyopathy/
heart failure

14. Classification of AF
Terminology Clinical features
Initial event (first Symptomatic Rhythm/Rate
detected episode) Asymptomatic
Onset unknown
Paroxysmal Spontaneous termination Rhythm
<7 days and most often Control
<48 hours
Persistent Not self-terminating Rhythm or
Lasting >7 days or prior Rate control
cardioversion
Permanent Not terminated Rate Control
(‘accepted’) Terminated but relapsed
No
cardioversion attempt

16. Etiologies of AF
CARDIAC
Hypertensive heart disease
Valvular heart disease
Ischaemic heart disease
Cardiomyopathy
Pericarditis
Congenital heart disease
Post Cardiac surgery

17. Etiologies of AF contd:
NON CARDIAC
1. Pulmonary : Pneumonia, COPD,PE
2. Hyperthyroidism
3. Excess catecholamine /sympathetic activity
4. Drugs and alcohol
5. Significant electrolyte imbalance

18. LONE ATRIAL FIBRILLATION
• Younger patients < 60
• No underlying cause
• Usually not much symptoms
• Normal heart structure
• No associated co-morbidities

19. Why AF management is
important?
• extremely common
• Can lead to symptoms
• potentially serious consequences:
– embolism
– impaired cardiac output
– increased mortality

20. Management of Acute AF (<48 hrs)
• Haemodynamically unstable :
hypotension/heart failure/chest pain/syncope
Use DC Cardioversion
Haemodynamically stable :
Rate control : If significant tachycardia
Rhythm control : Flecainide, Propafenone (cl-
I) Amiodarone, Sotalol (cl-III)
Anticoagulant : LMWH

21. Treatment for permanent AF
• Heart Rate control
minimise symptoms associated with
excessive heart rates
prevent tachycardia-associated
cardiomyopathy
• Anticoagulation

22. Rhythm control as preferred
therapy
– ? First episode afib
– Reversible cause (alcohol)
– Symptomatic patient despite rate control
– Patient unable to take anticoagulant (falls, bleeding,
noncompliance)
– CHF precipitated or worsened by afib
– ? Young afib patient (to avoid chronic electrical and
anatomic remodeling that occurs with afib)

23. Rate control as preferred therapy
– Age > 65, less symptomatic, hypertension
– Recurrent afib
– Previous antiarrhythmic drug failure
– Unlikely to maintain sinus rhythm (enlarged LA)

24. Cardioversion
• Cardioversion is performed as part of a
rhythm-control treatment strategy
• There are two types of cardioversion:
electrical (ECV) and pharmacological (PCV)
• Cardioversion of AF is associated with
increased risk of stroke in the absence of
antithrombotic therapy.

26. AFFIRM : 5 Year Outcomes
Survival Rhythm Control Rate Control
1 year 96% 96%
3 year 87% 89%
5 year 76% 79%
p = 0.058
NO Difference : death, disabling stroke, major bleed,
or cardiac arrest
Sinus rhythm maintained in only 63% of rhythm
control group
NEJM 2002;347:1825

28. Rate Control Options
• Beta blocker
• Calcium channel blocker
• Verapamil, diltiazem
. Digoxin
• AV junction ablation plus pacemaker

29. STROKE RISK
Without AF
< 60 yrs : 0.5%
> 80 yrs : 3 yrs
With AF
< 60 yrs : 3%
> 80 yrs : 30%

33. Lip Y, et al. Chest 2010, 137(2):263

34. How do we determine stroke risk ?
– 0 points – low risk (1.2-3.0 strokes per 100 patient years)
– 1-2 points – moderate risk (2.8-4.0 strokes per 100 patient years)
– > 3 points – high risk (5.9-18.2 strokes per 100 patient years)

36. Atrial fibrillation 2009
Target INR 2-3

37. ACC AHA HRS Afib Focused Update
(Dabigatran), March 2011
• Non-inferior to warfarin re thromboembolism (afib)
• Caution when CrCl < 30ml/min
• Increased dabigatran levels with amiodarone, verapamil
• Half life 12-17 hours
• No reversal re hemorrhage
– dialysis
• Coagulation testing ??? aPTT, dilute thrombin time

38. Who should remain on warfarin?
• Patient already receiving warfarin and stable whose INR
is easy to control
• If dabigatran, rivaroxaban, apixaban not available
• Cost
• If patient not likely to comply with twice daily dosing
(Dabigatran, Apixaban)
• Chronic kidney disease (GFR < 30 ml/min)

39. Bleeding Risk
• Assessment of bleeding risk should be part of
the clinical assessment of AF patients prior to
starting anticoagulation
• Antithrombotic benefits and potential
bleeding risks of long-term coagulation should
be explained and discussed with the patient
• Aim for a target INR of between 2.0 and 3.0
• Forms of monitoring include point of care or
near patient testing and patient self-
monitoring

40. From Hart RG, et al. Stroke. 2005;36:1588

41. RF ABLATION THERAPY

42. Substrate for Substrate for
Triggering events
initiation perpetuation

43. When to consider ablation?
• Antiarrhythmic therapy ineffective
• Antiarrhythmic therapy not tolerated
• Symptomatic afib

46. Others in whom ablation may be a first strategy
• Patient very symptomatic in AF and refuses
antiarrhythmic drug therapy
• Young patient whose only effective antiarrhythmic drug
is amiodarone
• Patient with significant bradycardia for whom
antiarrhythmic drug therapy will require pacemaker

47. Summary
• AF is the commonest arrhythmia
• High prevalence
• Stroke is one of the most dreadful
complications .
• Different management strategies,